Second-life car batteries can bring electricity to millions

Published on Tuesday, 22 November 2016

Published by Sohail Hasnie on Tuesday, 22 November 2016

Lithium-ion batteries on a Tesla electric car chassis.
Lithium-ion batteries on a Tesla electric car chassis.

Did you know 10,000 old car batteries from the developed world could power 150,000 homes in the developing world?

One person’s trash is another person’s treasure. We all know that. But this concept may allow us to link two markets: the large number of electric vehicles in developed countries, and the off-grid solar market in the developing countries. For example, a set of old car batteries is a liability in Sydney, Australia, but in Afghanistan or Pakistan it can be a treasure to jump-start an off-grid solar revolution.

Last month, I had the opportunity to discuss off-grid electrification options with the CEOs of a  public power utility in Afghanistan and a private utility in Pakistan. Both were keen to bring second-life batteries to their markets.

I found two recent publications very relevant to our discussions.

An article in Green Tech Media notes that cars require very high performance from their batteries, so batteries are retired when the capacity declines to 70-80%, although the batteries can still handle a lot of charge and discharge, and can be useful for stationary storage. If used batteries can be sold as a cheaper alternative to new storage, they could help rooftop solar generation, or reduce their peak demand. A standard battery design that incorporates storage on second-life batteries would make electric cars cheaper for second-life adapters, so these vehicles would become accessible to low-income customers. This would in turn create a market for used batteries, like the used car market.

Bloomberg reports that about 95,000 MWh of second-life lithium-ion batteries will be available from cars by 2025, and 26,000 MWh will be used as stationary systems (currently only 100 MWh are available as second-life). Used batteries in stationary storage cost half as much as a brand-new one. Developing a secondary market for second-life batteries (70% of original capacity) will reduce the cost of ownership, and delay the need for end-of-use recycling.

Let’s tackle the bottom line. The two cells (2x500 Wh) from the 48 cells (24 kWh) that form the battery pack of a Nissan Leaf electric car, for example, can power an off-grid solar kit for another 3-5 years. The new batteries were about $350/kWh, but applying the 50% price reduction the two cells could more than $150/kWh.

A $100-150/kWh price for lithium-ion batteries for off-grid solar systems will be a big disrupter in developing Asia. According to my rough calculations, we would only need the old batteries from 10,000 cars to bring electricity to 150,000 off-grid households.

Please feel free to share your insights to design a project that may enable a market for 160 MWh off-grid installations of second-life batteries.