富锂锰基正极材料的聚苯胺包覆及其电化学性能

Polyaniline coating and electrochemical performance of Li-rich manganese-based cathode material

正极材料作为锂离子电池的重要组成部分之一,在一定程度上影响着电池的性能。富锂锰基正极材料Li_(1.2)Ni_(0.13)Co_(0.13)Mn_(0.54)O_(2)(LNCM)凭借高比容量、高电压等优点成为下一代锂离子电池正极材料的候选。本研究采用溶胶凝胶法制备了富锂锰基正极材料,利用原位聚合法在正极材料表面形成聚苯胺包覆层,并在聚合过程中利用质子酸掺杂进一步提高聚合物的电导率,以改善正极材料的性能。实验结果表明,X射线衍射(XRD)测试显示包覆前后正极材料的晶体结构未发生改变;傅里叶变换红外光谱分析(FT-IR)证明了复合材料中聚苯胺的存在。聚苯胺作为电子导体,可以有效降低正极材料的阻抗,提高反应动力学,稳定正极材料的晶体结构并优化其循环性能。

Anode materials,as one of the important components of lithium-ion batteries,affect the performance of the batteries to a certain extent.Lithium-rich manganese-based cathode material Li_(1.2)Ni_(0.13)Co_(0.13)Mn_(0.54)O_(2)(LNCM) has become one of the candidates for the next-generation lithium-ion battery cathode material by virtue of its high specific capacity and high voltage.In this study,lithium-rich manganese-based cathode materials were prepared by sol-gel method,and a polyaniline capping layer was formed on the surface of the cathode materials using in situ polymerization,and protonate doping was utilized to further increase the conductivity of the polymers during the polymerization process in order to improve the performance of the cathode materials.The experimental results showed that the X-ray diffraction(XRD)test showed that the crystal structure of the cathode material before and after the capping did not change;the Fourier transform infrared spectroscopy(FT-IR)analysis proved the presence of polyaniline in the composite material.As an electron conductor,polyaniline can effectively reduce the impedance of the cathode material,improve the reaction kinetics,stabilize the crystal structure of the cathode material and optimize its cycling performance.