Nickel ion-anchored helical braided binder network with soft-rigid synergy and self-recovery ability for high-performance silicon anode

Silicon (Si) is one of the most promising anode materials for high-capacity lithium-ion batteries. However, its drastic volume changes during cycling lead to fast capacity decay. Binders play an important role in maintaining the structural integrity of electrodes. This paper proposes a three-dimensional binder network, which synthesized by weaving Ni 2+ anchored soft gellan gum chains with linear rigid polyvinyl alcohol chains. Benefiting from the soft-rigid synergy and self-recovery ability of the obtained binder, the Si anode delivers over 1500 mAh g −1 after 500 cycles at 2.1 A g −1 , and post-analysis proofs that this binder can buffer the volume changes of Si particles and retain the overall stability of the electrode. In addition, the optimized Si anode still have a high capacity retention of ca. 50% even at 84 A g −1 , because the binder network can provide uniform Li + flux and more Li + transport channels for the electrode.