Abstract In this current work, high-voltage spinel LiNi0.5Mn1.5O4 (LNMO) decorated with AlF3 thin layer was successfully synthesized and investigated for the application in Li-ion batteries (LIBs). The electrochemical properties and dissolution behavior of transition metals of the AlF3-modified LNMO electrodes were investigated, especially at elevated temperature. The well-defined and homogeneous AlF3 coating on the surface of LNMO was conducted by a facile chemical modification approach, in which the thickness of AlF3 modification layer was adjusted by adjusting the AlF3 precursor concentrations. After the optimization of the AlF3 precursor concentration, the 1 wt% AlF3-modified LNMO electrode revealed the remarkably improved cyclability especially at elevated temperature. The 1 wt% AlF3-modified LNMO electrode displayed an impressive capacity retention up to 81.7% after charged/discharged at 0.2C at elevated temperature for 100 cycles, which was superior to that of the pristine LNMO electrode (70.1%). Its improved cyclability can be ascribed to the efficient suppression of electrolyte decomposition reaction and transition metal dissolution, thus signaling promising potential in high-voltage LIBs applications.

中文翻译：

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锂离子电池用AlF3改性尖晶石LiNi0.5Mn1.5O4正极高温循环性能的提高

摘要 在目前的工作中，成功合成了装饰有 AlF3 薄层的高压尖晶石 LiNi0.5Mn1.5O4 (LNMO) 并研究了其在锂离子电池 (LIBs) 中的应用。研究了 AlF3 修饰的 LNMO 电极的过渡金属的电化学性质和溶解行为，特别是在升高的温度下。通过简单的化学改性方法在 LNMO 表面上定义明确且均匀的 AlF3 涂层，其中通过调整 AlF3 前驱体浓度来调整 AlF3 改性层的厚度。在优化 AlF3 前体浓度后，1 wt% AlF3 修饰的 LNMO 电极显示出显着改善的循环性能，尤其是在高温下。1 wt% AlF3 改性的 LNMO 电极在 0.2C 高温下充放电 100 次循环后显示出令人印象深刻的容量保持率，高达 81.7%，优于原始 LNMO 电极（70.1%）。其改善的循环性可归因于有效抑制电解质分解反应和过渡金属溶解，从而在高压LIBs应用中显示出广阔的潜力。