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03824 Carbonaceous materials for lithium secondary battery anodes, their preparation from coal or petroleum derivatives, and same batteries
06
Electrical power supply and utilization (scientific, technical)
line and an underground cable. Finally, the simulation results are compared with those obtained from the uniform-line model used by the well-known Electromagnetic Transients Programme. Carbonaceous materials for lithium secondary 98103824 battery anodes, their preparation from coal or petroleum derivatives, and same batteries Yamaguchi, C. et al. Jpn. Kokai Tokkyo Koho JP 10 40,913 [98 40,913] (Cl. HOlM4/58), 13 Feb 1998, Appl. 96/194,503, 24 Jul 1996, 8 pp. (In Japanese) The treatment of coal or petroleum derivatives involves cross-linking, adding phosphorous compounds and firing for carbonization to give carbonaceous materials with isotropic structure. Fluorine derivatives and acid compounds can also be added with the phosphorous compounds. Preferable (1) cavity index (CI) of the carbonaceous materials and (2) form of phosphorous compounds in the carbonaceous materials are also described. Lithium batteries using the anodes are also reported. Since the phosphorous compounds, fluorine derivatives and acid compounds have cavity rate-increasing effects during carbonization of the coal or petroleum derivatives, the prepared carbonaceous materials show improved lithium adsorbency and the batteries show high discharge capacity and discharge rate. Cathode current-collectors for a novel tubular 98103825 SOFC design Hatchwell, C. E. et al. J. Power Sources, 1998, 70, (1) 85-90. For application in a novel tubular design solid oxide fuel cell (SOFC), two methods of current collection/interconnection have been developed. Nimonic 90 wires, coated with LaCoOs_h are used as the cathode currentcollectors. When compared with the uncoated Nimonic wires, the LaCoOs.h perovskite coated Nimonic wires improve the current densities of the cells. The latter is attributed to the fact that the coating improves the electrical contact between the wire and the cathode. In the second method of current collection, silver inks are painted on to the surface of the cathodes and then are achieved in comparison with the fired in situ. Greater cell performances Nimonic 90 wire systems. At 900°C and 0.7 V, with 3 cm long cathodes, a current density of 0.20 A cm -’ is achieved for cells with silver strip currentcollectors. Cation vacancy and discharge capacity of 98103826 LI[Mn2.,Li,]0., spine1 for lithium ion secondary batteries Numata, T. et al. NEC Res. Dev., 1997, 38, (3), 294-300. In order to find out the best composition in Li[Mnz_xLi,]O+ manganese spine1 with various lithium/manganese ratios were synthesized and evaluated to measure lattice constant, manganese oxidation state, true density, Tci in TGA curve and initial discharge capacity. The results indicate excess lithium ion substitutes for manganese ion in the 16d octahedral site. The existence of some vacancies in spine1 structure is suggested by the differences between theoretical and experimental values of true density and discharge capacity. It seems that a cation vacancy model seems to be more practical than an oxygen vacancy model, according to TGA curve and discharge capacity.
thermal analyses of the active materials provided information on sulfation. Electric testing data highlighted the sensitivity of cycle life performance to even a small mismatch of series connected cells under deep cycling conditions. The results support earlier work indicating the advantages of horizontal oriented cell testing and emphasize the need for closely matched cells for testing of VRLA cells. 98iO3830 The degree and effect of methanol crossover in the direct methanol fuel cell Cruickshank, J. and Scott, K. J. Power Sources, 1998, 70, (l), 40-47. The permeation of methanol from the anode to the cathode in direct methanol fuel cell (DMFC) is described in a simple model presented here. The model’s key parameters are determined with permeation rates of water and methanol through Nafion ” 117 measured under varied pressure differentials across the membrane. The effect of oxygen pressure at the cathode and methanol concentration at the anode on the measured cell voltage-current response of the DMFC can be explained by this model. 98103831 Development of small polymer electrolyte fuel cell stacks Paganin, V. A. et al. J. Power Sources, 1998, 70, (1) 55-58. Describes research and development results of small polymer electrolyte fuel cell stacks, including the assembly of single cell, 6-cell and 21-cell modules. The important characteristics of the systems are reported. A specially designed test station employing non-pressurized Hz/O2 reactants and measuring the individual and the overall cell voltage vs current under several conditions for the overall system operation, was used to test the stacks. 98iO3832 Differential scanning calorimetry material studies: implications for the safety of lithrum-ion cells Zhang, Z. et al. J. Power Sources, 1998, 70, (l), 16-20. The reactivity of materials used in lithium-ion cells can be studied via differential scanning calorimetry (DSC). In the present study, the reactivity of the three most commonly used transition metal oxides in the presence of electrolyte were investigated by DSC. The most commonly used negative electrode material, carbon (Li&,) was also studied. In the paper, relative levels of reactivity of the materials as a function of stoichiometry are reported. The implications of the results on the safety of lithium-ion cells are discussed. 98103833 Differential scanning calorimetry study of the reactivity of carbon anodes in plastic Li-ion batteries De Pasquier, A. et al. J. Electrochem. Sot., 1998, 145, (2), 472-477. Differential scanning calorimetry was used to study the chemical reactions taking place at elevated temperatures in a polymer-bonded lithiated carbon anode. The first reaction taking place at circa 120-140°C was clearly the transformation of the passivation layer products into lithium carbonate and that lithiated carbon reacted with the molten binder via dehydrofluorination only at T > 300”. The specific surface area of the electrodes and the degree of lithiation exerted a strong influence on both the reactions.
