[Pixalo]

Apple has said that "some batteries" in its range of MacBook and MacBook Pro laptops have "performance issues".

The company has issued a software update to fix the issue and has offered to replace defective batteries.

"The factors causing the performance issues do not present a safety risk. You may continue to use your current battery," the company said.

Reports of problems, including swollen batteries, have been circulating since the laptops were launched in 2006.

In its support notes to users, Apple says battery packs which are "visibly deformed" are among the symptoms of battery problems.

The company advises users to install the update on all "MacBook and MacBook Pro computers and extra batteries that were purchased between February 2006 and April 2007".

If battery problems persist after the update, Apple has said users should contact their local Apple store or retailer and the firm will arrange replacement batteries free of charge.

Other symptoms of battery problems include:

# The battery is not recognised

# The battery will not charge and runs down quickly

In July last year the BBC News website was contacted by Apple owners who reported problems with their new laptops.

Technology professional Dave Verwer said: "I noticed my MacBook Pro would get down to 30% battery left and then shut off without warning.

"It had done this for a couple of weeks before I noticed that the battery case was swollen and coming away from the laptop casing."

Despite the issues, the MacBook range of laptops has been very successful for Apple.

Strong sales of the machines recently helped Apple sales soar to $5.2bn in the first three months of 2007.

[Gcane93]

I actually bought the MacBook Pro and yesterday I updated to Battery 1.2 firmware. After the upgrade I noticed I have longer battery life. Anybody notice the difference?

[Boofers]

I have the older power books, my wifes newer one fell under the battery recall. I don't know about the firmware for power books and I haven't looked,,,I can cook my lunch on mine,,,but it keeps working away and I have never had any trouble with it now for almost 4 years, I haul it everywhere almost everyday,,,,pretty durable and not so good battery life, I might be able to stretch it out to 2 hours depending on what I do. I am glad that the newer mac laptops will do better battery time,,,,I happened to be one of those people that see how jumpy the changes in screen movements are on windows and how smooth they are on a mac. My eyes are very light senceitive so maybe that's it. Other then that one grip, I could live with either if I had to.
Do you mind saying where your mac was assembled?

[sejanus]

Useful tip. My dual USB iBook would run for 5 hours on a charge. This MacBook Pro seems to struggle to reach 3 hours, although it does have a 15" screen

[Boofers]

I have a 15" too, my wife has the 12" same model but 2 years newer and can go pretty much 5 hours with no problem. Apple engineers have been working like crazy on the i-phone and I feel have left the computers to stand on their own. I would like to see them develope something unique to their computers to make them stand out again.