EVs and HEVs Using Lithium-Ion Batteries

10 EVs and HEVs Using Lithium-Ion Batteries Fabio Orecchini1, 2, Adriano Santiangeli2, *, Alessandro Dell’Era2 1

S E M—E NERGY AND M OBILITY SYS TEM S, CIRP S I NTERUNIVERSITY RESEARCH CE NTRE FOR SUSTAINA BLE D EVELOPMENT, S AP IENZ A U N I VE R S I T Y OF R O ME , R O M E , I T AL Y, 2 DME —DEPART ME NT OF ME CHANICS AND E NE RGY, “GUGLIELMO MARCONI” U N I V E RS I T Y , R O M E , I T AL Y * CO RR ESPONDING AUTHOR: A.SANTIANGELI@UNIMA RCONI.IT

CHAPTER OUTLINE 1. Introduction ................................................................................................................................... 207 1.1. The Innovation of Lithium-Ion Batteries ............................................................................. 207 1.2. Classification of Electric Vehicles.......................................................................................... 207 1.2.1. Microhybrid ................................................................................................................... 208 1.2.2. Mild (or medium) Hybrid ............................................................................................... 208 1.2.3. Full Hybrid ..................................................................................................................... 209 1.2.4. Plug-in HEV (PHEV)........................................................................................................ 209 1.2.5. Extended-Range EV (EREV) ............................................................................................ 209 1.2.6. Battery Electric Vehicle (BEV) ......................................................................................... 210 1.2.7. Fuel Cell Electric Vehicle (FCEV) ..................................................................................... 210 2. HEVs................................................................................................................................................ 210 2.1. Audi Q5 Hybrid (Full HEV) .................................................................................................. 210 2.2. BMW ActiveHybrid 3 (Full HEV) ......................................................................................... 211 2.3. BMW ActiveHybrid 5 (Full HEV) ......................................................................................... 212 2.4. BMW ActiveHybrid 7 (Mild HEV)........................................................................................ 212 2.5. BMW Concept Active Tourer (PHEV) ................................................................................. 214 2.6. BMW i8 (PHEV) .................................................................................................................... 215 2.7. Honda (Acura) NSX (PHEV) ................................................................................................. 216 2.8. Infiniti EMERG-E (EREV) ...................................................................................................... 216 2.9. Infiniti M35h (Full HEV)....................................................................................................... 217 2.10. Mercedes S400 Class Hybrid (Mild HEV) ............................................................................ 218 2.11. Mercedes E300 BlueTEC HYBRID (Full HEV) ...................................................................... 219 2.12. Mercedes Vision S500 Plug-in HYBRID (PHEV).................................................................. 219 2.13. Toyota Prius Plug-in (PHEV) ................................................................................................ 221 Lithium-Ion Batteries: Advances and Applications. http://dx.doi.org/10.1016/B978-0-444-59513-3.00010-8 Ó 2014 Elsevier B.V. All rights reserved.

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2.14. Toyota Priusþ (Full HEV) ..................................................................................................... 222 2.15. Volvo V60 Plug-in Hybrid (PHEV) ....................................................................................... 223 3. BEVs and EREVs ............................................................................................................................. 224 3.1. BYD e6 (BEV) ........................................................................................................................ 224 3.2. BMW ActiveE (BEV) ............................................................................................................. 225 3.3. BMW i3 (EV with EREV Possibility)..................................................................................... 226 3.4. Chevrolet Spark EV 2014 (BEV) .......................................................................................... 227 3.5. Chevrolet Volt (EREV).......................................................................................................... 227 3.6. Citroën C-Zero (BEV)............................................................................................................ 228 3.7. Citroën Electric Berlingo (BEV) ........................................................................................... 230 3.8. Fiat 500e (BEV)..................................................................................................................... 230 3.9. Ford Focus EV (BEV)............................................................................................................. 230 3.10. Honda FIT EV (BEV) ............................................................................................................. 232 3.11. Infiniti LE Concept (BEV) ..................................................................................................... 232 3.12. Mini E (BEV).......................................................................................................................... 233 3.13. Mitsubishi i-MiEV (BEV)....................................................................................................... 234 3.14. Nissan e-NV200 (BEV) .......................................................................................................... 234 3.15. Nissan Leaf (BEV) ................................................................................................................. 235 3.16. Opel Ampera (EREV)............................................................................................................ 235 3.17. Peugeot iOn (BEV) ............................................................................................................... 235 3.18. Renault Fluence Z.E. (BEV) .................................................................................................. 237 3.19. Renault Kangoo Z.E. (BEV).................................................................................................. 238 3.20. Renault Zoe Z.E. (BEV)......................................................................................................... 239 3.21. Smart Fortwo Electric Drive (BEV)...................................................................................... 239 3.22. Smart ED Brabus (BEV) ........................................................................................................ 239 3.23. Smart Fortwo Rinspeed DockþGo (BEV or EREV)............................................................. 241 3.24. Tesla Roadster (BEV)............................................................................................................ 241 3.25. Toyota eQ (BEV)................................................................................................................... 242 3.26. Volvo C30 (BEV) ................................................................................................................... 243 3.27. Zic Kandi (BEV)..................................................................................................................... 243 4. Electric Microcars ........................................................................................................................... 244 4.1. Belumbury Dany (Heavy Quadricycle) ................................................................................. 244 4.2. Renault Twizy (Light and Heavy Quadricycle) .................................................................... 245 4.3. Tazzari Zero (Heavy Quadricycle)......................................................................................... 246 5. New Concepts of Urban Transport Vehicles............................................................................... 246 5.1. Audi Urban Concept.............................................................................................................. 246 5.2. Opel Rak-E .............................................................................................................................. 247 5.3. PSA VELV ................................................................................................................................ 247 5.4. Volkswagen Nils..................................................................................................................... 248 6. Conclusions .................................................................................................................................... 248

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1. Introduction 1.1.

The Innovation of Lithium-Ion Batteries

Vehicle electrification proceeds at a quick pace and electric vehicles (EVs) will be placed in the market in limited although significant numbers in the next couple of years. Hybrid models continue to increase in terms of importance and presence in the market. In the past few years, they often appeared in the market and are presently relying on a generation of satisfied car drivers ready to ask—on the basis of the excellent results obtained—for drivetrains with an increased electric component. Fuel cell hydrogen cars are not ready for the market but they represent another element in favor of electrification, that makes its future marketing possible as an alternative or in parallel with hybrid electric vehicles (HEVs) and battery-powered EVs. Therefore, at least three large families of products should be considered: hybrid vehicles with internal combustion engines (ICEs) onboard, EVs powered by batteries recharged from outlets, and fuel cell hydrogen vehicles.

1.2.

Classification of Electric Vehicles

The classification adopted here distinguishes motor vehicles into HEV and battery electric vehicle (BEV). For an easier reference, we mention for each hybrid vehicle its classification according to the level of hybridization, therefore highlighting mild HEVs and full HEVs, and the possibility of external recharge (plug-in HEV (PHEV)). In the section devoted to BEVs, we also included extended-range electric vehicles (EREVs). A section has also been devoted to microcars powered by lithium-ion batteries. For an easier reading, specifications characterizing the level of electrification are reported. A car electrification “pathway” can be identified in the following sequence: nonhybrid vehicles, namely, ICE drive, HEVs (microhybrid, mild hybrid, full hybrid, and PHEV), EREVs, and BEVs. Table 10.1 shows an overview of the functions and features existing or possible in a vehicle, according to the different types of vehicles. Referring to the HEV, the adoption of the hybrid solution allows a marked reduction of consumption and emissions. In the case of hybrid electric systems, the presence of an electric motor allows a more efficient use of the heat engine, and the presence of electric power accumulators and electric motors allows energy recovery during braking and its subsequent use for traction purposes. A traditional classification of hybrid cars is proposed on the basis of the system architecture, namely, series hybrid (only the electric motor supplies power to the wheels), parallel hybrid (both the heat engine and the electric motor supply, in parallel, mechanical power to the wheels and are not connected to one another), and series-parallel hybrid (the electric motor and the heat engine, besides supplying mechanic power to the wheels, are also connected to one another). However, the classification presently adopted by all car manufacturers and experts of this sector refers to the degree of hybridization of the car, that is to say the ratio between the power of the heat engine/generator and the power of the electric motor (Table 10.1).

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Table 10.1

Different Vehicle Types and their Main Functions/Characteristics Function

System

Stop&start

Electric Traction

Regenerative Braking

Electric Driving Only

External Battery Charge

Conventional vehicle Micro-HEV Mild HEV/medium HEV Full HEV Plug-in HEV (PHEV) Extended-range EV (EREV) Battery electric vehicle (BEV) Fuel cell electric vehicle (FCEV)

Possible Yes Yes Yes Yes Yes Yes Yes

No No Limited Yes Yes Yes Yes Yes

No Minimum Yes Yes Yes Yes Yes Yes

No No Minimum Yes Yes Yes Yes Yes

No No No No Yes Yes Yes Yes1

1

Electric and/or hydrogen refueling.

