Macbook Battery

[Jakee]

Hi,

I've had my Macbook for about 2 years now and so far its been a smooth run! :Blushing: However, I'm now getting problems with the battery. It shows 30% and then just shutsdown! no warning, but when I plug it in it then shows 0%. It's like the reading it not accurate. Is there a way to fix this problem?

Many thanks.

 

[cwa107]

Yep, it's time for a new battery. The typical life-cycle of a laptop battery is about 18 months - longer if you keep it mostly charged, shorter if you routinely drain it.

 

[Zoolook]

Your battery should last about 300 cycles, before dropping dramatically, but the shut down issue when there's still 30% or so is a known issue.

The MacBook batteries actually like to be drained regularly, but not all the way to empty every time. The worst thing to do is leave your MacBook always plugged in, or do deep discharges too often, somewhere in the middle is optimum.

 

[zcamel]

I was just given a new battery for my 2-year old Macbook from the Apple Store. Basically, it wouldn't even hold a charge anymore, so as soon as you pulled the chord out (or tripped over it) the computer immediately died. I just went in there and told them the battery doesn't hold a charge anymore and they replaced it, no questions asked. I also had more than a 400 cycle count. I guess it just depends on how hard you can pimp the Genius at the Genius Bar.

In regards to the definition of a cycle, I have been keeping a close watch on my new battery and the Macbook registers a cycle even if the battery doesn't deplete completely. In other words, if I have it plugged in and the battery is fully charged, then I unplug it for a couple hours with the battery halfway depleted, then plug it back in until it's fully charged, the Macbook will copy that as a cycle. Crappy I know, but that's how it is...it's best to leave your Macbook plugged in and cycle it fully at least once a month.

 

[cwa107]

Your battery should last about 300 cycles, before dropping dramatically, but the shut down issue when there's still 30% or so is a known issue.

The MacBook batteries actually like to be drained regularly, but not all the way to empty every time. The worst thing to do is leave your MacBook always plugged in, or do deep discharges too often, somewhere in the middle is optimum.

In my dealings with notebook batteries, I've found that the longest-lasting batteries are those that are left charged constantly. I have read online that maintaining a semi-full charge is the key to longevity, but my experience over hundreds of different laptops has proven that it's fine to keep them perpetually charged. I'm sure one could eek out a few extra cycles in following your advice, but I don't think it's anywhere near as detrimental as constantly doing complete discharges.

 

[Zoolook]

In my dealings with notebook batteries, I've found that the longest-lasting batteries are those that are left charged constantly. I have read online that maintaining a semi-full charge is the key to longevity, but my experience over hundreds of different laptops has proven that it's fine to keep them perpetually charged. I'm sure one could eek out a few extra cycles in following your advice, but I don't think it's anywhere near as detrimental as constantly doing complete discharges.

Even for Lithium-ion based batteries? I can't disagree with your personal experienc ('cos that's your personal experience), but the accepted wisdom is that current generation Lithium-Ion batteries are designed with regular, partial discharges over an extended period of time in mind, making them ideal for mobile phones and iPods, as well as notebooks. The very worst thing to do, is to leave them plugged in constantly, because it means they sit at 100% charge, often at high temperature.

Guidelines for long life
- Unlike Ni-Cd batteries, lithium-ion batteries should be charged early and often. However, if they are not used for a long time, they should be brought to a charge level of around 40%–60%. Lithium-ion batteries should not be frequently fully discharged and recharged ("deep-cycled") like Ni-Cd batteries, but this is necessary after about every 30th recharge to recalibrate any external electronic "fuel gauge" (e. g. State Of Charge meter). This prevents the fuel gauge from showing an incorrect battery charge.

-When using a notebook computer running from fixed line power over extended periods, the battery should be removed,[36] and stored in a cool place so that it is not affected by the heat produced by the computer.

 

[cwa107]

Even for Lithium-ion based batteries? I can't disagree with your personal experienc ('cos that's your personal experience), but the accepted wisdom is that current generation Lithium-Ion batteries are designed with regular, partial discharges over an extended period of time in mind, making them ideal for mobile phones and iPods, as well as notebooks. The very worst thing to do, is to leave them plugged in constantly, because it means they sit at 100% charge, often at high temperature.

Yep, I'm referring to the Dell Latitude models (XPi through "C" and modern day "D" series machines) I support at work. I have laptops from low-utilization areas (i.e. executives that rarely ever remove them from the dock, they are merely assigned to them as a "status symbol") that have 3+ year old batteries that are still able to provide about 80% of their original capacity. Heck, I've got a few old Latitude C510s (2003 vintage) that are still on their original batteries and can run for 2 hours+. I know it runs contrary to conventional wisdom as I've read articles similar to that which you've quoted, but the proof is in the pudding, so to speak.

 

[RONE]

Fully discharge your battery (use the computer until it shuts down), then leave it unplugged overnight. The next day plug it back in and charge it all the way back to 100%. This should "reset" what your battery knows about its charge capacity.