Image: STABL

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.