1.2.1. Microhybrid The functions performed by the electric component in a microhybrid vehicle are mainly the following: • Power supply to electrically driven accessories, including air-conditioning. • Stop&start (putting the ICE in standby as soon as the vehicle stops, and automatically switching it on at restarting). • Brake energy regeneration (possibility of recovering part of the braking energy).

1.2.2. Mild (or medium) Hybrid The functions performed by the electric component in a mild hybrid vehicle are mainly the following: • Power supply to electrically driven accessories, including air-conditioning (already characterizing the microhybrid). • Stop&start (as in microhybrids). • Inactive timing system (when torque is not requested by the ICE, valves go to a sleep mode and do not absorb any energy and the ICE stops without really switching off) • Power supply for traction purposes; in particular, the electric motor provides power to the wheels when torque peaks must be reached (for instance at the start).1 • Brake energy regeneration. The main difference between this solution and the microhybrid consists in the fact that in this case the electric system significantly contributes to the powertrain. On the basis of the ratio between the power of the electric motor and the power of the ICE, reference is 1 In this way the torque provided by the ICE “flattens” with remarkable reductions in consumption and emissions.

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made to mild or medium hybrid. In any case, traction with the electric motor alone is not possible except for very particular conditions.

1.2.3.

Full Hybrid

In addition to the functions envisaged for micro and mild hybrids, a full hybrid vehicle allows starting and driving with the electric motor alone. Obviously, due to the limited size of electric motor and batteries, the all-electric range is limited. Therefore, summing up all the functions of a full hybrid system, the following characteristics are present: • Power supply to electrically driven accessories, including air-conditioning (as in micro and medium hybrid). • Stop&start (as in micro and medium hybrid). • Inactive timing system (when the ICE is not requested to supply torque, valves go to the sleep mode and do not draw any energy, and the ICE stops without really switching off) (as in mild and medium hybrids). • Power supply for traction purposes; in particular, the electric motor provides power to the wheels when torque peaks must be reached, e.g. at the start2 (already characterizing the mild and medium hybrid). • Brake energy regeneration3 (as in mild and medium hybrids). • Possibility of starting and driving in electric mode only with the zero-emission vehicle (ZEV) function. In addition to these, classification of electric cars include the following categories.

1.2.4.

Plug-in HEV (PHEV)

PHEV offer—as main differences compared to present hybrid cars—the possibility of recharging the batteries onboard from an electrical socket and the capacity to guarantee all-electric driving for a distance that is sufficient at least for daily average urban driving, i.e. from approximately 15 to above 100 km. Just as HEVs, PHEVs can be an intermediate step, if successful, toward purely electric vehicles. Charging can be: • Standard charge (domestic electricity supply, e.g. 220 V, 10 or 16 A). • Quick charge (dedicated charging station, e.g. 400 V from 32 to 63 A).

1.2.5.

Extended-Range EV (EREV)

An extended range EV (EREV) operates basically as a BEV for a certain driving range. As the battery is discharged, an ICE powers an electric generator for several hundred 2

In this way the torque provided by the ICE “flattens” with remarkable reductions in consumption and emissions. 3 As a matter of fact, it is possible to really recover only a part of the energy wasted during braking.

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kilometers of “extended-range” driving. Theoretically an EREV, referring to a traditional hybrid classification on the basis of system architecture, is a “series hybrid” (the engine supplying power to the wheels is the electric motor only). The functions performed by the electric component in an EREV are mainly the following: • • • • • • •

Power supply to electrically driven accessories, including air-conditioning. Stop&start. Power supply for traction purposes. Brake energy regeneration. Traction in electric mode (ZEV). Battery charging with the ICE. Plug-in charging possibility.

1.2.6. Battery Electric Vehicle (BEV) The functions performed by the electric component in a BEV are: • • • • •

Power supply to electrically driven accessories, including air-conditioning. Stop&start. Power supply for traction purposes in electric mode only (ZEV). Brake energy regeneration. Plug-in charging.

1.2.7. Fuel Cell Electric Vehicle (FCEV) The functions performed by the electric component in a fuel cell EV are: • • • • •

Power supply to electrically driven accessories, including air-conditioning. Stop&start. Power supply for traction purposes in electric mode only (ZEV). Brake energy regeneration. External charge: electric and/or hydrogen refueling.

2. HEVs 2.1.

Audi Q5 Hybrid (Full HEV)

Audi Q5 (Figure 10.1) has high-performance lithium-ion batteries (266 V/5 Ah) used for the first time in a hybrid sport utility vehicle (SUV). A four-cylinder 2.0 turbo fuel stratified injection (TFSI) with 155 kW (211 hp) and an electric motor with up to 40 kW (54 hp) and 210 Nm of torque work together to provide power. The quattro technology identifies the permanent all-wheel drive, distributed among the front and rear axles. Q5 hybrid quattro allows the selection of one out of the three

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FIGURE 10.1 Audi Q5 Hybrid—drivetrain. (For color version of this figure, the reader is referred to the online version of this book.)

drive options available. In “EV” mode, for instance, it is possible to drive in a purely electric mode, with a top speed of 100 km/h and with almost no noise emissions. The two other modes include “D”, which uses both engines to reduce consumption, and “S”, which allows an enhanced performance. The range in pure electric mode is up to 3 km at a constant speed of 60 km/h.

2.2.

BMW ActiveHybrid 3 (Full HEV)

BMW ActiveHybrid 3 is anticipated to be the world’s first compact premium sports sedan with full hybrid drive. In this car, the combination of an electrical engine and BMW TwinPower Turbo straight six-cylinder engine takes advantage of lithium-ion highperformance batteries coordinated by an intelligent hybrid system. The inline-six engine and the electric motor combine for 335 hp (246 kW) and 332 lb-ft (450 Nm) of torque. In addition to the boost available for the ICE, the electric motor is capable of powering the ActiveHybrid 3 with speeds of up to 45 mph (70 km/h) for distances of up to 2.5 miles (4 km). The electric motor is powered by a lithium-ion high-voltage battery, which was developed specifically for the BMW ActiveHybrid 3. The battery is encased in a special high-strength housing and is positioned between the wheel arches in the trunk (Figure 10.2). This provides optimal protection for the battery and helps ensuring a wellbalanced weight distribution. The battery, made up of 96 cells and with an effective energy of 675 Wh, has a cooling system integrated into the air-conditioning cooling circuit.

FIGURE 10.2 BMW ActiveHybrid. The lithium-ion high-voltage battery is housed under the boot. (For color version of this figure, the reader is referred to the online version of this book.)

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LITHIUM-ION BATTERIES: ADVANCES AND APPLICATIONS

BMW ActiveHybrid 5 (Full HEV)

BMW Series 5 is available in the ActiveHybrid version (Figure 10.3), with a 3.0-l engine and 250-kW/340-hp electric motor. This car is the first product of the European car industry in the sector of premium full hybrid sedans. It uses the TwinPower Turbo six-cylinder inline engine (225 kW/306 hp) of BMW 535i, coupled to a 40.5-kW/55-hp electric motor, thus leading to a total of 250 kW/340 hp. The power supply to the electric motor, allowing speeds of up to 60 km/h, is provided by a lithium-ion battery (675 Wh) housed in the trunk. An eight-speed automatic transmission transmits the torque of both engines to rear wheels. The vehicle is also equipped with an energymanagement electronic system, thanks to which, according to BMW, ActiveHybrid 5 consumes 20% less compared to 535i, with battery recharge in the start–stop function, electric boost during acceleration and electric gliding up to 160 km/h.

2.4.

BMW ActiveHybrid 7 (Mild HEV)

The 7-Series ActiveHybrid model (Figure 10.4), represents the first appearance on the market of a BMW mild hybrid. The rationale of this premium luxury vehicle is not represented by a consumption reduction, but rather the achievement of performance comparable to the higher category (V12) with a lower weight and higher range. For this reason, it has a twin-turbo V8 engine (330 kW), backed by an eight-speed automatic transmission, in addition to an electric motor of 15 kW and 210 Nm. In this way, the total power of ActiveHybrid 7 reaches 342 kW (slightly less than the arithmetic sum given the different power of the electric motor). The engine/generator block is coupled on the shaft before the torque converter and connected through a 120-V inverter to an 800-Wh lithium battery that provides the vehicle with 4 min of boost between 0 and 3500 revolutions (with more revolutions, the torque fall of the electric motor penalizes its efficient use). Battery charge during normal run occurs both through brake energy regeneration and directly through the engine, whenever the battery management system deems it suitable according to charge conditions. ActiveHybrid (mild hybrid) system obviously endows the vehicle with a stop&start function to avoid engine idling when the car stops. The electric motor also performs the starting function and replaces the 12-V generator, through a DC–DC converter. BMW ActiveHybrid system uses the hybrid technology to optimize

FIGURE 10.3 BMW ActiveHybrid 5. (For color version of this figure, the reader is referred to the online version of this book.)

