Hierarchical graphite foil/CoNi2S4 flexible electrode with superior thermal conductivity for high-performance supercapacitors

Effective heat dissipation is a crucial issue in electrochemical energy storage devices. Thus, it is highly desirable to develop high-performance electrode materials with high thermal conductivity. Here, we report a facile one-step electrodeposition method to synthesize ternary cobalt nickel sulfide（CoNiS）flower-like nanosheets which are grown on graphite foil（GF） as binder-free electrode materials for supercapacitors. The as-fabricated GF/CoNiSintegrated electrode manifested an excellent thermal conductivity of 620.1 W·m·Kand a high specific capacitance of 881 F·gat 5 mA cm, as well as good rate capability and cycling stability. Ultimately, the all-solid-state symmetric supercapacitor based on these advanced electrodes demonstrated superior heat dissipation performance during the galvanostatic charge-discharge processes. This novel strategy provides a new example of effective thermal management for potential applications in energy storage devices.