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npeterh · Oct 3, 2006, 11:17 PM

Hi

I wonder what is best for the battery. When I am hooked up to the wall power should I remove the battery or leave it in to preserve the battery? I mean after it has charged is it better to remove it so it doesn't "trickle charge"?

Thanks

/Peter

cambro · Oct 3, 2006, 11:52 PM

If you never use your battery and your laptop is plugged in all the time you should:

1) drain the battery to about 50% charge
2) remove it for storage

In short, use it or loose it...

chabig · Oct 4, 2006, 12:57 AM

"lose" it.

Think of the words that have two o's. They all sound the same...

caboose
goose
moose
foose (as in fooseball)
noose
loose

Then there is lose (pronounced Luze)

brokenjago · Oct 4, 2006, 01:07 AM

Originally Posted by npeterh

I wonder what is best for the battery. When I am hooked up to the wall power should I remove the battery or leave it in to preserve the battery? I mean after it has charged is it better to remove it so it doesn't "trickle charge"?

For the most part, this does not matter. As long as you go through one charge cycle per month (fully discharge and charge it once per month,) you should be fine.

That's what Apple says.

jwall · Oct 4, 2006, 01:11 AM

I would keep the battery in. If you are talking about a PowerBook or MacBook Pro, once it reaches full charge it stops charging and slowly drains (till it gets to 95 percent).

About every thirty days or so, pull the plug and run on Battery until you get down to around 10 percent and recharge. Battery's plugged in all the time are fine as long as they get some exercise... One way or another it will loose capacity over time.

More info on battery care is here:

Apple - Batteries - Notebooks

tooki · Oct 4, 2006, 01:25 AM

No, it'll lose capacity!

tooki

brokenjago · Oct 4, 2006, 01:36 AM

That's the second time in an hour I've seen that exact correction on these forums today.

ibook_steve · Oct 4, 2006, 02:20 AM

Leave the battery in, except for storage. Some Powerbooks run in reduced speed mode if the battery is not installed while running off of AC.

Steve

chabig · Oct 4, 2006, 02:28 AM

Originally Posted by ibook_steve

Some Powerbooks run in reduced speed mode if the battery is not installed while running off of AC.

I've never heard of that. References?

ghporter · Oct 4, 2006, 08:01 AM

I've seen that mentioned here a few times, but I can't for the life of me figure out why it should happen. It's counterintuitive-the computer should, if anything, run FASTER on AC and throttle down on battery ONLY.

However, as long as you occasionally use the computer on battery leaving it plugged in should be no problem at all. My wife's iBook stays plugged in about 95% of the time, and its battery had (as far as we could tell) exactly the same capacity two and a half years later as it did when it was new. (It was part of the recall, so now she has a NEW battery to play with.)

Sherman Homan · Oct 4, 2006, 08:20 AM

For whatever its worth, I had a co-worker who was a fanatic about taking the battery out when he was plugged in. After a year, the twist release and the battery contacts were so loose that the battery wouldn't seat firmly. So when he was on the road, the battery would lose contact and the iBook would drop dead, restart, etc.

Battery technology has come a long way from when I was a kid. Leave it in.

jwall · Oct 4, 2006, 10:13 AM

Originally Posted by brokenjago

That's the second time in an hour I've seen that exact correction on these forums today.

Sorry... I can't believe I did that, especially after reading the excellent spelling lesson provided by chabig.

phazedowt · Oct 4, 2006, 11:36 AM

The alternative (if you're worried about constantly removing and replacing the battery) is to occasionally unplug and work off of battery, even if you're near an outlet for extended periods of time. For example, I use my PB in my office for 8 hours or more at a time, but I run off of battery for a couple hours whenever the battery is fully charged (then repeat). I did not do this with my original battery (used it plugged in and fully charged all the time) and its now practically useless. Since I've done the constant unplugging/plugging procedure with the new battery, its retained its capacity nicely for much longer than the original.

npeterh · Oct 4, 2006, 11:45 PM

Thanks, so I take it the consensus is to leave the battery in even when I am plugged in. As long as I run down the battery every now and then it should be fine.

Peter

brokenjago · Oct 4, 2006, 11:55 PM

Originally Posted by jwall

Sorry... I can't believe I did that, especially after reading the excellent spelling lesson provided by chabig.

No big deal. It happens to all of us.

Simon · Oct 5, 2006, 02:54 AM

Originally Posted by ibook_steve

Leave the battery in, except for storage. Some Powerbooks run in reduced speed mode if the battery is not installed while running off of AC.

