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STABL Energy implements first second-life storage system with project partners

Battery storage is a key to the successful energy transition. They can store surplus electricity from solar and wind power and make it available when the sun is no longer shining or the wind is not blowing.

At the same time, batteries are needed to meet the high demand for electric vehicles. However, the batteries in the vehicle have a limited service life – after 10 to 15 years, they no longer meet the requirements of mobility, but can theoretically still be used in stationary applications for the energy transition. So you give them a second life. Therefore, they are also called second-life batteries.

The challenge of second-life storage

However, recycling these second-life batteries has some technical hurdles: conventional storage is a chain of many battery modules. This static chain of battery storage, like any chain, has the property that the weakest link determines performance. Specifically, the reservoir with the lowest energy content determines the removable capacity. However, used vehicle batteries have different conditions after many years, for example due to different loads, but also production tolerances. Therefore, the conventional approach of stationary storage is not suitable for second-life.

To this end, STABL Energy has developed an innovative solution that makes battery storage more efficient and safer and enables the integration of discarded batteries from electric vehicles in high volumes. The STABL technology can easily handle the sometimes very different residual capacities of the battery modules from the vehicle, allowing the batteries to be used for longer. STABL Energy’s first product – the SI100 – connects the battery modules to the power grid, entirely without an inverter.

First second-life storage facility with STABL technology now in operation

Now, for the first time, STABL Energy has incorporated its technology into a storage facility. The storage consists of 24 used battery modules from old KIA Soul EV and has an energy content of 72 kWh. Together with the project partners from encore, a corporate startup from DB Bahnbau Gruppe GmbH, inno2grid and Dellcon, the project was realized at the Euref Campus and has since been on public display.

“We are happy to now be able to show our product in a real environment outside the lab. With the certifications for our product now completed, we are starting series production and letting as many companies as possible participate in the energy transition,” says Co-Founder and Co-CEO Dr. Nam Truong.

The storage facility is another milestone after winning the ees AWARD 2022 at The Smarter E Europe in Munich. STABL Energy is planning further projects with its partners for various customers over the next few years. In addition to rail-related applications such as buffering charging stations at train stations, projects are also being planned with commercial and industrial companies to optimize their power consumption or provide an emergency power supply. “This is how we extend the life cycles of car batteries and want as many companies as possible to participate in the energy transition,” Truong said.

More information about the project can be found in the press releases of Deutsche Bahn and KIA Europe.