New design strategy boosts lithium alloy electrodes for solid-state batteries

by Clarence Oxford

Los Angeles CA (SPX) Nov 08, 2025

A team co-led by engineers at the University of California San Diego has introduced a new approach to designing metal alloy negative electrodes that may deliver important advances in solid-state battery technology for electric vehicles and other high-performance energy storage applications.

Focusing on lithium-aluminum alloy negative electrodes, the research group examined how lithium ions travel through distinct phases of the material – a lithium-rich beta phase and a lithium-poor alpha phase. By precisely adjusting the lithium-to-aluminum ratio, the researchers were able to greatly increase the share of the beta phase within their test materials.

The team found that a higher concentration of beta phase enhanced the transport of lithium ions, with diffusion rates in the beta phase up to ten billion times faster than those observed in the alpha phase. This resulted in electrode structures that were both denser and more stable, while creating more effective pathways for lithium movement between the electrode and the solid electrolyte.

Solid-state batteries assembled with beta phase-enriched lithium-aluminum alloy electrodes demonstrated high charging and discharge rates, retaining stable capacity across more than 2,000 charge cycles in laboratory tests. These results indicate the potential for longer battery lifespan and faster recharging in future battery-powered devices and vehicles.

This study marks the first time a direct relationship has been established between the distribution of the beta phase and lithium diffusion within lithium-aluminum alloys. According to the research group, the findings provide guidance for engineering next-generation alloy-based battery electrodes with higher energy density, faster charge performance, and improved reliability.

Research Report:Lithium diffusion-controlled Li-Al alloy negative electrode for all-solid-state battery