Battery energy-storage capacity diminishes over time, to the point where packs are no longer suitable for use in cars.
But after their automotive service lives are finished, battery packs often still have enough usable capacity for other applications.
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Like, for example, powering a cluster of buildings in a remote part of Yellowstone National Park.
Used Toyota Camry Hybrid battery packs will now store energy generated from solar panels at the Lamar Buffalo Ranch field campus within the park.
The system includes 208 Camry Hybrid nickel-metal-hydride battery packs recovered from Toyota dealers, providing a total of 85 kilowatt-hours of storage capacity.
Used Toyota Camry Hybrid battery packs installed at Lamar Buffalo Ranch, Yellowstone National ParkEnlarge Photo
The packs were augmented with battery-management systems from Indy Power Systems, re-wired in parallel, and arranged into arrays of 52 packs each.
The solar array used to power Lamar Buffalo Ranch's five buildings generates enough electricity annually to power six average U.S. households, Toyota says.
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Adding onsite battery packs makes the most of solar power by storing energy for when sunlight isn't available--making for a more dependable source of power.
Micro-hydro turbines--which capture energy from a nearby stream--will be added to the site in 2016 as well.
It's also possible to recycle batteries--Toyota has its own recycling program--but repurposing them can have added benefits.
2009 Toyota Camry HybridEnlarge Photo
And while the nickel-metal-hydride packs used in Toyota hybrids contain precious metals, the higher-capacity lithium-ion cells in electric cars are made from relatively cheap stuff.
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So there's less money to be made recycling those, increasing the attractiveness of secondary use.
Either way, there shouldn't be any reason to worry about battery packs ending up in landfills after their automotive service is finished.
Whether they're broken down for recycling or repurposed for new uses, they can live on.