MacBook battery: how to treat it?

[Slartibartfast]

What is the best way to use/recharge the macbook battery: drain it all the way down and the recharge it all the way back, or keep it as full as possible all the time? I did the calibration specified in the little manual that comes with it, but it doesn't say whether you should use either recharge method.

 

[bluetech]

You definitely need to cycle the battery (need not be all the way down and back again). Leaving it fully charged all the time will dramatically shorten battery life.

 

[Slartibartfast]

Ah, good, that's what I've been doing. I know some rechargeables are better if you keep them full, so that's why I was curious. Thanks

 

[lessthanjakejohn]

Read several sources on Google.com There are a lot of factors when it comes to Li-ion battery life.

Wikipedia says this:

* Unlike NiCad batteries, lithium-ion batteries should be charged early and often. However, if they are not used for a longer time, they should be brought to a charge level of around 40%. Lithium-ion batteries should never be "deep-cycled" like NiCd batteries.
* Li-ion batteries should be kept cool. Ideally they are stored in a refrigerator. Aging will take its toll much faster at high temperatures. The high temperatures found in cars cause lithium-ion batteries to degrade rapidly.
* Lithium-ion batteries should never be depleted to empty (0%).
* According to one book[6], lithium ion batteries should not be frozen. Note that most lithium-ion battery electrolytes freeze at approximately −40 °C, which is much colder than the lowest temperature reached by most household freezers.
* Li-ion batteries should be bought only when needed, because the aging process begins as soon as the battery is manufactured. [citation needed]
* When using a notebook computer running from fixed line power over extended periods, the battery can be removed and stored in a cool place so that it is not affected by the heat produced by the computer. [citation needed] (However, a notebook computer's battery prevents sudden loss of the data in memory during power failures and brownouts. Reasonable alternatives are the use of an older lithium ion battery or an external uninterruptible power supply.)

Personally, I plug in my notebook whenever possible and then remove the battery when it is charged.

 

[the@ntipop]

Double post.

 

[the@ntipop]

Also note that onboard logic will never let you completely drain your battery. I charge it when it gets under 20% unless I know I'll need to use it for a couple hours without a plug. My battery has gotten to "0%" a couple times when I leave it sit in standby for too long. I haven't lost much if any capacity with this method and haven't recalibrated it in the 3 months I've had it (should do one soon though).