Scientists have developed a safe and economical water-based rechargeable battery that addresses the limitations of lithium-ion batteries currently used in energy storage systems (ESS). Their innovation lies in a composite catalyst composed of manganese dioxide and palladium that converts dangerous hydrogen into water while maintaining safety and performance. This breakthrough opens the door for the commercialization of these batteries in ESS and other industries, providing a more economical and safer alternative to existing technologies.
This summer, Earth is experiencing extreme weather patterns, including severe heat waves and heavy rainfall. In these challenging times, embracing renewable energy and strengthening related infrastructure as a strategy to protect the planet is more urgent than ever. However, this approach faces significant challenges due to the unpredictability of renewable energy generation, as it relies on uncertain variables such as unstable weather conditions.
Therefore, there is an increasing demand for energy storage systems (ESS) that can store and supply power when needed. However, the lithium-ion batteries (LIB) currently used in ESS are not only expensive but also prone to fire hazards, so there is an urgent need to develop cheaper and safer alternatives.
An innovative technology safely converts hydrogen gas into water, improving battery safety. This advance paves the way for the commercialization of more economical and safer water-based rechargeable batteries.
Research progress of water-based rechargeable batteries
A research team led by Dr. Oh, Si Hyoung of the Energy Storage Research Center of the Korea Institute of Science and Technology (KIST) has developed a highly safe water-based rechargeable battery that can provide a timely alternative that meets cost and safety needs.
Despite the lower achievable energy density, aqueous rechargeable batteries offer significant economic advantages because their raw material costs are much lower than LIBs. However, the hydrogen produced by the decomposition of parasitic water will cause the internal pressure to gradually increase and eventually exhaust the electrolyte, which poses a huge threat to the safety of the battery and brings difficulties to commercialization.
Overcoming safety challenges in battery technology
Until now, researchers have often tried to circumvent this problem by installing surface protection layers to minimize the contact area between the metal anode and the electrolyte. However, in most cases, corrosion of the metal anode and the accompanying decomposition of water in the electrolyte are inevitable, and the continuous accumulation of hydrogen can cause potential explosions in long-term operation.
In order to solve this critical problem, the research team developed a composite catalyst composed of manganese dioxide and palladium, which can automatically convert the hydrogen generated inside the battery into water, thus ensuring the performance and safety of the battery.
Under normal circumstances, manganese dioxide does not react with hydrogen, but after adding a small amount of palladium, the hydrogen is easily absorbed by the catalyst and regenerated into water. In prototype cells loaded with the newly developed catalyst, the internal pressure of the cells was maintained well below safety limits, and no electrolyte depletion was observed.
Impact on future energy storage
This research result effectively solves one of the most worrying safety issues in water batteries and takes a big step towards the commercial application of ESS in the future. Replacing lithium batteries with cheaper and safer water batteries will even trigger rapid growth in the global ESS market.
Dr. Oh, SiHyoung of the Korea Advanced Institute of Science and Technology said: "This technology is based on a built-in active safety mechanism that tailors safety strategies for water-based rechargeable batteries, through which risk factors are automatically controlled. In addition, it can be applied to various industrial facilities where hydrogen leakage is one of the major safety issues (such as hydrogen stations, nuclear power plants, etc.) to protect public safety."
Compiled source: ScitechDaily