A new life for old batteries

Is the future of used electric car batteries in grid energy storage systems like the Second Life Batteries Alliance project from BMW, Bosch and Vattenfall in Germany?
Is the future of used electric car batteries in grid energy storage systems like the Second Life Batteries Alliance project from BMW, Bosch and Vattenfall in Germany? Photo credit: BMW AG, München, Deutschland
Is the future of used electric car batteries in grid energy storage systems like the Second Life Batteries Alliance project from BMW, Bosch and Vattenfall in Germany?

Is the future of used electric car batteries in grid energy storage systems like the Second Life Batteries Alliance project from BMW, Bosch and Vattenfall in Germany? Photo credit: BMW AG, München, Deutschland

A tie-up between BMW, Bosch and Vattenfall in Germany could help speed up halting moves to develop low-cost energy storage reserves from old car batteries.The three companies last month launched the Second Life Batteries Alliance “to form a large-scale energy storage system in Hamburg,” according to Bosch.

BMW will be supplying more than 100 second-hand lithium-ion batteries from its ActiveE and i3 electric vehicles, while Vattenfall has agreed to operate the Hamburg storage system for 10 years as part of an existing ‘virtual power plant’.

Bosch, which has developed integrated storage systems for the communities of Braderup and Kelsterbach in Germany, will be in charge of integrating the batteries and managing the setup.

It has developed a management algorithm to extend the service life and performance of the batteries. “Lithium-ion batteries still have high storage capacity at the end of their life cycle in electric vehicles,” said Bosch in a press release.

“As a result, they are still very valuable and can be used extremely efficiently as stationary buffer storage for many years to come.”

‘Numerous new insights’

Bosch added: “The project allows the three partners to gain numerous new insights into potential areas of application for such batteries, their aging behaviour and their storage capacity.”

When completed later this year, the facility should have an output of 2MW and an installed capacity of 2MWh. It is far from the first attempt at using old car batteries for grid-scale energy storage, however.

Back in 2012, General Motors and ABB collaborated to use sets of five second-hand Chevy Volt batteries as the basis for modular micro-grid energy storage systems delivering 25kW and 50kWh.

And as previously reported in Energy Storage Report, Duke Energy has evaluated FIAMM sodium-nickel bus batteries for grid applications such as frequency control.

Duke’s senior vice president and chief technology officer, David Mohler, said using second-hand batteries could cut the capital costs of grid-scale battery deployment by up to 70%.

Critical and inexpensive

Last September, the idea of using second-hand vehicle batteries was mooted as one of the answers to California’s grid-scale energy storage requirements in a report, Reuse and Repower, linked to two of the most prestigious law schools on the US West Coast.

“Used electric vehicle batteries could be a critical and inexpensive part of the solution,” wrote author Ethan Elkind of the Climate Change and Business Program at Berkeley University of California and the University of California, Los Angeles, Schools of Law.

“Assuming 50% of the battery packs on the road in 2014 can be re-purposed, with 75% of their original capacity, these second-life batteries could store and dispatch up to 850MWh of electricity.

“The aggregated capacity is equal to 425MW worth of power,” he added, “almost one third of the energy storage that utilities are required to procure by 2020 under a recent California mandate.”

Besides cutting energy storage costs, Elkind and co-authors from the Emmett Institute on Climate Change and the Environment Berkeley School of Law’s Center for Law, Energy & the Environment said reusing batteries could make electric vehicles cheaper.

Preliminary studies on resale value

“Preliminary studies indicate, for example, that a used 24kWh Nissan Leaf battery could net the vehicle owner up to USD$2,400 in resale value, while a Tesla Model S owner could sell the 85kWh battery pack for up to $8,500,” said the report.

In effect, this could lead to a situation where grid-scale energy storage and electric vehicle markets collaborate in battery cost reduction by giving batteries longer life spans and application ranges.

To achieve this, however, Elkind’s report points out that a number of barriers need to be overcome. Among these are automaker involvement in the second-hand market and improved data on battery life performance in first and second-life applications.

Although it is far from the Californian market, the Second Life Batteries Alliance at least addresses both of these issues.

What remains to be seen is whether the ‘Alliance’ can get beyond three partners with a single project and become a wider driving force for the study and adoption of second-hand car battery applications in energy storage.

Written by Jason Deign

  • Find out more about the California market in the US Energy Storage Technology Outlook, free from Energy Storage Update.

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