Honeycomb‐Inspired Surface‐Patterned Cu@CuO Composite Current Collector for Lithium‐Ion Batteries

Abstract

The interface design between the current collector and active materials has a non‐negligible effect on the performance of lithium‐ion batteries (LIBs). Inspired by the honeycomb with a large specific surface area, this work validates the use of a surface‐patterned cellular Cu@CuO composite current collector with a hexagonal blind hole array and a nanostructured film of CuO nanoflowers for LIBs. This unique structure is synthesized by lithography and solution immersion. Mesocarbon microbead graphite powders are used as the active materials. Results show that the battery with the cellular Cu@CuO current collector maintains a reversible charge capacity of 354.1 mAh g−1 at 100 mA g−1 after 200 cycles. Compared with the Cu‐based current collector with a hexagonal blind hole array and a bare Cu current collector, the new pattern gains a performance improvement in the reversible capacity by 27.9% and 153.2%, respectively. The excellent electrochemical property of the cellular Cu@CuO current collector can be ascribed to strengthened adhesion with the active materials, reduced contact resistance, and improved Li‐ion diffusion capability. Due to the enhanced electrochemical performance, facile preparation processes, and cost‐effective raw materials, the new current collector shows great potential to replace the conventional current collector of energy storage systems.