Steve is right. If you have a MBP or a PB that lowers the clock if the battery is removed, you don't really want to remove it, even if you're on AC power. Instead just make sure you drain the battery all the way down every once in a while and fully recharge it. This 'cycling' will help keep the capacity up.

But in the end keep in mind that no matter how much you care about your battery, no matter how well you treat it and even if you follow every guideline ever written for Li ion batteries, the battery capacity will decrease with time - its (useful) lifetime is finite. You can prolong that time, but in any event the battery will eventually become useless (near zero capacity).

To check your battery capacity, open /Applications/Utilities/SystemProfiler and go to Hardware -> Power -> Battery Information.

pokeman · 04:28 PM

THREAD REVIVAL

I'm wondering about how the battery is used when the notebook is used plugged in with a power cord at all times. Could anyone clarify this for me?

Does the computer get its power directly from the power cord, bypassing the battery, with any drop in battery charge simply the result of sitting idle

or

Does the computer still get its power from the battery, with the battery being partially drained and topped up at regular intervals.

Thanks

danengel · Nov 25, 2006, 05:41 PM

Does the computer get its power directly from the power cord, bypassing the battery, with any drop in battery charge simply the result of sitting idle

I'm not 100% sure, but that seems reasonable because the battery may be broken and you still want to run your notebook.

Although I've heard of submarines with a diesel generator to charge a battery, and then electrical motors running off this battery

ghporter · Nov 25, 2006, 06:05 PM

Macs are pretty smart machines. From what I've seen, they will top off the battery and then run exclusively from AC power while plugged in. Running with a defective battery may give you different indications, but a good battery gets full and then the machine runs on AC power.

Diesel submarines were very common-instead of having two different mechanisms to turn the propellers, they simply charged the batteries with the diesel engines. Diesel locomotives are electric too-the diesel engine runs a HUGE generator (or alternator, I'm not sure which) that provides the power to the ELECTRIC motors that move the locomotive.

imitchellg5 · Nov 25, 2006, 06:26 PM

Originally Posted by chabig

"lose" it.

Think of the words that have two o's. They all sound the same...

caboose
goose
moose
foose (as in fooseball)
noose
loose

Then there is lose (pronounced Luze)

What the heck did that have to do with anything?

pokeman · Nov 25, 2006, 07:08 PM

Thanks, guys. That does seem like the best way to do things and I'm pretty confident that the engineers will have made it that way.

wings_rfs · Nov 25, 2006, 08:35 PM

It's interesting to see all the misconceptions about battery care. Especially the one about having to discharge the battery periodically to extend its life. You're only allowed so many charge/discharge cycles, so the more you use the less you have left. It's as simple as that. The ONLY reason to EVER intentionally do this is to recalibrate the battery fuel guage. And even with a fuel gauge that's way out of calibration, the only side effect of that is it will report an incorrect number of minutes remaining. Key word is 'report' - it will still run your laptop until the voltage reaches its cutoff value. An excellant article on battery care is here:
How to prolong lithium-based batteries
All battery expert wanna-bes should read it.

ghporter · Nov 25, 2006, 09:04 PM

Originally Posted by wings_rfs

All battery expert wanna-bes should read it.

With this sort of statement, you should name names... I don't think you'll find anything that I've posted to be too wide of the mark. And a blanket statement like yours ADDS confusion. If you think Joe Member said something that's incorrect, say so. If you think we're all full of crap, say that too.

You are correct that there is a ton of "wrong facts" out there concerning batteries in general, and LiIon batteries more than others.

brokenjago recommended cycling LiIon batteries per Apple's suggestion. This is the ONLY potentially controversial thing I've seen in the thread, AND IT'S WHAT APPLE TELLS THE USER TO DO.

imitchellg5, look ALL the way to the beginning of the thread- someone had typed "loose" instead of "lose" when talking about a battery's capacity being diminished. And it was apparently one of chabig's pet peeves.

dcpc · Nov 25, 2006, 11:38 PM

Nobody has cited one important reason to keep the battery in at all times: accidental disconnection of the powercord. This is quite easy with the magnetic plug. If the battery is not in place you risk losing open work.

The battery should be good for 500 cycles. I have had my MB Pro for almost 4 weeks and the battery cycle count is 3. My laptop is almost always on the powercord and has not been powered down since I received it. In short, I expect to have about 40 cycles per year on the battery. Who cares about the battery?

