A Stable Cross‐Linked Binder Network for SnO2 Anode with Enhanced Sodium‐Ion Storage Performance

Abstract Stable binder network of anode is essential for the enhanced cycling performance of lithium ion battery electrode especially for SnO 2 anode, which has a big volume expansion/shrink during cycling. Here, we designed a cross‐linked polymer adhesive networks for SnO 2 anode of sodium‐ion battery by utilizing esterification reaction of PAA (Polyacrylic acid) and SS (soluble starch). The cross‐linked adhesive networks can effectively enhance the contact between conductive agent and SnO 2 particles, meanwhile serve as a buffer matrix of the expansion of SnO 2 during cycling and a protecting layer to reduce the contact of SnO 2 anode and electrolyte. As a result, a stable specific capacity of 370 mA h g −1 of the PAA‐SS@SnO 2 anode was obtained at a current density of 0.1 A g −1 after 150 cycles, while the specific capacity of PVDF@SnO 2 anode is only 200 mA h g −1 after 50 cycles. This cross‐linked adhesive networks present an effective and universal approach for application of pure SnO 2 as high performance anode of sodium ion batteries.