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some services: for instance, the circuit of the two liquid intercoolers is also used to cool the DC–DC converter and all the power electronics. The 7-Series ActiveHybrid does not allow the traction in only in the electric mode. Figure 10.4 shows the ActiveHybrid system which includes (1) lithium-ion batteries (120 V, 800 Wh, 35 cells), (2) battery heating–cooling system, and (3) high-voltage wire for electric motor. Thanks to the lithium-ion batteries, with Series 7 Mild-Hybrid BMW took an important step forward along the way to the versatile use of electricity in vehicles. The energy generated by the brake energy regeneration system powers the battery, according to the driving conditions in different phases, making such energy available when needed. The system developed for BMW ActiveHybrid 7 is based on the lithium-ion technology with energy storage amounting to 400 Wh. It is made up of 35 cells and has an integrated control unit of the charge status, hence ensuring a suitable functioning of the system in different driving conditions, including variable temperature conditions. The lithium-ion

FIGURE 10.4 BMW 7 Series ActiveHybrid and detail of its lithium-ion battery. (For color version of this figure, the reader is referred to the online version of this book.)

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battery (37  22  32 cm [L,W,H]) weights 27 kg and is endowed with a liquid cooling system located in a highly resistant steel box placed in the boot, between the wheelhouses. In this way, battery protection and weight distribution are both guaranteed. The electric powertrain is located between the electric unit and the eight-speed Zahnradfabrik Friedrichshafen (ZF) transmission, so as to generate a 50:50 weight distribution (37  22  32 cm [L,W,H]).

2.5.

BMW Concept Active Tourer (PHEV)

The propulsion system of BMW Concept Active Tourer (Figure 10.5), interprets the rationale of the BMW Group in the field of sustainable mobility for the future. The propulsion technology of BMW hybrid plug-in models and electric models is identified with the name BMW eDrive. The range exceeds 20 km, allowing to efficiently use this car both in short and relatively long runs as well as in mixed drives. The heat engine is 1.5 l of the BMW EfficientDynamics range, whereas the electric motor developed by the BMW Group is synchronous. The 1.5-l petrol engine does not drive the rear wheels—as in all BMW models to date—but drives the front wheels. The electric motor acts on the rear axle and, if necessary, powers the car on its own. With a fully charged battery, the BMW Concept Active Tourer has a maximum range of over 30 km when running on electric power alone. Furthermore, the boost function can be applied to use the power provided by the synchronous electric motor for, e.g. highly dynamic acceleration maneuvers. The lithium-ion battery can be charged by any 220-V household power socket. Power can be drawn from both axes and fed into the lithium-ion battery so as to enhance the efficiency of this plug-in hybrid. While the electric motor automatically recovers maximum energy at the rear axle during deceleration, a high-volt generator connected to the combustion engine additionally charges the battery whenever needed. The vehicle is endowed with an intelligent energy-management system to increase the efficiency of the plug-in hybrid powertrain. An anticipatory operating strategy optimizes the efficiency of the electric motor and the high-performance battery. The system draws on data provided by the navigation system, calculating in advance the most suitable sections of the route and driving situations in which to apply electric drive or charge the

FIGURE 10.5 BMW Concept Active Tourer. (For color version of this figure, the reader is referred to the online version of this book.)

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battery. This optimized charging strategy saves up to 10% of energy so as to extend the amount of travel time during which the vehicle runs on electrical power alone.

2.6.

BMW i8 (PHEV)

The drive systems powering the BMW i8 Concept (Figure 10.6) are integrated in the front and rear axle modules, with the carbon fiber-reinforced plastic Life module providing a bridge between the two. The battery cells are stored in the Life module inside an energy tunnel, a structure similar to a central transmission tunnel. The front and rear axle modules therefore are connected with the passenger cell and with the battery to form a functional unit, which adopts not only load-bearing responsibilities but also extensive crash functions. The location of the high-voltage battery in the energy tunnel enhances its dynamics. Together with the positioning of the motor and engine over the axles, this results in a 50/50 weight distribution. Its innovative plug-in hybrid concept combines the modified electric drive system from the

FIGURE 10.6 BMW i8 Concept Spider. (For color version of this figure, the reader is referred to the online version of this book.)

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FIGURE 10.7 Honda (Acura) NSX. (For color version of this figure, the reader is referred to the online version of this book.)

BMW i3 Concept—fitted over its front axle—with a high-performance three-cylinder combustion engine producing 164 kW (220 hp)/300 Nm at the rear. The drive system generates combined output of 250 kW. The lithium-ion battery, specifically designed to this end and installed between the modules of the front and rear axles (Figure 10.6), can be recharged from a domestic power supply (total recharge in 2 h). The BMW i8 Concept can travel up to 35 km (w20 miles) on electric power alone.

2.7.

Honda (Acura) NSX (PHEV)

The hybrid plug-in NSX (Figure 10.7) represents the next generation of Honda highperformance cars. Making use of lightweight materials and a mid-mounted V-6 engine, the NSX Concept employs several new technologies for Acura, including application of Acura’s innovative new Sport Hybrid SH-AWDÒ (Super Handling All Wheel DriveÔ ) hybrid system. Utilizing a unique two-electric motor drive unit with a bilateral torque adjustable control system, the all-new hybrid all-wheel-drive system can instantly generate negative or positive torque to the front wheels during cornering. Acura anticipates the new Sport Hybrid SH-AWDÒ will deliver handling performance unmatched by previous AWD systems. In addition to the handling benefits of this car’s system, a powerful next-generation VTECÒ V-6 engine with direct-injection works together with a dual clutch transmission with built-in electric motor to create supercar acceleration while offering outstanding efficiency. The batteries of the electric powertrain are lithium ion. The new NSX, scheduled to launch within 2015, will be developed by the US Honda R&D Centre and produced in Ohio. The supersports car, developed in collaboration between Honda and its luxury brand Acura, adopts an innovative hybrid electric–gasoline system, for high performance and high range. The gasoline unit might be 3.5 V6 that, together with the electric motor, could reach a total power of 280 kW/380 hp, allowing a 0–100 km/h acceleration in 5 s.

2.8.

Infiniti EMERG-E (EREV)

Infiniti EMERG-E (Figure 10.8) propulsion is entirely provided by two Evo electric motors (150 kW each) powering rear wheels. A quartet of inverters controls the motors and their

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FIGURE 10.8 Infiniti EMERG-E. (For color version of this figure, the reader is referred to the online version of this book.)

energy regeneration under braking. The recovered power is directed to a lithium-ion battery mounted behind the seats. Batteries provide urban transport over a 50-km range; once the EV range is depleted, a 1.2 l, 35 kW light and compact three-cylinder petrol engine, provided by Lotus Engineering, fires up acting as a generator. The three-cylinder engine produces horsepower at 1500–4000 rpm, with a maximum power at 3500 rpm. According to the performance declared, Infiniti EMERG-E reaches a maximum speed of 220 km/h, with an acceleration of 0 to 100 km/h in 4.1 s and CO2 emissions of 55 g/km in the extended-range mode.

2.9.

Infiniti M35h (Full HEV)

This hybrid system (Figure 10.9), called “Direct Response Hybrid”, combines a 3.5-l V6 engine producing 306 hp and 350 Nm with a 68-hp electric motor and a torque of 270 Nm at 1770 rpm, powering rear wheels.

FIGURE 10.9 Infiniti M35h. (For color version of this figure, the reader is referred to the online version of this book.)

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This car has a seven-speed automatic transmission, including—instead of the torque converter—the electric motor linked to the drive shaft through a secondary clutch unit. Infiniti Direct Response Hybrid system can power M35h through its electric motor at zero emissions up to around 80 km/h. The Infinity hybrid system has a braking recovery system that extends the range of the 1.3-kWh, 340-V lithium-ion batteries installed in the booth, as can be seen in Figure 10.9. The maximum speed is electronically limited to 250 km/h, and performances were also obtained through an improvement of coefficient drag aerodynamics (Cx) that dropped from 0.27 to 0.26, and the weight was limited to 1830 kg as opposed to 1845 kg of M30d.

2.10.

