Researchers Develop Method to Multiply Lifespan of NiMH Batteries

Mar, 2021 - By WMR

Researchers developed a method to increase the lifespan of rechargeable NiMH batteries.

This study was conducted by the researchers at Stockholm University. Batteries based on nickel-metal hydride (NiMH) along with an aqueous electrolyte are both eco-friendly and safe. The NiMH battery is developed from the nickel-hydrogen battery (NiH2). NiH2 batteries are found to have better lifespan when compared to other types of battery due to which they are used in satellites in orbit in space. However, structures of these batteries are impractically large, as hydrogen is stored in gas tanks. In this study, researchers have developed a technique to achieve the same long lifespan for NiMH batteries as in the large NiH2 batteries.

In a NiMH battery, hydrogen is bound in the metal alloy. Although the solution is effective, the battery ages, as it dries out when the alloy slowly corrodes and consumes its water-based electrolyte. The corrosion also interferes with the internal balance between the electrodes in the battery. The breakthrough was when researchers found that they could counteract the aging process almost completely by adding oxygen, which restores the lost electrode equilibrium and replaces the lost electrolyte.

Therefore, with the right balance of oxygen and hydrogen, a lifespan is achieved, which is better than all other batteries that are present in the market currently. Dr. Yang Shen said, “This new battery technology is a major step along the way. Right now, Sweden is a world leader in the segment of rechargeable NiMH batteries.”