Three-volt Lithium-ion Battery of Li[Li_1/3Ti_5/3]O₄ and Li[Ni_1/2Mn_3/2]O₄ with Auxiliary Lithium Electrode to Monitor Polarization Voltages of Positive and Negative Electrodes

抄録

Three-volt lithium-ion batteries consisting of Li[Li_1/3Ti_5/3]O₄ and Li[Ni_1/2Mn_3/2]O₄ were constructed and examined in terms of their intermittent charge and discharge consisting of a 5 s current on and 15 s off at high rate (9.3 mA cm⁻²) together with the continuous charge and discharge at low rate (0.17 mA cm⁻²) for 100 cycles. To monitor the polarization voltages of the positive and negative electrodes, an auxiliary lithium electrode was placed around the electrodes in the battery. The auxiliary lithium electrode worked well for monitoring voltage balance in the battery. The continuous 100-cycle test of the battery operated in the voltage range of 1.5 to 3.5 V showed an excellent capacity retention, i.e., more than 97% of the initial capacity after 100 cycles. Based on these results, the polarization measurements of the lithium insertion electrodes are discussed, through which the electrode kinetics of the lithium insertion materials can be developed and the battery materials can also be improved for high-power applications.