Old EV batteries can increase renewable power use while reducing resource demand – agency

Making greater use of old electric vehicle (EV) batteries could greatly help reduce waste and stabilise the power grid in the shift towards renewable power, the German Renewable Energy Agency (AEE) said in an analysis. So-called second-life batteries could be taken from EVs once they drop below 80 percent of their initial capacity, a threshold that makes them difficult to use for transport purposes but still allows them to serve well as stationary power storage units, the AEE said. This would not only prolong each battery’s life cycle, but could also help save part of the 1.4 percent of renewable power produced in Germany in 2022 that had to be capped due to insufficient grid capacity. “We simply can no longer afford it as a society to let go off renewable electricity in this way,” AEE head Robert Brandt said. Expanding the grid to absorb more renewable power will be indispensable, Brandt said. However, more renewable power could be used for charging electric cars or heating if it is stored in second-life batteries whenever it is available. Municipalities could use large-scale solutions based on using old batteries and integrate these into their grid planning, the agency said. Moreover, they could be used as emergency storage units for critical infrastructure, including hospitals, fire departments or sewage plants. "Reusing batteries that already served in EVs offers a sustainable option for saving excessive energy and use it during times of high demand," Brandt argued. In addition, this measure could also help reduce the need for new materials for battery production.

Rising demand for e-cars has triggered growing concerns about their batteries' environmental and human costs. Scaling up reuse and recycling will also be key to making the shift to low-emission mobility truly sustainable, experts agree. At the same time, Germany is in need of rapidly expanding its storage capacities for renewable power to ease the burden on lagging grid expansion and enable the country to bridge periods of low renewable power output.