Brand new battery, 96% capacity?

Kona*

Kona*

Kona*

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Joined
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Newcastle upon Tyne
Hey :)

I've just got a hold of a 2nd hand Macbook and bought a new battery for it. When I installed it yesterday it had a capacity of 5014mAh (New is 5020mAh) and after doing a full calibration cycle (as per Apples instructions) it's now showing 4847mAh!

Will this creep back up as I continue to cycle the battery or has it lost 4% of it's life in one whole day? I'll get it send back as faulty if this is the case.

Cheers,

Craig
 
You don't really need to do a full calibration if you've bought it new.

I'd say it will improve slightly as you use it, don't worry :)
 
EVH said:
You don't really need to do a full calibration if you've bought it new.

I'd say it will improve slightly as you use it, don't worry :)
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That's OK then, cheers :)

I only done a full calibration as I had a problem with the battery not charging above 99% - that issue is fixed now but I just wanted to check I hadn't shagged the battery by doing a full cycle!
 
You're meant to leave the battery charging for a good 5hrs before completing the full calibration.

Leave it empty for 2hrs..

Then re-charge the battery to full for another good 5hrs.
 
The Lithium ion batteries degrade faster if they're just sat charged at 100% all the time, so ensure you run the batteries down once a week.

My newish MBP battery full charge, after 3 months or so, is 5326 mAh.

Also battery life will be affected by anything plugged in or additional applications running in the background - even screen brightness.
 
EVH said:
You don't really need to do a full calibration if you've bought it new.

I'd say it will improve slightly as you use it, don't worry :)
Click to expand...

EVH said:
You're meant to leave the battery charging for a good 5hrs before completing the full calibration.

Leave it empty for 2hrs..

Then re-charge the battery to full for another good 5hrs.
Click to expand...
NickK said:
The Lithium ion batteries degrade faster if they're just sat charged at 100% all the time, so ensure you run the batteries down once a week.

My newish MBP battery full charge, after 3 months or so, is 5326 mAh.

Also battery life will be affected by anything plugged in or additional applications running in the background - even screen brightness.
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No! No! No! No! (orange text = Misinformation)

there are three possible reasons why the capacity of the battery has dropped:
  1. The battery was old but unused when you bought it. Li-Ion batteries lose capacity over time no matter how they're stored. if the cells in the battery were manufactured 6 or 7 months ago, it's easily possible that they've lost 4% capacity.
  2. The MacBook could continue charging the battery when it's fully charged if the computer's turned off. all but the most sophisticated battery management control systems lose intelligent control when the computer's off and just continue feeding current into the battery, Li-Ion's get VERY upset if you overcharge them.
    Dumb-charging a Li-Ion at it's max charge-rate for just 10 minutes can cause it to lose over 50% of it's capacity. luckily, laptops usually only charge batteries at 10% of their max charge-rate, and even less when they're off.
  3. lastly, Li-Ion batteries lose capacity simply by being discharged. it's definitely possible that fully discharging it has reduced its capacity by 4%

doing a full charge-discharge cycle is only going to waste the batteries highly limited lifespan. you only need to do one once a MONTH at the most, and even then only if you've not used it for more than a fortnight (Li-Ion batteries lose charge over time, and the capacity-monitoring circuit can't measure this).

Li-Ion batteries are rated to last only 500 Cycles before they get to FIFTY PER-CENT capacity. needlessly performing cycles is just silly.

lastly, if you're going to be leaving a battery unused for a long (greater than a fortnight or so), then discharge them to about 70% charge, and don't store them in a warm environment - heat also kills Li-Ion batts :(

Overall, Li-Ion batteries are annoyingly persnickety things.

by following these steps, i've managed to keep the Li-Ion battery in my thinkpad at 105% capacity (design capacity: 56.16Wh, current total capacity: 57.13Wh) for over three months.
 
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Also battery life will be affected by anything plugged in or additional applications running in the background - even screen brightness.

^^ the additional current draw by these will reduce the time you will have available on battery power. Perhaps a better way of saying it..
 
Aod said:
No! No! No! No! (orange text = Misinformation)

  1. lastly, Li-Ion batteries lose capacity simply by being discharged. it's definitely possible that fully discharging it has reduced its capacity by 4%
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Bah :(

Thanks for the information, I've copied & pasted it for future reference.
 
NickK said:
Also battery life will be affected by anything plugged in or additional applications running in the background - even screen brightness.