Mercedes S400 Class Hybrid (Mild HEV)

Mercedes S-Class was put on the market more than 10 years after the world premiere of a hybrid model and 4 years after the launch of hybrid cars in the sector of premium brands (Lexus Rx 400h in June 2005). However, it is the first European car with a powertrain system with electric motor and batteries siding the traditional ICE and the first hybrid car in the world that adopted lithium-ion batteries on a production vehicle. The hybrid technology onboard the S-Class, of the mild hybrid type, has a 15-kW electric motor with stop&start function, coupled to a V6 petrol engine: the combined power is 220 kW and the maximum combined torque is 385 Nm. The lithium-ion battery pack is not only compact (directly installed in the engine compartment [Figure 10.10]) and light but also with a rather limited energy capacity. Compared to other hybrid cars on the market, Mercedes S-Class uses the electric support for more limited time fractions; however, in the homologation data, these small repeated interventions led to achieve excellent results, which can be summed up in the consumption of 7.9 l of petrol every 100 km, amounting to the emission of 186 g/km of CO2. The lithium-ion battery (produced by Continental with SAFT’s cells) guarantees an energy supply only sufficient for powertrain activations of few seconds. However, the difference from cars without electric motor is clear in terms of driving pleasure. Furthermore, the position of lithium-ion batteries allows to easily reach them as well as performing refrigeration directly with the car’s air-conditioning system.

FIGURE 10.10 Mercedes S400 Class Hybrid.

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2.11.

219

Mercedes E300 BlueTEC HYBRID (Full HEV)

BlueTEC HYBRID Mercedes E300 (Figure 10.11) has a 2.2-liter 4-cylinder diesel engine developing 204 hp, 500 Nm, combined with a 20-kW, 250-Nm electric motor enclosed in the transmission and powered by a 0.8-kWh lithium-ion battery located in the engine compartment. The range in all-electric mode is 1 km only, with a top speed of 35 km/h, whereas at a constant speed, up to 160 km/h, the ICE switches off and the electric motor alone powers the car by exploiting the inertia stored. The modular hybrid system with lithium-ion battery is borrowed from the flagship sedan S 400 Hybrid, and avails itself of systems such as start/stop, regenerative braking and the “boost” effect.

2.12.

Mercedes Vision S500 Plug-in HYBRID (PHEV)

The hybrid system of Mercedes Vision S500 Plug-in HYBRID (based on the S-Class) combines a 3.5-l petrol heat engine and a 44-kW electric motor allowing a 30-km

7G - TRONIC PLUS

Hybrid module including E-Motor (20 kW/250 Nm)

Electric motor 20 kW/250 Nm

HV electric regefrigerant compressor Diesel/gasoline engine

High-voltage lithium-ion battery

Power electronics

FIGURE 10.11 Mercedes E300 BlueTEC HYBRID. (For color version of this figure, the reader is referred to the online version of this book.)

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all-electric range. The battery is a 10-kWh lithium-ion pack, positioned between the wheel arches in the trunk, as shown in Figure 10.12. It can also be recharged at home sockets in only 4.5 h; if connection to a 20-kW electrical socket is possible, recharge is completed in 1 h. In this car too, logical management of the two engines allows shifting from a merely electric powertrain with short interventions of the six cylinders to a traditional petrol propulsion with electric “boosting” during top acceleration.

FIGURE 10.12 Mercedes Vision S500 Plug-in HYBRID: System layout. (For color version of this figure, the reader is referred to the online version of this book.)

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Toyota Prius Plug-in (PHEV)

The new Prius Plug-in features a claimed range of 25 km in purely electric drive (with a speed self-limited to 85 km/h), whereas its CO2 emissions, according to homologation data, amount to 49 g/km only, against 89 g/km of the standard model. By also considering the petrol engine, an overall range of 1200 km is allowed. The new Prius Plug-in, thanks to its 136 hp, has an acceleration 0–100 km/h in 11.4 s, and reaches 180 km/h of maximum speed by consuming 2.1 l/100 km of petrol, 45% less than standard Prius. Without the battery’s help, this car consumes around 3.7 l/100 km and its emissions amount to 85 g/km. Prius Plug-in has 4.4-kWh Li-ion batteries, positioned in the rear of the vehicle (Figure 10.13), with a capacity four times higher than normal Prius, whereas the total recharge time is 90 min. The engine is 1.8 l with an output of 99 hp and 142 Nm on Prius Atkinson cycle, whereas the permanent magnet electric motor is 60 kW/82 hp and 207 Nm. This car allows three types of drive: HV, EV and EV-City. The last of the three delays engine operation also in case of firm pressure on the throttle pedal. The Eco Mode modifies the

FIGURE 10.13 Toyota Prius Plug-in. (For color version of this figure, the reader is referred to the online version of this book.)

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electronic throttle control program and the operation of the air-conditioning system to maximize fuel savings, and an Eco Driving Support Monitor increases the information available as compared to the normal hybrid Prius.

2.14.

Toyota Priusþ (Full HEV)

The Hybrid Synergy Drive has been further improved. This technology exploits the maximum efficiency of electric motor and engine, thus obtaining a convenient balance between performance and consumption. During deceleration and under braking, kinetic energy is retrieved and converted into electric energy to be stored in the battery. The gear lever is electronically operated and drives the hybrid transmission through a planetary gear representing the heart of the hybrid system. Toyota Priusþ is equipped with a lithium-ion battery located inside the central console between the front seats, as shown in Figure 10.14; the new battery has 56 cells only, with a total weight of 34 kg; its compact structure occupies 50% less space than nickel–metal hydride, while allowing the same power with a weight reduction of 8 kg.

FIGURE 10.14 Toyota Priusþ. (For color version of this figure, the reader is referred to the online version of this book.)

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The Hybrid Synergy Drive of Priusþ combines 99 hp of the 1.8 petrol engine with 82 hp of the electric motor, thus reaching a maximum power of 136 hp. The consumption and emission levels amount to 4.1 l/100 km and 96 g/km of CO2, respectively. The Hybrid Synergy Drive system automatically starts the electric motor up to a maximum speed of 70 km/h, and then involves the 1.8 petrol engine. Buttons in the central console allow switching the “EV” mode on, for an exclusively electric use of the system; the “ECO” mode, for a relaxed driving style and an optimal management of consumption; or the “POWER” mode, through which the acceleration and driving pleasure are increased. More space was possible thanks to the installation of the new lithiumion battery within the vehicle central console between the front seats.

2.15.

Volvo V60 Plug-in Hybrid (PHEV)

Following its presentation at the Geneva Motor Show, Volvo V60 Plug-in Hybrid, was marketed in 2012 with 1000 units. It is the first hybrid car combining the plug-in and the diesel engine. It is powered by a five-cylinder, 2.4-l turbodiesel driving the front wheels and a 70-hp electric motor powering the rear ones. With overall 285 hp and a six-speed automatic transmission, Volvo makes the performance of V60 Plug-in Hybrid comparable to those of T6 petrol engines. The Swedish car manufacturer also stated that the 11.2-kW lithium-ion batteries (installed under the floor of the trunk as shown in Figure 10.15) can be recharged from a regular power outlet at home (230 V, 6 A, 10 A or 16 A), with times ranging between 3.5 and 7.5 h, according to the amperage.

FIGURE 10.15 Volvo V60 Plug-in Hybrid. (For color version of this figure, the reader is referred to the online version of this book.)

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3. BEVs and EREVs 3.1.

BYD e6 (BEV)

BYD (Build Your Dreams) e6 (Figure 10.16) is not new, as it was already presented at the Cobo Center in 2009 and 2010, but the renewed BYD e6-Eco presented at the Detroit Auto Show 2011 is getting closer to series production. This model proposes an electric alternative to Nissan Leaf and Chevrolet Volt. Technical features of the car include 60-kWh lithium iron phosphate batteries, rechargeable in 6 h and capable of powering a 75-kW electric motor. This car has a top speed of 140 km/h, and its range per charge is expected to be 300 km. In addition, during braking, deceleration and downhill coasting, the vehicle’s kinetic energy is converted into electrical energy and stored in the battery packs through regenerative braking functions. Resistant to high temperatures, high pressures and severe impacts, BYD’s internally developed battery features an excellent reliability and a 10-year warranty. The system can automatically detect leakage currents in the high-voltage power supply system and damages to the battery housings. An emergency maintenance switch disconnects the high-voltage battery pack to ensure safety of driver and passengers in case of system failures or when the car needs to be repaired. The parking gear motor controller receives the lock/unlock order sent by the driving motor and performs the relevant operations to ensure maximum safety while parking or starting. Charging the e6 is convenient and fast: it only takes 40 min to fully charge using the 100-kW fast charging cabinet and 6 h with a 10-kW standard charging pole. The environment-friendly e6 is a zero-direct-emission EV, which means that it emits no harmful toxic emissions, criteria pollutants or harmful greenhouse gases. BYD’s new lithium-ion battery takes the green philosophy a step further by using the only completely recyclable/disposable chemical formulations in a battery.

FIGURE 10.16 BYD e6. (For color version of this figure, the reader is referred to the online version of this book.)

