Computer turns off on battery

[mtlve]

I have an ~3yr old powerbook G4 (only owner).

For the last two weeks, it has started to power off randomly when it is running on the battery. On a fully charged battery, I can get ~1.5 hrs of use before it turns off. I then have to plug it in and start the computer up again. The date has then been reset to the 1960s. The battery typically shows no charge after I turn it back on, but I no longer get the low battery warning and it now turns off instead of going to sleep. The last time it powered off, the battery indicator on the back of the computer said that there was absolutely no charge. When I got the computer back on, it was half way charged. I have no problems with powering off when the computer runs off the AC cord.

Any one have any id about what is going on with my computer? I am pretty illiterate when it comes to computers, so I am unsure.

Your help is grealy appreciated

[harryb2448]

Better is we knew what model PowerBook. Some have an internal PRAM battery and the change of date to 1960 is a sure sign the battery (if fitted) needs replacing.

Should the PowerBook have no PRAM battery, sounds like the Li-on is on the way out.

[mtlve]

It is a 12in Powerbook G4 purchased around Dec 2005. It is a Lithium ion battery that was replace in the recall ~2 yrs ago. I guess I should just order a new battery.

Better is we knew what model PowerBook. Some have an internal PRAM battery and the change of date to 1960 is a sure sign the battery (if fitted) needs replacing.

Should the PowerBook have no PRAM battery, sounds like the Li-on is on the way out.

[harryb2448]

A lot depends on how frequently you use the PowerBook running on battery. Different manufacturers mention the life as about 300+ recharge cycles. Twice a week recharge for say 2/3 years and you are getting close to the life of the battery.

[goosemiet]

I have just registered for the forum to get information about a similar problem: shutdown without warning when the battery gets low. Mine is a MacBook laptop purchased September 2006. Battery life is ~2 hrs and hasn't degraded since purchase (kind of low, however, no?). I have reset the PMU several times, but this has had no effect whatsoever. Owned many macs for many years, don't have a clue what;'s going on. Really infuriating because the machine otherwise operates flawlessly. I have lost important work on a number of occasions.