The spiritual among us will view Sumitomo and Nissan’s installation of its first-ever used-electric-vehicle-battery storage as a bit of divine reincarnation. But the idea is quite logical and practical. The two companies formed the 4R Energy Corporation in late 2010 and have now installed what they call the world’s first “large-scale power storage system” using exclusively used batteries from battery-electric vehicles in Osaka, Japan.

The system uses 16 electric-vehicle batteries to create what’s called a “smoothing effect” on the power output of a nearby solar farm by storing excess energy generated by the panels during sunnier times, then sending it back to the system when it is sun-constrained. Yes, that’s a fancy word for dark.

Spurred by Japan’s Ministry of the Environment, Sumitomo and Nissan announced the collaboration, whose four Rs stand for “Reuse, Resell, Refabricate and Recycle,” in 2009 and launched it a year later. Nissan, which was obviously trying to boost resale value for its battery-electric Leaf at the time by finding a money-generating home for its used-up battery packs, estimated at the time that sales of the Leaf battery-electric would generate 50,000 battery packs available for the secondary market by 2020…

Toyota is also investing time and money towards similar low-carbon, recycling targets – from two different directions: selling disused Prius batteries for low-cost electricity storage and solar backup to their car dealers and a much grander project at Toyota City’s EcoFul Town in Japan. The latter a holistic solution involving home-building, transportation and solar-generated electricity.

Neither of which takes anything away from the Nissan-Sumitomo project.