As the demand for electric vehicles, cell phones, and computers continues to grow, so does the demand for lithium used in lithium-ion batteries. While this soft, alkali metal known as “white gold” is abundant in certain countries, the mining process and safety issues are of concern to researchers. One such researcher is Ying Wang, associate professor, mechanical engineering, LSU, who is using a board of regents grant to design a non-metal rechargeable battery that could one day replace lithium batteries on Earth and in space.
“Lithium-ion batteries have good performance but several serious issues,” Wang said. “It’s not sustainable and is very expensive, and the U.S. does not have deep reserves for lithium. Also, if you are extracting lithium from mines, you are using a tremendous amount of water, which has a severe impact on the environment.”
Wang and her group of LSU mechanical engineering students have been working on a non-metal battery with a water-based electrolyte that is safer than an electrolyte in a lithium battery, which uses flammable and toxic organic solvents.
“Lithium is not a stable metal, and the organic electrolyte in a lithium-ion battery could be flammable,” Wang said. “There have been lithium battery explosions in the news. This is a recurring problem because when lithium batteries fail or overheat, they release flammable, toxic gases that can spark a fast-spreading fire. My group is designing an ammonium-ion battery that is much safer, lighter, more affordable, and can be biodegradable. It can also be made thin and flexible, so it can twist and bend.”
Wang has spoken with NASA personnel about the battery and its potential use in space.
“NASA’s future space-exploration systems require safe, high-power-density, high-energy-density batteries,” Wang said. “Although lithium-ion rechargeable batteries have commonly been used in space systems, the safety issues cause concern and hinder their future applications.”
Wang’s ammonium-ion battery has an aqueous electrolyte containing high-concentration salts that result in a significantly depressed freezing point for operation at sub-zero temperatures in space systems. The anti-freezing electrolyte can be simply prepared by dissolving ammonium salt in water. The salt concentration will be varied and optimized to achieve the lowest freezing point, maximized ionic conductivity, and electrochemical performance of the battery. The battery will be tested under extreme conditions as is required by NASA.
“This study is expected not only to open a new direction of research on non-metal batteries but will also enhance NASA research and technology while contributing to the overall research infrastructure, science and technology capabilities, diversity in higher education, and economic development of Louisiana,” Wang said
Editor’s Note: This article originally appeared on the LSU College of Engineering website.
