They're still working on this. I've more or less been holding my breath on the battery tech.
I want to see, either easily recycled materials that are common (sodium cells seem to fit here), or batteries that last the useful life of the vehicle and beyond (solid state batteries are a good example here). I don't really care which.
Cheap sodium based batteries, with adequate recycling technology would be a fine solution. Alternatively, even fairly "expensive" (in terms of rare metals) solid state batteries, would also be fine, since a single set of batteries may survive over several vehicles, depending on what solid state batteries can do when they finally hit the mass market.
I just don't want to have to replace the battery at nearly the cost of a whole ass new EV, well short of the useful life of the rest of the vehicle. Either the battery cost and environmental impact comes down, or we remove the need to replace the batteries with a version that lasts as long or longer than the rest of the vehicle.
I like EVs. I want an EV. I don't want to buy the current EVs on the market.
Also, if any vehicle designers are reading this, can we cut the shit where anything hybrid or EV looks ridiculous? IMO, a big reason why Tesla was so successful, is that they made it into a car. The model S, though unique in design, isn't a significant departure from pretty much every other sedan, in terms of design. Compare with something like the Prius, which is generally only a funny looking hatchback, or the Volt.... Which also looks pretty dumb IMO. Just give me a regular car.
... Okay, the Prius and Volt probably aren't the best examples. I'll put a better one here.... The BMW i3. Just.... What the hell.