In the search for novel anode materials for lithium-ion batteries (LIBs), organic electrode materials have recently attracted substantial attention and seem to be the next preferred candidates for use as high-performance anode materials in rechargeable LIBs due to their low cost, high theoretical capacity, structural diversity, environmental friendliness, and facile synthesis. Up to now, the electrochemical properties of numerous organic compounds with different functional groups (carbonyl, azo, sulfur, imine, etc.) have been thoroughly explored as anode materials for LIBs, dividing organic anode materials into four main classes: organic carbonyl compounds, covalent organic frameworks (COFs), metal-organic frameworks (MOFs), and organic compounds with nitrogen-containing groups. In this review, an overview of the recent progress in organic anodes is provided. The electrochemical performances of different organic anode materials are compared, revealing the advantages and disadvantages of each class of organic materials in both research and commercial applications. Afterward, the practical applications of some organic anode materials in full cells of LIBs are provided. Finally, some techniques to address significant issues, such as poor electronic conductivity, low discharge voltage, and undesired dissolution of active organic anode material into typical organic electrolytes, are discussed. This paper will guide the study of more efficient organic compounds that can be employed as high-performance anode materials in LIBs.

Research on the regeneration of cathode materials of spent lithium-ion batteries for resource reclamation and environmental protection is attracting more and more attention today. However, the majority of studies on recycling lithium-ion batteries (LIBs) placed the emphasis only on recovering target metals, such as Co, Ni, and Li, from the cathode materials, or how to recycle spent LIBs by conventional means. Effective reclamation strategies (e.g., pyrometallurgical technologies, hydrometallurgy techniques, and biological strategies) have been used in research on recycling used LIBs. Nevertheless, none of the existing reviews of regenerating cathode materials from waste LIBs elucidated the strategies to regenerate lithium nickel manganese cobalt oxide (NCM or LiNi_xCo_yMn_zO₂) cathode materials directly from spent LIBs containing other than NCM cathodes but, at the same time, frequently used commercial cathode materials such as LiCoO₂ (LCO), LiFePO₄ (LFP), LiMn₂O₄ (LMO), etc. or from spent mixed cathode materials. This review showcases the strategies and techniques for regenerating LiNi_xCo_yMn_zO₂ cathode active materials directly from some commonly used and different types of mixed-cathode materials. The article summarizes the various technologies and processes of regenerating LiNi_xCo_yMn_zO₂ cathode active materials directly from some individual cathode materials and the mixed-cathode scraps of spent LIBs without their preliminary separation. In the meantime, the economic benefits and diverse synthetic routes of regenerating LiNi_xCo_yMn_zO₂ cathode materials reported in the literature are analyzed systematically. This minireview can lay guidance and a theoretical basis for restoring LiNi_xCo_yMn_zO₂ cathode materials.

While past recycling efforts have primarily concentrated on extracting valuable metals from discarded cathode materials, the focus is now shifting towards anode materials, particularly graphite, which makes up 10–20% of LIB mass. Escalating prices of battery-grade graphite and environmental considerations surrounding its production highlight the significance of graphite recycling. This review categorizes methods for graphite recovery into three approaches: recovery, recycle, and reuse. Moreover, it explores their potential applications and comparative electrochemical performance analysis, shedding light on the promising prospects of utilizing spent graphite-based functional materials. The review underscores the importance of sustainable recycling practices to address the environmental and economic challenges posed by the proliferation of LIBs and the growing demand for graphite.

In recent years, 3D printing has emerged as a promising technology in energy storage, particularly for the fabrication of Li-ion battery electrodes. This innovative manufacturing method offers significant material composition and electrode structure flexibility, enabling more complex and efficient designs. While traditional Li-ion battery fabrication methods are well-established, 3D printing opens up new possibilities for enhancing battery performance by allowing for tailored geometries, efficient material usage, and integrating multifunctional components. This article examines three key 3D printing methods for fabricating Li-ion battery electrodes: (1) material extrusion (ME), which encompasses two subcategories—fused deposition modeling (FDM), also referred to as fused filament fabrication (FFF), and direct ink writing (DIW); (2) material jetting (MJ), including inkjet printing (IJP) and aerosol jet printing (AJP) methods; and (3) vat photopolymerization (VAT-P), which includes the stereolithographic apparatus (SLA) subcategory. These methods have been applied in fabricating substrates, thin-film electrodes, and electrolytes for half-cell and full-cell Li-ion batteries. This discussion focuses on their strengths, limitations, and potential advancements for energy storage applications.