Scientists have made a significant breakthrough in creating safer, longer-lasting zinc batteries that could soon replace lithium-ion batteries.
A research team, led by Dr. Jung-Je Woo from the Korea Institute of Energy Research and Professor Jaephil Cho from Ulsan National Institute of Science and Technology, has developed a technology to solve one of the biggest problems in zinc batteries: the formation of “dendrites.”
Their findings were recently published in the journal Advanced Energy Materials.
Zinc batteries, which use water as the electrolyte, are safer and more environmentally friendly than lithium-ion batteries.
The reason is that lithium-ion batteries use flammable liquids, while zinc batteries do not have a fire risk.
Zinc batteries also have the potential to store more energy because they use two electrons per ion, while lithium-ion batteries use only one.
However, one challenge has been the formation of dendrites during the battery’s charging process.
Dendrites are tiny, tree-like structures of zinc that build up on the battery’s anode. Over time, these dendrites can pierce the separator between the battery’s positive and negative sides, causing short circuits and reducing the battery’s life. This issue has been especially difficult to solve in zinc batteries.
The research team came up with a solution by using copper oxide to control the formation of dendrites. Copper oxide helps zinc to deposit evenly across the surface of the anode, which prevents the formation of these dangerous dendrites.
When they tested batteries made with this new method, the team found that the batteries lasted ten times longer than traditional zinc batteries.
In the past, scientists tried to solve the dendrite issue by adding copper to the batteries. This helped guide the initial growth of zinc, but over time, dendrites would still form.
The new method involving copper oxide not only helps with zinc deposition but also creates a “scaffold,” or framework, that keeps the zinc from growing in disorganized patterns. This structure remains in place even after many charge and discharge cycles, keeping the battery stable.
Thanks to this development, the new zinc batteries can retain 80% of their capacity even after 3,000 charge-discharge cycles, making them much more durable than before. The batteries also showed a record-breaking energy storage capacity of 60 mAh/cm², and the technology works on large-area electrodes, making it suitable for commercial use.
Dr. Woo emphasized that this discovery could help make zinc batteries a real alternative to lithium-ion batteries. The team plans to continue their research to improve the manufacturing process and bring these safer, longer-lasting batteries to the market.
