Lifetime Cycle Deterioration Analysis of Li-ion Battery by AC Impedance Response: Applied to Life Cycle Experience of Energy Storage for Marine Uses

摘要

Lithium ion battery is major energy storage which has chemical degradation with lifetime cycles. The previous report was focused on Lithium ion (Li-ion) battery, to which cyclic load was applied and begun to investigate the lifetime cycle deterioration and the result showed that the Li-ion battery electrolyte resistance was increased, and the battery electrode surface impedance which is attributed to parallel combination of Faradaic impedance and double-layer capacitance were also increased in progress of cycles. This study reports the other experimental results and applies the AC impedance response analysis to verify the battery deterioration. The Li-ion battery electrolyte resistance was increased with cycles which was the same response as Ni-MH battery of AB5 type electrode structure. The battery electrode surface impedance was not increased with cycles. The result did not verify the growth of solid electrolyte interface (SEI) layer which covers over the battery negative electrode where SEI layer has been assumed to grow along with cycles. The charge transfer resistance was affected from SEI layer of which stacking status may not be uniform with the cycle increase. The charge transfer resistance was about one fifth level to the liquid electrolyte resistance which was less effective to the overall battery real part impedance, the charge transfer resistance does not provide the co-relation of impedance increase with the cycle increase.