Battery recycling is one of MIT Technology Review’s 10 Breakthrough Technologies of 2023. Explore the rest of the list here.

As Tesla’s former chief technology officer, JB Straubel has been a major player in bringing electric vehicles to the world. He’s often credited with inventing key pieces of Tesla’s battery technology and establishing the company’s charging network. After leaving Tesla in 2019, Straubel began a new venture: Redwood Materials, a battery recycling company. 

Redwood has raised over $1 billion in venture funding. It’s building a billion-dollar facility in Nevada and recently announced plans for a second campus outside Charleston, South Carolina. In these plants, Redwood plans to extract valuable metals such as cobalt, lithium, and nickel from used batteries and produce cathodes and anodes for new ones. 

I spoke to Straubel about the role he sees battery recycling playing in the transition to renewable energy, his plans for Redwood, and what’s next. You can read my full piece about battery recycling here.

Our conversation has been edited for clarity and length. (Note: I worked as an intern at Tesla in 2016, while Straubel was still CTO, though we didn’t work directly together.) 

Why did you decide to leave Tesla, and why did you pick battery recycling as your next step? 

Certainly Tesla was an amazing adventure, but as it was succeeding, I think it was becoming more obvious that battery scaling would present the need to get so many more raw materials, components, and batteries themselves. That was this looming bottleneck and challenge for the whole industry, even way back then. And I think it’s even more clear today. 

The idea was pretty unconventional at the time. Even your question kind of hints at it—it’s like, why did you leave this glamorous, exciting high-performance car company to go work on garbage? I think entrepreneurship involves being a little bit contrarian. And I think to really make meaningful innovation, it’s often not very conventional.

Why do you see battery recycling as an important part of the energy transition? 

Increasingly, the solution to some of these sustainability problems is to electrify it and to add a battery to it, which is great, and I spent the majority of my career championing that and helping accelerate that. And if we don’t electrify everything, I think our climate goals are completely sunk. But at the same time, it’s a phenomenal amount of batteries. And I just think we really need to figure out a robust solution at the end of life. 

I think this entire new sustainable economy as we’re envisioning it, with everything electrified, simply can’t work unless you have a closed loop for the raw materials. There aren’t enough new raw materials to keep building and throwing them away; it would fundamentally be impossible. 

Battery recycling is an intuitive solution to those two issues, but tell me more about the technical challenge of pulling it off, and how it would work.

It’s more complicated than I think many people appreciate. There’s just a whole ton of chemistry, chemical engineering, and production engineering that has to happen to make and refine all of the components that go into a battery. It’s not just a sorting or garbage management problem. 

There’s a lot of room for innovation, and these things haven’t been well optimized, or even done at all in some cases. So that’s really the fun stuff as an engineer, where you get to invent and innovate things that haven’t been done two, three, four times already.  

But something that isn’t intuitive is just what a high level of reusability the metals inside of a battery have. All of those materials we put into a battery and into an EV don’t go anywhere. They’re all still there. They don’t get degraded, they don’t get compromised—99% of those metals, or perhaps more, can be reused again and again and again. Literally hundreds, perhaps thousands of times.

I don’t believe we’re appropriately internalizing how bad climate change is going to be.

JB Straubel

There are not going to be a lot of electric vehicles coming off the roads for a long time. How are you thinking about navigating that and facing shortages in your supply of used batteries? 

I really see our position as a sustainable battery materials company. One of our key objectives and goals is to look at the very long term and to make sure we’re architecting the most efficient systems for the long term, where recycled material content is the majority of supply. 

But in the meantime, we’re taking a pragmatic view. We have to blend in a certain amount of virgin material—whatever we can get in the most environmentally friendly way—to augment the ramp-up while we need to transition away from fossil fuels. 

Was that a clear decision to you, to supplement with mined material versus sticking to only using recycled material? 

I’d say it’s a very natural decision to make. Our goal is to help decarbonize batteries and reduce the energy impact and the embedded CO2. And I think it’s better for the world to remove a fossil-fuel vehicle than to say, “Well, we can’t build an electric vehicle because we don’t have enough recycled material.” 

When I visited, I definitely felt a sense of urgency. Do you feel like you’re moving fast enough, and do you feel like this industry is moving fast enough? 

I generally don’t think we’re going fast enough. I don’t think anyone is. You know, I do have this sense of paranoia and urgency and almost—not exactly—panic. That’s not helpful. 

But I guess it really derives from a deep feeling that I don’t believe we’re appropriately internalizing how bad climate change is going to be. So I guess I have this anxiety and fear that it’s going to get a whole lot worse than I think most people are expecting. 

And there’s such inertia to it, so now is our only time to really prepare and react. And the scale of all this is so big that even when we’re running flat out as fast as we can, with all that urgency that you felt and hopefully more, it’ll still take us decades.

Do you feel you can handle any battery chemistry that industry comes up with? What if everybody goes to cheaper chemistries like iron phosphate, or if everybody starts moving to really different technologies, like solid state?

I’m really genuinely pretty agnostic on this. I want to make sure that we are focused on the bigger picture, which is figuring out how we enable a transition to sustainability overall. And therefore, we really are rooting for whatever battery technology ends up having the best performance.

And I think it will be a mix. We’re going to see a bigger diversity of battery chemistries and technologies. 

So when we’re designing this circular system, we need to think about all the different technologies, and they have pros and cons. Some are more challenging in different ways. Obviously, iron phosphate has a lower total commodity metal value, but it’s certainly not zero. There’s a great opportunity to recycle lithium and copper from those. So I think each one has its own set of characteristics that we have to manage.

What do you see as Redwood’s biggest challenge in the next year, and then in the long term?

Over the next year, we’re just in an incredibly rapid growth and deployment phase. We are innovating across a whole bunch of different areas simultaneously. It’s really exciting and fun, but it’s also just quite challenging to manage all of the parallel threads as we’re doing it. It’s like a huge multiplayer game of chess or something. 

In the longer term, it’s increasingly going to be about scale and efficiency of scaling. This is just a huge, huge industry. The physical size of these facilities is massive, the amount of materials is massive, and the capital requirements are really massive as well. So I think over decades into the future, I’d say, where our focus and challenges will be is making sure we’re hyper-efficient about scaling up to terawatt-hour scale, literally.

Correction: this article was updated to correct Redwood's fundraising total.