Ultrahigh Areal Capacity Hydrogen‐Ion Batteries with MoO<sub>3</sub> Loading Over 90 mg cm<sup>−2</sup>
Zhen Su, Wenhao Ren, Haocheng Guo, Xuancheng Peng, Xianjue Chen, Chuan Zhao
Abstract
Abstract High areal capacity electrodes are essential to practical energy storage devices to achieve high volumetric capacity with compacted size. However, high loading of active materials remains a fundamental challenge for most metal‐ion batteries (e.g., Li + , Na + , K + ) due to sluggish mass transfer kinetics and poor processability. Here, an ultrahigh areal capacity MoO 3 electrode based on high loading for hydrogen‐ion battery is shown. Hydrogen ions can rapidly intercalate/deintercalate into/from MoO 3 ‐nanofibers anode with a high specific capacity of 235 mAh g −1 at 5 C and superior rate capability up to 200 C at a low loading (≈1 mg cm −2 ). Attributed to the ultrafast H + diffusion in thick MoO 3 electrode, an areal capacity of 22.4 mAh cm −2 is achieved at the loading over 90.48 mg cm −2 , which is the highest areal capacity ever reported for electrodes of rechargeable batteries, to the best of the authors’ knowledge. This study paves the way toward high areal capacity batteries with high‐loading active materials.