Will an unplugged-from-the-wall battery charger drain/harm my cell phone battery?

Here’s the deal. I’ve got an old cell phone that works fine for my needs. Apparently there is no circuitry in the phone or charger that prevents the charger from overcharging the battery, thereby reducing its lifespan. I’ve fried one battery already, so I know this.

I’ve been very good with the new battery, being sure never to overcharge it. But that means watching the clock or setting a cooking timer, which is a big bother. I want to automate the process.

Here’s my plan. I bought an electrical timer-switch. I’ll plug the timer-switch into the wall, and plug the charger into the timer-switch. I’ll set the timer-switch to turn on the charger for about 75 minutes (the time my battery needs to charge) in the middle of the night when I’m asleep. Each night, before I go to bed, I’ll plug my drained phone into the charger; it will get zapped – but not overzapped – while I sleep, and it should be ready for action when I get up.

The only possible flaw in the plan I can think of is letting the fully-charged phone stay attached to the non-charging charger after the charging session is over. The two devices may stay hooked up like that for several hours until I wake up and disconnect them. Will this arrangement drain (or otherwise harm) the battery or phone?

Thanks all, in advance.

Gee, this thread is sinking faster than my cell phone in the East River! I’d have thought that with all the electrical brainiacs we have on this board I’d at least get a few bites.

Maybe this bump will help…

I would say that it’s a pretty poor design if a charger also doubles as a load on the phone, but it’s already shown to be a poor design since it allows overchanrging & ruins your battery. Are you sure the charger isn’t defective? As long as the charger’s output voltage isn’t greater than what the battery is rated to hold, charging current should stop once the battery reaches a full charge.

The best way to find out if the charger will drain the battery is leave it connected to the phone for a day or so and see if the battery loses its charge any faster than what you consider to be normal.