Re-chargable batteries

[anotheoldgit]

Why do some maufactures of toys etc tell you not to use re-chargable batteries in their products?

[BT76]

Maybe because they have a deal going on with companies who do not make re-chargeable batteries? A battery is a battery and i dont think a toy could tell the difference, its all about get more money from your pocket into their tills.

[Gandy]

It's to do with the way they discharge. The amount of energy you can get out of a battery is very depenent on the rate of discharge of the battery and the temperature. If you try to pull a lot of power from an alkaline battery, the battery will die quickly with a lot of power still strapped inside the batter. You can pull 100mA from a standard AA battery for about 25 hours, but you can only pull 250mA for about 8 hours. Things get much worse with even higher discharge rates or when the temperature is low. aT -20C, a standard AA will last only 1/8 as long as it will at room temperature under high discharge rates. Lithium batteries are better than standard alkaline batteries under high drain conditions and much, mcuh better than standard alkaline batteries in the cold.

[qapmoc]

It is because rechargeable batteries have a very high maximum short term power output under short circuit conditions, meaning that if something goes wrong it is possible for the batteries to give enough energy (for a short time) to make the wires red hot and set fire to something.

True example : My son put the batteries in my camera wrong and it made the metal connection in the cover hot enough to melt the plastic within seconds.