The irreversible loss of lithium from the cathode material during the first cycles of rechargeable Li‐ion batteries notably reduces the overall cell capacity. Here, a new family of sacrificial cathode additives based on Li₂O:Li_2/3Mn_1/3O_5/6 composites synthesized by mechanochemical alloying is reported. These nanocomposites display record (but irreversible) capacities within the Li–Mn–O systems studied, of up to 1157 mAh g⁻¹, which represents an increase of over 300% of the originally reported capacity in Li_2/3Mn_1/3O_5/6 disordered rock salts. Such a high irreversible capacity is achieved by the reaction between Li₂O and Li_2/3Mn_1/3O_5/6 during the first charge, where electrochemically active Li₂O acts as a Li⁺ donor. A 13% increase of the LiFePO₄ and LiCoO₂ first charge gravimetric capacities is demonstrated by the addition of only 2 wt% of the nanosized composite in the cathode mixture. This result shows the great potential of these newly discovered sacrificial additives to counteract initial losses of Li⁺ ions and improve battery performance.

中文翻译：

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Li2O：Li–Mn–O无序岩盐纳米复合材料作为高能量密度锂离子电池的阴极预锂化添加剂

在可充电锂离子电池的第一个循环中，锂从正极材料中不可逆转地流失会显着降低整体电池容量。在此，报道了一种新的基于机械化学合金化合成的Li ₂ O：Li _2/3 Mn _1/3 O _5/6复合材料的牺牲阴极添加剂。这些纳米复合材料在所研究的Li–Mn–O系统中显示出创纪录的（但不可逆）容量，高达1157 mAh g ^-1，这代表了最初报道的Li _2/3 Mn _1/3容量的300％以上的增长。O _5/6无序岩盐。Li ₂之间的反应实现了如此高的不可逆容量O和Li _2/3 Mn _1/3 O _5/6在第一次充电过程中，其中电化学活性Li ₂ O充当Li ⁺供体。通过在阴极混合物中仅添加2wt％的纳米尺寸复合物，证明了LiFePO ₄和LiCoO _2的第一电荷重量分析能力增加了13％。该结果表明，这些新发现的牺牲添加剂具有巨大的潜力，可抵消Li ⁺离子的初始损失并改善电池性能。