Characterization of commercially available lithium98103827 ion batteries Johnson, B. A. and White, R. A. J. Power Sources, 1998, 70, (l), 48-54. The lithium-ion battery market is experiencing aggressive growth and in response, several companies have made their version of the lithium battery commercially available. The physical design, rate, cycle-lifetime and selfdischarge performance of cells from Sony, Matsushita. A&T, Moli and Sanyo lithium-ion batteries are described in this article. A total of 85 lithium-ion cells were used from these manufacturers and all were found to perform as indicated by manufacturers’ specifications. The differences in performance and design are discussed. Performance characterization shows an excellent high discharge rate performance of the A&T and Matsushita cells, excellent cycle-lifetime performance for Sony cells, and negligible effects of self-discharge.
98103834 Effect of annealing on the hydrogen-storage properties of rapidly quenched ABs-type alloys Li, C. et al. J. Power Sources, 1998, 70, (l), 106-109. Electrochemical measurements and X-ray diffraction were employed to examine the effect of annealing on the hydrogen-storage properties of rapidly quenched ABs-type alloys. At an appropriate temperature, annealing can give a promising alloy with large capacity, high discharge voltage and long cycle life. If the temperature is too high, however (800°C) annealing results in the largest discharge capacity, but the worst cycle life. Annealing can also flatten the discharge plateau regions. The striking difference in the phase structure between as-quenched and as-annealed alloys is that new phases occur as the product of annealing at high temperatures such as 600 and 800°C. These phases are responsible for the deterioration in cycle durability.
Coke-graphite anodes for lithium secondary 98103828 batteries Kojima, Y. ef al. Jpn. Kokai Tokkyo Koho JP 10 83,808 [98 83,808] (Cl. HOlM4/02), 31 Mar 1998, Appl. 96/262,503, 10 Sep 1996, 6 pp. (In Japanese) Active masses containing 60-98% coke and 2-40% graphite are used in the lithium-absorbing anodes and provide the batteries with high chargedischarge capacity.
93/03835 Effect of silicate and phosphate additives on the kinetics of the oxygen evolution reaction in valve-regulated lead/acid batteries Vinod, M. P. er al. J. Power Sources, 1998, 70, (1) 103-105. For application in valve-regulated lead/acid batteries, a study into the effect of sodium silicate and phosphoric acid additives on the kinetics of oxygen evolution on PbOz electrodes in sulfuric acid has been conducted in gelled and flooded electrolytes. A comparison of the open-circuit potential versus time transients, with and without these additives, indicates that the additives suppress self-discharge of the electrodes. Tafel polarization studies also suggest that the addition of phosphoric acid attenuates the rate of oxygen evolution reaction. Cyclic voltammetric data supports this data.
