This question applies equally to both non-rechargeable batteries and rechargeable batteries.

I want to know if I managed to fully recharge my rechargeable batteries (mine are primitive), and how much battery life is remaining in my non-rechargeable ones.

  • \$\begingroup\$ Here is how to do it for LiPo's electronics.stackexchange.com/questions/2601/… \$\endgroup\$
    – Kellenjb
    Jan 24, 2012 at 19:04
  • 1
    \$\begingroup\$ @inquilineKea, can you specify a chemistry, this is a very chemistry dependent process. \$\endgroup\$
    – Kortuk
    Jan 24, 2012 at 19:08
  • \$\begingroup\$ @Kortuk - The OP seems to want to do this for all chemistries, which will be very difficult. \$\endgroup\$ Jan 24, 2012 at 19:09
  • \$\begingroup\$ @KevinVermeer, I am specifying that it seems to be too broad to reasonably answer. Asking if the user can specify a chemistry to receive answers for. \$\endgroup\$
    – Kortuk
    Jan 24, 2012 at 19:14
  • \$\begingroup\$ Okay - changed to alkaline battery. \$\endgroup\$ Jan 24, 2012 at 19:26

1 Answer 1


If we talk about small AA, AAA and coin batteries (both 1.5V and lithium 3V), then the simplest estimation can be made using a voltmeter. The voltage goes down (declines) over time and usage.

Note that each particular device needs a different minimum voltage to operate normally, so for example a battery from one device which seems dead can be put somewhere else and operate normally (at least for a little while). For example my digital weigh is quite demanding - it ceases operation already when the voltage drops to 2.88 V, and those lithium batteries are still well usable in bicycle computer or somewhere else.

Update: Note that alkaline batteries have got some kind of self-healing effect. When they are not used for a while, their voltage goes a bit higher. This can mislead your voltage measurements. So you should put them back to some load for a few seconds and then you can see their real health. Also note that totally dead batteries don't need this; they show voltage near to zero even without any load.

  • 2
    \$\begingroup\$ There is some value to measuring under load. I have very little experience with alkaline batteries. This does not work for lithium batteries though, they need to have a load applied otherwise their discharge curve is almost flat minus the very last bit of death. \$\endgroup\$
    – Kortuk
    Jan 24, 2012 at 19:41
  • \$\begingroup\$ Good point, Kortuk. +1 \$\endgroup\$
    – Al Kepp
    Jan 25, 2012 at 10:32

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

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