Breaking the Temperature Limit of Lithium‐Ion Batteries With Carbon Nanotube‐Based Electrodes and “Constructive Alliance” Electrolyte Strategy

Abstract

AbstractLithium‐ion batteries (LIBs) are paramount in energy storage in consumer electronics and electric vehicles. However, a narrow operating temperature range severely constrains their evolution. In this study, a wide‐temperature operating LIB system is constructed utilizing carbon nanotube (CNT)‐based electrodes and a “constructive alliance” electrolyte. The unique microstructure of the CNT current collector, with high electrical and thermal conductivity, accelerates the reaction kinetics of active materials at subzero temperatures and optimizes the thermal management of the entire electrode at elevated temperatures. Furthermore, a strategy employing the “constructive alliance” electrolyte is proposed, demonstrating that a simple combination of commercially available electrolytes can enhance resilience to harsh thermal conditions. Molecular dynamics simulations and density functional theory calculations reveal that the hybrid electrolyte predominantly adopts aggregate solvation structures and possesses low Li+ desolvation barriers regardless of thermal variations. Consequently, the assembled Li4Ti5O12//LiCoO2 full cell, with a negative/positive electrode material ratio of 1.2, exhibits outstanding electrochemical performance in the wide temperature range of −40 and 60 °C. This innovative strategy overcomes challenges in wide‐temperature electrolyte research and offers promise for next‐generation wide‐temperature LIBs.