Most people do it everyday. They do this. There is always the mystery lingering of what the effects of it are. There are many answers out there, but they are different. I’m gonna go on a search to find some answers.

For starters, I found a little answer on WikiAnswers. It says:

“It is not normally dangerous to leave a cellphone charger plugged in to the mains unless it has been damaged. However, as the transformer and circuit within the charger normally dissipate small amounts of heat as a result of being connected to the mains supply it is considered to be wasteful of electricity (and thereby damaging to the environment) to leave it plugged in and switched on when it is not required to charge the cellphone.”

This answer obviously applies to the house circuit, but it does apply to a car circuit as well. It seems, however, the main point people seem to be making is all heat related. Like here, on the iLounge forums. RAMd on this forum says this:

“Yes, you can leave the charger plugged into the wall. It probably won’t make much difference in the life span of the charger. Just make sure that it’s not covered somehow so that it gets too warm.”

So, this concludes that, even though the amount of power used by that small charger that isn’t charging, it might mean that the battery will dissipate very little heat, but it will still release some heat, and even the smallest amount of heat can start a fire. It’s obviously best that you don’t leave the charger last night.