The low initial Coulombic efficiency of anodes such as Si@C can seriously affect the capacity of high-energy-density Li-ion batteries (LIBs). Supplement the initial irreversible lithium loss in the anode through prelithiation technology is the only way to realize the next generation of LIBs. In this work, we report the study of Al–Li alloy (ALA) as a prelithiation additive for LIBs cathodes. As a bifunctional sacrificial lithium source, ALA can not only provide an additional capacity of 1068 mAhg⁻¹ to supplement the initial active lithium consumption, but also form aluminum and aluminum oxide to stabilize the cathode interface after the delithiation to improve the battery cycling stability. Therefore, the initial charge capacity of LiCoO₂ (LCO) and LiNi_0.6Co_0.2Mn_0.2O₂ (NCM622) electrodes can be increased to 12.5%–18.5% by adding 2%–4% ALA. In addition, the energy density of the NCM811/Si@C pouch cell prelithiated by ALA can reach 541 Wh kg⁻¹, which means that the cathode can maximize the capacity (from 189 mAh g⁻¹ to 205 mAh g⁻¹). In conclusion, this work develops a more inexpensive and efficient cathode prelithiation additive for next-generation LIBs.

Si@C等负极的低初始库仑效率会严重影响高能量密度锂离子电池（LIB）的容量。通过预锂化技术补充负极初始不可逆的锂损失是实现下一代锂离子电池的唯一途径。在这项工作中，我们报告了铝锂合金（ALA）作为锂离子电池正极的预锂化添加剂的研究。作为双功能牺牲锂源，ALA不仅可以提供1068 mAhg ^-1的额外容量来补充初始活性锂消耗，而且在脱锂后形成铝和氧化铝稳定正极界面，提高电池循环稳定性。因此，LiCoO ₂ (LCO)和LiNi _0.6 Co的初始充电容量_0.2 Mn _0.2 O ₂ (NCM622)电极加入2%~4% ALA可提高到12.5%~18.5%。此外，ALA预锂化的NCM811/Si@C软包电池的能量密度可以达到541 Wh kg ^-1，这意味着正极可以最大化容量（从189 mAh g ^-1到205 mAh g ^-1）。总之，这项工作为下一代 LIB 开发了一种更便宜、更有效的正极预锂化添加剂。