Solid-state electrolytes with high ionic conductivities are crucial for the development of all-solid-state lithium batteries, and there is a strong correlation between the ionic conductivities and underlying lattice structures of solid-state electrolytes. Here, we report a lattice manipulation method of replacing [Li₂OH]⁺ clusters with potassium ions in antiperovskite solid-state electrolyte (Li₂OH)_0.99K_0.01Cl, which leads to a remarkable increase in ionic conductivity (4.5 × 10^‒3 mS cm^‒1, 25 °C). Mechanistic analysis indicates that the lattice manipulation method leads to the stabilization of the cubic phase and lattice contraction for the antiperovskite, and causes significant changes in Li-ion transport trajectories and migration barriers. Also, the Li||LiFePO₄ all-solid-state battery (excess Li and loading of 1.78 mg cm^‒2 for LiFePO₄) employing (Li₂OH)_0.99K_0.01Cl electrolyte delivers a specific capacity of 116.4 mAh g^‒1 at the 150th cycle with a capacity retention of 96.1% at 80 mA g^‒1 and 120 °C, which indicates potential application prospects of antiperovskite electrolyte in all-solid-state lithium batteries.

具有高离子电导率的固态电解质对于全固态锂电池的发展至关重要，并且固态电解质的离子电导率与底层晶格结构之间存在很强的相关性。在这里，我们报告了一种在反钙钛矿固态电解质（Li ₂ OH） _0.99 K _0.01 Cl中用钾离子取代[Li ₂ OH] ⁺簇的晶格操纵方法，这导致离子电导率显着增加（4.5 × 10 ^{− 3} mS cm ^–1 , 25 °C)。机理分析表明，晶格操纵方法导致反钙钛矿立方相的稳定和晶格收缩，并引起锂离子传输轨迹和迁移势垒的显着变化。此外，采用(Li ₂ OH) _0.99 K _0.01 Cl电解质的Li||LiFePO ₄全固态电池（LiFePO ₄过量Li且负载量为1.78 mg cm ⁻² ）的比容量为116.4 mAh g ⁻¹在80 mA g ^-1和120 °C下第150次循环时容量保持率为96.1%，这表明反钙钛矿电解质在全固态锂电池中的潜在应用前景。