The severe swelling behavior of silicon-based electrodes caused by the large volume expansion of Si associated with Li still prevents the practical implementation of Si. Here, we report the amorphous carbon coated silicon/graphite granule (C@SGG) as an attractive anode material to control the swelling behavior and achieve improved electrochemical properties. With the structural uniqueness including inner buffer space, large contact area of silicon and graphite, and the uniform surface carbon coating layer, the C@SGG electrode exhibits stable cycling performance and regulated electrode swelling behavior. C@SGG shows high reversible capacity of 1150 mA h g⁻¹ and improved initial Coulombic efficiency of 85%. We evaluate C@SGG from a practical point of view through the characterization of pouch full cells prepared with LiCoO₂ as a cathode with a high areal capacity of 3.4 mA h cm⁻². The electrode prepared with the C@SGG of 10% and graphite of 90% (C@SGG 10% electrode) exhibits a stable cycling performance with a capacity retention of 71% over 500 cycles at 1 C-rate. Furthermore, the C@SGG 10% electrode exhibits stable electrode swelling behaviors comparable to the graphite electrode, indicating an initial expansion of 16.0% at a charged state and a cycling expansion of 6.7% over 50 cycles.

由于与Li相关的Si的大量体积膨胀而导致的硅基电极的严重溶胀行为仍然阻碍了Si的实际应用。在这里，我们报道了无定形碳包覆的硅/石墨颗粒（C @ SGG）作为有吸引力的阳极材料，以控制溶胀行为并实现改善的电化学性能。C @ SGG电极具有独特的结构独特性，包括内部缓冲空间，大的硅和石墨接触面积以及均匀的表面碳涂层，具有稳定的循环性能和可调节的电极溶胀行为。C @ SGG显示1150 mA hg ^-1的高可逆容量并将初始库仑效率提高了85％。我们从实用的角度，通过表征以LiCoO ₂为阴极制备的袋装满电池的特性来评估C @ SGG，其具有3.4 mA h cm ^-2的高面积容量。用10％的C @ SGG和90％的石墨制备的电极（C @ SGG 10％电极）表现出稳定的循环性能，在1 C速率下经过500次循环后的容量保持率为71％。此外，C @ SGG 10％电极表现出与石墨电极相当的稳定电极溶胀行为，表明在充电状态下的初始膨胀为16.0％，在50个循环中的循环膨胀为6.7％。