Lots of them are bought for their patents/designs then shelved, so manufacturers can continue to make profits selling batteries year on year.
Think about it, a battery that lasts 10+ years with little to no degradation isn't good for business.
How else would Apple and other smartphone makers convince you to buy a new $1-1500 phone every year?
So fascinating how we've had working solid state batteries for more than a decade yet not a single mass produced one, despite so many continuous advancements and milestones in density and BOM.
Most of the research these days is funnelled into making existing tech level batteries cheaper, such as lithium iron phosphate, rather than making better batteries that have more energy density and longevity. It's not hard to see why.
The next thing we'll be sold is the "circular economy" where we pretend we don't know how to make things that last decades anymore, and that it's some kind of environmental genius to recycle and remanufacture things using "clean" energy every 3-5 years.
Cynical moment of the day has passed now, I'm off to gym then campus.
I'm just pissed I'm still using my S10+ Ceramic 512 GB Snapdragon, because I vowed not to replace it until solid state batteries were put in Galaxy phones. Not that it's a bad phone, battery lasts two days since I replaced it and ADB'd away the bloat.