Thermoelectric Functionalization of Key Materials in Lithium‐Ion Batteries: From External Thermal Management to Internal Heat Protection

ABSTRACT Lithium‐ion batteries (LIBs) demand precise thermal management to ensure safety and longevity, as operation outside the ideal temperature window accelerates degradation and increases the risk of thermal runaway. Thermoelectric cooling based on the Peltier effect exhibits significant advantages due to its solid‐state design, rapid response, and precise bidirectional temperature control. This review systematically summarizes the latest advances in thermoelectric functionalization for LIBs, including temperature monitoring via thermocouples and external thermal management using thermoelectric coolers, from standalone modules to advanced hybrid architectures. Furthermore, it explores the emerging direction of intrinsic thermoelectric functionalization of key materials, representing a shift toward internal heat protection and self‐regulating thermal management. This review also thoroughly discusses the critical barriers limiting the transition from laboratory to commercial application and provides a perspective on realizing intrinsically safe energy storage systems via thermoelectrics.