A recent study provides a comprehensive life cycle assessment (LCA) comparing the environmental impacts of industrial-scale LIB recycling with traditional mining supply chains. The research quantifies the energy consumption, greenhouse gas (GHG) emissions, and water use associated with both processes and identifies key areas for optimization.
Findings indicate that recycling end-of-life LIBs into battery-grade materials can reduce environmental impacts by at least 58%. The most significant reductions occur when recycling is optimized to produce mixed metal products rather than discrete salts. Furthermore, electricity consumption is identified as the primary contributor to environmental impacts in LIB recycling, with emissions varying up to five times depending on the energy source.
The study highlights that refining processes constitute the most significant environmental burden in conventional and circular supply chains. In conventional mining, refining accounts for over 57% of total environmental impacts, while in recycling operations, it dominates the overall carbon footprint. When comparing gate-to-gate processes, the production of battery-grade materials from conventional mining consumes 193.9 MJ of energy and emits 14.5 kg CO2-equivalent per kg of cathode material. In contrast, using recycled materials reduces these values by 88.7% for production scrap and 77.1% for end-of-life batteries.
One of the most promising insights from this study is the superior environmental performance of industrial-scale recycling operations, such as those implemented by Redwood Materials. The research demonstrates that hydrometallurgical (Hy) processes, combined with mechanical (Me) and reductive calcination (RC) pyrometallurgical techniques, result in lower emissions and energy consumption compared to traditional smelting-based recycling.
Electricity sources have a profound effect on the environmental footprint of recycling operations. In the study, substituting the Nevada Power Company grid (NEVP) with cleaner alternatives, such as the Bonneville Power Administration Transmission (BPAT) or a 100% renewable energy tariff, reduced GHG emissions by up to 93.3% for production scrap and 87.4% for end-of-life batteries. However, the trade-off between carbon emissions and water consumption remains a key consideration, as hydroelectric and geothermal power sources tend to consume more water despite their lower carbon intensity.
While conventional mining supply chains contribute significantly to environmental burdens through extraction and long-distance transport, circular LIB supply chains show a stark contrast. Conventional transport emissions for mined materials range from 3.68 kg to 6.4 kg CO2-equivalent per kg of metal, whereas transporting recycled LIBs to refinement facilities in localized collection networks reduces emissions by over 98%.
A case study of California’s LIB recycling infrastructure demonstrates that strategically located collection and processing facilities can further minimize transport emissions. Collection strategies employing shortest-route logistics significantly cut energy consumption and carbon emissions associated with LIB recycling.
The study underscores the urgent need for industrial-scale investment in LIB recycling infrastructure and policy incentives to support sustainable supply chains. Given that refinement remains the dominant contributor to emissions, targeted improvements in energy efficiency and process optimization are critical.
Governments and businesses can take the following actions to advance circular LIB supply chains: