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8.0 Remanu­facturing/​Repurposing

At end-of-life, there are three opportunities for EV batteries – remanufacturing, repurposing, and recycling. The following sections considers the former two, Section 9.0 covers the latter.

8.1 Remanufacturing

The second life application of the EV battery is dependent on its state-of-health (SOH) and remaining useful life (RUL). If the EV battery is still functioning with 70–80% of its initial capacity, then it can be remanufactured into a less energy demanding vehicle or repurposed for a different application such as an energy storage system (ESS).
Zhu J. et al. (2021). End-of-life or second-life options for retired electric vehicles batteries. Cell Reports Physical Science, 2. Retrieved from: https://www.sciencedirect.com/science/article/pii/S2666386421002484
 If the battery’s capacity is reduced due to damaged cells, then these cells could be replaced, and the battery can be re-used in an EV application.
Hantanasirisakul, K. & Sawangphruk, M. (2023). Sustainable Reuse and Recycling of Spent Li-Ion batteries from Electric Vehicles: Chemical, Environmental and Economical Perspectives. Global Challenges, 7. Retrieved from: https://onlinelibrary.wiley.com/doi/full/10.1002/gch2.202200212
 If the battery’s capacity is significantly reduced and the damaged cells cannot be replaced, it would not be suitable for remanufacturing or repurposing and therefore would be sent to a recycling facility instead. Additionally, due to the life spans of EVs becoming longer than expected, even if they have remaining capacity, it could make more sense to recycle them as the technology might have become outdated.
It is vital that the batteries undergo thorough inspections, detailed in Section 7.0, to evaluate their SOH and RUL before deciding the appropriate end-of-life route. Remanufacturing and repurposing prolong the usage of lithium-ion batteries. Remanufacturing is the most advantageous EOL scenario in terms of expanding the value and minimising life-cycle energy consumption and emissions. However, this option has the most stringent battery quality requirements. 
Remanufacturing involves refurbishing EV batteries, potentially by replacing faulty cells, and subsequently installing them in their original (automotive) applications, dependent on whether they have acceptable SOH. The remanufactured battery pack must be rigorously tested to ensure that it meets OEM specifications. Before the development of EV repair and remanufacturing capabilities, EOL EV battery packs were recycled to extract the raw materials, which could then be used in new cells. It used to be that the residual value of failed packs and the fully functional modules contained within were completely ignored. Due to the pressure of trying to reach net-zero targets and increased scrutiny around environmental performance, remanufacturing has rapidly progressed.
Autocraft (2023) What is EV battery remanufacturing and why it matters. Retrieved from: https://autocraftsg.com/news/insights/what-is-ev-battery-remanufacturing-and-why-it-matters/

Case Study: Spiers New Technologies

Spiers New Technologies (SNT) is a US-based company that provides 4R services (repair, remanufacturing, refurbishing and repurposing) for EVs, including Nissan Leaf, Chevy Bolt, Toyota Prius and more. They receive over 2,000 battery packs a month at their Oklahoma City facility, where they assess and remanufacture the batteries so that they can be put back into a vehicle as a warranty replacement.
 In 2018, SNT opened a new production centre in Ede in the Netherlands and launched a remanufacturing service for the European automotive and energy market.
Chen, M, et al. (2019) Recycling End-of-Life Electric Vehicle Lithium-Ion Batteries, Joule, 3, 2622-2646. Retrieved from: https://doi.org/10.1016/j.joule.2019.09.014

