LiFSI/LiPF6混盐电解液对高镍/硅碳电池性能的影响OA

To investigate the mechanism of action of mixed salt systems on the performance of high-nickel/silicon-carbon batteries,lithium bis(fluorosulfonyl)imide(LiFSI)was used as the main salt,and lithium hexafluorophosphate(LiPF6)as the auxiliary salt to inhibit aluminum foil corrosion.The physicochemical properties of electrolytes with different LiFSI/LiPF₆ ratios,as well as their effects on the rate capability and high-temperature(55℃)cycling stability of the batteries,were systematically studied.Aluminum foil corrosion characterization indicates that the introduction of LiPF₆ can effec-tively suppress aluminum foil corrosion,while cyclic voltammetry(CV)tests reveal a positive correla-tion between the degree of aluminum foil corrosion and LiFSI content.Electrochemical test results demonstrate that the optimized mixed salt ratio can synergistically enhance the rate capability and high-temperature cycling stability of the batteries.When the molar ratio of LiPF₆ to LiFSI is 1∶1,the battery exhibits the minimum gas evolution,the best cycling performance,and the lowest internal re-sistance change rate after cycling at 55℃,retaining 80%of its initial capacity after 370 cycles at 0.5 C/0.5 C.Precise regulation of the LiFSI/LiPF6 ratio can significantly mitigate aluminum foil corrosion and capacity fading during high-temperature cycling,providing key experimental basis and technical reference for the electrolyte formulation optimization of high-nickel/silicon-carbon batteries.