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Notebook Battery Chargers?
Nilatir asks: "Here at the University where I work we're checking out Dell notebooks to the students in the library and our main lab. While this is proven to be good for the students I'm having a hard time managing the batteries for the notebooks. By eliminating the floppy drives and using wireless APs to access network shares we were using two Li-Ion batteries in every Latitude and getting almost 8 hours of life a day from them. But, due to some students undying dependence on floppy disks, we were forced to drop down to one battery which will only last half the day at best. We now have an extra battery for each notebook with no way to charge them (even Dell's docking station has no charging bay). Have any slashdotters run into a problem like this and how you all resolve it? Does anyone know of external battery charging station for notebook batteries?" Will laptop makers ever learn that this is one of those accessories that would sell like hotcakes?
I have the same problem, and we actually try to use one of the laptops that hasn't been checked out yet to top off the batteries. It's a pain in the ass, but at least the Latitudes have the LED battery indicator on the battery, and stop flashing the laptop power light when the tthings are charged.
It's one of the most damned expensive external chargers I've ever seen, though.
I know Compaq, HP, and some specialty educational "mobile lab" companies make laptop charging stations. They have a space for the laptop and one extra battery for each. The one I looked at even had a spare power plug so the student can go to the station, plug in the laptop, swap the batteries, and unplug the laptop without shutting down or losing their work. I'm not as familiar with Dell, but at least call their education department and check with them. If they sell mobile labs, it's a good bet that they have something similar.
Jason
"FORMAT C:" - Kills bugs dead!
The Dells already do this to some extent, although to be safe you probably would want to (need to?) temporarily suspend the computer to do it. I can attest that my Dell Inspiron 8200 has an internal capacitor that is at least powerful enough to allow me to suspend (not "hibernate"; I mean a real "everything-is-still-in-RAM" suspend, not suspend-to-disk) the computer, swap batteries, and pick back up at whatever I was doing 10 seconds ago.
The extra terminals are usually control logic. A little investigation can reveal what they are, or you can do what I did: I got a half dozen Compaq notebook batteries for $5/each surplus and smashed up the cases and took out the cells, and made my own packs sans logic (with charger chip). I forget what I was doing with them now though, but with 20 or so li-ion cells you have about the same power as a mid-size lead acid.
Lead acid batteries don't need much in the way of charging intelligence. If they're 12V, the cheapest solution is to use a trickle-charger from an auto store.
The coin cells, heh.. well, I needed to use my meter and back in the day the only one I had was a crummy radio shack piece of junk that took coin cells. I figured if I pulsed some current into 'em, I'd get some measurements. It worked until I got greedy and did it a few times, then it went off with a LARGE bang and almost embedded itself into my arm. Not recommended.
..don't panic