Large‐Scale Fabrication of Stable Silicon Anode in Air for Sulfide Solid State Batteries via Ionic‐Electronic Dual Conductive Binder

Abstract

AbstractThe construction of a continuous ionic/electronic pathway is critical for Si‐based sulfide all‐solid‐state batteries (ASSBs) with the advantages of high‐energy density and high‐cycle stability. However, a significant impediment arises from the parasitic reaction occurring between the ionic sulfide solid‐state electrolyte and electronic carbon additive, posing a formidable challenge. Additionally, the fabrication of electrodes necessitates stringent operational conditions, further limiting practical applicability. Herein, an ionic–electronic dual conductive binder for the fabrication of robust silicon anode under ambient air conditions in the absence of high‐cost and air‐sensitive sulfide solid‐state electrolyte for ASSBs is reported. This binder incorporates in situ reduced silver nanoparticles into a high‐strength polymer rich in ether bonds, establishing a conductive pathway for lithium ions and electrons. With the binder‐composited Si anode, the half‐cell exhibits a remarkable capacity of 1906.9 mAh g−1 and stable cycling for 500 cycles at a current density of 2 C (4.4 mA cm−2) under a low stack pressure of 5 MPa. The full cell using Ni0.9Co0.075Mn0.025O2 (NCM90) exhibits a remark cycling stability within 2000 cycles at 5 C (8 mA cm−2). This work presents an inspired design of functional binders for large‐scale manufacture and mild operation in a low‐cost way for Si anodes in ASSBs.