海藻酸钠/聚丙烯酸粘结剂在富锂锰基正极中的研究

Research on sodium alginate/polyacrylic acid binder in Li-rich layered oxide cathodes

水性工艺制备电极具有成本低、环保等优点,在锂离子电池工业中具有广泛的应用前景。通过海藻酸钠(SA)和聚丙烯酸(PAA)制备出适用于富锂锰基正极(LLOs)水性工艺的复合粘结剂。结果表明,调节SA和PAA质量比可以控制SA的羟基与PAA的羧基的交联程度,从而调控电极结构,改善电极动力学。当SA/PAA质量比为3∶1时,使用水性工艺制备的LLOs正极电极具有优异的电化学性能。基于该电极的LLOs‖锂半电池具有293.8 mAh/g(4.8 V)的放电比容量,在3 C下具有179.2 mAh/g的放电比容量。该研究结果将有助于设计和优化用于4.8 V高压LLOs的粘结剂。

Owning to the low cost and eco-friendliness,water-based processing for the preparation of electrode films is attractive in Li-ion battery industry.A composite binder suitable for water-based processing of Li-rich layered oxide cathodes(LLOs)was prepared by sodium alginate(SA)and polyacrylic acid(PAA).The result demonstrats that adjusting the mass ratio of SA and PAA can control the degree of cross-linking between the hydroxyl group of SA and the carboxyl group of PAA,thus regulating the electrode structure and improving the electrode kinetics.The LLOs electrode films prepared by the water-based processing has excellent electrochemical performance when the mass ratio of SA/PAA is 3∶1.The LLOs‖Li half-cells have a discharge specific capacity of 293.8 mAh/g(4.8 V),and 179.2 mAh/g at a high current density of 3 C.The study will help to design and optimize binders for 4.8 V high voltage LLOs.