Fast‐Charging Halide‐Based All‐Solid‐State Batteries by Manipulation of Current Collector Interface

Abstract Poor rate capability is a significant obstacle for the practical application of inorganic all‐solid‐state lithium‐ion batteries (ASSLIBs). The charge transfer kinetics at the interface of current collectors is crucial for high‐rate capacity, but is typically neglected. In this paper, the interfacial evolution between Al foil current collectors and composite cathodes is studied in the LiCoO₂/Li₃InCl₆ (LCO/LIC) ASSLIBs at both 25 and −10 °C. The results indicate that the side reactions between Al foil and LIC are the main challenges for the interfacial stability of current collector at 25 °C. The design of a graphene‐like carbon (GLC) coating for the modification of Al avoids side reactions at the interface of current collector, resulting in improved cycling stability and high‐rate capacity. GLC Al ASSLIB exhibits a high initial capacity of 102.9 mAh g^–1 with a capacity retention of 89.1% after 150 cycles at 1 C. A high‐rate capacity of 69 mAh g^–1 is also achieved at 5 C. At −10 °C, the low Li⁺/electron transfer kinetics along with side reactions is the key limitation for the rate capability. Thanks to the GLC coating, the improved electrochemical performance is achieved with the enhanced charge transfer kinetics at the interface of current collector.