The problem with the "used EV battery market" is that the damn EV batteries are lasting longer than anyone expected.

So there are no batteries to develop an actual industry around, most are just one-offs.

Nissan created a PowerWall-like division for the secondary market. That division made a commitment to only ever use secondary use batteries. (Unlike PowerWall which has yet to build one from secondary use batteries. They use fresh manufactured batteries.)

Nissan's early Leafs have the reputation as the cars with the most degraded batteries coming back into the used car market, and some of Nissan's earliest Leafs were sold under a "battery leasing model" where the car was sold but the battery was still under lease from Nissan giving Nissan incentive to replace the battery if it dropped below certain warranty thresholds. Yet despite the "notorious degraded Leaf battery" and decades of the Leafs existence and batteries that possibly owners could call in lease terms for replacements out there, statistics show that the vast majority of Leaf batteries are still in primary usage (people are still driving those "degraded" batteries, there is a used car market for them) and Nissan claims they've yet to see enough batteries enter the secondary use market to build even a single one of their PowerWall-equivalent products.

I wonder how many households realized they didn't need all that range after all since they have a second ICE car anyways. So the Leaf pretty much stays in a 30 miles radius of the house.

From my own anecdotal evidence I think a lot of people absolutely underestimate the impact of home charging (even at "trickle" Level 1 in the US) versus "range anxiety". In the nearly a decade I've had my PHEV, two of my three daily commutes I could and did entirely every day on the range I can Level 1 trickle charge entirely at home overnight.

People massively over-estimate the range they think they need because they don't take things like home charging into account.

Exactly this.

From a regular European 230V outlet you can get 100km of range every night easily. Even more if you don't work 16 hour days.

The average commute around here is a bit over 50km a day, both ways combined.

> Who is taking the batteries and putting them into grids?

Right now, hobbyists. There's high demand for used Leaf modules - so much so that they're getting fairly difficult to find these days. Golf cart conversions are popular and easy.

Which doesn’t sound like much of a plan once the entire worlds cars contain giant batteries.

There isn't enough supply to support commercial versions yet. When there is, expect budget powerwalls. Used batteries would be perfect since home backup rarely sees full discharge.

This is a problem the market is perfectly capable of solving. Batteries are valuable.

If there was nobody left to buy used batteries for storage, then there would still be plenty of recyclers looking to buy them.

And the people who bought a 25% worn battery for storage would be looking for another new one at some point, at which time they will sell the old one off for recycling.

So a time and resource intensive process for recycling giant heavy objects that can explode will be effective in every country of the planet at the scale of every car?

I’m not saying it couldn’t be true, but I’m quite skeptical…

There's already Li-Cycle and Redwood Materials. No obvious reason why they couldn't scale.

Reuse like this can extend the useful life of the battery, but not forever. So sooner or later they will need to be recycled anyhow. Accordingly, I don’t think we need to worry about the market for used batteries drying up.