There’s a new type of battery that can store and produce electricity with seawater. It was developed at the Ulsan National Institute of Science and Technology (UNIST) in South Korea. This type of battery uses sodium, which is an abundant element. It’s cheaper than lithium, and it’s environmentally safe. Sodium also reduces the risk of fire.
Seawater batteries extract sodium ions from water when it is charged with electrical energy and stores them in the cathode compartment. They don’t use an external power supply or auxiliary loads. This type of battery can be used as an emergency power source for ships and nuclear power plants. They can also be used in the home and industry as an energy storage system.
The disadvantage of seawater batteries is that they have low electrical output. Researchers at UNIST are working to solve this problem by optimizing cell geometry. The goal is to increase the charge rate by 20 Wh, which is more than a small smartphone battery, which has a charge rate of 10 Wh.
UNIST has partnered with Korea Electric Power Corporation (KEPCO) and Korea East-West Power Company Ltd. (EWP). KEPCO and EWP is investing 3 billion won over the next two years. Since 2014, UNIST has received 7 billion won in government grants.
The lead researcher, Youngsik Kim, has started his own company (4 to One) and is selling coin-shaped seawater batteries and test kits. The solid ceramic electrolyte synthesis technique used to make seawater batteries was shared with a local company (Ce&Chem Co. Ltd.) and they have produced 100,000 electrolytes each year.