If the cost of new volts were to suddenly go up, that might cause the value of my car to go up as well. Since fewer people will be willing/able to cough up the money for a new one, used ones start to become more attractive. There's no guarantee of course. EVs are still seen as a risky purchase because of the expense of replacing the battery. The number of people willing to take a gamble on a used one may be finite.
True, it *might* go up a little bit, but I doubt by very much - You are very
correct that used EV's are still considered a big risk by the general public and that really
hurts their used value. They can be a real bargain used if you understand what you're buying
Case in point - In 2012 we paid the $30K sticker price for our first Mitsubishi EV (less the $7500 credit) and then 2 years later we bought a second one used when it came off lease. The second one had a $34K sticker when new (it had Nav, Bluetooth, Hard drive for the audio and DCQC which the first one doesn't have) and we only paid $8,700 for that one with 3,900 miles on it!
- Looked, smelled and drove like a brand new car . . . . and the tax credits were still there - If they had been cancelled when we bought that second one, it might have bumped up the price by a few hundred, but I seriously doubt it would have raised it by very much. If we're talking about a 3 or 4 year old Volt with 75K on the clock, I seriously doubt it would matter much at all
Anything used is worth what someone else is willing to pay for it and used EVs (especially those with significant miles) are already well below what a 'regular' car with the same mileage would sell for