离子液体PP13TFSI在锂离子电池中的应用

Application of ionic liquid PP13TFSI in Li-ion battery

用离子液体N-甲基-N-丙基哌啶二(三氟甲基磺酰)亚胺(PP13TFSI)和有机溶剂碳酸乙烯酯(EC)、碳酸二甲酯(DMC),制备了1 mol/L LiPF6/PP13TFSI+EC+DMC混合电解液。热重分析(TG)结果表明:PP13TFSI的添加减少了有机溶剂的挥发,PP13TFSI体积含量越高,相同温度下混合电解液的质量损失率越低。当PP13TFSI的含量不低于40%时,混合电解液不燃烧。以0.05C在2.5～4.2 V循环,使用1 mol/L LiPF6/20%PP13TFSI+80%[EC+DMC(体积比1∶1)]混合电解液的Li/LiNi0.7Co0.15Mn0.15O2电池,首次放电比容量为183.8 mAh/g,高于使用纯有机溶剂电解液的电池。

Mixed electrolyte 1 mol/L LiPF6/N-methyl-N-propylpiperidinium his （trifluoromethanesulfonyl） imide （PP13TFSI） ＋ ethylene carbonate（EC） ＋ dimethylene carbonate（DMC） was prepared using ionic liquid PP13TFSI and organic solvent EC, DMC. The results of thermogravimetric（TG） analysis indicated that the adding of PP13TFSI restrained the volatilization of orga-nic solvent,as increased the volume content of PP13TFSI, at the same temperature, the weight loss of the mixed electrolyte was less. When the eontent of PP13TFSI was no less than 40%, the mixed electrolyte was nonflammable. When cycled with 0.05 C in 2.5 - 4.2 V, the initial specific discharge capacity of Li/LiNi0.TCo0A5 MnA0.15O2 cell using 1 mol/L LiPF6/20% PP13TFSI ＋ 80% [EC ＋ DMC（ 1：1 ,vol）]mixed electrolyte was 183.8 mAh/g, whieh was higher than the pure organic electrolyte one.