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Is it benefical for battery heath to deepcycle once a month?

  • Yes I know for a fact.

    Votes: 5 12.2%
  • Yes I think so.

    Votes: 15 36.6%
  • I don't know.

    Votes: 12 29.3%
  • No, I don't think so.

    Votes: 5 12.2%
  • No, I know for a fact that it does not matter.

    Votes: 4 9.8%

  • Total voters
    41
  • Poll closed .

Philflow

macrumors 65816
Original poster
May 7, 2008
1,276
3
Is it benefical for batteryhealth to deepcycle once a month?

This is what Apple says on battery use for notebooks:

If, on the other hand, you use a desktop computer at work, and save a notebook for infrequent travel, Apple recommends charging and discharging its battery at least once per month.
http://www.apple.com/batteries/notebooks.html

My question is: is this beneficial for battery health?
or is this only for calibration purposes?
 

ayeying

macrumors 601
Dec 5, 2007
4,547
13
Yay Area, CA
I see no major benefits unless you have a problem with your battery. I never calibrated any of my laptop batteries, just used it as is and I always end up with great battery life and health. The only major concern I had with one of my laptop was heat. The heat basically destroyed the battery.
 

HotAir

macrumors member
Apr 5, 2008
61
0
Hollywood CA USA
Seems like a hassle to have to deal with that on top of everything else. I thought batteries were beyond having to do this routine nowadays.
 

jcb10

macrumors regular
May 14, 2008
132
21
I believe it does help

I've had iBooks long enough (one from 2000 and one from 2002, with two batteries for each) to try this out and while all the batteries are now down to very slight charges, I have found that reconditioning now and then does give a small advantage.

The second iBook was for my wife and she used one battery constantly for about a year with no reconditioning, and it's basically dead. The second battery, reconditioned regularly, has lasted for more than four years.
 

BanjoBanker

macrumors 6502
Aug 10, 2006
354
0
Mt Brook, AL
I have always conditioned/calibrated my laptop batteries. The battery in my 12" PB was replaced by a recall, and the new one is still in use. I have found I have a better service life from the batteries I condition. Is it necessary? I have no idea. Has it been beneficial to me? You bet, so I do it monthly. It could be the placebo effect, but I do it anyway. :D
 

Alkiera

macrumors regular
Mar 11, 2008
109
0
The 2 biggest factors in Lithium Ion battery life are temperature and current capacity. Storing a L-Ion battery in a warm place while at full charge will drastically reduce it's capacity. Same temp, but at 40-50%, will lose much less. Storing it in a cooler place is always better.

It's a good thing that the heat in these seems so focused in the CPU/power port area; I'd guess it will have much better battery life than the Dell I had where the battery got very hot, even when sitting plugged in.
 

Darge13

macrumors newbie
Feb 18, 2008
28
0
Most of the post I read regarding this issue are people who leave their laptop plugged in all the time and rarely use the battery. Then one day they go to use it and get no life out of it.
 

Philflow

macrumors 65816
Original poster
May 7, 2008
1,276
3
I really believe in this deep cycling once a month now.
My battery health went up to 99,8%.

(5114/5122)
 

portent

macrumors 6502a
Feb 17, 2004
623
2
Absolutely Not!

A true deep discharge will KILL YOUR BATTERY!. It is the absolute WORST thing you can do to a LiIon battery.

Keep in mind that a "deep dischage" is not the same thing as "running the battery down to 0%. A deep discharge occurs when you run the battery down to 0% and then let it sit for a prolonged while without charging while the internal resistance drains it further.

At this point, the battery will not hold a charge at all, or will only supply a few seconds of power before shutting off.

http://www.apple.com/batteries/notebooks.html
If you store a battery when it’s fully discharged, it could fall into a deep discharge state, which renders it incapable of holding any charge.

(Some of you may remember the days when full discharges were necessary to prevent the "memory effect" in your batteries. This was called "reconditioning" and is not the same thing as "deep discharging" nor is it quite the same thing as "calibrating." Calibrating does not affect the power storage of the battery; it merely keeps the power gauge on the battery accurate as the battery's capacity changes over time.
 

wordy

macrumors regular
Feb 26, 2008
233
0
Toronto
Does anyone know for certain if LiIon batteries suffer from any memory effect?

I was lead to believe that they did not have a memory effect as opposed to others like NiMH etc.
 

alphaod

macrumors Core
Feb 9, 2008
22,183
1,245
NYC
Does anyone know for certain if LiIon batteries suffer from any memory effect?

I was lead to believe that they did not have a memory effect as opposed to others like NiMH etc.

No memory effect, but the cells do die and they don't hold their charges that well when put into storage.
 

wordy

macrumors regular
Feb 26, 2008
233
0
Toronto
Thanks for that.

One more question, does the indicated "charge time remaining" refer only to the quick charge or is it the total (i.e. quick + trickle)?

I've noticed that the time to full charge seems to be less when charging from a depleted state rather than from say 60% charge.
 

Mechcozmo

macrumors 603
Jul 17, 2004
5,215
2
Battery information:

You should discharge/recharge a notebook battery fully at least once a month. As mentioned previously, not a "deep discharge", but unplugging your laptop for a couple of hours to keep the electrons from growing stagnant isn't hard to do and is plenty healthy.

Also, calibrating your battery is a _must_ to get proper readings. Just got an iBook than went from 0:40 to 0:00. Read up on Apple's site how to calibrate your Mac (Safe Sleep changed things a bit).

My four-year-old 12" PowerBook's battery still lasts well over four and a half hours-- and it's the original battery.
 

Mechcozmo

macrumors 603
Jul 17, 2004
5,215
2
No memory effect, but the cells do die and they don't hold their charges that well when put into storage.

Apple recommends a 50% charge, removal from whatever unit they're normally in, and storage at (if I'm remembering correctly...) room temperature.
 
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