Effect of powered off on battery

Because of the chemical reactions, all batteries drain slowly while offline as well.

Can you be a bit more specific?

Is what I described typical or would you expect it to take years to reach that point?

Can you be a bit more specific?

Is what I described typical or would you expect it to take years to reach that point?

Judge yourself

https://en.wikipedia.org/wiki/Self-discharge

http//batteryuniversity.com/learn/article/elevating_self_discharge

jaclaz

I had an iPad charged to 100%. Powered it off and came back to it after a couple of weeks and it was still 100%. Powered it off and came to it after a couple of months and the battery was at 49%! Is this right or am I looking at a glitch?

Well, unless the battery meter has been properly tested, you may not really know if its zero point is at battery 0 charge (it might be at battery -20 charge), nor do you know if the output curve it produces is linear. Might be linear in some range, say 10% to 80% of battery charge, but slope off outside that range.

The battery manufacturer should be able to provide more info about how the battery behaves over time – I'd expect them to have product specifications with that kind of information. And then you'll have to hunt for the battery meter used in an iPad to know how well it measures battery charge.

Wasn't there an issue fairly recently about some Apple battery meters not updating as they should, showing more charge than actually was present? I think it was for iPhones, though.

I wouldn't trust anything but a proper battery meter.

The self-discharge time is in direct relation with the quality of your battery cells, but you should never trust the values read by sensors, since any degradation of the batteries are unpredictable at some point.