Honda has developed a new process, the first process of its kind, for recycling rare earth metals from nickel-metal-hydride (NiMH) batteries, allowing the material to be used in building new NiMH batteries.
The rare earth metals recycling process Honda developed, in collaboration with Japan Metals & Chemicals, is the world’s first mass-production recycling process to extract rare earth metals from nickel-metal hydride batteries for new nickel-metal hydride batteries. So far, Honda has been extracting an oxide containing rare earth metals from used nickel-metal hydride batteries at the plant of Japan Metals.
According to Honda, using molten salt electrolysis they can extract over 80% of rare earth metals from used batteries at better than 99% purity, which is the same as traded from the mines after refining. The extracted metals are then used to make new electrodes in new batteries, reducing the required new materials to less than 20%.
Recycling, though, reduces the need to mine the original materials, such as aluminum, which can often be recycled 100% and turned into new aluminum products, requiring less time and energy, and therefore greenhouse gas emissions, than using raw aluminum ore.
The first batches of batteries that the process was applied to, were batteries from 386 Honda hybrid vehicles that were disabled by the Great East Japan Earthquake and subsequent tsunami. Honda plans on expanding the recycling program to include other sourced of rare earth metals, including electric motors and used batteries from dealers and scrap yards.