Mass Loading‐Independent Lithium Storage of Transitional Metal Compounds Achieved by Multi‐Dimensional Synergistic Nanoarchitecture

Abstract Nanostructured transitional metal compounds (TMCs) have demonstrated extraordinary promise for high‐efficient and rapid lithium storage. However, good performance is usually limited to electrodes with low mass loading (≤1.0 mg cm −2 ) and is difficult to realize at higher mass loading due to increased electrons/ions transport limitations in the thicker electrode. Herein, the multi‐dimensional synergistic nanoarchitecture design of graphene‐wrapped MnO@carbon microcapsules (capsule‐like MnO@C‐G) is reported, which demonstrates impressive mass loading‐independent lithium storage properties. Highly porous MnO nanoclusters assembled by 0D nanocrystals facilitate sufficient electrolyte infiltration and shorten the solid‐state ions transport path. 1D carbon shell, 2D graphene, and 3D continuous network with tight interconnection accelerate electrons transport inside the thick electrode. The capsule‐like MnO@C‐G delivers ultrahigh gravimetric capacity retention of 91.0% as the mass loading increases 4.3 times, while the areal capacities increase linearly with the mass loading at various current densities. Specifically, the capsule‐like MnO@C electrode delivers a remarkable areal capacity of 2.0 mAh cm −2 at a mass loading of 3.0 mg cm −2 . Moreover, the capsule‐like MnO@C also demonstrates excellent performance in full battery applications. This study demonstrates the effectiveness of multi‐dimensional synergistic nanoarchitecture in achieving mass loading‐independent performance, which can be extended to other TMCs for electrochemical energy storage.