A recent life cycle analysis of lithium-ion (Li-ion) batteries highlights the importance of recycling to reduce their environmental and health impacts. The study, released last month by the US EPA, examined a range of battery chemistries including:
• lithium-manganese oxide
• lithium-iron phosphate.
Batteries that use cathodes with nickel and cobalt (both rare), as well as solvent-based electrode processing, were found to have the highest environmental impacts. These include resource depletion, global warming, ecological toxicity, and human health impacts.
The largest impacts are those associated with the production, processing, and use of cobalt and nickel metal compounds, which according to the report may cause adverse respiratory, pulmonary, and neurological effects in those exposed. The toxicity impacts of lithium are also highlighted.
The report notes that recovery of metals at end of life can significantly reduce these life cycle impacts. This is because the extraction and processing of virgin materials are key contributors to impacts for all battery chemistries. Three recycling processes were analysed:
• hydrometallurgical recovery
• pyrometallurgical (high temperature) recovery
• ‘direct recycling’, which allows for a higher percentage of recovered battery materials but is still in the pilot stage.
It may also be possible in future to refurbish batteries at end of life for use in computers or other electronics, or to rejuvenate them with new electrolyte.
Historically battery recycling has focused on recovery of cobalt because its value has risen in response to increased demand for battery manufacturing. However, the use of cobalt in batteries is projected to decline as battery technology evolves.
In addition to cobalt, battery recyclers may recover lithium, nickel and other materials. Demand for lithium is expected to grow significantly due to increased use of Li-Ion batteries in electric vehicles. Recycling will help to preserve virgin resources and reduce their environmental impact.
The report identifies a number of opportunities to improve the life cycle impacts of Li-ion batteries, including:
• increasing the lifetime of the battery
• reducing cobalt and nickel use
• incorporating recovered material in the production of the battery.
For more information:
Shanika Amarakoon, Jay Smith and Brian Segal (2013), Application of life cycle assessment to nanoscale technology: lithium-ion batteries for electric vehicles, Report by Abt Associates for United States EPA, 24 April
Download the report here.