Rational design of highly conductive and stable 3D flexible composite current collector for high performance lithium-ion battery electrodes

Anode active materials involving transition metal oxides and sulfides are of great significance for high energy density lithium-ion batteries (LIBs), but the huge volume expansion and inferior electronic conductivity upon cycling critically constrain their further application. Herein, from a new perspective, a highly conductive and stable 3D flexible composite current collector is rationally designed by facilely electrodepositing metallic Ni thin layer onto the carbon cloth (CC/Ni), which endows the supported active materials with exceptional electronic conductivity and structural stability. In addition, the homogeneously distributed metallic Ni protrusions external CC can strongly bond with the active components, ensuring the structural integrity of electrodes upon cycling. More importantly, the 3D network structure with large specific surface area provides abundant space to alleviate the volume expansion and more active sites for electrochemical reactions. Therefore, taking Ni3S2 nanosheet (Ni3S2 NS) anode as an example, the prepared Ni3S2 NS@CC/Ni electrode shows a high specific capacity of 2.32 mAh/cm2 at 1 mA/cm2 and high capacity retention of 1.68 mAh/cm2 at a high rate of 8 mA/cm2. This study provides a universal approach to obtain highly conductive and stable 3D flexible current collectors towards high performance metal-ion batteries beyond LIBs. A highly conductive and stable 3D flexible composite current collector is rationally designed by facilely electrodepositing metallic Ni thin layer onto the carbon cloth (CC/Ni), which endows the electrode with exceptional cycling and rate performance [Display omitted]