Regulation of an Inner Helmholtz Plane by hierarchical porous biomass activated carbon for stable cathode electrolyte interphase films

Abstract

Abstract The formation of a cathode electrolyte interphase (CEI) layer and the transportation of ions at the electrode/electrolyte interface in batteries rely on the structure of the charge distribution in the Inner Helmholtz Plane (IHP) in the electrical double layer. Herein, a novel hierarchical porous activated carbon (AC) additive with a powerful electrical double layer capacity that is used in cathodes for lithium-ion batteries (LIBs) is developed using low-cost and abundant persimmon branches as the raw material. The AC additives strengthen the IHP on the cathode surface and induce the formation of Li2CO3, which is one of the main components in the CEI layer on the surface of cathode materials. Moreover, after AC was used as an additive in the cathode, the discharge capacity increased from 49 mAh g−1 to 92 mAh g−1. Cycling tests reveal that the additive reduces the capacity loss after extended cycling at a high current density.