GM and ABB conducted a laboratory demonstration at the University of North Carolina campus in Raleigh that combined a bank of “used” EV batteries with an Inverter pack to produce 25 kilowatts of power for 2 hours. The 25/50 kWH pack could provide standby power to five homes. The batteries used in the demo were not really used batteries. The Chevy Volt warrants its batteries for 8 years or 100,000 miles and the car has not been on the roads for long enough to generate “used” batteries. The application , which is planned to be field tested in 2012 with help from the Electric Power Research Institute ( EPRI) aims to apply this Inverter to applications like storage batteries for renewable energy sources and as a standby power source connected to a transformer that feeds five homes on a street.
GM senior manager for battery life-cycle management , Pablo Valencia says that even after a 10 year use on the Chevy Volt car, the lithium ion batteries would still have 70 percent residual life that could well meet the utilities requirement of a 15 year further life for any standby power source they install. He also says that more spent batteries than needed could be used in the Inverter application to provide for any deficiencies in battery residual life. Valencia says that battery energy storage capacity declines in the first few years and then it “levels off”
Some battery researchers disagree.They say that as batteries age, they undergo changes in structure and chemistry that would make the performance hard to predict. Other critics point out that battery technologies are evolving fast and in 10 years when the EV used batteries become available in large quantity, then technology would make these batteries unattractive for use.
Nissan has also announced a partnership with Sumitomo Corporation to use spent EV batteries to store solar power. They have installed seven Leaf recharging stations at the Nissan Headquarters that have solar roof panels charging battery packs at the ground level.
