Power bank that stops charging

[_Sebaz]

I want to make a power bank that stops charging when the phone is full. Is there a simple circuit that can detect the charge of a phone?

[You_are_a_cunt]

Unless the phone is off, it'll never stop charging.

Even in standby the battery is discharging.

[Aelita Sophie]

Actually, most decent powerbanks stops charging when a certain minimum load isnt met. If your phone is done charging, it should stop charging after a few minutes. As long your phone usage isn't high and the battery is in good condition. iPhones simply stop taking current at all once they hit 100%, and they will only accept current if the charge of the battery gets lower then 95% after that. Not sure how this is with other phones in general though. But it seems like a semi-software/hardware feature.

[mariushm]

Most phones have a battery management/charging IC that will stop charging the battery once it reaches 100% (well, the phone may say 100% but the IC inside the phone may still continue to trickle charge the battery at very low current for an hour or so after it shows 100% but that's normal charging process and doesn't hurt the battery in your phone)

 

Some battery banks monitor the current pulled from them and if it's too low (let's say less than 5mA), they'll stop providing power (they'll constantly check maybe once a second or something like that and keep turning off if the current pulled is too low).

With these battery banks, when the battery reaches that threshold where the charger/management ic inside the switch may switch to "trickle charge" mode, it could be that this trickle charge current is so low that it's below that level and the battery bank will turn itself off.

Again, it won't hurt your phone if this trickle charge isn't performed, but also wouldn't help .. it doesn't make a difference.