Research shows that the performance of lithium batteries using recycled positive electrodes is comparable to that of batteries using new materials

While the electric vehicle battery recycling industry is growing, it is still difficult to get automakers to use recycled materials. "People often think that recycled materials are inferior to virgin materials," said Yan Wang, a professor of mechanical engineering at Worcester Polytechnic Institute. "Battery companies are still reluctant to use recycled materials in batteries."

(Image credit: Worcester Polytechnic Institute)

New research conducted by Wang and his research team, which also includes researchers from the U.S. Advanced Battery Consortium (USABC) and battery company A123 Systems, shows that batteries using recycled cathodes are as good as or better than batteries using new leading materials,media reported.

The research team tested batteries with recycled NMC111 cathodes, the most common cathodes, which contain one-third each of nickel, manganese and cobalt. These cathodes were made using a patented recycling technology. Currently, Battery Sourcers, a startup co-founded by Wang and others, is working to commercialize the process. The recycled materials exhibit a more porous microstructure, which makes it easier for lithium ions to enter and exit. The results showed that the energy density of such batteries was similar to that of batteries using commercial cathodes, while the cycle life was extended by 53%.

The tests were conducted on an industrial scale, but recycled batteries were not tested in vehicles. The researchers built an 11 ampere-hour industry-standard soft-pack battery filled with materials with the same density as electric vehicle batteries. Engineers at A123 Systems completed most of the testing in accordance with the draft of the U.S. Advanced Battery Consortium (USABC) to meet the commercial viability goals of plug-in hybrid vehicles. The results prove that recycled cathode materials are a viable option to replace virgin materials.

Battery Resources' recycling technology can produce a variety of ready-to-use NMC cathode materials according to the needs of automobile companies. Therefore, selling this recycled material may be profitable. For recycling companies, this is difficult to do. The researcher said: "We are the only company that produces cathode materials. Other companies only output elements with lower added value."

The technology involves shredding the battery to remove the steel casing, aluminum and copper wires, plastic and soft packaging materials for recycling. The remaining black matter is dissolved in a solvent to filter out graphite, carbon and impurities, or chemically separated. Nickel, manganese and cobalt are mixed in the required proportions through patented chemical technology to make positive electrode powder.

Battery Resources already sells its recycled materials in small quantities to battery manufacturers. In 2022, the company plans to create its first commercial plant, which is expected to be able to process 10,000 tons of batteries. In September this year, the company raised $70 million and plans to launch two more plants in Europe by the end of 2022.