Notebook batteries (or: Am I gonna blow it up?)

I’m trying to get a replacement battery for my wife’s (ancient) notebook. It’s a Compaq Presario 1200XL-118.

I 'm looking around the Web for good deals on a replacement (It’s not worth spending too much on). And I keep coming across examples like this. Notice the specs on it: Li-ion, 14.4 V, and 3200 mAh.

Now, I’d like a Li-ion battery for this computer, but the OEM battery in it is a Ni-MH that says it’s 9.6 V and 4500 mAh. (although, it’s probably got more like 100 mAh of usable capacity after 4 years).

So, what’s the deal? Are the web vendors mistaken in their compatibility? (There are an awful lot of them that say the same thing.) How can the battery running at 14.4 V be compatible with a notebook whose original battery was only 9.6? Should the notebook have a voltage regulator that will accommodate? Or will things blow up if I put this battery in?

The packaging is undoubtedly the same, so it will physically fit. But even though I can put it in, should I?

FWIW, the AC adaptor’s output is 19V, so that’s what’s going into the computer when it’s running off AC (and it has to just about all the time.) Obviously, there’s some voltage regulation there, but that doesn’t mean it will do it for the battery.

You can talk to http://www.advanced-battery.com/ as they are experienced in rebuilding battery packs etc.

I’ve been working on Compaq’s lately that also have this situation. It’s a side effect of LiIon vs. NiMh voltages, lazy EEs and such. Don’t worry about it.

If you wander around the Compaq (now HP) web site for your model you may be able to find fairly detailed tech info on power requirements (I did for my model).