BMW Group recently announced the start of a new research project on the secondary use of EV batteries that will be conducted with Vattenfall.
Earlier, both companies cooperated on EV fleet tests, so this alliance is just another extension in the electric vehicle area.
The main topic of the project is to research opportunities of secondary use of high-voltage EV batteries from MINI E and BMW ActiveE in stationary power storage applications.
Stationary battery packs that lost some original capacity, but still are too powerful to be sent for recycling, can be used as buffer power at fast charging stations or for renewable power sources, grid stabilization or as back-up.
According to the press release, BMW and Vattenfall expect that lithium-ion batteries — after the end of their life cycle in an electric vehicle — still have storage capacity of around 80 percent and work "over many years" as stationary packs.
Results from this project could be very interesting, especially since MINI E and BMW ActiveE use different li-ion cells. In MINI E, we have 18650 cylindrical type and in BMW ActiveE/BMW i3, laminated ones.