Jan 12 2021
Lithium-ion batteries play a crucial role in modern life, right from powering cell phones and laptops to the new holiday toys. However, there is a safety threat—the batteries can catch fire.
Xiaonan Shan, assistant professor of electrical and computer engineering, said the discovery offers promise for energy storage and other applications, including electric vehicles. Image Credit: University of Houston.
Zinc-based aqueous batteries prevent the threat of fire by making use of a water-based electrolyte rather than the traditional chemical solvent. But unchecked growth of dendrite restricts their potential to offer the long life and high performance required for practical applications.
Currently, scientists have described in the Nature Communications journal that a new 3D zinc-manganese nano-alloy anode has solved these drawbacks, leading to a steady, high-performance, dendrite-free aqueous battery that uses seawater as the electrolyte.
According to Xiaonan Shan, the co-corresponding author of the study and an assistant professor of electrical and computer engineering at the University of Houston (UH), the breakthrough provides promise for energy storage and other applications, like electric vehicles.
It provides a low-cost, high energy density, stable battery. It should be of use for reliable, rechargeable batteries.
Xiaonan Shan, Study Co-Corresponding Author and Assistant Professor of Electrical and Computer Engineering, University of Houston
In addition, Shan and UH PhD student Guangxia Feng have designed an in situ optical visualization method, which enables them to instantly observe the reaction dynamics on the anode in real time.
This platform provides us with the capability to directly image the electrode reaction dynamics in situ. This important information provides direct evidence and visualization of the reaction kinetics and helps us to understand phenomena that could not be easily accessed previously.
Xiaonan Shan, Study Co-Corresponding Author and Assistant Professor of Electrical and Computer Engineering, University of Houston
Testing revealed that the latest 3D zinc-manganese nano alloy anode continued to be stable without degrading over 1,000 hours of charge or discharge cycling under high current density (80 mA/cm2).
The anode is the electrode that discharges current from a battery, while electrolytes act as the medium through which the ionic charge flows between the anode and the cathode. The use of seawater as the electrolyte instead of highly purified water provides paves another way for decreasing battery charges.
In aqueous batteries that use traditional anode materials, the anode is prone to dendrites—tiny growths that can cause the battery to lose power. Shan and his collaborators have proposed and illustrated an approach to efficiently reduce and inhibit the development of dendrite in aqueous systems by regulating surface reaction thermodynamics with a zinc alloy and reaction kinetics with the help of a three-dimensional structure.
According to Shan, scientists at UH and the University of Central Florida are now examining other metal alloys, besides the zinc-manganese alloy.
Apart from Shan and Feng, scientists involved in the study include Huajun Tian, Zhao Li, David Fox, Lei Zhai, Akihiro Kushima, and co-corresponding author Yang Yang, all from the University of Central Florida; Zhenzhong Yang and Yingge Du, both from Pacific Northwest National Laboratory; Maoyu Wang and co-corresponding author Zhenxing Feng, both from Oregon State University; and Hua Zhou from Argonne National Laboratory.
Journal Reference
Tian, H., et al. (2021) Stable, high-performance, dendrite-free, seawater-based aqueous batteries. Nature Communications. doi.org/10.1038/s41467-020-20334-6.
Source: https://www.uh.edu/