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BMW ActiveE (BEV)

BMW ActiveE was presented at the 2010 Detroit Auto Show. It is a zero-emission 1-Series powered by an electric motor. Based on the same principles as Mini E, BMW ActiveE is a front-drive vehicle with an electric motor mounted on the rear axle. It uses two different lithium-ion battery packs, as shown in Figure 10.17: the first in the “traditional” area of the fuel tank (rear module) and the second replacing the distribution system (tunnel module). The 170 hp and 250 Nm maximum torque electric motor provides a top speed of 145 km/h and acceleration from 0 to 100 km/h in 9 s. The lithium-ion batteries promise an all-electric range of 160 km (FTP72 cycle range is calculated to be 240 km), and the ECOPRO system allows setting the onboard systems to optimize consumption with a

FIGURE 10.17 BMW Concept ActiveE. (For color version of this figure, the reader is referred to the online version of this book.)

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great attention to energy braking recovery; in city drive, the conventional braking system is seldom activated. Based on Series 1 Coupe´, ActiveE keeps the rear-wheel traction and guarantees a 50:50 weight distribution, thanks to the position of battery packs on axles and at the platform center. With a 32-A recharge device, the battery can be recharged in w5 h, while with a quick charge a “full battery” is obtained in 3 h.

3.3.

BMW i3 (EV with EREV Possibility)

BMW i3 Concept, designed and created directly as an EV (BMW i3 born electric), has a 125-kW/170-hp electric motor and delivers 250 Nm of torque; it is mainly designed for urban areas. Typical of an electric motor, maximum torque is developed from standstill, in contrast to an ICE where torque increases with engine rpm. This makes the BMW i3 Concept highly agile and provides impressive acceleration. It reaches a speed of 60 km/h in <4 s and 100 km/h (62 mph) in <8 s. Furthermore, the high torque is delivered over a very wide rpm range, resulting in very smooth power delivery. The single-speed gearbox provides optimal power transmission to the rear wheels and accelerates the BMW i3 Concept to an electronically governed 150 km/h without loss of power. As for other cars, the electric motor acts as a generator, converting kinetic energy into electricity which is then fed back into the battery. Energy recuperation generates a braking effect which makes a significant contribution to vehicle deceleration. Powered by lithium-ion batteries (which are smoothly integrated into the vehicle’s under body, as shown in Figure 10.18), BMW i3 has a range of 225 km with a total recharge time of 6 h at a standard power socket, and of 1 h (with 80% recharge) if a high-speed charger is used. The battery of BMW i3 Concept, thanks to an intelligent heating/cooling system, is always kept at its optimum operating temperature, which significantly helps to boost performance and life expectancy of the cells. BMW i3 Concept also offers the possibility of becoming an EREV, thanks to an optional range extender, Rex. Rex is a very smooth-running and quiet petrol engine that drives a generator which maintains the battery charge level, thus ensuring that the vehicle can continue to run on electric power.

FIGURE 10.18 BMW i3. (For color version of this figure, the reader is referred to the online version of this book.)

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227

Chevrolet Spark EV 2014 (BEV)

Chevrolet adds another car to its electric-powered line that includes the Volt: the Spark EV 2014, officially unveiled at the 2012 Los Angeles Auto Show. This car has 130 CV (110 kW) and nearly five times the torque of the gasoline version, delivering 542 Nm of torque instead of 112. Thanks to the 20-kWh lithium-ion battery (shown in Figure 10.19), the Spark EV is expected to provide an excellent range performance in its segment. The Chevrolet Spark EV will be the first EV to offer SAE Combo DC fast charging capability enables this EV to reach 80% battery charge in just 20 min. A full standard recharge takes w7 h on a 240-V charger.

3.5.

Chevrolet Volt (EREV)

On March 2012, the prize Car of the Year was awarded to Chevrolet Volt (Figure 10.20). The system is a series hybrid, i.e. the wheels of Volt are always activated by the electric motor. The energy stored in the 16-kWh lithium-ion battery guarantees a range of nearly 60 km (64 km is the official value of the test, in the motor vehicle emissions group (MVEG) urban cycle), but when the battery is almost exhausted, the petrol/ethanol engine is activated. In fact, there is a “traditional” petrol tank that fuels an electricity generator to recharge the battery or supply the electric motor when the lithium battery is discharged. With the battery exhausted, the Volt can still cover several hundreds kilometers. The total range is four times that of an EV, i.e. w480 km. The battery is 1676 mm long, weights 198 kg and is made up of 288 prismatic cells contained in each module. Energy is supplied to an advanced electric transmission unit of 110 kW and 370 Nm torque, with a maximum speed of 160 km/h. Volt can be recharged at home through a standard 230-V outlet by using the recharge set provided. Battery operation can be influenced by extreme temperature conditions. Volt’s lastgeneration lithium-ion battery has an internal management system with active control

FIGURE 10.19 Chevrolet Spark EV and its nanophosphate lithium-ion battery. (For color version of this figure, the reader is referred to the online version of this book.)

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FIGURE 10.20 Chevrolet Volt and its battery. (For color version of this figure, the reader is referred to the online version of this book.)

that allows keeping temperature within optimal values to maximize efficiency and charge duration. VoltecÒ components and battery are safe and guaranteed 8 years or 160,000 km. The Voltec system is made up of two electric motors, a 150 hp primary one and a 72 hp auxiliary one that comes into operation to support the first one whenever the car speed exceeds 100 km/h. Additionally, the car is supplied with a third 1.4 l petrol engine that supports the other two motors and never directly intervenes in the propulsion, as it is only used to recharge the auxiliary motor. In any case, the petrol engine never comes into operation, unless the charge level of the battery pack drops below 30% of total charge.

3.6.

Citroën C-Zero (BEV)

C-Zero, in Figure 10.21, was developed in collaboration with Mitsubishi Motors Corporation. Being an all-EV, it has a permanent magnet synchronous motor that develops 47 kW from 3000 to 6000 rpm. The maximum torque reaches 180 Nm, from 0 to 2000 rpm, and the power is sent to the rear wheels via a single-speed reduction gear. The permanent magnet motor is located in the rear and transfers power to the wheels, turning C-Zero into the first rear-drive Citroe¨n of the new millennium and the first rear-drive Citroe¨n car after 77 years. The motor is powered by a latest-generation lithium-ion battery, placed at the center of the vehicle: eighty-eight 50-Ah cells (for an onboard energy of 16 kWh) provide power at 330 V. The lithium-ion technology is resistant to partial recharges, which have no impact on battery longevity. Recharging batteries is really easy: the supply cable is plugged to a

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EV system configuration Normal charging connector (100 V–200 V) CAN

Combination meters

Onboard charger Battery management unit

Inverter

DC/DC converter

A/C ECU Controller area network (CAN)

EPS

Brake

EV-Engine control unit (ECU)

Selector lever

Cell monitor Cell monitor unit unit Battery Battery module module A/C compressor

Motor

Transmission

Heater

Quick charging connector

Charging-to-driving process Normal charging Power supply

Onboard charger

Drive battery

Inverter

Motor

Transmission

Driving

Quick charging Charging

Electricity generation

Regenerative brakes

FIGURE 10.21 Citroën C-Zero and its EV system configuration.

220-V socket. A complete recharge takes 6 h, whereas an 80% charge is possible in only 30 min by using a dedicated station with a single-phase current of 125 A, 400 V, for a maximum power of 50 kW. As for the top speed, the manufacturer indicates a peak of 130 km/h, with acceleration from 0 to 100 km/h in 15.9 s and from 60 to 90 km/h in 6 s. The officially declared maximum range of 150 km is obtained with an Eco drive.

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Citroën Electric Berlingo (BEV)

Designed to appeal to business customers, the Berlingo Electric (Figure 10.22) features a 22.5-kWh lithium-ion battery which powers an electric motor that develops 49 kW and 200 Nm of torque. It enables the model to travel up to 170 km on a single charge. When the battery is depleted, it can be fully recharged in approximately 6–12 h with a standard household outlet. The quick-charge mode can give the battery an 80% charge in just 30 min. Since the electric powertrain is packaged under the hood and body shell, the van has a cargo capacity of 4.1 m3 and a payload capacity of 675 kg. The van Berlingo Electric will go on sale in 2013 and its price will be announced the moment it will be launched.

3.8.

Fiat 500e (BEV)

This car will not be available in Europe until 2013. Chrysler, the automotive partner of Fiat, announced the production of electric 500 for the US market as from 2012. Regarding the look of the new “American” 500, the design is similar to the Abarth version, that is to say more aggressive and sports. Although neither Chrysler nor Fiat released any official data, 500 BEV (Figure 10.23) is probably going to be equipped with 22-kW lithium-ion batteries providing it with an average range of 140 km and a top speed of 115 km/h. While announcing the development of this “zero-emission” 500, Chrysler stated that it is involved in a test funded by the US Energy Department to increasingly promote the development and production of low environmental impact cars by US car manufacturers.

