High-Energy Aqueous S-MnO₂ Batteries with Redox Charge Carriers

Area of Science:

• Electrochemistry
• Materials Science
• Energy Storage

Background:

• Conventional aqueous batteries suffer from low energy density due to limited electrode material capacities.
• Developing novel aqueous battery designs is crucial for advancing energy storage solutions.

Purpose of the Study:

• To design and construct innovative aqueous S-MnO2 batteries.
• To address the limitations of conventional aqueous battery electrode materials.

Main Methods:

• Constructed aqueous S-MnO2 batteries by coupling S/Cu2S redox couples with MnO2 deposition/dissolution.
• Utilized an acidic electrolyte compatible with both S/Cu2S conversion and MnO2 reactions.
• Assembled Ah-level prismatic and single-flow battery configurations.

Main Results:

• S/Cu2S redox couples exhibited a high specific capacity of 2220 mAh g-1 via a four-electron transfer solid-solid conversion reaction.
• Stable operation of S/Cu2S conversion was achieved in the acidic electrolyte.
• The batteries demonstrated a membrane-free configuration and stable operation for over 1000 hours.

Conclusions:

• The developed aqueous S-MnO2 batteries offer a promising alternative for large-scale energy storage.
• This work expands the scope of aqueous battery chemistry beyond traditional metal-manganese systems.