Controllable and scalable prelithiation of dry silicon-based anodes for high-energy-density lithium-ion batteries

Abstract

High-energy-density batteries using high mass loaded silicon (Si)-based anode are of great interest to battery manufacturers as a transition toward next-generation storage technology. However, the huge volume expansion and insufficient cation utilization accompanied by low initial Coulombic efficiency of the anode limit the battery performance. Herein, a cost-effective and controllable clinging prelithiation strategy for high-loaded dry Si-based electrodes is proposed to achieve a homogeneous prelithiation process with improved structural stability and higher initial Coulombic efficiency. The sufficient interior space enabled by dry electrode technology and uniformly distributed lithiated alloy phases can tolerate large volume changes and avoid irreversible capacity loss, thereby improving Li utilization and enhancing cycle stability. With this prelithiation strategy, initial Coulombic efficiency (ICE) can be improved by 22.3%-25.1% to around 100% even under a high-loading Si-based anode of 16.51 mg cm^-2 with reduced open circuit voltage. Therefore, the assembled full cell paired with both electrodes fabricated via dry electrode technology further exhibits an improved ICE of 98.73% with high capacity retention of 88.15% over 300 cycles, suggesting that dry electrode technology combined with the prelithiation method is suitable for optimizing high Si loading anode for next-generation high energy density batteries.