MNTRC Newsletter Vol. 20, Issue 3: Winter 2013

Li-Ion battery disposal: turning a negative into a positive

Charles Standridge, PhD, Professor and Assistant Dean

GVSU News – Recently, the federal government approved vehicle performance standards that include a requirement for 54.5 miles per gallon (MPG) by 2025 and a greenhouse gas standard of 163 grams of carbon dioxide equivalent per mile in the same year. One way to meet these standards is to increase vehicle electrification by a variety of means. These include improving existing electric vehicles and plug-in hybrid electric vehicles, as well as creating new means such as the increased presence of start/stop technology.

Lithium ion batteries are an efficient energy storage mechanism, and their use will continue to expand as vehicles are electrified. A fundamental question remains. What is to be done with these batteries once they reach the end of their useful life? There are three possibilities:

  • Remanufacturing for reuse in vehicles. Replacing damaged cells within the batteries is an effective remanufacturing strategy.
  • Repurposing by reengineering a battery for a non-vehicle application. This usually means developing a different control system for the battery and repairing any damage, as in remanufacturing.
  • Recycling those batteries. That means disassembling each cell in the battery and safely extracting the precious metals, chemicals, and other bi-products. These are sold on the commodities market or re-introduced into a battery manufacturing process.

Assessments show promise.

The industry has made progress developing each of these after-vehicle application areas. In addition, it has been able to assess how many of these batteries would be available over time, as well as the economic feasibility of each alternative listed above.

A forecasting model for the number of end-of-vehicle-application lithium ion batteries was used to ensure sufficient supply to support remanufacturing, repurposing, and recycling. The model considered multiple, wide ranging vehicle demand forecasts, a probability distribution of vehicle application life, and a percent useable factor at the end of vehicle life.

Results showed that by 2035, the number of these batteries would range from 1.376 million to 6.759 million, with a middle forecast of 3.773 million. These numbers predict sufficient batteries to justify remanufacturing, repurposing, and recycling. More importantly, the number of these batteries is approximately between 55% and 60% of the number of batteries needed for new production, further supporting the opportunity for remanufacturing. In 2050, this range is predicted to be approximately 70% to 85%, showing a growing opportunity for remanufacturing. These results also indicate that the industry should develop repurposing and recycling processes as well.

Old batteries become new.

A cost benefit analysis was done independently for each of the three types of processing. Costs were included for operations, transportation, material handling, infrastructure development, and facility development. Benefits were many. They included avoiding costs for battery storage and production of new batteries, as well as sales of repurposed batteries and sales of recovered materials in recycled batteries.

Remanufacturing was shown to be cost effective primarily because it avoided costs of producing new batteries when a remanufactured battery could be used instead. Repurposing is a less well-defined application area. However, repurposing was shown to be economical when the development costs of repurposing applications were less than $87 per kWh. Recycling in isolation is not economical, as lithium ion batteries are composed of relatively inexpensive materials. However, recycling can support closed-loop supply chains reusing battery materials for new battery production. It’s also environmentally responsible and sustainable.