8.2 Repurposing

Previously, due to a shortage of new batteries, there was a large surge in companies focusing on the reuse of batteries. However, these companies could only get hold of small quantities of EOL EV batteries and were therefore not able to establish a successful business model. As the supply of new EV batteries is increasing, the prices are stabilising, which is reducing the demand for second hand batteries. While the recycling market is regulated in terms of emissions and safety, the reuse market is currently unregulated and is not considered as waste handling. This means that there is a possibility that smaller businesses can provide battery reuse services; this would not be possible for larger companies due to potential risks such as fire hazards etc.
Repurposing EOL batteries gives them a second life where they can be used in less-stressful applications, such as stationery storage.  Repurposing involves replacing damaged cells or modules and reconfiguring the modules or packs, including establishing new battery management systems, to accommodate a non-vehicle application.
Tao, Y. et al. (2021). Second life and recycling: Energy and environmental sustainability perspectives for high-performance lithium-ion batteries. Sci. Adv, 7. Retrieved from: https://www.science.org/doi/10.1126/sciadv.abi7633
An energy storage system is a technology that stores electricity to perform useful processes at a peak time. ESSs provide more stability when using renewable energy sources, such as solar and wind power. Energy suppliers can use an EOL EV battery as a backup power source for the grid. When there is an excess energy supply, the battery can be used for storage and utilised during peak times.
Hive Power (2022) Is Repurposing EV Batteries for Grid Energy Storage a Sustainable Plan? Retrieved from: https://www.hivepower.tech/blog/is-recycling-ev-batteries-for-grid-energy-storage-a-sustainable-plan
Vestas, a Danish wind turbine manufacturing company, have been working with a Swedish battery recycling company called Northvolt to develop technology to allow the storage of wind energy using repurposed EV batteries. As renewable energy cannot always meet demand with supply, the challenge is storing renewably generated electricity so that it can be delivered when required. The aim is to create a means to integrate battery storage solutions into wind turbines in order to guarantee more assurance and predictability in power output, which will allow greater grid stability.
Vestas (2017) Vestas and Northvolt partner on battery storage for wind energy to support the further integration of renewable. Retrieved from: https://www.vestas.com/en/media/company-news/2017/vestas-and-northvolt-partner-on-battery-storage-for-win-c2963503
 Vestas has also set up two shipping container units, each containing low-cost EV batteries (they used truck batteries due to the more standardised dimensions in comparison to car batteries). One unit is connected to a wind turbine and allows people to charge their EVs with green energy.
Technology Readiness Level
A technology readiness level (TRL) is a scale used to describe the maturity of a technology while it is being researched (TRLs 1-3), developed (TRLs 4-6) and deployed (TRLs 7-9).
9 – This technology is mature. It is already a well-established method of repurposing EOL EV batteries.
Risks
Deterioration – Unexpected deterioration of the battery pack can lead to thermal runaway, Joule heating (conversion of electric energy into heat) and internal short circuit.
 This can be dangerous in terms of fire risk but also means that ultimately the battery cannot be repurposed.

Explosion/Fire – Any process associated with EOL battery dismantling carries a risk of battery explosion or potential outbreak of fire.
Emissions
none
Strengths
Second life – Repurposing an EOL EV battery gives a second life application and allows them to be used for potentially another ~10 years.

Promotes renewable energy – Repurposing EOL EV batteries into ESSs helps to provide more stability when using renewable energy sources.

More cost-effective – Repurposing EOL EV batteries for use as ESSs is a cheaper option than creating a new battery pack.
Barriers to Circularity
Requires rigorous testing – Testing/screening is required to check SOH and RUL of battery before determining how/if it can be reused or repurposed. It must also undergo testing once it has been repurposed. Technical standards for evaluating and testing EOL EV batteries have not yet been properly established as there are several different battery designs on the market, making it difficult to determine safe criteria.

Market perception – There is a complex market for repurposed EV batteries due in part to challenges related to consumer acceptance of reused batteries. There are also a number of other potential obstacles, such as high collection and transport costs, etc., that hinder the development of a healthy and long-term market for repurposing EOL EV batteries.

Regulations/Legislation – Clear and comprehensive regulations and policies have yet to be established in Europe for the reuse and repurposing of EV batteries. Robust legislation would be beneficial in creating a healthy reuse market and would encourage the remanufacturing of EV batteries to allow circularity.
Chen, J. et al. (2023). Repurposing EV Batteries for Storing Solar Energy. Engineering, 1. Retrieved from: https://doi.org/10.1016/j.eng.2023.09.002
Applicability to Nordic Context
Repurposing EOL EV batteries is already being carried out across the Nordic countries as it is a well-established process.

Case Study: Evyon

Evyon is a Norwegian company that provides a modular direct current (DC) battery energy storage solution based on repurposed EV batteries for system integrators to incorporate into a range of viable solutions. In 2022, Evyon started working with Mercedes-Benz Energy to maximise the value of EV batteries by repurposing them into energy storage systems.
Evyon (2023). Evyon Industrial | An automotive-quality and scalable solution for system integrators. Retrieved from: https://www.evyon.com/product/
Nordic Council of Ministers I www.norden.org/publications I pub@norden.org