Low-Cost H2/Na0.44MnO2 Gas Battery for Large-Scale Energy Storage

Hydrogen gas secondary cells are generating significant interest as a prospective solution for emerging electrical energy storage, owing to their high rechargeability and stability. However, their application is generally hindered by the high cost associated with Ni-based cathodes or Pt-based anodic catalysts. Here, we propose a low-cost alkaline H2/Na0.44MnO2 gas battery, which involves a Na0.44MnO2 cathode and an H2 gas anode in an alkaline electrolyte (6 M NaOH). The operation of the alkaline H2/Na0.44MnO2 gas battery depends on Na+ insertion/extraction in the Na0.44MnO2 cathode and H+/H2 conversion in the anode with a NiMoCo-based catalyst. Additionally, within a voltage range of 0.6–1.5 V, the alkaline H2/Na0.44MnO2 gas battery showcases a significant reversible capacity (95.2 mA h g–1 at 0.2 C) and an exceptional stability (capacity retention of 81.9% over 500 cycles at 1 C). With its cost effectiveness, environmental friendliness, and high level of safety, the alkaline H2/Na0.44MnO2 battery emerges as an appealing choice for scalable energy storage.