> Is there some reason why solid state batteries seem to be being deployed in cars sooner than in phones?
Not quite energy density, but the energy density, cost, complexity when combined with the discharge profile generates a very "interesting" phase space.
There's a few promising technologies which have very, very good efficiencies but only like very slow predictable discharge cycles. These are excellent for say building giant GW batteries in the desert, but not so great for even car batteries.
Phones and tech have bursty power needs based on use, the cost of taking other tech down to the size of a phone is extremely high (especially if you're first to market unless you know you will sell millions of units). Not to mention the reliability of batteries typically decreasing as the size drops.
Cars tend to be in the middle with their discharge profiles being relatively smooth compared to say a laptop, but yes you still have economies of scale, complexity, reliability and supply chain and patents to contend with ;)
> isn't a normal cell in an EV battery is like a AA size?
No. Some companies use tons of cylindrical cells that are larger AAs (like 18mmx65mm, 21mmx80mm, or 46mmx80mm). But even then at 46mm in diameter it's a good bit bigger than a AA.
But lots of manufacturers use prismatic or pouch like batteries. They're large and rectangular. Like these batteries on this BYD, they're called "blades". Most other major manufacturers use prismatic cells.
Not quite energy density, but the energy density, cost, complexity when combined with the discharge profile generates a very "interesting" phase space.
There's a few promising technologies which have very, very good efficiencies but only like very slow predictable discharge cycles. These are excellent for say building giant GW batteries in the desert, but not so great for even car batteries.
Phones and tech have bursty power needs based on use, the cost of taking other tech down to the size of a phone is extremely high (especially if you're first to market unless you know you will sell millions of units). Not to mention the reliability of batteries typically decreasing as the size drops.
Cars tend to be in the middle with their discharge profiles being relatively smooth compared to say a laptop, but yes you still have economies of scale, complexity, reliability and supply chain and patents to contend with ;)