Reposted from Marin Voice, Marin Independent Journal, 9/1/2025.
This is the time of year when people like to ask what you did on summer vacation. When I tell them I attended a three-day battery recycling conference in Reno, they look puzzled.
Indeed, the conference was an unusual choice for someone who nearly flunked freshman chemistry. But time at the NAATBatt Lithium Battery Recycling and Lifecycle Management Workshop was well spent and there is good news for electric vehicle drivers and environmentalists in Marin and elsewhere.
There was optimism among the more than 200 attendees. There is a second-life for the batteries in our cars. Circular manufacturing means that EV batteries are never wasted and this sustainable process reduces the need for new materials. The key is not tossing out things that are valuable, namely old batteries.
For starters, it was a shock to realize how many lithium batteries are found in our households. There are batteries in the TV remote control, garage door opener, kids’ toys, power tools, vapes, electric toothbrushes and, of course, mobile phones. Tragically, most of these smaller batteries end up at the dump and only 15% of old smartphones get recycled. One speaker said that lithium batteries ignite at least one fire a week in New York City trash collections.
The risk of fire is greater for lithium power packs in EVs but so are the safety precautions. When they are removed from a car, these batteries retain about 80% of their energy. If you hook up this battery to your house, that’s enough energy to keep everything going (except the air conditioner) for about three weeks. Those used EV batteries have a lot of “work” left in them.
With this potential in mind, the business of repurposing EV batteries for stationary storage is getting started. At the conference, we visited the 300-acre site of Redwood Materials, the country’s best-known recycler of EV batteries. In their second-life, each repurposed car battery sits atop a cinder-block base, carefully separated from its neighbors to reduce the fire risk.
During the daytime, these retired batteries collect energy from sunlight, and refill a much larger storage battery. The kicker is that next door there is a brand new Google data center that has intensive needs to fuel AI searches. Redwood Materials is testing the use of these second-life batteries to power data centers.
We also saw a more traditional way to repurpose EV car batteries. It gave me a deeper appreciation for the tariff wars. The 12-volt battery in cars (the stubby one you buy at the auto parts store) is always recycled for its lead content. The materials in an electric car battery are far more valuable, and they also get smelted down, this time into a powdery mass.
The kicker is that 90% of this lode star, which is appropriately called “black mass” gets sold to China where circular manufacturing is used to build brand-new cars. China makes nearly 60% of the world’s passenger electric vehicles while automakers in the U.S. struggle with the costs and supply chain for EVs. A good place to start would be to keep more of our black mass in this country, while reducing the need to mine for cobalt and other minerals overseas.
On the trip home I reflected that my summer vacation was time well spent. I also started thinking about a program called “Bye Bye Battery,” which my middle son and I had started at his high school to collect old batteries.
In retrospect, “Bye Bye Battery” was not well named. Old batteries should get recycled over and over for their minerals or get repurposed into “next-gen” power walls. Batteries are simply too They are too valuable to throw away.
And that leads to the bigger question: We love our smartphones and their longer-life batteries. Isn’t it time to love electric vehicles and the second-life they can bring?