Laptop Batteries to power robots

[SeagullOne]

Is it possible to use a laptop battery to power a robot.

I know its foolish to use a laptop battery to power a laptop computer and the robot's electronics at the same time because the battery can't handle the load, but suppose I had a separate laptop battery powering the robot's on-board computer and one or two other laptop batteries powering the rest of the robot's electronics. I've seen some laptop batteries that supply over 40 Ahr, and they would be much lighter than Sealed Lead Acid batteries of that caliber.

Thanks.

[airman00]

you know that laptop batteries are lithium rite? http://www.societyofrobots.com/robotforum/index.php?topic=2572.0

[Admin]

In theory it is possible. If you look at the battery, you will notice a bunch of pins (not just ground and power). The laptop battery has built in electronics, and you will have to figure out how to interface with it.

Im sure if you google it something will come up . . .

[david_or_johnny]

Lithium ion and lithium polymer batteries except those used in the power tool and radio control industries are notoriously bad at sustaining high discharge rates such as those a pair of moderately powered motors can develop. With high discharge, they will expand and pose a safety risk. Also, watch out for discharging and charging: Lithium batteries do not taper off in voltage as they near their maximum capacity; they keep on going up and up. You need a cc/cv (constant current followed by constant voltage) charger to be safe. And when discharging, if you overdischarge the pack beyond a safe limit (I cannot remember the number per cell) you will no longer be able to use the pack.

In two words: be careful!

[dj sures]

i use sub-c rechargeable nicad cells . u can get them from hobby shops . 7.2v , 3,600 mha ..

[SeagullOne]

Great advise, everybody. I think I'll use something safer for now. Those sub-C rechargeable ni-Cads sound great, dj sures. I think I'll check em' out!

[david_or_johnny]

Look for NiMHs.

Actually a very, very good pack is the Radio Shack GP3300s. Very high quality high discharge 3300 mAh cell from reputable manufacturer Gold Peak, for $19.99.