Abstract: As a novel type of porous electrode material, covalent organic frameworks (COFs) possess significant advantages, including high structural diversity, controllable pore networks, and ease of chemical modification, making them one of the leading materials in the field of electrochemical energy storage (EES). However, most COFs suffer from poor electrical conductivity and severe aggregation, significantly hindering their practical application in energy storage. This article systematically summarized the current status, challenges, and modification strategies of COFs in energy storage research. Given the pronounced effectiveness and widespread applicability of exfoliation for modifying COF materials, this review particularly emphasized the exfoliation strategy, detailing the methods for obtaining few-layer or even monolayer covalent organic nanosheets (CONs). Among these methods, mechanical grinding and liquid-phase-assisted exfoliation were widely used due to their operational simplicity. Finally, the review addressed the challenges and improvement strategies encountered in applying COF materials to lithium-ion batteries (LIBs), with an emphasis on the importance of obtaining monolayer CONs via exfoliation, and their application prospects in the LIB field were also discussed.