Physicochemical Dual Crosslinking Conductive Polymeric Networks Combining High Strength and High Toughness Enable Stable Operation of Silicon Microparticles Anodes.

The poor interfacial stability and insufficient cycle performance caused by the undesirable stress hinder the commercial application of silicon microparticles (μSi), as next-generation anode materials for high-energy-density lithium-ion batteries. Herein, we design a conceptionally novel physicochemical dual crosslinking conductive polymeric network combining with high strength and high toughness by coupling stiffness of polyacrylic acid and softness of carboxyl nitrile rubber, which includes multiple H-bonds by introducing highly branched tannic acid, as physical cross-linker. Such a design enables effective stress dissipation by folded molecular chains slipping and sequential H-bonds cleavage, thus stabilize the electrode interface and enhance cycle stability. As expected, the resultant electrode (μSi/PTBR) delivers an unprecedented high capacity retention of ∼ 97% from 2027.9 mAh g -1 at 19 th to 1945.7 mAh g -1 at 200 th cycle at 2 A g -1 . Meanwhile, this unique stress dissipation strategy is also suitable for stablizing SiO x anodes with much low capacity loss of ∼ 0.012% per cycle over 1000 cycles at 1.5 A g -1 . Atomic force microscopy analysis and finite element simulations reveal the excellent stress distribution ability of physicochemical dual crosslinking conductive polymeric network. This work provides an efficient energy dissipation strategy towards practical high-capacity anodes for energy-dense batteries. This article is protected by copyright. All rights reserved.