3.9.

Ford Focus EV (BEV)

EV Ford Focus (Figure 10.24) is powered by a permanent magnet electric motor that produces 145 hp and 250 Nm of torque; according to Ford, it can reach 136 km/h and the

FIGURE 10.22 Citroën Electric Berlingo. (For color version of this figure, the reader is referred to the online version of this book.)

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FIGURE 10.23 Fiat 500e BEV. (For color version of this figure, the reader is referred to the online version of this book.)

FIGURE 10.24 Ford Focus EV. (For color version of this figure, the reader is referred to the online version of this book.)

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range should be 160 km. Full recharge of the lithium-ion batteries (23 kWh, liquidcooled/heated, recyclable) might require from 3 h (using the 220 V current from an industrial socket) to 11 h (if recharged from a domestic socket). The battery will not be for rental, and it should have a 5-year warranty. Among the technological characteristics of electric Ford Focus there is a special system regulating the temperature in the battery system to cool or heat the accumulators according to external conditions, without impacting on the range. Thanks to the MyFord touch technology for EV Focus, an innovative presentation of car information is available, including the level of battery charge, the location and distance of charging stations and the range. It is also possible to plan an itinerary with stops for charging the vehicle. Electric Focus 2012 also includes alarms to warn pedestrians whenever the EV is moving at low speed.

3.10.

Honda FIT EV (BEV)

In the United States, the new Honda Fit EV (Figure 10.25) was officially rated by the Environmental Protection Agency with an average consumption of 118 mpge, the unit specifically established by the Agency for battery-powered vehicles. Honda FIT has got a record rating, outperforming the ones previously obtained by Mitsubishi i-MiEV (112 mpge), Ford Focus Electric (105 mpge) and Nissan Leaf (99 mpge). FIT has a 20-kWh lithium-ion battery pack, powering an electric motor of 92 kW and 256 Nm of torque. Full recharge needs less than 3 h with a 240-V charger, providing an expected range of around 130 km. This car has three driving modes to privilege either performance or consumption, similar to CR-Z Hybrid.

3.11.

Infiniti LE Concept (BEV)

Infiniti LE Concept, in Figure 10.26, was also exhibited at the Paris Motor Show in 2012 (its European first). A production version is expected to reach Infiniti showrooms in near-similar form in 2013–2014 as Infiniti’s first zero-emission luxury sedan. It has a highperformance 100-kW (134 hp) electric motor, and a torque of 325 Nm instantly available. Its range will be w160 km.

FIGURE 10.25 Honda FIT EV. (For color version of this figure, the reader is referred to the online version of this book.)

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FIGURE 10.26 Infiniti LE Concept. (For color version of this figure, the reader is referred to the online version of this book.)

The main characteristics of Infiniti LE Concept include the original and luxury passenger compartment marked by highly technological interior, leading-edge lithiumion battery, and innovative home-based wireless charging system with intelligent parking assist. The battery system is a 24-kWh lithium-ion design with a ChaDeMo DC 50 kW quick charger that can deliver an 80% charge in 30 min. The home-based wireless charging system uses a coil safely encased in the charging pad to charge the battery via inductive energy flow. The intelligent park assist will automatically align the vehicle over the charging pad for optimum charging and the driver can walk away, with no cables to connect. The high-frequency, noncontact charging, controlled by the car’s display or by smartphone, can be installed easily in a home garage. Infiniti LE is expected to be marketed in 2014.

3.12.

Mini E (BEV)

BMW performed a number of tests in the field of lithium-ion-battery-powered motors with a fleet of 500 Mini. Mini E (Figure 10.27) is equipped with a 150-kW electric motor, with a torque of 220 Nm (8.5 s from 0 to 100 km), powered by a 35-kWh latest-generation lithium-ion battery able to guarantee a range of nearly 200 km. A full recharge can be done in 2.5 h by connecting the vehicle to a suitable socket provided by BMW—the so-called Wall Box—which can be mounted where the car is usually parked. BMW claims

FIGURE 10.27 Mini E. (For color version of this figure, the reader is referred to the online version of this book.)

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FIGURE 10.28 Mitsubishi i-MiEV. (For color version of this figure, the reader is referred to the online version of this book.)

great economic advantages using this vehicle, also considering that the consumption for a full recharge amounts to 28 kWh of current. The maximum speed is electronically limited to 152 km/h.

3.13.

Mitsubishi i-MiEV (BEV)

Mitsubishi i-MiEV (Figure 10.28) is endowed with (1) an efficient 47-kW permanent magnet synchronous electric motor powered by high-energy-density lithium-ion batteries and (2) a lightweight speed-reducing gear transmission which allows to best exploit a typical characteristic of electric motors as the high low-end torque. Thanks to this, an official range of 130 km with a single charge can be achieved. The charge can be made in three different ways: with a regenerative braking, by connecting the vehicle to a normal 100- to 200-V domestic socket, or in quick-charge mode at high-voltage stations.

3.14.

Nissan e-NV200 (BEV)

Nissan e-NV200 (Figure 10.29) shares its major drivetrain components with the innovative Nissan Leaf, and the power is supplied by lithium-ion batteries. In this way, it will be

FIGURE 10.29 Nissan e-NV200. (For color version of this figure, the reader is referred to the online version of this book.)

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possible to recharge the battery to 80% capacity in <30 min by a quick charging system. Furthermore, a particular adapter allows to harness the energy stored in the batteries to power electric equipment with a maximum power of 1500 W. The lithium-ion battery, made up of 48 compact modules, is coupled to an 80-kWh AC synchronous motor generating a 280-Nm torque. Running is silent and without polluting emissions. The motor delivers its maximum torque at the start, providing instant acceleration and smooth running. Transformation of Nissan NV200 into an EV did not change internal space and carrying capacity of the vehicle. By positioning the battery pack under the platform, e-NV200 can carry two standard Euro pallets between the rear wheel arches or 20 Euro boxes thanks to a load volume of 4.3 m3. The official presentation of e-NV200 will be made during the Hannover Motor Show, and the mass production will begin in 2013.

3.15.

Nissan Leaf (BEV)

Leaf is a hatchback car and has five doors, five seats, and 4.44 m length with 80-kW, 280-Nm electric motor (comparable to a 1.6 l diesel engine). The 24-kWh and 90-kW Liion batteries (48 modules, 360 V nominal voltage, 192 laminated prismatic cells), shown in Figure 10.30, are 80% rechargeable in 30 min from the quick recharge units or in 8 h from the normal domestic sockets. The Leaf has an average range of 175 km. The commercial formula selected envisages to sell the vehicle to customers and to lease the battery pack in order to reduce the price impact. Nissan Leaf has been named 2011 World Car of the Year (also 2011 European Car of the Year).

3.16.

Opel Ampera (EREV)

In addition to a powerful 16-kWh lithium-ion battery, this car has a unique electric propulsion system that extends its driving range. For the first 40–80 km, power is supplied by the electricity stored in the 16-kWh lithium-ion battery. When the Ampera’s battery reaches its lower V limit, the battery can be recharged in less than 4 h at 230 V by plugging the vehicle’s onboard charge system into a standard outlet. Because the battery can be recharged quickly, most Amperas are likely to be driven in battery mode nearly all the time. If a longer trip is required, the gasoline-fueled engine/ generator can seamlessly extend the total driving range to more than 500 km on a full tank. Every element of the Ampera was designed and analyzed for efficiency, making the Ampera, in Figure 10.31, one of the most aerodynamic and energy-efficient vehicles in the market. Opel Ampera was “Car of the Year 2012”.

3.17.

Peugeot iOn (BEV)

Peugeot iOn (Figure 10.32) represents Peugeot’s city car developed on the basis of Mitsubishi i-MiEV (as Citroen C-Zero) and derives from an agreement between the two carmakers. The 100% electric-drive iOn is equipped with a permanent magnet

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FIGURE 10.30 Nissan Leaf and its lithium-ion batteries. (For color version of this figure, the reader is referred to the online version of this book.)

FIGURE 10.31 Opel Ampera. (For color version of this figure, the reader is referred to the online version of this book.)

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FIGURE 10.32 Peugeot iOn. (For color version of this figure, the reader is referred to the online version of this book.)

synchronous motor (47 kW (64 hp)) working at 3000–6000 rpm. The rear-mounted electric motor drives the back wheels, making this the first rear-drive Peugeot car after 20 years (the last one was Peugeot 505, produced until 1992). The motor is powered by lithium-ion batteries having eighty-eight 50-Ah cells, which can be charged at a 220-V socket. The Peugeot iOn can be fully charged in 6 h and to 30% charge with a 30-min quick charge. The car is also very easy to use, since it can be driven like a normal city car. Furthermore, the characteristics of the electric motor, making the maximum torque immediately available, entail no need for gear changes; however, a gear selector is available, similar to a gear lever. iOn has a top speed of 130 km/h, needs 15.9 s to get from 0 to 100 km/h, and has a maximum range of 150 km.