^^ the additional current draw by these will reduce the time you will have available on battery power. Perhaps a better way of saying it..
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ah yes, that makes more sense. the was it was originally phrased made it sound like they'd diminish the battery capacity itself

Kona* said:
[/LIST]
Bah :(

Thanks for the information, I've copied & pasted it for future reference.
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it's not a problem, and don't worry about it. laptop batteries die all the time. i had a toshiba that was only two years old before it got to precisely 0% battery capacity... probably because i left it charging all the time... but i know better, and now, so do you :)
 
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How is what I posted mis-information?

That is the procedure Apple recommend.. I'm not disputing it will harm the battery if you do it often, but if he wants to do it; that's their recommendation.
 
EVH said:
How is what I posted mis-information?

That is the procedure Apple recommend.. I'm not disputing it will harm the battery if you do it often, but if he wants to do it; that's their recommendation.
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I realise why Apple publish the information on how to calibrate your battery but after reading what Aod said I think they should at least have a disclaimer telling you that it could potentially reduce the capacity of your battery!

On another note, battery is down to 4831mAh Capacity (not capacity remaining) now and it's been unplugged since I posted this thread, how can it loose capacity when it's unplugged...

I wish I never installed coconutBattery now, ignorance is bliss and all :p
 
Kona* said:
I realise why Apple publish the information on how to calibrate your battery but after reading what Aod said I think they should at least have a disclaimer telling you that it could potentially reduce the capacity of your battery!

On another note, battery is down to 4831mAh Capacity (not capacity remaining) now and it's been unplugged since I posted this thread, how can it loose capacity when it's unplugged...

I wish I never installed coconutBattery now, ignorance is bliss and all :p
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it could just be shagged?

i know what you mean about battery-ignorance. i obsess over my thinkpads battery details like a hawk.

EVH said:
How is what I posted mis-information?

That is the procedure Apple recommend.. I'm not disputing it will harm the battery if you do it often, but if he wants to do it; that's their recommendation.
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whether it was said by apple or said by Joe Bloggs, it doesn't matter - it's incorrect advise and following it will lead to a degradation in battery capacity
 
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Aod said:
it could just be shagged?

i know what you mean about battery-ignorance. i obsess over my thinkpads battery details like a hawk.



whether it was said by apple or said by Joe Bloggs, it doesn't matter - it's incorrect advise and following it will lead to a degradation in battery capacity
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Fair enough.. no need to be rude though.

There is plenty of mis-information on these forums :p
 
NickK said:
The Lithium ion batteries degrade faster if they're just sat charged at 100% all the time, so ensure you run the batteries down once a week.
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Wrong, it actually shortens the life of a li-ion battery if you run it down once a week.....


A lithium-ion battery provides 300-500 discharge/charge cycles. The battery prefers a partial rather than a full discharge. Frequent full discharges should be avoided when possible. Instead, charge the battery more often or use a larger battery. There is no concern of memory when applying unscheduled charges.
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source http://www.batteryuniversity.com/parttwo-34.htm
 
MikeHunt79 said:
Wrong, it actually shortens the life of a li-ion battery if you run it down once a week.....



source http://www.batteryuniversity.com/parttwo-34.htm
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EVH said:
Fair enough.. no need to be rude though.

There is plenty of mis-information on these forums :p
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i wasn't rude - just abrupt. i wanted to ensure that the OP didn't damage his battery further.
 
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I thought that the Apple routine of letting the laptop put itself to sleep didn't in fact completely discharge the battery.
 
Feek said:
I thought that the Apple routine of letting the laptop put itself to sleep didn't in fact completely discharge the battery.
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all lithium-ion batteries contain electronics which prevent the cells from being fully discharged, because doing so will kill them stone dead.

nevertheless, Li-Ion batteries don't like being discharged at all, let alone fully*, so i wouldn't do it unless i had to.

*as i said, no Li-Ion battery is ever "fully" discharged - they're taken down to about 2% or 3% remaining before the protection circuitry cuts them off.
 
Coincidentally my battery health has dropped today from 100% to 99%

battery.png


It gets used on power most of the time, when I'm not using it I just close the lid to put it into sleep mode and put it by the side of my chair with the power still connected. It gets used most days.

Should I really be doing something different?
 
iStat Pro, there's a menu bar version as well, iStat Menus which I use to just monitor CPU and memory use but can do a lot more. Both are free.

This is the bit I have sitting in my menu, CPU on the left, memory on the right:
istatmenus-20091024-210532.png
 
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