Concentrated Electrolytes Enabling Stable Aqueous Ammonium-Ion Batteries.

Area of Science:

• Electrochemistry
• Materials Science
• Energy Storage

Background:

• Rechargeable aqueous batteries offer safe, eco-friendly, and cost-effective energy storage solutions.
• Aqueous ammonium-ion batteries (AAIB) show promise due to rapid ammonium-ion diffusion, but electrode stability remains a challenge.
• Developing stable electrodes is crucial for achieving high-performance AAIBs with significant output potential.

Purpose of the Study:

• To develop and characterize a stable aqueous ammonium-ion battery (AAIB) with high performance.
• To investigate the electrode-electrolyte interface and interphase properties of the AAIB system.
• To evaluate the long-term cycling stability and output potential of the novel AAIB.

Main Methods:

• Fabrication of an AAIB using a concentrated aqueous ammonium sulfate electrolyte, ammonium copper hexacyanoferrate (N-CuHCF) cathode, and 3,4,9,10-perylene-bis(dicarboximide) (PTCDI) anode.
• Systematic investigation using a combination of theoretical and experimental methods.
• Analysis of solvation structure, electrochemical properties, and electrode-electrolyte interface.

Main Results:

• The developed AAIB exhibits remarkable cycling performance with approximately 72% capacity retention after 1000 cycles.
• The battery achieves an average output potential of approximately 1.0 V.
• The study provides insights into the electrode-electrolyte interactions within the AAIB system.

Conclusions:

• A stable and high-performance aqueous ammonium-ion battery (AAIB) has been successfully developed.
• The N-CuHCF and PTCDI electrode combination in a concentrated aqueous electrolyte offers a promising low-cost energy storage solution.
• The findings contribute to the advancement of safe and efficient large-scale energy storage technologies.