Recovery of Waste Battery Materials Using Molten Salt Oxidation and Separation

Lithium-ion batteries provide a popular energy storage option due to their high energy and power density compared to other technologies and demand is expected to continue to grow. Most lithium-ion battery chemistries rely on cobalt and nickel oxides, both of which are fairly expensive and which the United States obtains primarily via imports. Despite this limitation, most lithium-ion batteries are discarded as waste and the materials unrecovered. CFD Research proposes to develop a molten salt oxidation (MSO) process to facilitate efficient removal and recovery of cathode active materials from a mixed battery waste stream. In addition, the MSO process will enable the recovery of other high value products (metallic copper and lithium) that are usually lost or require additional separation steps. The MSO approach will operate at lower temperatures and at smaller scales than typical pyrometallurgical processes, while utilizing fewer harsh chemicals than hydrometallurgical processes, allowing the MSO process to be remain cost effective even with uncertainty in future cathode compositions and price. The MSO salt will be chosen to be environmentally benign and the process optimized to enhance recovery. The process will be demonstrated at benchtop scale and a scale-up analysis will be performed.