Lithium-ion cells degrade much faster at temperatures higher than 25 °C mainly due to accelerated solid-electrolyte interface (SEI) growth in anode and degeneration of cathode [1, 2]. It is also known that temperature distributions in lithium-ion cells are not uniform [3] due to very low thermal conductivity of battery materials. The non-uniform temperature distributions could cause non-uniform degradation, thus exacerbating the thermal degradation problem, especially for large-format lithium-ion cells during high power operation. The effects of non-uniform temperature distributions on degradation of lithium-ion cells will be investigated and progress will be presented.

References

[1] C.Y. Wang, G. Zhang, S. Ge, T. Xu, Y. Ji, X.G. Yang, Y. Leng. Lithium-ion battery structure that self-heats at low temperatures, Nature, 529(7587) (2016) 515-518.

[2] T. Waldmann, M. Wilka, M. Kasper, M. Fleischhammer, M. Wohlfahrt-Mehrens. Temperature dependent ageing mechanisms in lithium-ion batteries – A post-mortem study, Journal of Power Sources, 262 (2014) 129-135.

[3] G. Zhang, L. Cao, S. Ge, C.Y. Wang, C.E. Shaffer, C.D. Rahn. In situ measurement of radial temperature distributions in cylindrical Li-ion cells, Journal of The Electrochemical Society, 161(10) (2014) A1499-A1507.