'Second-life' EV batteries could drive low-cost storage sector, says BNEF report


A report by Bloomberg New Energy Finance (BNEF) on second-life uses for electric vehicle (EV) batteries in stationary storage applications has forecast immense cost-cutting potential for the technology.

Currently, there has been no consensus on how best to dispose or re-energize used car batteries in EVs. However, BNEF’s senior analyst Claire Curry has compiled first data that suggests how used EV batteries can enjoy a ‘second life’ in stationary storage systems – and bring down costs sharply in the process.

By 2025, the BNEF report forecasts, there will be 29 GWh of used EV batteries coming out of cars. This number far exceeds the current stationary storage market, and it is this exponential growth that will serve to boost lower cost batteries.

Of that 29 GWh figure, around one-third (10 GWh) will get a second life as stationary storage. New storage systems can cost as much as $1,000/kWh, but even by 2018, the cost of repurposing a used EV battery could be as little as $49/kWh. Add in the $400/kWh cost to convert to stationary and the industry could be looking at masses of affordable batteries entering the market at a price point below $500/kWh.

While Tesla has stated that it will not be following a repurposing model for its EV batteries, other large players in the EV space have already put second-life stationary storage projects into place, including Nissan and Mercedes-Benz.

In Germany, Mercedes-Benz is looking at using its repurposed EV lithium-ion batteries in stationary storage projects designed to provide Primary Control Reserve. The company is confident that a typical battery that is no longer of use for an EV could have at least 10 more years of operability in stationary systems.

The issue of repurposing EV batteries for large-scale storage is explored at length in the forthcoming September issue of pv magazine, with Mercedes-Benz’s projects featured as a case study of this growing market.