Carbon-based film-assisted low-temperature heating for LFP batteries: Evaluating short-term performance and long-term degradation

Low-temperature environments substantially degrade lithium-ion battery performance, underscoring the need for efficient heating strategies. Carbon-based heating films offer considerable potential for vehicular low-temperature thermal management due to their favorable material properties, yet research has largely centered on feasibility rather than on key influencing factors or heating-induced long-term degradation. This study systematically evaluates three critical factors governing the performance of carbon-film-based heating methods and compares the short- and long-term effects of four vehicle-representative heating configurations. In short-term tests, the double-sided external heating configuration achieves charging efficiency more than twice that of the unheated battery, while the double-sided composite self-heating configuration provides superior capacity enhancement of up to 77%. Long-term cycling results show that double-sided external heating induces minimal capacity fade, whereas single-sided composite self-heating produces more significant degradation and structural damage. Overall, the findings highlight the distinct advantages of each heating configuration under low-temperature conditions and emphasize the importance of aligning heating architecture with operational requirements for safe and efficient battery heating. This work establishes an integrated framework for selecting short- and long-term heating strategies across diverse low-temperature scenarios and provides a comprehensive evaluation of their performance and degradation pathways.