smart battery won't charge

[grant fair]

I recently discharged the battery in my Toshiba laptop (an old 410CDT) and it is taking no charge at all, all of a sudden. How can I fix this? The recharger is part and parcel of this laptop.<p>Grant

[dyarker]

Does the laptop run when power brick is on AC?<p>Remove and install the battery a couple of times. The contacts may be dirty. In and out may wipe off some crud.<p>By "discharged", do you mean you ran the laptop till it died, or you took the battery out and did something to it?

[Chris Smith]

Make sure the terminals inside the battery box also arent over heated, and bent or broken.

[bodgy]

Don't forget some laptop batteries that have smart charger circuits built into them also combine things like in built end of life recognition (this is always on the conservative side)as well as annoying things like serial number recognition so that you can't whip the battery out and either repack it or bung it in another brand laptop.<p>
Colin

[Externet]

Hello Grant.
-Is it a NiCd, a NiMH, or a LI-ion pack ?
-What is the nominal voltage of the pack and what is its voltage reading out of the laptop ?
-What is the voltage at the laptop battery terminals with the charger connected and no battery ?
Miguel

[grant fair]

Dale - by discharged, I mean I ran the computer in DOS until the battery-low light on the laptop was flashing, so I turned the machine off. I had been running it for about 3 hours at that time; I have never used the machine for that long a period before.<p>Grant

[grant fair]

Dale - yhe laptop runs fine when the AC cord is plugged to the back of the machine (and plugged into an AC outlet <G&gt .<p>Grant

[dyarker]

Then probably time for a new battery.

[grant fair]

The battery is now charging, after taking Dale's advice to remove and replace the battery. I also cleaned a bit of grunge off one terminal. So it looks like it is fine, and the problem was just a bad connection.<p>From looking at discharge curves for LI ion batteries I wondered if it was dead, because it had kept the computer running for 3 hours before it stopped. That didn't seem like a battery at the end of its life span, but I was far from sure. Anyway all seems to be well now. Thanks to all who replied!<p>Grant