The low practical capacity (<140 mA h g⁻¹) of spinel phase LiMn_2−xNi_xO₄ (0 < x < 1) excludes it from high energy density lithium ion batteries (LIBs) for powering electric vehicles. Extending the operating potential window from 3.0 to 4.8 V to 2.0–4.8 V can double the capacity, but result in fast capacity decay due to the drastic cubic-tetragonal phase transition below 3.0 V, induced by serious Jahn-Teller (J-T) distortion of structure units (Mn³⁺)O₆ octahedra. Herein, we propose a novel strategy to suppress J-T distortion by tuning the linkage of structure units MnO₆ octahedra. The original full-vertex-sharing LiO₄ tetrahedra around MnO₆ octahedra in spinel phase are partially replaced by edge-sharing LiO₆ octahedra, which relate Mn-O bonds along the dz² direction with those along the d_xy plane, thus significantly mitigating J-T distortion and suppressing the phase transition when discharged to 2.0 V. Following this strategy, the prepared spinel-based cathode achieves a high reversible capacity of about 290 mA h g⁻¹ and an energy density up to 957 W h kg⁻¹ with improved cycling stability. This work finds a new opportunity for the traditional spinel cathode towards applications in high energy density LIBs in a low cost and sustainable manner.

尖晶石相 LiMn _2-x Ni _x O ₄ (0 < x < 1)的低实际容量 (<140 mA h g ^-1 )使其无法用于为电动汽车提供动力的高能量密度锂离子电池 (LIB)。将工作电位窗口从 3.0 到 4.8 V 扩展到 2.0–4.8 V 可以使容量加倍，但由于严重的 Jahn-Teller (JT) 畸变导致低于 3.0 V 的剧烈立方-四方相变导致容量快速衰减结构单元 (Mn ³⁺ )O ₆八面体。在此，我们提出了一种通过调整结构单元 MnO ₆八面体的连接来抑制 JT 失真的新策略。原版全顶点共享LiO ₄尖晶石相中MnO ₆八面体周围的四面体部分被边缘共享的LiO ₆八面体取代，其将沿dz ²方向的Mn-O键与沿d _xy平面的键联系起来，从而显着减轻了JT畸变并抑制了放电时的相变至 2.0 V。按照此策略，制备的尖晶石基正极实现了约 290 mA hg ^-1的高可逆容量和高达 957 W h kg ^-1的能量密度，并提高了循环稳定性。这项工作为传统尖晶石阴极以低成本和可持续的方式应用于高能量密度 LIB 提供了新的机会。