Design and development of single crystal cobalt-free cathodes for lithium-ion batteries

초록

The development of high energy density and sustainable lithium-ion batteries (LIBs) has accelerated interest in cobalt (Co)-free cathode materials due to concerns over cost, environmental impact, and supply risks. Among these, single-crystal (SC) Co-free cathodes have emerged as promising candidates owing to their superior structural integrity, enhanced thermal stability, and improved cycling durability compared with polycrystalline counterparts. This review summarizes recent progress across four major material systems: Ni-rich layered oxides, Li–Mn-rich layered compounds, spinel-type oxides, and olivine-based materials. Key advances in synthesis methods, including molten-salt, hydrothermal, and co-precipitation approaches, are discussed in relation to achieving phase-pure SC architectures with reduced defects. In addition, effective modification strategies such as heteroatom doping, surface engineering, and facet regulation are highlighted for their roles in improving Li+ transport, interfacial stability, and electrochemical performance. Despite these advances, critical challenges remain, including sluggish anisotropic Li+ diffusion, oxygen instability at high voltages, and scalability for practical applications. Future efforts focusing on advanced interface design, entropy engineering, and scalable synthesis are expected to further enhance the performance of SC Co-free cathodes. This review provides insights into rational design strategies for next-generation high performance LIBs. © 2026 Elsevier Ltd. All rights are reserved, including those for text and data mining, AI training, and similar technologies.

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