Lithium ion batteries(LIBs)with silicon-carbon anode will experience significant volume expansion during the charging and discharging process,and as the aging state of the battery intensifies,the continuous accumulation of irreversible expansion will trigger a series of safety issues.Here we investigate the volume expansion and capacity degradation of two LIBs with different silicon-content silicon-carbon anode under long cycles.It is found that the higher the silicon content,the more obvious the accumulation of side reaction products inside the LIB,which leads to a significant increase of the volume expansion and accelerates the capacity degradation.In addition,cyclic testing of the same group LIBs under different external pressures shows that the capacity degradation rate is the slowest during cycling in the external pressure range of 50-100kg.This also provides researchers with ideas for improving the cycle life of LIBs with silicon-carbon anode.
关键词
锂离子电池/硅碳负极/外压力/体积膨胀/容量衰减
Key words
Lithium ion Batteries/Silicon-Carbon Anode/External Pressure/Volume Expansion/Capacity Degradation
维普
万方数据