3.18.

Renault Fluence Z.E. (BEV)

This vehicle was first shown in 2009 at the Frankfurt Motor Show in the form of a concept car, before being presented in the definitive form. It is an all-electric saloon aimed at private buyers or fleet owners. The bodywork is inspired by the ICE Renault Fluence. The electric version of Renault Fluence is 4.75 m long—13 cm more than the ICE version—to make space for the batteries behind the rear seats. Fluence Z.E. (Figure 10.33) is similar to Fluence, although the differences are that the rev counter has been replaced by a display with information on range and charging, and that the central console includes the displays “forward”, “reverse”, “neutral” and “parking” which are the different positions for the transmission control lever. Fluence Z.E. has a synchronous electric motor with rotor coil, with a peak power of 70 kW (w94 hp) at 11,000 rpm and a maximum torque of 226 Nm allowing a top speed of 135 km/h. The lithium-ion battery (22 kWh, 250 kg) allows a range of up to 160 km in a mixed cycle and can be recharged in three different ways: using a 10-A or 16-A, 220-V household outlet in 6–8 h; using 32-A, 400-V public charge spots in 30 min; and using the Quickdrop system that allows to quickly switch for a charged battery at a dedicated battery exchange facility in w3 min.

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FIGURE 10.33 Renault Fluence Z.E. (For color version of this figure, the reader is referred to the online version of this book.)

FIGURE 10.34 Renault Kangoo Z.E. (For color version of this figure, the reader is referred to the online version of this book.)

3.19.

Renault Kangoo Z.E. (BEV)

Presented at the Hanover Motor Show in 2010, Renault Kangoo Z.E. (Figure 10.34) was appointed International Van of the Year 2012. It was the first EV to win this title. The motor, placed under the hood, develops 44 kW and runs on a 22-kWh lithium-ion battery placed under the floor. The vehicle range—170 km in an new european driving cycle (NEDC) combined cycle—may vary with conditions of use: driving style, temperature, topography or speed. With a maximum torque of 226 Nm available from start-up, strong acceleration and pick-up from low engine speeds, and no noise or gear changing, the vehicle sets new standards in performance and driving comfort. To manage vehicle range, the dashboard was redesigned to include a new interface informing the driver of the remaining battery charge and range. An Eco driving system and function to preheat the vehicle during charging have also been developed. To further reassure customers and optimize range, Renault is marketing connected services for drivers (connected pack) and fleet managers (fleet asset management).

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FIGURE 10.35 Renault Zoe Z.E. (For color version of this figure, the reader is referred to the online version of this book.)

3.20.

Renault Zoe Z.E. (BEV)

Zoe Z.E. (Figure 10.35) has a 226-Nm, 70-kW electric motor that allows this modern 1400-kg coupe´ to reach 140 km/h and cover up to 160 km with fully charged lithium-ion batteries. The 22-kWh battery pack allows using Zoe in city driving for 100 km (in the winter) or 150 km (in the summer), thanks to the Range OptimiZEr technology combining regenerative braking, a heat pump and Michelin Energy E-V tires. The new Chameleon charger allows the vehicle (1) to be charged via any outlet, (2) to accept any amperage, and (3) to benefit from a rapid charge up to 43 kW, recovering 80% of battery capacity in less than 30 min. The Chameleon charger allows car charge via a 3-kW/16-A home box in 9 h, in 1 h at a 22-kW/32-A three-phase charging station, or in just 30 min at a 43-kW/63-A charging station. Furthermore, in specific quick recharge units and with the “Quickdrop” system (3 min), the entire battery can be replaced. The battery pack is under the floor, so the passenger compartment may contain up to five passengers, and the boot has a volume of 338 l. At speeds >30 km/h, all the safety devices are activated, such as drivers and passengers airbags, and the Zoe vocally informs about the presence of pedestrians.

3.21.

Smart Fortwo Electric Drive (BEV)

Since 2012, Smart Fortwo Electric Drive (Figure 10.36) is an integral part of the Smart range. It is equipped with a 35-kW (51 hp) permanent magnet motor providing 120 Nm of torque and with the new water-cooled 17-kWh lithium-ion battery by Tesla Motors, allowing a range of at least 135 km at a speed of 100 km/h. The battery recharge time ranges from 3 h, in case of urban drive, to 6 or 8 h for a full recharge. While the Smart is being recharged, through an electric outlet, its special “onboard unit” will continuously collect precious information on its use. In this way, the driver will be constantly informed about developments of this new Smart model.

3.22.

Smart ED Brabus (BEV)

This ED Smart “by Brabus” (Figure 10.37) is more powerful than the standard version: it has up to 60 kW and a torque of 135 Nm. This increased performance is supported by sports suspensions that drop the car 1 cm closer to the asphalt and a sports steering wheel with paddles that allow the driver to adjust the level of energy regeneration. A suitable

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FIGURE 10.36 Smart Fortwo Electric Drive. (For color version of this figure, the reader is referred to the online version of this book.)

FIGURE 10.37 Smart ED Brabus. (For color version of this figure, the reader is referred to the online version of this book.)

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FIGURE 10.38 Smart Fortwo Rinspeed DockþGo. (For color version of this figure, the reader is referred to the online version of this book.)

noise generator simulates the noise of a sports engine; it is a device targeted to increase safety for pedestrians and at the same time to provide drivers with higher driving pleasure.

3.23.

Smart Fortwo Rinspeed DockþGo (BEV or EREV)

Smart Fortwo Rinspeed DockþGo (Figure 10.38) can be extended thanks to a trailer, which may also transport an additional battery or a range extender heat engine. It is a particular version of Smart Fortwo to which a sort of “trail” was added, able to act as additional boot. DockþGo is only referred to the trail, made up of an independent axle that could in theory be used with any electrified speedster.

3.24.

Tesla Roadster (BEV)

Tesla Roadster (Figure 10.39) is an EV sold since 2008 by Tesla Motors. It is a roadster, that is to say a two-seat sports car with three-phase four-pole electric induction motor coupled to a single-speed Borg Warner transaxle producing a maximum torque at 14,000 rpm, reaching a top speed of over 200 km/h (electronically limited) and developing an acceleration from 0 to 100 km/h in 3.9 s. The onboard computer allows to select among five drives: Maximum Performance, Maximum Range, Standard, Storage, Valet, and manages the recharge system of its lithium-ion batteries. These batteries provide the vehicle with a range of up to 392 km, and their full charge through recharging units takes w3.5 h, whereas 2 h are needed for an 80% recharge. Charging from a standard domestic outlet needs 10–15 h.

FIGURE 10.39 Tesla Roadster. (For color version of this figure, the reader is referred to the online version of this book.)

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Tesla Roadster was one of the first vehicles equipped with regenerative braking. The Sport Model is the sportiest version of Tesla Roadster. Compared to the first model, its performance was improved thanks to a 15% increase in torque power, i.e. 288 hp vs. 248 hp of the previous version. Furthermore, the Sport Model has improved suspensions, which are adjustable according to drivers’ needs, and accelerates from 0 to100 km/h in 3.7 s, improving by 0.2 s the performance of the standard model. The new Model S, the sports sedan, and the Model X, the high-performance electric SUV, will be available from 2013, with 20 units of the former produced every year.

3.25.

Toyota eQ (BEV)

The new Toyota eQ will be powered by Panasonic’s lithium-ion batteries (Figure 10.40). Panasonic batteries already power Prius’ hybrid models; the supply to Toyota now includes all-EVs as well. Toyota has launched eQ, in Japan and the United States in December 2012, but its 2010 promises of several thousand cars/year were significantly scaled back to just 100 fleet-oriented vehicles. This all-EV is based on Toyota’s gas-powered iQ city car, with four seats and a range of up to 100 km (62 miles) on a single charge of its new 12 kWh Li-ion battery. Internal volume and boot size are also the same as those of the iQ city car, as the lithium-ion batteries are mounted under the floor. At a mechanical level, iQ EV has an electric motor that develops 64 hp and 163 Nm of air-cooled torque, a 150-cell battery pack, a 3-kW water-cooled battery charger, an inverter, a DC/DC converter and a motor speed reduction mechanism. Top speed is 125 km/h and 0–100 km/h acceleration takes 14 s. The vehicle has a range of 85 km and can have a complete recharge in w3 h from a 200-V outlet. A quick 80% charge can be achieved in just 15 min. Starting from 2013, Toyota has also planned wireless battery charging trials in Toyota City, using wireless coils embedded in the road and in the chassis of the car, to evaluate their efficiency.

FIGURE 10.40 Toyota eQ. (For color version of this figure, the reader is referred to the online version of this book.)