ONG · Nov 26, 2006, 03:15 AM

read that link wing provided.... then i realized at the end that the person who wrote it is Isidor. he's a battery expert... owns Cadex which is a pretty large company that specializes in battery charging and analysis. let's just say he knows his batteries very well.

osiris · Nov 26, 2006, 03:35 AM

Originally Posted by dcpc

Nobody has cited one important reason to keep the battery in at all times: accidental disconnection of the powercord. This is quite easy with the magnetic plug. If the battery is not in place you risk losing open work.

The battery should be good for 500 cycles. I have had my MB Pro for almost 4 weeks and the battery cycle count is 3. My laptop is almost always on the powercord and has not been powered down since I received it. In short, I expect to have about 40 cycles per year on the battery. Who cares about the battery?

Geez, I'm on cycle 28 and it's only been 3 weeks. I travel around a bit, so removing the battery isn't an option.

mangacool · Nov 26, 2006, 01:08 PM

Back when Apple laptops used NiMH batteries I used to have the battery fail after about 3 years. The new Lithium Ion batteries (in use since the Titanium G4) I've never had a battery lose capacity or fail, and I keep laptops an average of 3 years.

Here's what I do to the batteries: Extended times hooked up to AC power, left overnight in sleep mode, transported in sleep mode, and occasionally running off battery for several hours. NiMH couldn't take that abuse but newer batteries love it (I even have an iPod I abuse the same way and its battery still has full capacity).

As for the power cord state and whether to remove the battery: Why would you buy a UPS for your desktop computer, that costs the same as a laptop battery, incidentally, and then put your laptop at risk by running it only on AC power?

The power circuit in Apple laptops works kind of like a UPS only different. It runs primarily off battery power but uses the power from the AC adapter to supplement the battery current. Now this is different from running off battery all the time! It measures the power coming from the cord and if the voltage is sufficient to run the whole laptop it stops drawing from the battery. This variable system allows it to switch very quickly to battery without the split-second delay that UPS has (the delay is actually reversed - AC power takes a half second to measure before the laptop switches over to AC), and also allows the laptop to be able to run with an AC adapter supplying insufficient power by siphoning power from the battery at high demand.

It also has a secondary "switch" so if the AC power adapter is providing more power than the laptop needs the excess is used to charge the battery if needed.

If you remove the battery the laptop's processor *may* go into low power mode but probably not. It does so if for some reason the AC adapter isn't providing enough power for maximum power usage, a condition where the laptop would draw some power from the battery (which isn't there) to make up the difference.

masugu · Nov 26, 2006, 02:09 PM

Originally Posted by imitchellg5

What the heck did that have to do with anything?

Agree, but it was a helpful lesson "irregardless" - ooooh, my other personal pet instance of word-misuse!!

teacher24_70 · Nov 27, 2006, 01:10 AM

How can you tell what cycle your battery is on?

Originally Posted by osiris

Geez, I'm on cycle 28 and it's only been 3 weeks. I travel around a bit, so removing the battery isn't an option.

skyman · Nov 27, 2006, 01:17 AM

Originally Posted by brokenjago

That's the second time in an hour I've seen that exact correction on these forums today.

It's funny but I too catch myself misspelling that blasted word all the time. It's like when a song gets stuck in your head. Well, lose and loose are stuck in there real good!

skyman · Nov 27, 2006, 01:20 AM

I can't tell you how many times the battery has saved my a$$ during a power failure. It's worth it's weight in gold!!

ONG · Nov 27, 2006, 03:29 AM

Originally Posted by teacher24_70

How can you tell what cycle your battery is on?

"Profile" maybe?

teacher24_70 · Nov 27, 2006, 04:16 AM

I couldn't find anything in "Profile" that showed the number of battery cycles--or ANYTHING about the battery.

Originally Posted by ONG

"Profile" maybe?

Simon · Nov 27, 2006, 06:16 AM

About This Mac > More Info... > Power > Cycle Count

Simon · Nov 27, 2006, 06:45 AM

Or if you prefer getting it with the CLI:

ioreg -l | grep -i LegacyBatteryInfo

osiris · Nov 27, 2006, 10:18 AM

Originally Posted by teacher24_70

How can you tell what cycle your battery is on?

I use the widget 'iStat'. But the other ways are good too!

urzsite · Nov 27, 2006, 11:28 AM

Confirmed with 4 Macbook's without battery = 1Ghz mode. (Tested with Geekbench, and the CPU benchmark is 50% off the normal value if the battery was inserted).

neilw · Nov 27, 2006, 04:33 PM

Another issue here is whether you want to be a slave to your battery, or just live your life already. To me, the inconvenience of removing a laptop battery when running off power would be pretty ridiculous, to say nothing of the wear and tear on the battery contacts and the loss of UPS-functionality of the battery.

