分散剂在正极材料磷酸铁锂中的应用

Application of dispersants in cathode material lithium iron phosphate

分别将十二烷基磺酸钠(SDS)和聚乙二醇(PEG)用作锂离子电池正极水性合膏工艺的分散剂。用交流阻抗、循环伏安和充放电测试,研究了它们对磷酸铁锂(LiFePO4)性能的影响。经20次不同倍率的循环,当分散剂SDS的含量为0.6%时,电池的比容量为87.82 mAh/g,容量保持率为63.3%;当分散剂PEG的含量为0.4%时,电池的比容量由0.20C时的143.61 mAh/g降至2.00C时的107.14 mAh/g,容量保持率为74.6%,循环稳定性和大电流性能较好。

Sodium dodecyl sulfate （SDS） and polyethylene glycol （PEG） were used as dispersant in the water paste technology of Li-ion battery cathode. Their effects on the performance of lithium iron phosphate （LiFePO4） were studied by the tests of AC impedance, cyclic vohammetry and charge-discharge. When the content of dispersant SDS was 0.6%, the specific capacity of bat- tery was improved, the cycle performance was stable. After 20 cycles with different rates, the specific capacity of battery was 87.82 mAh/g, the capacity retention rate reached to 63.3%. When the content of dispersant PEG was 0.4%, after 20 cycles with different rates, the specific capacity of battery decreased from 143.61 mAh/g of 0.20 C to 107.14 mAh/g of 2.00 C, the capacity retention rate was 74.6%, the cycle stability and large current performance were fine.