Aqueous ammonium-ion battery capacity boosted with electrode preparation

Green energy relies heavily on batteries, and lithium-ion batteries are currently the leading option given their high energy densities. However, lithium-ion batteries are not suitable for all situations due to their flammability risk. Aqueous ammonium-ion batteries, which have a non-flammable electrolyte, offer an economical and environmentally-friendly alternative. While these batteries can be safer and more durable, they currently have limited energy storage capacity.

To overcome this limitation, Lu et al. developed a method to improve the ammonium-ion storage capacity of vanadium pentoxide, a promising electrode material, through orbital electron tuning and crystal engineering.

The method uses a two-step process of hydrothermal synthesis followed by a post-anneal treatment that enhances the electrostatic force between the ammonium active sites and the vanadium center and allows for increased ammonium storage capacity. The electron configuration achieved through this process also increases the electrode capacity by improving electron transport.

“The capacity of as-prepared vanadium pentoxide electrode is superior to most of the previously reported anode materials, which is beneficial in designing next-generation high-energy ammonium-ion batteries,” said author Xihong Lu. “We hope that our study can offer a simple and efficient way to reach high-capacity electrodes and will provide a new strategy for preparing advanced aqueous ammonium-ion batteries.”

The authors believe their orbital electron modification technique could also work with thick metal oxide electrodes. They plan to continue working on improving the electrochemical performance to broaden potential applications of aqueous ammonium-ion batteries.

Source: “3D orbital electron tunning and crystal engineering enables high-capacity vanadium oxide for aqueous ammonium ion batteries,” by Tzu-Hao Lu, Qiyu Liu, Ang Yi, Hao Liu, Yanxia Yu, and Xihong Lu, APL Energy (2024). The article can be accessed at https://doi.org/10.1063/5.0221284 .