Simulation-based life cycle assessment for hydrometallurgical recycling of mixed LIB and NiMH waste

The sustainable and competitive recovery of materials from spent batteries is becoming an urgent issue due to the increasing popularity hybrid fully electric vehicles. In this present study, flowsheet simulation was combined with life cycle assessment investigate environmental impacts a conceptual, experimentally proven hydrometallurgical battery recycling process, where nickel metal hydride (NiMH) waste used as reductant for lithium-ion (LIB) waste, synergistically improving extraction valuable metals both types. Various options sodium circulation in precipitation rare earths were considered different scenarios. results showed that main benefit process reduced consumption leaching chemicals. Of investigated management scenarios, crystallization sulfate found be most environmentally feasible option, allowing use Na chemical earth recovery. Significant potential reductions climate change, acidification, freshwater eutrophication, human toxicity also achievable when compared primary production metals, mainly high footprint cobalt production. Although further improvements possible, future availability NiMH may limit application described concept on industrial scale.