A high-performance aqueous zinc-ion battery with an extremely long cycle life in a weak magnetic field has been developed by a team led by Prof. Zhao Bangchuan at the Hefei Institutes of Physical Science of the Chinese Academy of Sciences (CAS). Materials Horizons published their findings.
A safer and less expensive alternative to lithium-ion batteries with a high theoretical capacity is zinc-ion batteries in water. However, the energy density and cycle life of aqueous zinc-ion batteries are impacted by zinc dendrite growth on the anode and the limited electrochemical performance of the cathode material. It is essential to design cathodes with a high energy density and prevent the growth of zinc dendrites in order to produce superior aqueous zinc-ion batteries.
The issue of zinc dendrite growth and the limitations imposed by existing cathode materials were overcome in this study. A VS2 material was produced through a one-step hydrothermal process combined with in-situ electrochemical defect engineering. The material had numerous flaws that significantly diminished the electrostatic interaction between vanadium disulfide (VS2) and zinc (Zn) ions. Zn2+ could be transported in three dimensions along the c- and ab-planes, resulting in excellent rate capability.
The dendrite growth remained a problem for cycling stability, but the researchers discovered that introducing an external magnetic field slowed the growth and significantly extended battery life. The high-performance Zn-VS2 battery demonstrated an extremely long cycle life and a high energy and power density when used in a weak magnetic field.
The team says that this work could have big effects on how energy storage technology will change in the future.
More information: Yunjie Mao et al, Magneto-electrochemistry driven ultralong-life Zn-VS2 aqueous zinc-ion batteries, Materials Horizons (2023). DOI: 10.1039/D3MH00303E
