改善锂离子电池的低温充电性能

通过优选电池材料,提高锂离子电池的低温充电性能。与常规材料相比,采用二次颗粒石墨(一次、二次粒子的D_(50)分别为9~10μm和15~17μm)、水溶性粘合剂LA132和添加乙酸丙酯(PA)的低温型电解液,可提高电池的低温充电性能。负极采用95.5%二次颗粒石墨、1.0%导电剂和3.5%水溶性粘合剂LA132,电解液含有低温溶剂时,可达到最优效果。在-5℃、-10℃、-15℃和-20℃低温条件下,电池以0.15 C电流进行恒流充电,Li~+不可逆损耗比例分别为0.01%、0.03%、1.01%和1.35%,负极片表面均未出现析锂现象。

Improving the low-temperature charging performance of Li-ion battery

The low-temperature charging performance of Li-ion battery was improved by optimizing the battery materials.Compared to the normal materials,the low-temperature charging performance of the battery was improved by using secondary particulate graphite (the D50 of the first and secondary particulate were 9-10 μm and 15-17 μm,respectively),aqueous binder LA132 and low-temperature electrolyte added propy acetate (PA).The result was best when 95.5％ secondary particulate graphite,1.0％ conductive agent and 3.5％ aqueous binder LA132 were used in the anode,and electrolyte contained low-temperature solvent.When the battery was galvanostatic charged with 0.15 C at the low temperature of-5 ℃,-10 ℃,-15 ℃ and-20 ℃,the ratio of Li+ irreversible loss was 0.01％,0.03％,1.01％ and 1.35％,respectively.There were no lithium dendrites on the anode surface.