A Data-driven Framework to Accelerate the Discovery of Hybrid Cathode Materials for Metal-based Batteries

Abstract

Selecting materials for hybrid cathodes (HCs) for batteries, which involve a combination of intercalation and conversion materials, has gained interest due to their synergistic and averaged properties, enabling enhanced energy density and stability. Herein, we present a data-driven, chemistry-agnostic inverse material design framework for discovering HCs for metal-based batteries. This framework systematically explores the potential materials space for any given working ion, evaluates the candidate’s stability, and identifies the growth modes/adsorption of the components to identify stable HCs. To demonstrate the application of the framework, we performed a case study to discover HCs with an average gravimetric energy density surpassing that of the widely used high energy density NMC333 cathode material. The framework identified LiCr₄GaS₈-Li₂S as a promising HC with an average energy density of 1,424 Wh/kg (on a lithiated cathode basis) that exceeds NMC333’s maximum theoretical energy density of 1,028 Wh/kg. The identified HC has several additional desirable features: 1) its lithiated and delithiated phases are thermodynamically stable; 2) it undergoes minimal volumetric change upon (de)lithiation that mitigates the high-volumetric change of the conversion material; 3) it has a high energy density that ameliorates the low energy density of the intercalation material; 4) its intercalation component serves as both a conductive additive and support for sulfur species, immobilizing S while simultaneously contributing to the total cathode energy density; and finally, 5) It is expected to enhance durability and capacity retention over conventional Li-S batteries.