S60 Open to new features

From what I know, trickle charging continues all the time you are plugged in. May be some electronics junkie wants to correct me.

I agree with your solution, however if the charger detects battery at not 100% will it start to charge again? That could be a problem as once cut-off, dropping below 100 could happen very fast. Unless the power switch is not switched off and on again charging should not start.

I don't want to be woken up at 3am by my phone just to be informed that charging is complete.

Boom

The phone DOES cut off energy flow into the battery when it's charged. Otherwise the battery would explode. The lithium battery industry calls this "venting with flame", and it's the reason charge control circuits have gotten so much more complex in the last decade. Nickel-cadmium batteries didn't really care if you left them on a charger forever, but lithium-ion chemistry is totally different, and they'll happily blow up if you don't cut off the charge at the right time.

Of course, while the phone sits in standby while plugged into the charger, it does drain a bit of power from the battery, so periodically the circuit switches back on to replenish what was used. This is probably exactly the behavior you want.

However, once you've unplugged your phone, the charger *continues* to draw a little current from the wall socket. This is referred to as a "phantom load" in energy conservation circles, and it's the problem Nokia et al are trying to address. Ever notice that the charging brick keeps itself warm even when there's no phone plugged into it? That represents a watt or two of absolutely useless electrical load. Unplug your wall-warts when there's nothing connected downstream!

Look up "phantom load" for more information. Anything with a remote control keeps part of itself "awake" even when it's turned off, so it's able to respond to the remote turn-on signal. Together, your sleeping TV, stereo, microwave clock, cellphone charger, toothbrush charger, garage door opener receiver, and dozens of other phantom loads make up a surprisingly significant fraction of your home's energy use, because they run 24/7.

By reminding users to unplug the charger from the wall when not in use, this "initiative" might raise awareness about the phantom load problem in general. It'd be nice to be able to turn the TV all the way off (but mine requires 5 minutes to re-learn all the channels after a power interruption -- couldn't that be stored in flash?) but that capability won't exist until consumers demand it.

Thank you about very informative reply.

It's easy to understand that equipments with infra red, like TVs, need energy in standby mode. A mobile phone charger should be possible to design so that it's really off, when phone is not connected to it. I'm quite sure that electric kettle doesn't consume power once water has boiled and when it has switched power off automatically. Ideally charger shouldn't need "manual activation" (like kettle) when phone is connected. There must be solution for this.