Rational Design of Spherical Carbon Materials: Resolving Performance Trade-Offs in Electrochemical Energy Storage

The advancement of electrochemical energy storage is fundamentally constrained by the scarcity of electrode materials capable of synergistically combining high energy density, superior power density, and long-term cyclability. Spherical carbon materials offer an optimal platform for this purpose, providing a distinctive combination of high packing density, isotropic electron/ion transport, and structurally tunable hierarchical porosity. However, the field remains limited to fragmented and case-specific studies, lacking a universal framework to decipher intricate "structure-property" relationships and overcome fundamental performance trade-offs. To this end, this review proposes a pioneering "precursor, synthesis, structure, performance, and application" paradigm for comprehensively analyzing spherical carbon materials. This review methodically explores how precursor engineering and synthesis strategies dictate critical structural parameters and elucidates the mechanistic links between these architectures and their resulting electrochemical performance. Furthermore, we critically examine key strategies-such as hierarchical pore engineering, multiscale synergistic design, and interlayer/spatial modulation-that are instrumental in mitigating performance trade-offs. These strategies are examined across a range of applications, including metal-ion batteries, supercapacitors, Li-S batteries, and fuel cells. Finally, the review delineates prospective research trajectories, emphasizing challenges in sustainable synthesis, advanced mechanistic understanding, and practical device integration. This framework is designed to accelerate the rational design and realization of next-generation spherical carbon materials.