Battery Backup Guide

mtm asked:


I thought that you need a physical contact between the charger and the battery so the electricity actually arrives inside the battery.
Now my new electrical toothbrush seems to work differently. It has a battery, the manual confirms. It also has a charger. But all I need to do is to put the toothbrush on the charger.

How does that work? Both parts are plastic covered.
Yes, a Sonicare product.

Danish Deshmukh asked:


Backup time of a U.P.S or inverter depends on current or voltage of the battery ?

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….