Comments on the evaluation of valve regulated 93iO3829 lead-acid battertes (VRLA) under deep cycling regimes Cannone, A. G. et al. Annu. Battery Conf. Appl. Adv., 13th, 1998, 271-278. and Edited by Frank, H. A. and See, E. T., Institute of Electrical Electronics Engineers, New York, NY. The evaluation of components, orientation, and materials for recombinant valve regulated lead-acid batteries is challenging. An appropriate charging regime is critical to the meaningful evaluation of materials, designs and applications. Discharge capacity, impedance, weight loss, open circuit voltage after float, effects of stack compression and variations of charging regime were measured in the study. Tear-down analysis of cells provided information on electrolyte distribution and concentration and chemical and
353
Fuel and Energy Abstracts
September
1998
98iO3838 An efficient fuzzy controlled system for superconducting magnetic energy storage unit Rabbani, M. G. et al. Electrical Power & Energy Systems, 1998, 20, (3), 197202. It is essential for superconducting magnetic energy storage (SMES) controllers to be capable of providing appropriate stabilizing signals to the power system over a broad range of operating conditions and
Electrical power supply and utilization (scientific, technical)
line and an underground cable. Finally, the simulation results are compared with those obtained from the uniform-line model used by the well-known Electromagnetic Transients Programme. Carbonaceous materials for lithium secondary 98103824 battery anodes, their preparation from coal or petroleum derivatives, and same batteries Yamaguchi, C. et al. Jpn. Kokai Tokkyo Koho JP 10 40,913 [98 40,913] (Cl. HOlM4/58), 13 Feb 1998, Appl. 96/194,503, 24 Jul 1996, 8 pp. (In Japanese) The treatment of coal or petroleum derivatives involves cross-linking, adding phosphorous compounds and firing for carbonization to give carbonaceous materials with isotropic structure. Fluorine derivatives and acid compounds can also be added with the phosphorous compounds. Preferable (1) cavity index (CI) of the carbonaceous materials and (2) form of phosphorous compounds in the carbonaceous materials are also described. Lithium batteries using the anodes are also reported. Since the phosphorous compounds, fluorine derivatives and acid compounds have cavity rate-increasing effects during carbonization of the coal or petroleum derivatives, the prepared carbonaceous materials show improved lithium adsorbency and the batteries show high discharge capacity and discharge rate. Cathode current-collectors for a novel tubular 98103825 SOFC design Hatchwell, C. E. et al. J. Power Sources, 1998, 70, (1) 85-90. For application in a novel tubular design solid oxide fuel cell (SOFC), two methods of current collection/interconnection have been developed. Nimonic 90 wires, coated with LaCoOs_h are used as the cathode currentcollectors. When compared with the uncoated Nimonic wires, the LaCoOs.h perovskite coated Nimonic wires improve the current densities of the cells. The latter is attributed to the fact that the coating improves the electrical contact between the wire and the cathode. In the second method of current collection, silver inks are painted on to the surface of the cathodes and then are achieved in comparison with the fired in situ. Greater cell performances Nimonic 90 wire systems. At 900°C and 0.7 V, with 3 cm long cathodes, a current density of 0.20 A cm -’ is achieved for cells with silver strip currentcollectors. Cation vacancy and discharge capacity of 98103826 LI[Mn2.,Li,]0., spine1 for lithium ion secondary batteries Numata, T. et al. NEC Res. Dev., 1997, 38, (3), 294-300. In order to find out the best composition in Li[Mnz_xLi,]O+ manganese spine1 with various lithium/manganese ratios were synthesized and evaluated to measure lattice constant, manganese oxidation state, true density, Tci in TGA curve and initial discharge capacity. The results indicate excess lithium ion substitutes for manganese ion in the 16d octahedral site. The existence of some vacancies in spine1 structure is suggested by the differences between theoretical and experimental values of true density and discharge capacity. It seems that a cation vacancy model seems to be more practical than an oxygen vacancy model, according to TGA curve and discharge capacity.
thermal analyses of the active materials provided information on sulfation. Electric testing data highlighted the sensitivity of cycle life performance to even a small mismatch of series connected cells under deep cycling conditions. The results support earlier work indicating the advantages of horizontal oriented cell testing and emphasize the need for closely matched cells for testing of VRLA cells. 98iO3830 The degree and effect of methanol crossover in the direct methanol fuel cell Cruickshank, J. and Scott, K. J. Power Sources, 1998, 70, (l), 40-47. The permeation of methanol from the anode to the cathode in direct methanol fuel cell (DMFC) is described in a simple model presented here. The model’s key parameters are determined with permeation rates of water and methanol through Nafion ” 117 measured under varied pressure differentials across the membrane. The effect of oxygen pressure at the cathode and methanol concentration at the anode on the measured cell voltage-current response of the DMFC can be explained by this model. 98103831 Development of small polymer electrolyte fuel cell stacks Paganin, V. A. et al. J. Power Sources, 1998, 70, (1) 55-58. Describes research and development results of small polymer electrolyte fuel cell stacks, including the assembly of single cell, 6-cell and 21-cell modules. The important characteristics of the systems are reported. A specially designed test station employing non-pressurized Hz/O2 reactants and measuring the individual and the overall cell voltage vs current under several conditions for the overall system operation, was used to test the stacks. 98iO3832 Differential scanning calorimetry material studies: implications for the safety of lithrum-ion cells Zhang, Z. et al. J. Power Sources, 1998, 70, (l), 16-20. The reactivity of materials used in lithium-ion cells can be studied via differential scanning calorimetry (DSC). In the present study, the reactivity of the three most commonly used transition metal oxides in the presence of electrolyte were investigated by DSC. The most commonly used negative electrode material, carbon (Li&,) was also studied. In the paper, relative levels of reactivity of the materials as a function of stoichiometry are reported. The implications of the results on the safety of lithium-ion cells are discussed. 98103833 Differential scanning calorimetry study of the reactivity of carbon anodes in plastic Li-ion batteries De Pasquier, A. et al. J. Electrochem. Sot., 1998, 145, (2), 472-477. Differential scanning calorimetry was used to study the chemical reactions taking place at elevated temperatures in a polymer-bonded lithiated carbon anode. The first reaction taking place at circa 120-140°C was clearly the transformation of the passivation layer products into lithium carbonate and that lithiated carbon reacted with the molten binder via dehydrofluorination only at T > 300”. The specific surface area of the electrodes and the degree of lithiation exerted a strong influence on both the reactions.
