Resorcinol/formaldehyde resin-derived carbon conductive network for superior fluorinated graphite based lithium primary batteries

The high energy density of fluorinated graphite (CFx) based lithium primary battery has aroused tremendous attention. However, the nonconductive CFx always induces high interface impedance and low power density. Herein, the carbon conductive network is generated by thermal treatment of resorcinol/formaldehyde (RF) resin on CFx and RF resin spheres (RF RSs), a conductive carbon layer coats on CFx surface, the electrical conductivity of CFx is improved. The oxygen functional groups in incomplete carbonized RF RSs also dedicate to the electrochemical performance of CFx. When different mass ratios of CFx/RF RSs are employed, the cathodes exhibit improved rate performance and voltage plateaus, and the initial voltage delays observed in CFx are significantly reduced. Notably, CFx/RF RSs−13 cathode delivers an impressive discharge capacity of 843.8 mAh g−1 with a voltage plateau of 2.68 V at 10 mA g−1. This leads to the maximum energy density of 2174.9 Wh kg−1 and a peak power density of 18600 W kg−1. Additionally, CFx/RF RSs−13 cathode demonstrates commendable electrochemical stability across a wide temperature spectrum (−20–70 °C). Given these superior electrochemical attributes, the CFx/RF RSs combination holds significant promise for deployment in high-power devices and for standard operations under extreme temperature conditions.