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smeowly

macrumors newbie
Original poster
Oct 26, 2008
16
0
hey guys, sorry if this has been discussed to death already but i have some burning questions re: battery care


1. if the battery is fully charged and you leave it plugged in, won't that be overcharging the battery and won't it decrease the battery's longevity? or does the power cut automatically when it's fully charged?

2. if you charge the battery only halfway and have to stop charging because you need to bring the laptop away from the power source, does that affect the battery longevity also?

3. i heard that lithium batteries should never be completely discharged. so is it advisable to start charging when your power falls to 20% and not let it completely discharge except to callibrate it every month?
 
1. The battery never overcharges. It cuts off the charge at 100%.

2. No

3. A complete discharge (deep cycling) is actually good for lithium batteries (www.batteryuniversity.com)

Just use your laptop and forget about the battery. Its designed to be used frequently and the people who report the healthiest batteries (those that have the highest capacity the longest) are the ones who never think about it.
 
1. The battery never overcharges. It cuts off the charge at 100%.

2. No

3. A complete discharge (deep cycling) is actually good for lithium batteries (www.batteryuniversity.com)

Just use your laptop and forget about the battery. Its designed to be used frequently and the people who report the healthiest batteries (those that have the highest capacity the longest) are the ones who never think about it.

thanks!

all this time i've been using my blackbook and now new macbook i've been taking out the battery when i'm at near a power source if it's already fully charged! i feel so silly!
 
well i did an experiment... i regret it.

i do the deep cycle method mentioned before... it works. truly.

but the battery DOES overcharge. i clocked my mac's battery life from 100% to 7% and it lasted 3:41... (almost) perfect!!! the next day i did the same but after recharging... i left it plugged in, while i was using it and after shut down. left it plugged in overnight... the day after (i gave it a rest for 30 min or so) i clocked it again... from 100% to 6-7%.... !!!!:eek:!!!1:56!!!:eek:!!!!

SUCKS!! thats exactly 45 min less... and thats just ONE time overnight...

i dont know about the removing the battery... i works perfectly for me!
havnt had any probs... other than when i used it without the bat. and use it in my bed... it can shut down easily because of the mag safe... but. other than that in a desk it works.
 
Wow, just stop worrying about it. Batteries are meant to be used and it's gonna lose its charge capacity over time, no matter what you do.

They're not that expensive to replace either. If say after 2 years you still have your MacBook and you find that the battery life is not good enough for you, you're only going to have to shell out like $100. That's no price to pay for having peace of mind and not being all OCD about your battery.
 
that is true...
i mean for the $1,499 value of the computer, $100 bucks aint that much to keep it alive for 2 or more years.

still ill take the battery out when im on ma desk... cuz it makes the computer heat up less for some reason.
=D
 
that is true...
i mean for the $1,499 value of the computer, $100 bucks aint that much to keep it alive for 2 or more years.

still ill take the battery out when im on ma desk... cuz it makes the computer heat up less for some reason.
=D

You probably aren't doing anything that would use up so much CPU that you would notice that you are running at half speed. Should you accidentally remove the magsafe while you are working without your battery, your Mac will immediately shut off and all your unsaved work will be lost. Not something I would chance.
 
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