Engineers at Rice University have developed a process that recovers lithium from electric vehicle battery waste using electricity and water, bypassing the need for strong acids and complex chemical steps. The method employs the same reaction as conventional battery charging, driving lithium ions from spent cathodes into water, where they combine with hydroxide to form high-purity lithium hydroxide.
Sibani Lisa Biswal explained, “If charging a battery removes lithium from the cathode, why not use that same reaction to recycle?” Using a compact electrochemical reactor, the team efficiently separated lithium and produced the lithium salt preferred by manufacturers.
In experiments, the zero-gap membrane electrode reactor processed industrial battery waste, achieving a recovery rate of almost ninety percent in a thousand hours and producing lithium hydroxide with a purity of more than ninety-nine percent. The process required only one hundred and three kilojoules of energy per kilogram of waste, far below conventional acid leaching operations. The system was scaled up to eight square inches and processed fifty-seven grams of industrial black mass supplied by TotalEnergies.
Haotian Wang added: “Producing high-purity lithium hydroxide directly shortens the path back to new batteries. That means fewer processing steps, less waste and a more resilient supply chain.”
Tests showed the technology works with different battery chemistries, such as lithium iron phosphate and nickel-manganese-cobalt varieties. The researchers also demonstrated continuous roll-to-roll processing of electrodes, eliminating the need for manual handling.
Future goals include building larger reactor stacks, improving membrane performance and refining post-processing to further reduce energy consumption.
Biswal stated, “We’ve made lithium extraction cleaner and simpler. Now we see the next bottleneck clearly. Address the concentration and you unlock even better sustainability.”
Research report:A direct electrochemical Li recovery from spent Li-ion battery cathode for high-purity lithium hydroxide feedstock
