Modifying Power Source: Hook Up to Wall & Recharge

[iggybaseball]

I have a small electronic toy that takes 4 regular triple a batteries. I would like to open it up and see how much current the batteries are supplying, and then I would like to hook up a battery that I don't have to throw away. I would like to hook up the device to the wall to recharge it. I think that a lithium battery would work, but what device would i buy so that the battery would recharge from the wall? thanks

 

[chroot]

Why don't you just buy some rechargeable AAA batteries, and a recharger that fits them? You can buy such things at almost any store, including Wal-Mart and Sears and so on.

- Warren

 

[iggybaseball]

While this is certainly true (and certainly easier), I want to do it for the tinker factor and the knowledge. I would like to use this in a more complicated project later. Thanks a lot.

 

[chroot]

You cannot (and should not) build your own lithium-ion battery charger. Lithium-ion batteries are very sensitive to both under- and over-charge situations, and will readily explode if not charged (or discharged) properly. It is a testament to modern electrical engineering that something so potentially dangerous can be so well controlled.

As far as Ni-Cad and other rechargeable chemistries, you can buy battery packs and chargers from any of a million places on the web. I suggest http://www.batteryspace.com

- Warren