The number of electric cars on our roads is set to increase dramatically in the coming years. The price of battery packs for electric drives will then fall as a consequence of the economies of scale alone. Nonetheless, lithium-ion batteries are likely to remain the most expensive component in electric vehicles due to the increasing requirements on power density and energy density. However, these energy storage devices still have a residual capacity of 70 to 80% of their original storage capacity when they come to the end of their service life after around 10 years. It would be a real shame to send lithium-ion batteries for recycling at this stage. So instead, they embark on a new life in a stationary storage system.
Experts estimate that the batteries can be profitably used for at least another ten years to temporarily store solar and wind energy and alleviate peaks in power production and consumption. Automobile groups and utility companies have recognized the potential here and have launched a number of projects to develop this new technology. One of the first large-scale technical applications was a grid energy storage system in Lünen, Germany. Around 1,000 battery systems from Smart electric cars manufactured by the project partner Daimler have been used as a capacity buffer in the power grid since 2016. And it has yielded surprising results: As charging/discharging cycles are more consistent in stationary storage operation, the usable capacity of the second-use batteries has increased by 0.3% since it became operational.
Other automotive companies are also preparing to keep increasing numbers of batteries once they have been retired from vehicles and give them a second life. For example, Renault is working together with an England-based manufacturer of domestic storage systems. The French automotive company systematically replaces the lithium-ion batteries in its vehicles as soon as their charging capacity falls below 75%. The long-term market leader is taking the batteries previously used to power the Renault Zoe before the conversion from 20 up to 41 kilowatt hours and supplying them for the production of small storage systems for private households. The second use of the batteries brings down the costs for Renault, and the manufacturer of the domestic storage system also saves around 30% compared with using new batteries. This price advantage is ultimately passed on to the customers.
The multi-story parking garage of Amsterdam’s Johan Cruyff Arena is home to a 3 megawatt energy storage system which came into operation a year ago. The xStorage system from Eaton and Nissan combines 85 brand-new and 63 second-use battery modules from the Nissan LEAF. It is one of the largest energy storage systems ever to be installed in a commercial building in Europe and contributes to a more environmentally friendly and efficient energy supply in Ajax Amsterdam’s home stadium. What’s more, it can also supply emergency back-up power during power failures and help to manage peak loads.
But we should also bear in mind that alongside the economic advantages, second-use storage systems have an ecological benefit. Compared with new batteries, they reduce the demand for critical raw materials such as nickel and lithium and bring down the amount of energy required to provide storage capacity.
Guided exhibition tours battery production also give answers regarding battery recycling and second use; Meeting point: ees Europe hall C1, PV and Battery Production Forum
PV and Battery Production Forum, hall C1, booth C1.550: battery life cycle will also play a role at the expert presentations