Feasibility assessment of remanufacturing, repurposing, and recycling of end of vehicle application lithium-ion batteries

Abstract

Purpose: Lithium-ion batteries that are commonly used in electric vehicles and plug-in electric hybrid vehicles cannot be simply discarded at the end of vehicle application due to the materials of which they are composed. In addition the US Department of Energy has estimated that the cost per kWh of new lithium-ion batteries for vehicle applications is four times too high, creating an economic barrier to the widespread commercialization of plug-in electric vehicles. (USDOE 2014). Thus, reducing this cost by extending the application life of these batteries appears to be necessary. Even with an extension of application life, all batteries will eventually fail to hold a charge and thus become unusable. Thus environmentally safe disposition must be accomplished. Addressing these cost and environmental issues can be accomplished by remanufacturing end of vehicle life lithium ion batteries for return to vehicle applications as well as repurposing them for stationary applications such as energy storage systems supporting the electric grid. In addition, environmental safe, “green” disposal processes are required that include disassembly of batteries into component materials for recycling. The hypotheses that end of vehicle application remanufacturing, repurposing, and recycling are each economic are examined. This assessment includes a forecast of the number of such batteries to ensure sufficient volume for conducting these activities.

Design/methodology/approach: The hypotheses that end of vehicle application remanufacturing, repurposing, and recycling are economic are addressed using cost-benefit analysis applied independently to each. Uncertainty is associated with all future costs and benefits. Data from a variety of sources are combined and reasonable assumptions are made. The robustness of the results is confirmed by sensitivity analysis regarding each key parameter. Determining that a sufficient volume of end of vehicle application lithium-ion batteries will exist to support remanufacturing, repurposing, and recycling involves estimating a lower bound for the number of such batteries. Based on a variety of forecasts for electric vehicle and plug-in hybrid electric vehicle production, a distribution of life for use in a vehicle, and the percent recoverable for further use, three projections of the number of end of vehicle applications batteries for the time period 2010 to 2050 are developed. The lower bound is then the minimum of these three forecasts. Multiple forecasts based on multiple sources of information are used to help reduce uncertainty associated with finding the lower bound, which is particularly important given the short time such vehicles have been in use.

Findings: The number of lithium-ion batteries becoming available annually for remanufacturing, recycling and repurposing is likely to exceed 3,000,000 between 2029 and 2032 as well as reaching 50% of new vehicle demand between 2020 and 2033. Thus, a sufficient number of batteries will be available. Cost benefit analysis shows that remanufacturing is economically feasible, saving approximately 40% over new battery use. Repurposing is likewise economically feasible if research and development costs for new applications are less than $82.65 per kWh for upper bound sales price of $150.00 per kWh. For a lower bound in R&D expenses of $50 per kWh, the lowest economic sales price is $114.05 per kWh. Recycling becomes economically feasible only if the price of lithium salts increases to $98.60 per kg due to a shortage of new lithium, which is possible but perhaps not likely, with increasing demand for lithium-ion batteries.

Research limitations/implications: The demand for lithium-ion batteries for vehicle applications through 2050 has a high degree of uncertainty. Repurposing applications are currently not fully developed and recycling processes are still evolving. There is a high degree of uncertainty associated with the cost-benefit analysis.

Practical implications: Lithium-ion batteries are a major cost component of an electric vehicle and a plug-in electric hybrid vehicle. One way of reducing this cost is to develop additional uses for such batteries at the end of vehicle application as well as an environmentally friendly method for recycling battery components as an alternative to destruction and disposal.

Social implications: The use of lithium-ion batteries in vehicles as opposed to fossil fuels is consistent with the guiding principles of sustainability in helping to meet current needs without compromising the needs and resources of future generations. Reusing entire lithium-ion batteries or recycling the materials of which they are composed further reinforces the sustainability of the use of lithium-ion batteries.

Originality/value: The results show that a sufficient number of batteries to support remanufacturing, repurposing, and recycling will be available. Remanufacturing is shown to be economically feasible. Repurposing is shown to be feasible under reasonable conditions on design and development. Recycling will likely not be economically feasible in isolation but will eventually be necessary for all batteries. Thus, the costs of recycling must be assigned to original vehicle use, remanufacturing and repurposing applications Furthermore, this effort integrates information from a wide variety of sources to show the economic feasibility of end of vehicle application uses for lithium-ion batteries.