涂胶隔膜对锂离子电池性能的影响

Effect of adhesive-coated separator on performance of Li-ion battery

以3 Ah软包装动力锂离子电池为研究对象,考察喷涂和辊涂水系涂胶(聚偏氟乙烯及其共聚物)隔膜对电池性能的影响。水系喷涂涂胶隔膜电池具有较低的分容内阻和脉冲充放电直流内阻(DCR)。以不低于2.00 C倍率在2.50~4.25 V充放电,与辊涂涂胶隔膜电池相比,喷涂涂胶隔膜电池的倍率充电恒流充入比高约1%,倍率放电容量比高约0.2%,-20℃放电容量与25℃的容量比低3%以上。25℃和45℃下循环1000次,两种涂胶隔膜性能差异较小;在25℃循环超过1000次,喷涂涂胶隔膜电池性能稍好,循环2000次的容量保持率高约1.7%。

The effect of spraying and roller coating water-based adhesive-coated(polyvinylidene fluoride and its copolymers)separator on the performance of 3 Ah pouch power Li-ion battery is investigated.The spraying water-based adhesive-coated separator battery has a lower capacitance internal resistance and pulse charge and discharge direct current resistance(DCR).When charging and discharging in 2.50-4.25 V at a rate of not less than 2.00 C,compared with the roller coating adhesive-coated separator battery,the rate charge constant current charging ratio of the spraying adhesive-coated separator battery is about 1%higher,the rate discharge capacity ratio is about 0.2%higher and the ratio of discharge capacity at-20℃to the capacity at 25℃is more than 3%lower.After 1000 cycles at 25℃and 45℃,there is little difference in the performance of the two adhesive-coated separators.After more than 1000 cycles at 25℃,the performance of the spraying adhesive-coated separator battery is slightly better,the capacity retention rate is about 1.7%higher after 2000 cycles.