1
$\begingroup$

I know salt water batteries are less efficient than lithium-ion, but water is safer, can be found anywhere, is cheap and 100% ecological. Even if it doesn't last long, you can refill anywhere. Why can't salt water batteries be used to power electric cars?

$\endgroup$
2
  • $\begingroup$ My guess is that energy density is too low. $\endgroup$ – my2cts Nov 10 '19 at 10:45
  • $\begingroup$ Is salt water lighter than lithium? $\endgroup$ – Steeven Nov 10 '19 at 12:41
4
$\begingroup$

Water has one major setback: It is chemically stable only up to a voltage of 1.22 volts. This means that a water cell supplies three times less voltage than a customary lithium ion cell with 3.7 volts, which makes it poorly suited for applications in electric cars. However, water-based batteries, could be interesting for stationary electricity storage applications.

Secondly it is not true that water is lighter; Lithium is the least dense of all the metals, it has a density nearly half that of water $0.534 g/cm^3$.

$\endgroup$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.