Lithium-ion batteries are a key technology in decarbonizing the transportation and electricity sectors, yet the use of critical materials, such as cobalt, nickel, and lithium, leads to environmental and social impacts. Reusing, repurposing, and recycling batteries mitigate these impacts by extending their lifespan and reducing reliance on virgin materials. Innovation that reduces demand for these problematic materials and increases battery efficiency also reduces impacts. Two examples of this technological innovation include, 1) the development of energy-dense cathode chemistry containing less cobalt, a material with high social and environmental impacts; and 2) the use of columnar silicon thin film anode, which results in increased energy density compared to the commonly used graphite anode.
This research assesses whether these technological innovations change the currently understood waste hierarchy, which prioritizes reuse or repurposing prior to recycling. This is of interest because retired high-cobalt batteries could supply their constituent materials sooner if recycled immediately and be used in low-cobalt, higher-performing batteries. The assessment considers the life cycle environmental impacts of two end-of-life management routes for a high-cobalt lithium-ion battery: first, recycling the battery immediately after the first use life to produce a new, and less material-intensive battery, and second, repurposing the battery for a stationary storage application followed by recycling. Findings show that battery reuse reduces life cycle environmental impacts relative to immediate recycling. Thus, from an environmental perspective, the waste hierarchy holds, and steps to retain the batteries in their highest value use, such as through repurposing, should still be prioritized.