Quote from: fungus on Mar 13, 2013, 11:40 amPredicting "remaining life" is difficult.OTOH knowing when it's "nearly dead" isn't. Most batteries go down to about 1.1V then drop off very quickly (think "cliff").Indeed - any you need to know the actual chemistry of the battery involved, AA cells might be Zinc/carbon, alkaline,NiMH or even NiCd or NiZn! Unless you know the chemistry you can't know which voltage represents the death-knellof the cell. For NiCd for instance its such a flat curve that in practice you can't tell, fortunately with NiMH you canfairly well. So you probably need to decide on a single type of cell to get a reasonably reliable indication.
Predicting "remaining life" is difficult.OTOH knowing when it's "nearly dead" isn't. Most batteries go down to about 1.1V then drop off very quickly (think "cliff").
So, the 1 ma timer draw = approximately 25 ma in a day.
QuoteSo, the 1 ma timer draw = approximately 25 ma in a day.You mean....25mA hours
Hi guys,I am doing a battery life indicator for a device. A red led will light up when the voltage reaches below a certain limit, which is at least 2 days before the AA battery fully dies.As such, I want to know how to determine the number of days left before a AA battery dies. I have attached the datasheet for a AA battery but it only shows the constant current performance chart. My device draws around 50ma current for about 10seconds, 4 times a day, when a motor rotates. And all along, it draws a current (ard 1ma I think) when it runs a timer.So, how can I determine the voltage when the battery is abt 48hours before "dying"?