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FIGURE 10.41 Volvo C30 BEV. (For color version of this figure, the reader is referred to the online version of this book.)

3.26.

Volvo C30 (BEV)

Volvo C30 BEV (Figure 10.41) is the first EV of the Swedish manufacturer. The platform is new and takes into account the volume of the battery pack: the split-pack design, part in the tunnel and part in the tank area, has a capacity of 24 kWh at 400 V with single 3.7-V cells. Enerdel supplies lithium-ion batteries guaranteeing a range of 120–150 km by employing 21.5 kWh only; the car is also endowed with a specific cooling–heating system that keeps temperature in the 0–30  C range. In very cold days, the presence of an auxiliary ethanol heater allows to rapidly bring the car temperature to a suitable level. A timed system allows one to have the car ready (warm in the winter and cold in the summer) at the time scheduled for starting. The charging time is 8–10 h depending on the current (16 or 10 A, respectively). The traditional attention paid by Volvo to safety led to place batteries in an area protected from crashes, including a front structure that takes into account the lower resistance to crashes by the electric motor. The maximum speed is electronically limited to 130 km/h and acceleration from 0 to 100 km/h is provided in 10.5 s. The power of 40 kW at 11,000 rpm (82 kW for a peak of 45 s), with maximum torque of 220 Nm from zero, is sufficient for a rapid and smooth pick-up. The dashboard has an indicator of consumed or recovered power and a small display indicating the electric consumption of accessories, all powered electrically, including air-conditioning.

3.27.

Zic Kandi (BEV)

Equipped with a lithium-ion battery (LiFePO4, capacity: 14.1 kWh), the two models Kandi Zic S and Zic L (Figure 10.42) provide a range of 120 km. A full recharge takes 2 h; the electric motor is a 72-V AC (7.5 kW) and the net weight (without batteries) is 670 kg. These cars are equipped with a speed reducer that, when inserted, limits the speed to 50 km/h, thus increasing battery life between charges. This was obviously developed for city driving, i.e. for average speeds less than 35 km/h. If, however, the traffic and

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FIGURE 10.42 Zic L. (For color version of this figure, the reader is referred to the online version of this book.)

speed limits allow it, the car can resume its usual performance and a maximum speed of 75 km/h can be reached.

4. Electric Microcars This section describes some of the many electric microcars available in the market. These cars are also named quadricycles, in Europe, and low-speed vehicle (LSV) in the United States, with a specific definition of electric microcars as neighborhood electric vehicles (NEVs). More particularly, in Europe, quadricycles are categories of four-wheeled microcars defined by limitations in terms of weight, power and speed and are classified into light quadricycles and heavy quadricycles, both with a maximum speed of 50 km/h. In the United States, LSVs must have a top speed of 20–25 mph (32–40 km/h) and NEVs are limited to roads with posted speed limits as high as 45 mph (72 km/h) depending on the particular state laws; they are usually built to have a top speed of 30 mph (48 km/h).

4.1.

Belumbury Dany (Heavy Quadricycle)

Conceived, designed and produced in Italy, this city car comes in two versions with either petrol engine or electric motor. The electric car version, Figure 10.43, has three to four seats and a maximum speed of 85 km/h, with a range of 150–170 km in optimum conditions. The battery full charge is obtained in 8 h. Electric power is stored in a 9-kWh lithium iron phosphate battery pack. The car weight, without batteries, is 179 kg.

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FIGURE 10.43 Belumbury Dany. (For color version of this figure, the reader is referred to the online version of this book.)

4.2.

Renault Twizy (Light and Heavy Quadricycle)

Twizy (Figure 10.44), the first 100% electric urban crosser, is practically half car and half scooter. Produced since 2011 by the French carmaker Renault, this vehicle is classified as a motorcycle (therefore, it does not need to comply with traffic rules for cars). It is classified as either light or heavy motorcycle according to the version; indeed, Twizy is available in two versions, both fully electric and with an asynchronous motor. In the case of the light motorcycle, it has a maximum power of 9 hp, sufficient to reach 45 km/h, whereas in the case of the heavy motorcycle of 17 hp, a speed of 80 km/h can be reached. Thanks to its low weight, including the 100-kg batteries, the vehicle is able to guarantee agility in city traffic. Twizy’s weight ranges from 446 kg to 473 kg. The lithium-ion batteries provide a range of up to 100 km. Air-conditioning is not available in any version, since this device would absorb a considerable quantity of energy, entailing the need for more powerful batteries.

FIGURE 10.44 Renault Twizy. (For color version of this figure, the reader is referred to the online version of this book.)

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FIGURE 10.45 Tazzari Zero. (For color version of this figure, the reader is referred to the online version of this book.)

4.3.

Tazzari Zero (Heavy Quadricycle)

This car, produced in Italy, features high technology and quality at a competitive price (Figure 10.45). It is a two-seater vehicle with a top speed of 100 km/h and a range of 140 km in optimum conditions. The lithium-ion battery (15 kW) can be fully charged in 9 h. The vehicle’s weight is 400 kg (batteries excluded).

5. New Concepts of Urban Transport Vehicles 5.1.

Audi Urban Concept

Audi Urban Concept Sportback (Figure 10.46) is a concept city EV (3.22 m long, 480 kg). The passenger seat is moved back 30 cm to provide sufficient shoulder and elbow room. The 7.1-kWh lithium-ion battery (90 kg) is located behind the seats. The two electric motors develop a combined output of 20 hp and 47 Nm of torque. The motors are mounted between the rear wheels, which they drive via a single-speed transmission. The Audi Urban Concept accelerates from 0 to 100 km/h (62.1 mph) in 16.9 s. It reaches 60 km/h (37.3 mph) in w6 s. Top speed is limited to100 km/h. In the European driving cycle, a range of 73 km is calculated. The battery recharges completely in about 20 min with 400-V three-phase current, and in approximately 1 h with household current. Audi also developed a wireless charging system.

FIGURE 10.46 Audi Urban Concept. (For color version of this figure, the reader is referred to the online version of this book.)

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FIGURE 10.47 Opel Rak-E. (For color version of this figure, the reader is referred to the online version of this book.)

5.2.

Opel Rak-E

Opel’s electric concept tandem two seater was presented as a “revolutionary vehicle for zero-emission urban mobility”. Opel Rak-E (Figure 10.47) is in-between a car and a motorcycle. With a 100-km range, Rak can reach 120 km/h, and 3 h are needed for a full recharge from a home outlet.

5.3.

PSA VELV

PSA VELV (Figure 10.48) can seat three people in the passenger compartment accessed through butterfly doors. Its limited size allows a turning radius of 7.2 m and a weight of 650 kg. According to the French carmaker, it could be of interest for rental companies, and also as a spare car for private drivers. It provides a range of 100 km. PSA Peugeot Citroen VELV has a 20-kW electric motor powered by lithium-ion batteries that, with a range of 85 Wh/km, provides this ZEV with a top speed of 110 km/h and a total range of 100 km.

FIGURE 10.48 PSA VELV. (For color version of this figure, the reader is referred to the online version of this book.)

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FIGURE 10.49 Volkswagen Nils. (For color version of this figure, the reader is referred to the online version of this book.)

5.4.

Volkswagen Nils

The Volkswagen Nils Concept (Figure 10.49) was designed for daily commuting, mainly competing with Audi Urban Concept and PSA VELV, first of all in terms of size: 304  139  120 cm (L  W  H). Its range is 65 km and it is powered by lithium-ion batteries that can be recharged in less than 2 h. The 20-hp electric motor weights 19 kg and has a maximum output of 34 hp, although for short times. Nils goes from 0 to 100 km/h in less than 11 s and has a maximum speed of 130 km/h. The Volkswagen Nils, whose weight is 210 kg, has an aluminum body and is characterized by gull-wing doors.

6. Conclusions EVs are entering the market, but their success will greatly depend on economic factors, i.e. the capacity of producing low-cost batteries, and on their performance, i.e. recharging time, range and reliability. The cost issue is presently uncertain. Car drivers do not want to have polluting cars any longer, but they are also unwilling to spend more than needed for a car of the same size and performance. New forms of vehicle ownership are being tested, linked to rental fees, leasing, and ownership of vehicles but not of batteries. On the performance side, criticalities include recharging times and range guaranteed by a full charge. Here the strategy is clear: battery-powered cars are destined to urban drive, and the expected range of 150–200 km per charge would be absolutely sufficient. Recharging times, however, are a big issue since, if a low-voltage outlet is used, at least 5–8 h are needed. So, battery charging must be done during long-parking times. The additional option of high-voltage quick charges must be considered, but they require adequate facilities. An alternative option is represented by the quick change of the entire battery pack in dedicated service stations, and this is the approach adopted, for instance, by the Californian Better Place in its pilot project with the Renault Nissan Group.