Graphene-based tin dioxide (SnO₂) composite electrode is emerging as an attractive anode candidate for high-performance flexible lithium-ion batteries due to its excellent electronic conductivity, high theoretical capacity, and mechanical durability. However, the understanding of the underlying mechanism that how graphene contributes to the mechanical integrity and good electrochemical performances of flexible SnO₂ composite electrodes remains superficial. To this end, mechanical simulations aiming at directing the electrode structural design are highly desired. In this work, we reported a first-of-its-kind mechanical simulation on lithium intercalation induced stress in pristine SnO₂ anode and surface-modified SnO₂ composite anodes “wearing” soft (graphene)/hard (amorphous carbon) jacket. The simulation results quantitatively revealed that the double coatings are far more effective in reducing the charging-induced stresses and avoiding mechanical failure than pristine SnO₂ and amorphous carbon single protection. Based on this, a unique soft-and-hard double-jacketed flexible SnO₂ composite electrode with core-shelled C@SnO₂ embedded in graphene nanosheets was fabricated. In line with the mechanical simulations, the confinement of graphene encapsulation suppresses the crack formation, enhancing the mechanical integrity and the cyclic stability of the composite SnO₂ anodes. As expected, the obtained flexible anode shows high specific capacity (836 mAh•g⁻¹ at 100 mAg⁻¹), excellent rate capability (506 mAh•g⁻¹ at 2 Ag⁻¹) and ultra-stable cycling stability.

石墨烯基二氧化锡（SnO ₂）复合电极由于其优异的电子导电性，高理论容量和机械耐久性而成为高性能柔性锂离子电池的有吸引力的阳极候选材料。然而，对于石墨烯如何有助于柔性SnO ₂复合电极的机械完整性和良好的电化学性能的基本机理的理解仍然是肤浅的。为此，非常需要旨在指导电极结构设计的机械仿真。在这项工作中，我们报道了原始的SnO ₂阳极和表面改性的SnO _2中锂嵌入引起的应力的同类力学模拟。复合阳极“穿着”软（石墨烯）/硬（无定形碳）外套。仿真结果定量地表明，与原始SnO ₂和无定形碳单保护相比，双涂层在减少带电应力和避免机械故障方面更为有效。在此基础上，制备了一种独特的软硬双夹套柔性SnO ₂复合电极，其芯壳C @ SnO ₂嵌入石墨烯纳米片中。根据力学模拟，石墨烯封装的限制抑制了裂纹的形成，增强了复合材料SnO ₂的机械完整性和循环稳定性阳极。正如预期的那样，所得的软质阳极显示高比容量（836毫安时•克^-1在100 MAG ^-1），优良的速率能力（506毫安时•克^-1在2的Ag ^-1）和超稳定的循环稳定性。