Unrevealing the effects of low temperature on cycling life of 21700-type cylindrical Li-ion batteries

• 作者: Daozhong Hu Gang Chen Jun Tian Ning Li Lai Chen Yuefeng Su Tinglu Song Yun Lu Duanyun Cao Shi Chen Feng Wu
• 来源期刊: 能源化学
• 年，卷（期）: 2021,（9）
• 页码范围: 104-110
• 页数: 7页
• 语种: 英文

摘要

The low-temperature performance of Li-ion batteries(LIBs)has important impacts on their commercial applications.Besides the metallic lithium deposition,which is regarded as one of the main failure mech-anisms of the LIBs at low temperatures,the synergistic effects originating from the cathode,anode,elec-trolyte,and separators to the batteries are still not clear.Here,the 21700-type cylindrical batteries were evaluated at a wide range of temperatures to investigate the failure mechanism of batteries.Voltage relaxation,and the post-mortem analysis combined with the electrochemical tests,unravel that the capacity degradation of batteries at low temperature is related to the lithium plating at graphite anodes,the formation of unsatisfied solid deposited/decomposed electrolyte mixture phase on the anode,the precipitation of solvent in the electrolytes and the block of separator pores,and the uneven dissolved transition metal-ions from the cathode.We hope this finding may open up a new avenue to alleviate the capacity degradation of advanced LIBs at low temperatures and shed light on the development of out-standing low-temperature LIBs via simultaneous optimization of all the components including elec-trodes,electrolytes and separators.