Rebaba Raises $4.6M to Give Retired EV Batteries a Second Life

Stockholm-based Rebaba, an energytech startup founded by Paula Runsten former Northvolt engineers, has raised $4.6 million in Seed funding to tackle one of the growing challenges of the electric vehicle industry: what to do with batteries once they are no longer suitable for use in vehicles.

The funding round was led by Sistafund, with participation from EIT Urban Mobility, existing shareholders, and several new European investors. The company plans to use the fresh capital to scale its technology and accelerate the deployment of second-life battery storage solutions.

Giving EV Batteries a Second Life

EV batteries may no longer deliver the performance required for vehicles after years of use, but that does not necessarily mean they are finished.

Rebaba is building technology that allows these retired batteries to be tested, repurposed and deployed for stationary energy storage. Instead of going directly to recycling, batteries can continue generating value in applications where their remaining capacity is still useful.

This approach could help extend battery lifespans while reducing waste and making energy storage more accessible.

Meet the Founders

Rebaba was co-founded in 2023 by Paula Runsten and Felix Kruse, both of whom previously worked at Northvolt.

Paula Runsten, Rebaba’s co-founder and CEO, brings extensive experience in battery technology and electric mobility. Before launching Rebaba, she worked on battery prototypes at Northvolt, contributed to the digitalisation of its production operations, tested electric vehicles at Tesla, and was involved in the development of a self-driving carbon-fibre electric Formula car.

Felix Kruse, Rebaba’s co-founder and CTO, met Runsten while they were studying and later worked alongside her at Northvolt. Together, they identified a clear gap in the market: large numbers of retired EV batteries were becoming available, while demand for stationary energy storage was growing globally.

Why Second-Life Batteries Matter

As the number of electric vehicles on European roads continues to grow, the supply of used EV batteries is expected to increase significantly.

Rather than treating these batteries purely as waste, companies like Rebaba are exploring ways to keep them in circulation for applications such as stationary energy storage and renewable-energy integration.

The broader second-life battery market has attracted increasing attention because repurposed batteries can potentially offer a lower-cost alternative to newly manufactured storage systems.

What’s Next for Rebaba?

With the new funding, Rebaba is looking to scale its operations, develop its second-life battery technology and expand the use of repurposed EV batteries across Europe.

The company’s vision is simple but important: make batteries last longer, extract more value from the resources already produced, and help build a more circular energy system. 🔋♻️