Laptop battery problem

[Biggsy]

My DELL Inspiron 1501 has previously been fine with the original battery, but has suddenly failed to recognise it and displays the following message when I fit it (and a similar one when I turn on the computer):

"The model number for the primary battery cannot be determined.  This will prevent any present battery from charging".

I have tried resetting the computer and removing and reinserting the battery - makes no difference.  The battery is currently almost fully charged, and works, but of course I'm concerned that I won't be able to recharge it.

The only thing I've done differently than usual recently was to use the computer with the battery and let it run right down (though the computer has charged it since then).  Normally I use the AC adapter most of the time and the battery only for brief periods.

Thanks for any ideas or suggestions.

[rusky]

Probably a knackered battery

[Biggsy]

It's not knackered in terms of taking a charge (because it did it once since I last ran it down) and delivering power.  But could there be a knackered chip in it?  Or is it more likely to be something to do with the computer than the battery?

[TimO]

A lot of modern battery devices do have microprocessors integrated with the battery, as far as I understand it for two main reasons (i) Fully discharging the battery normally damages the battery, so the microprocessor will shut it down before this happens (ii) The internal resistance of these batteries is often so low, that they can produce a lot of current if requested.  Enough to cause a fire, so the microprocessor will limit this as well to reduce the risk of an accident happening.  The second point can be dealt with by simply using a fuse, but the former requires more intelligence.

The same device also often looks after the charging process, and saves on other electronics in the charger itself, which can be fairly crude if the battery looks after the charging process.

It does sound like the microprocessor has gone casters up, which is a bit of a bugger.

[Biggsy]

Some good news:

I now suspect the computer is giving a false alarm rather than there being anything really wrong with the battery - because the Power Meter indicates the battery model number and says it's charging when the AC adapter is connected, and the percentage of charge remaining goes up.

The error message is annoying enough though.  It appears on every boot or resume from hibernation - and requires a key stroke to continue.  Not operating system related because it happens before the OS is loaded.

[TimO]

It's possibly worth looking in the BIOS settings, and see if something has spontaneously flipped for no good reason.  It's a bit of a long shot though, since I can't remember ever seeing any settings in a BIOS relating to batteries.

[border-rider]

It's possibly worth looking in the BIOS settings, and see if something has spontaneously flipped for now good reason.  It's a bit of a long shot though, since I can't remember ever seeing any settings in a BIOS relating to batteries.

When I changed the battery on an old Dell, I had to do a BIOS upgrade at the same time to enable the battery to be recognised, so you may be on to something.

[Biggsy]

Yes, thanks.  Unfortunately I haven't seen anything to do with the battery in the BIOS settings, though I will check more thoroughly.

[Biggsy]

A BIOS update seems to have fixed the problem