Publication date: 15th December 2025
Liquid metal batteries (LMBs) have emerged as promising candidates for grid-scale energy storage due to their intrinsic advantages of low cost, long lifespan, inherent safety, and straightforward, scalable architecture. However, their rate performance is often limited by the formation of dense solid intermetallic compounds during discharge, which hinder ion transport and induce large polarization. To overcome these kinetic constraints, recent studies have focused on interface engineering using alloyed positive electrodes. Networked liquid pathways constructed through alloying—such as Bi–Sn, Bi–Cd, and Bi–Cu systems—significantly enhance electrochemical kinetics by improving ionic diffusivity, increasing electrical conductivity, and lowering diffusion energy barriers. These strategies enable higher reaction stoichiometry, reduced polarization, and improved adaptability to lower operating temperatures. As a result, LMBs incorporating such engineered alloy cathodes demonstrate outstanding performance, including high energy efficiency (>91%), excellent high-rate capability (up to 3–3.4 C with >80% capacity retention), stable cycling over hundreds to thousands of cycles, and competitive system-level cost. Collectively, these advances highlight the critical role of interface-guided alloy architecture design in unlocking fast-kinetic, durable, and scalable LMBs, offering a powerful pathway toward practical large-scale energy storage deployment.
This work is supported by the National Key Research and Development Program of China (2024YFB2408300), and National Natural Science Foundation of China (52374310, 92372205, 51874228). The author gratefully acknowledges the support of K. C. Wong Education Foundation.
