All-climate all-solid-state batteries enabled by high-entropy amorphous oxyhalide solid electrolytes

Abstract

Conventional lithium-ion batteries (LIBs) based on organic liquid electrolytes are limited to an operation temperature range of approximately −20 to +50 °C, mainly due to electrolyte decomposition and associated safety hazards, such as thermal runaway. All-solid-state batteries (ASSBs) provide inherent safety benefits but remain constrained by the limited temperature adaptability of solid electrolytes (SEs). Here, we address this challenge through a high-entropy design strategy, developing a high-entropy amorphous oxyhalide SE (Li_1.6Ta(PSiB)_0.15O_1.65Cl₅Br_0.1) that incorporates three synergistic features: (1) high-entropy multication mixing (Ta⁵⁺/P⁵⁺/Si⁴⁺/B³⁺) creating efficient ion-conduction pathways, (2) mixed-anion engineering (O²⁻/Cl⁻/Br⁻) lowering ionic migration barriers, and (3) the incorporation of non-metallic cations (P⁵⁺/Si⁴⁺/B³⁺) improving reduction stability, all within an amorphous framework that suppresses interfacial degradation. The optimized electrolyte exhibits an exceptional ionic conductivity of 7.1 mS cm⁻¹ at 25 °C alongside enhanced electrochemical stability. ASSBs fabricated with this high-entropy SE, a single-crystalline LiNi_0.8Co_0.1Mn_0.1O₂ (scNCM811) cathode, and a Li–In anode demonstrate outstanding wide-temperature-range-operation performance. An 82% capacity retention is achieved after 2400 cycles at 2C and 25 °C, with an ultra-low fading rate of 0.007 mAh per g per cycle. Zero capacity fade over 100 cycles at −30 °C and 80% capacity retention following 1300 cycles under 10C fast charging at 60 °C are demonstrated.