Researchers have designed a dual-phase modification strategy for lithium fluorinated carbon batteries operating down to minus 70 degrees Celsius. The peer-reviewed findings were published in Nature Communications on Aug. 25, 2026.
Low-temperature Li||CFx batteries typically suffer severe degradation caused by the electrically insulating nature of CFx and sluggish lithium-ion kinetics. To resolve these bottlenecks, the research team used plasma-enhanced chemical vapor deposition to fabricate mesoporous CFx cathodes coated conformally with carbon. The researchers also used an electrolyte formulation that generates an in situ, sulfur-rich inorganic interphase layer directly on the cathode surface. The engineered porous framework provides open diffusion channels for lithium ions, while the carbon coating improves electrical conductivity and prevents lithium fluoride stacking.
Laboratory measurements showed the optimized Li||CFx system delivered a discharge capacity of 428.4 milliampere-hours per gram at minus 50 degrees Celsius under a current density of 2 amperes per gram. At minus 70 degrees Celsius and 0.1 amperes per gram, the system yielded 333.4 milliampere-hours per gram. Built into practical 5-ampere-hour pouch cells, the architecture delivered specific energies of 470 watt-hours per kilogram at minus 50 degrees Celsius and 332 watt-hours per kilogram at minus 70 degrees Celsius under a current density of 0.01 amperes per gram.
Scientists from Nankai University, Peking University, the Beijing Graphene Institute, and Guizhou Meiling Power Sources co-authored the project with financial support from the Natural Science Foundation of China and research funds in Tianjin. Co-authors Huan Wang and Wei Wang disclosed an associated Chinese patent application, number Z.L. 2024 1 1398561.1, covering the synthesis of positive electrode materials and electrolytes for wide-temperature Li||CFx cells.
