Open Chevy Volt battery pack. (via GM)
What happens to a 435 lb (197 kg) battery after it gets old?
GM and fellow Chevy Volt owners may soon get some residual value back from their electric vehicles. GM and Swizz company ABB have found a way to use 5 spent Chevy Volt batteries to create a community electric storage system.
When first installed, Volt lithium-ion batteries, composed of 288 cells making up 9 modules, are capable of 16 kWh and 111 kW of power. But after an estimated 10 years of use, the batteries lose 30% of their charge and are no longer suitable for Volt engines; however, GM and ABB realized there was still a lot of potential available, no pun intended, so they modified the T-shaped battery pack and connected 5 batteries together.
They found this setup could provide 50 kWh of electricity, enough for 3-5 average American homes for 2 hours. In 2013, the Charlotte, N.C. company, Duke Energy, will begin tests by hooking a battery pack to the grid via a transformer capable of serving around 4 houses and inverters manufactured by ABB. The batteries are capable of working at single phase or three phase at a round-trip efficiency of about 85-86%. Since each battery is only operating around 5 kW, they can be air cooled as opposed to liquid cooling required in the Volt. GM will continue to provide maintenance for the batteries just as they do with Volt owners.
This system could be charged during off-peak hours and provide energy during peak charge hours for a cheaper cost. It could also serve as back-up during outages, and fill gaps in lapses in renewable energy like solar and wind. This community energy system will power on automatically, delivering 100% of its power to homes. Utility companies can manage the battery remotely, making the system even more attractive. GM estimates these batteries will see a 10 year life in cars plus an additional 10 years as community storage devices.
GM literally lit up its Electrification Symposium in California earlier this month, using a prototype of the battery packs to power lights and AV equipment. GM is also due to unveil the Spark EV at the LA Auto Show and their announcement that future Chevy, Buick, GMC and Cadillac vehicles will also look to be reused means that Spark batteries will probably share the same fate as used Volt batteries.
Toyota and Tesla should hop in this initiative too.