Lithium-ion batteries (LIBs) are excellent electrochemical energy sources, albeit with existing challenges, including high costs and safety concerns. Magnesium-ion batteries (MIBs) are one of the potential alternatives. However, the performance of MIBs is poor due to their sluggish solid-state Mg²⁺ diffusion kinetics and severe electrode polarizability. Rechargeable magnesium-ion/lithium-ion (Mg²⁺/Li⁺) hybrid batteries (MLHBs) with Mg²⁺ and Li⁺ as the charge carriers create a synergy between LIBs and MIBs with significantly improved charge transport kinetics and reliable safety features. However, MLHBs are yet to reach a reasonable electrochemical performance as expected. This work reports a composite electrode material with highly defective two-dimensional (2D) tin sulphide nanosheets (SnS_x) encapsulated in three-dimensional (3D) holey graphene foams (HGF) (SnS_x/HGF), which exhibits a specific capacity as high as 600 mAh g⁻¹ at 50 mA g⁻¹ and a compelling specific energy density of ~ 330 Wh kg⁻¹. The excellent electrochemical performance surpasses previously reported hybrid battery systems based on intercalation-type cathode materials under comparable conditions. The role played by the defects in the SnS_x/HGF composite is studied to understand the origin of the observed excellent electrochemical performance. It is found that it is closely related to the defect structure in SnS_x, which offers percolation pathways for efficient ion transport and increased internal surface area assessable to the charge carriers. The defective sites also absorb structural stress caused by Mg²⁺ and Li⁺ insertion. This work is an important step towards realizing high-capacity cathode materials with fast charge transport kinetics for hybrid batteries.

锂离子电池 (LIB) 是极好的电化学能源，尽管存在成本高和安全问题等挑战。镁离子电池 (MIB) 是潜在的替代品之一。然而，由于其缓慢的固态Mg ²⁺扩散动力学和严重的电极极化率，MIBs 的性能较差。^{含 Mg 2+}和 Li ⁺的可充电镁离子/锂离子 (Mg ²⁺ /Li ⁺ ) 混合电池 (MLHB)因为电荷载体在 LIB 和 MIB 之间产生协同作用，具有显着改善的电荷传输动力学和可靠的安全特性。然而，MLHBs 尚未达到预期的合理电化学性能。这项工作报告了一种复合电极材料，其具有高度缺陷的二维 (2D) 硫化锡纳米片 (SnS _x )，封装在三维 (3D) 多孔石墨烯泡沫 (HGF) (SnS _x /HGF) 中，其表现出的比容量为在 50 mA g ^-1时高达 600 mAh g ^-1并且令人信服的比能量密度约为 330 Wh kg ^-1. 在可比较的条件下，优异的电化学性能超过了之前报道的基于插层型正极材料的混合电池系统。_{研究了 SnS x} /HGF 复合材料中缺陷所起的作用，以了解所观察到的优异电化学性能的起源。发现它与 SnS _{x中的缺陷结构密切相关，}它为有效的离子传输提供渗流途径，并增加电荷载流子可评估的内表面积。缺陷部位还吸收由 Mg ²⁺和 Li ^{+引起的结构应力}插入。这项工作是实现混合电池具有快速电荷传输动力学的高容量阴极材料的重要一步。