聚醚型硅氧烷改性丙烯酸聚合物制备与性能研究

Application of Polyether Siloxane Modified Acrylic Polymer in Lithium-ion Battery

采用聚乙二醇350单甲醚(m PEG 350)、乙烯基三甲氧基硅烷(KH 171)、丙烯酸(AA)为结构单体,通过“两步法”制备了一种新型聚合物粘结剂聚醚型硅氧烷改性丙烯酸聚合物(PSA)用作锂离子电池粘结剂。红外证实了PSA的成功合成,拉伸、剥离以及纳米压痕测试结果表明,PSA的断裂伸长率为181%、制备的电极最大剥离力为17.1 N、纳米压痕回弹率为53.36%。电化学测试结果表明,组装的电池循环80圈后的库伦效率在90%以上,经过高倍率循环后低倍率下的可逆容量为原始的90%左右,并且电极在循环中形成了薄而稳定的SEI层,电极整体性保持良好。

The polyether-type siloxane modified acrylic polymer(PSA) was prepared by "two-step" method as a lithium-ion battery binder, where polyethylene glycol 350 monomethyl ether(mPEG 350), vinyl trimethoxysilane(KH 171) and acrylic acid(AA) were used as monomers. The product PSA was confirmed by infrared. Through the characterization including tensile, peeling and nanoindentation tests, it shows that the elongation at break of PSA is 181%, the maximum peeling force of the electrode is 17.1 N, and the rebound rate of nanoindentation is 53.36%. Finally, the electrochemical test was carry out. The coulombic efficiency of the assembled cell is above 90% after 80 cycles. The reversible capacity under low magnification after the high magnification cycle is about 90% of the original. The electrode formed a thin and stable SEI layer in the cycle, and the integrity of the electrode is maintained well.