The programme is managed by the Fraunhofer Innovation Platform at the University of Twente (FIP-AM@UT) and aims to strengthen regional innovation by supporting companies in developing cleaner and more resource-efficient manufacturing solutions. Within this program, ReLAB is one of several practical projects that put circular thinking into action by showing how existing materials can be used for much longer instead of being thrown away.
A major problem ReLAB addresses is that many lead-acid batteries are being discarded far too early. Lead-acid batteries, widely used in cars, industry and backup systems, are highly recyclable, with up to 99% of their materials recoverable. But recycling often happens long before these batteries are actually worn out. Many are melted down even though the issues they show can often be fixed. This leads to unnecessary waste, high energy use in the smelting process and extra CO₂ emissions from producing new batteries to replace them.
ReLAB takes a different approach. Instead of sending these batteries straight to recycling, the project develops a practical method to test which batteries still have life left in them and can be restored. The team uses simple diagnostic checks to understand a battery’s condition and then sorts them into three groups: ready to use, repairable or not suitable for reuse.
For batteries that can be repaired, several restoration techniques are applied. These include charging methods that help remove internal build-up, refreshing or adjusting the internal fluid and balancing the cells so they work more evenly again. In some cases, the batteries need extra attention to bring all cells back to similar levels, but these steps often give them a meaningful second life.
To show the approach works in real situations, the team built a demonstration system using a set of restored batteries. This system was safely connected, equipped with monitoring tools and then tested in two practical setups: supporting solar energy storage at the Advanced Manufacturing Centre at the University of Twente and providing electricity to a small off-grid tiny house. Both tests showed that restored batteries can perform reliably in everyday use.
The results were encouraging. Laboratory tests and real-world trials showed that many batteries can be successfully restored and reused, achieving strong and stable performance. When the team inspected an industrial batch of used batteries, around half could potentially be reused or repaired. This translates into several hundred kilowatt-hours of storage capacity that would otherwise have been lost.
The environmental benefits are also clear. Every restored battery reduces the need to manufacture a new one, and this alone can lower CO₂ emissions by an estimated 12% to 18% per battery compared to making a new unit. Reuse also cuts down on transport and reduces the handling of hazardous materials. This approach fits well with the circular manufacturing goals promoted within the CMSP framework.
Beyond the environmental impact, the practical uses are wide-ranging. Second-life lead-acid batteries are well suited for applications where stable but moderate energy use is expected, such as backup systems in factories, small renewable-energy setups or local grid-support solutions. Because the system is modular, it can be scaled up or down depending on energy needs, making it flexible and cost-effective for regional companies.
Riwald Recycling is now preparing a full life-cycle assessment and feasibility study to explore how this approach can be expanded on an industrial scale.
Looking ahead, ReLAB shows that giving batteries a second life is both realistic and worthwhile. By combining smart testing with simple refurbishment steps, valuable battery capacity can be saved rather than wasted. With further development and long-term testing, this approach could support a local market for second-life energy storage, strengthen energy resilience in the region and create new circular-economy opportunities for companies in Twente.