For what it's worth, my Dell machine here at work spends 99% of it's time running in the docking station, and its battery still seems to be fine after 2.5 years.

tooki · Nov 27, 2006, 05:02 PM

Originally Posted by mangacool

Back when Apple laptops used NiMH batteries I used to have the battery fail after about 3 years. The new Lithium Ion batteries (in use since the Titanium G4) I've never had a battery lose capacity or fail, and I keep laptops an average of 3 years.

Actually, Apple has used Lithium Ion since the PowerBook 3400 from February 1997.

Regardless, early LiIon batteries fared really well. My Pismo's batteries lasted 5 years before dying, and I don't think I lost capacity until the third year of use.

Newer batteries aren't so good in the long term. My aluminum PowerBook G4's batteries lost 1/2 their capacity by year two. Both of them. One of the batteries died completely at age 2 1/2, and the other gives me a whopping hour of life now, at age 3. Color me not impressed.

tooki

amazing · Nov 28, 2006, 01:12 PM

With a magsafe connector that disconnects easily by design, best to leave the battery in. Unless you enjoy losing stuff? Aggravation and loss of productivity measured against the price of a replacement battery down the road?

stefanicotine · Nov 28, 2006, 01:51 PM

If your battery dies before the warranty expires, will it be replaced? It seems like a questionable thing to replace.

teacher24_70 · Nov 28, 2006, 04:33 PM

My Powerbook G4 (running 10.3.9) doesn't have a "Power" section under "About This Mac>More Info. . .".

I have:
Hardware (Memory, PCI/AGP Cards, ATA, SCSI, USB, FireWire, AirPort Card, Modems)
Software (Applications, Extensions)
Network
Logs

If I chose Extended Report under "View", then I also get "Frameworks" under Software.

Nothing about Power. Is it somewhere else under 10.3.9?

Originally Posted by Simon

About This Mac > More Info... > Power > Cycle Count

Simon · Nov 29, 2006, 04:10 AM

IIRC PPC Macs don't have it. Try this little command instead:

ioreg -l | grep -i IOBatteryInfo | head -n 1

stefanicotine · Nov 29, 2006, 04:17 AM

Originally Posted by stefanicotine

If your battery dies before the warranty expires, will it be replaced? It seems like a questionable thing to replace.

If anyone else was curious about this, your battery is covered up to one year. They consider 2 hours of battery life "degraded performance" and will replace it for free. If it's in the first 90 days, no questions asked. If it's after the 90 days, but within the first year, they will make you calibrate your battery and report back before they make any replacements.

amazing · Nov 29, 2006, 11:15 AM

My 12" AlPB has a Power section in System Profiler under 10.4.8 and I'm at 171 cycles. It's right below Parallel SCSI and before Printers and Serial-ATA (and it doesn't take much guessing to figure out which of those mentioned above have "no information found.)

I think it's just that 10.4.8 offers more info than 10.3.9

teacher24_70 · Nov 29, 2006, 09:44 PM

I figured that it probably had something to do with the fact that I've not upgraded to Tiger yet. Someone else posted a command to try, but I'm a little leary of working in the Terminal. Maybe I'll feel gutsy and try it anyway.

Originally Posted by amazing

My 12" AlPB has a Power section in System Profiler under 10.4.8 and I'm at 171 cycles. It's right below Parallel SCSI and before Printers and Serial-ATA (and it doesn't take much guessing to figure out which of those mentioned above have "no information found.)

I think it's just that 10.4.8 offers more info than 10.3.9

amazing · Nov 29, 2006, 10:04 PM

For battery info, just download the free coconutbattery. It'll give you all the info you need.

teacher24_70 · Nov 29, 2006, 10:58 PM

I looked up the application on VersionTracker and it sounded great! I was getting excited and then saw that it only works with 10.4.4--which I don't have! Thus, the reason that I couldn't look it up under Profile to begin with.

Thanks, though! I'll file that application information away for when I upgrade.

Originally Posted by amazing

For battery info, just download the free coconutbattery. It'll give you all the info you need.

amazing · Nov 29, 2006, 11:10 PM

OOPS! Sorry about that! However, looks like you can try battorox which does work with 10.3.x

Battorox 1.8.2 - VersionTracker

tkmd · Nov 30, 2006, 12:33 AM

Take it from someone who's had laptops - charge the battery up then take it out! The batteries capacity will diminish after about 9 months of keeping it in.