Originally posted by sonhouse
Maybe they weigh the same but they don't take up internal volume so there would be more space to use by the driver. It remains to be seen how much energy such battery paint could store per square meter or per Kg. Probably less power density than regular Li Ion cells would be my guess.
Yeah but these batteries are not structural, they add weight not strength.
On the outside they are vulnerable to damage, and decrease stability by raising the centre
of gravity compared to batteries placed low down on the chassis.
If you have a fender bender or accidentally scrape against a gate post or tree (when you go
camping) then rather than just scratching the paint/denting the bodywork you have now
damaged the batteries powering your car and are possibly leaking toxic/corrosive battery
fluid to boot.
Also when the batteries run down you have to replace the body panels rather than just take
out the battery pack and replace it.
And when you dispose of the car at the end of it's life you can't just take the batteries out for
safe disposal before crushing, you now have to somehow scrape the batteries off all the
bodywork before disposal.
In an accident (even a minor one) you could potentially get battery acid/alkali sprayed everywhere.
And given that a typical battery powered car currently has hundreds of kilos worth of Li Ion batteries
in it and these batteries are likely to be lower power density you are only likely to be able to get
a small fraction of the cars power storage capacity as battery paint on the outside and so will still
need a big battery block on the inside as well.
I am sure there are potential uses for these paint on batteries, I just don't see them as being practical