Second Life: Used Electric Car Batteries Might Go to the Grid

In math, multiplying two negatives equals a positive. Sometimes the same can be said for sustainability. For all of the benefits electric cars provide to the environment, disposing of their lithium-ion batteries is one of the drawbacks. Separately, it’s also no secret that the nation’s power grids are inefficient and in need of emergency power sources at times of maximum demand.

Now General Motors, maker of the Chevrolet Volt and Zurich-based ABB Group, an international provider of electrical power grid systems, are collaborating to find “creative and cost-effective methods to improve the efficiency of the country’s electrical grid” by using those LI batteries. The idea is to take the old cells, which will likely outlast the cars in which they are installed, and charge them with energy generated by solar and wind power systems. That energy would then be available to use with the electrical grid to meet power demands at peak times.

When GM introduces the Volt later this year, it is expected to offer an eight-year, 100,000 mile warranty on its LI battery. Nissan, which plans to introduce the battery-powered Leaf this year, is expected to do the same. But experts believe the batteries could last well beyond those estimates. Micky Bly, General Motors’ executive director of Electrical Systems, Hybrids, Electric Vehicles and Batteries, estimates that a 16 kilowatt-hour battery will still have as much as 70 percent of its life left by the time the car has exceeded its usefulness.

Those abandoned batteries could turn out to be a significant source of back-up power because production is ramping up. Proponents of hybrid vehicles and battery-electric cars estimate they’ll make up as much as 20 percent of the global automotive market by 2020. Rather than dump into landfills the millions of batteries made for those cars, GM and ABB are considering alternatives.

Using the batteries to store renewable energy generated by solar and wind sources, which utilities would be able to use to meet demand during high-peak power periods, is something ABB would welcome. Regulators are pushing the company to use more renewable power sources, but ABB and the utilities it works with need a reliable alternative before they can move dramatically away from gas, nuclear energy or coal. Still they see collections of LI batteries, much like wind farms or solar panel farms playing a larger role.

“Future smart grids will incorporate a larger proportion of renewable energy sources and will need to supply a vast e-mobility infrastructure, both of which require a wide range of energy storage solutions,” said Bazmi Husain, head of ABB’s smart grids initiative. “We are excited to explore the possibility of employing electric car batteries in a second use that could help build needed storage capacity and provide far-reaching economic and environmental benefits.”

One response

  1. I would expect to see a strong secondary market (outside of the utilities) for these packs at first. As we are now seeing with some of the older NiMH hybrids, the packs are disassembled and individual strings are tested and the good ones used for replacements; so first we’ll see a salvaged parts market. The next major demand would be mainly from existing and new stand-alone grid-isolated systems and backup systems which would incorporate these packs before utilities get into the game. There are a lot of lead-acid batteries that are regularly replaced that could be replaced with these.

    Unless the auto makers introduce a return program for de-manufacturing vehicles where they can control the recycling stream and offer utilities a bulk price, it’s hard to imagine that utilities would be willing to pay more per pack than smaller scale users on an open market. Given the variability of the packs as they are retired after different cycling, uniformity of the packs will be a major hurdle for large scale deployment. From an engineering standpoint, it will be much easier to utilize these packs to replace small relatively short-lived and high maintenance lead-acid UPS and backup packs than to try to combine them into a few utility-scale systems. Small scale users can deal with this issue more inexpensively and easily – needing only one pack or a few well matched ones instead of trying to combine hundreds or thousands.

    In short, in my opinion, I don’t see this as being an answer for utilities for quite some time. There are too many “better” (from an economic standpoint) uses that will need to be satisfied before the price is right for utilities adding several years before implementation. It seems like a good idea in the long run, but I don’t see these first electric cars (Volt, LEAF, etc.) being part of this type of program. Wider adoption of EVs will need to happen first.

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