A New End-of-life Use For Used EV Batteries

There’s a battery startup project in the California desert that even thrift shop Macklemore would be proud of.

What happened: B2U, a large-scale energy storage solution company out of California, recently put into operation a 25 megawatt-hour grid-scale stationary storage system called Sierra. Using 1300 recycled EV batteries to store excess solar-generated electricity, it’s the largest installation of its kind in the world.

• For context, 25 megawatt-hours is roughly the annual electricity consumption of 2 and a half average homes in the US. We’ll be honest, that’s not a lot.

The Sierra system provides a second life for EV batteries at the point they’re no longer useful in transport but before completely empty.

• This particular project will use old Honda and Nissan batteries, but Tesla batteries would work just fine.

The benefit: By installing them just as they are, the system safely optimizes the charging and discharging of each battery in the system with little-to-no repurposing costs. B2U claims this makes an attractive levelized cost of storage for their systems.

Not a moment too soon for EV battery recycling

EVs on the rise: Bloomberg reported yesterday that the all-time total value of electric vehicles sold has crossed $1 trillion. Minor compared to the $2.5 trillion in annual auto sales, but the rate of sales growth here is key.

• Close to 60 percent of that $1 trillion came in over the last 18 months of the roughly 10 years that EVs have been around.

Big picture: We can’t say for sure how much of that increase in sales value is due to *shudders* inflation, but that rise in sales means a growing wave of soon-to-be-retired EV batteries.

The Sierra project’s modest beginning is on the right path towards a circular economy approach where the lifetime use of an EV battery is maximized. Throw in some recycling and we have ourselves a full circle that may soften the mining demand of new critical minerals in the future.