Characterization of commercially available lithium98103827 ion batteries Johnson, B. A. and White, R. A. J. Power Sources, 1998, 70, (l), 48-54. The lithium-ion battery market is experiencing aggressive growth and in response, several companies have made their version of the lithium battery commercially available. The physical design, rate, cycle-lifetime and selfdischarge performance of cells from Sony, Matsushita. A&T, Moli and Sanyo lithium-ion batteries are described in this article. A total of 85 lithium-ion cells were used from these manufacturers and all were found to perform as indicated by manufacturers’ specifications. The differences in performance and design are discussed. Performance characterization shows an excellent high discharge rate performance of the A&T and Matsushita cells, excellent cycle-lifetime performance for Sony cells, and negligible effects of self-discharge.
98103834 Effect of annealing on the hydrogen-storage properties of rapidly quenched ABs-type alloys Li, C. et al. J. Power Sources, 1998, 70, (l), 106-109. Electrochemical measurements and X-ray diffraction were employed to examine the effect of annealing on the hydrogen-storage properties of rapidly quenched ABs-type alloys. At an appropriate temperature, annealing can give a promising alloy with large capacity, high discharge voltage and long cycle life. If the temperature is too high, however (800°C) annealing results in the largest discharge capacity, but the worst cycle life. Annealing can also flatten the discharge plateau regions. The striking difference in the phase structure between as-quenched and as-annealed alloys is that new phases occur as the product of annealing at high temperatures such as 600 and 800°C. These phases are responsible for the deterioration in cycle durability.
Coke-graphite anodes for lithium secondary 98103828 batteries Kojima, Y. ef al. Jpn. Kokai Tokkyo Koho JP 10 83,808 [98 83,808] (Cl. HOlM4/02), 31 Mar 1998, Appl. 96/262,503, 10 Sep 1996, 6 pp. (In Japanese) Active masses containing 60-98% coke and 2-40% graphite are used in the lithium-absorbing anodes and provide the batteries with high chargedischarge capacity.
93/03835 Effect of silicate and phosphate additives on the kinetics of the oxygen evolution reaction in valve-regulated lead/acid batteries Vinod, M. P. er al. J. Power Sources, 1998, 70, (1) 103-105. For application in valve-regulated lead/acid batteries, a study into the effect of sodium silicate and phosphoric acid additives on the kinetics of oxygen evolution on PbOz electrodes in sulfuric acid has been conducted in gelled and flooded electrolytes. A comparison of the open-circuit potential versus time transients, with and without these additives, indicates that the additives suppress self-discharge of the electrodes. Tafel polarization studies also suggest that the addition of phosphoric acid attenuates the rate of oxygen evolution reaction. Cyclic voltammetric data supports this data.
Comments on the evaluation of valve regulated 93iO3829 lead-acid battertes (VRLA) under deep cycling regimes Cannone, A. G. et al. Annu. Battery Conf. Appl. Adv., 13th, 1998, 271-278. and Edited by Frank, H. A. and See, E. T., Institute of Electrical Electronics Engineers, New York, NY. The evaluation of components, orientation, and materials for recombinant valve regulated lead-acid batteries is challenging. An appropriate charging regime is critical to the meaningful evaluation of materials, designs and applications. Discharge capacity, impedance, weight loss, open circuit voltage after float, effects of stack compression and variations of charging regime were measured in the study. Tear-down analysis of cells provided information on electrolyte distribution and concentration and chemical and
353
Fuel and Energy Abstracts
September
1998
98iO3838 An efficient fuzzy controlled system for superconducting magnetic energy storage unit Rabbani, M. G. et al. Electrical Power & Energy Systems, 1998, 20, (3), 197202. It is essential for superconducting magnetic energy storage (SMES) controllers to be capable of providing appropriate stabilizing signals to the power system over a broad range of operating conditions and