External Battery Packs, are they worth it?

Has anyone have any experience w/ external battery packs?
I was told that there is no way to monitor them while in use since the laptop doesnt recognize it as a battery so your system could shut down at any moment. Comments?

 

I used a "home built" external battery pack that I made out of a big 12 V battery and used a auto/air adaptor to power my laptop. In my case there was no way to monitor it directly other than using a Voltmeter. But it wasn't much of a problem sicne I would use that before using the internal battery. So once it died, I had my internal one to keep me going while I switched the 12V.

I don't know about the prefab ones since I've never tried one, but I don't thinkthat there would be a way to monitor them sicne they just go into the jack where the ac adaptor plugs in. I'd be interested in hearing first hand experiences though.

 

Depends on what you're talking about. I did a review of the APC universal battery. It plugs in via the power cord plug, so the computer views it as external power. But it also charges your internal battery and you can obviously see its status.

 

I have an Electrovaya PowerPad 120(I bought it from my brother, because it would work with my laptop, but not his, even though it was advertised to work with both. The plug on the cord for his was too short to gain contact). I would reccomend it. It is about 1/3-1/2" thick, and a bit smaller than my 15.4" notebook. It came with about 10 different cords, and you pick the one that fits your laptop. You just plug it in, and the laptop treats it as another power source. I get about 4-5 hours of battery life (and I have two internal batteries), and if I turn down the screen brightness while I recharge, the external can completely recharge one battery from 10%-100%, while also powering the computer. I find that an approximate 8 hours of battery life was probably worth it.

My brother also bought an external battery, which he used with his P4 laptop, it ran for about a half an hour. I was never able to test it on mine, so I don't know how it would compare, but I would say go for it, just check the return policy incase the cords don't work with your computer, because thats how I wound up with one.

 

and as far as the monitoring just use the external one first

 

Most of the externals, or at least all of the ones I have seen, have an LED power gauge, enough to let you know how much power you have, which works.