Battery Backup Guide

Raisen asked:


I am looking for some kind of rechargable battery that can be plugged into the iPhone to work as an extra battery because I use it extensively and usually have to charge three times a day.

I have an iPhone 3GS

nikhilkerala asked:


I have a remote controlled car that runs on a rechargable sealed 12v battery. But the car has no speed controls. Only forward, reverse, left and right… The car’s standard speed is too high to be controlled on the remote without bumping into walls and objects. But I noticed a slow down on the car when battery charge reaches like 25%. So I tried to drop some voltage by connecting five 1N4001 general purpose silicon diodes in series to the battery…. The speed was now perfect… But after running the car for like 5 minutes, I opened the battery enclosure to see the plastic body of the car in contact with the diode, started melting due to the high temperature produced due to the high current thru the diodes…..

Is there any other good way to drop a 3v from a approx. 1A 12v battery such that no heat is produced….. ?

Theoritically, when I run the car slower, I should get more hours of battery backup….. But not if all those energy is wasted as heat……

Pls Help….

JizZ E. Jizzy asked:


don’t steal my idea, this is considered “in writing” and I said it first.

I think it would be a very useful addition to homes since most of our electronics require DC power. Just about anything you plug into the wall that has a big black box on the cord is taking the 120V AC voltage from the electric companies and turning it into a much lower 6V to 24V DC power. This could be avoided by having a self contained power source in the basement with a gas powered generator.
Think about it. with our homes battery powered, a ‘power-out’ could shut down your neighborhood and you still have your DC powered electronics. your laptops, cable modems, routers, etc will still be working.
My home uses a cable modem that also takes care of my phone line. in a blackout, I loose my telephone. But not if it has a battery backup. They already make battery backups but why not have it central to the house. and with gasolene recharging it you have that power in case of emergencies.