Antimony (Sb) is an attractive cathode for liquid metal batteries (LMBs) because of its high theoretical voltage and low cost. The main obstacles associated with the Sb-based cathodes are unsatisfactory energy density and poor rate-capability. Herein, we propose a novel Sb₆₄Cu₃₆ cathode that effectively tackles these issues. The Sb₆₄Cu₃₆ (melting point: 525 °C) cathode presents a novel lithiation mechanism involving sequentially the generation of Li₂CuSb, the formation of Li₃Sb, and the conversion reaction of Li₂CuSb to Li₃Sb and Cu. The generated intermetallic compounds show a unique microstructure of the upper floated Li₂CuSb layer and the below cross-linked structure with interpenetrated Li₂CuSb and Li₃Sb phases. Compared with Li₃Sb, the lower Li migration energy barrier (0.188 eV) of Li₂CuSb significantly facilitates the lithium diffusion across the intermediate compounds and accelerates the reaction kinetics. Consequently, the Li||Sb₆₄Cu₃₆ cell delivers a more excellent electrochemical performance (energy density: 353 W h kg⁻¹ at 0.4 A cm⁻²; rate capability: 0.59 V at 2.0 A cm⁻²), and a much lower energy storage cost of only 38.45 $ kW h⁻¹ than other previously reported Sb-based LMBs. This work provides a novel cathode design concept for the development of high-performance LMBs in applications for large-scale energy storage.

锑 (Sb) 是液态金属电池 (LMB) 的理想阴极，因为它具有高理论电压和低成本。与锑基正极相关的主要障碍是能量密度不令人满意和倍率能力差。在此，我们提出了一种有效解决这些问题的新型 Sb ₆₄ Cu _36阴极。Sb ₆₄ Cu ₃₆（熔点：525 °C）正极呈现出一种新型锂化机制，依次涉及 Li ₂ CuSb 的生成、Li 3 Sb 的形成以及_{Li 2} CuSb 向 Li ₃ Sb 和 Cu的转化反应。生成的金属间化合物显示出上层浮锂的独特微观结构₂ CuSb 层和下面的交联结构具有互穿的 Li ₂ CuSb 和 Li ₃ Sb 相。与 Li _{3 Sb 相比，Li 2} CuSb较低的锂迁移能垒 (0.188 eV)显着促进了锂在中间化合物中的扩散并加速了反应动力学。因此，Li||Sb ₆₄ Cu ₃₆电池具有更优异的电化学性能（能量密度：353 W h kg ^-1 at 0.4 A cm ^-2；倍率能力：0.59 V at 2.0 A cm ^-2），以及更多更低的储能成本仅为 38.45 $ kW h ⁻¹比以前报道的其他基于 Sb 的 LMBs。这项工作为在大规模储能应用中开发高性能 LMB 提供了一种新颖的阴极设计理念。