Battery

Vinny · Nov 12, 2008

istat dashboard widget will tell you battery status

wxman2003 · Nov 12, 2008

iLaw said:
I don't think that is correct. There is no reason why the laptop would perform at a lower level when connected to a consistent AC power source.

From experience, the Laptop will consider you on AC power (whether or not the battery is present) and maximize the performance of your notebook because it doesn't have to worry about preserving battery life.

If you have proof to the contrary, I'd love to see it, please.

Right from the apple web site. Top line under Summary.

MacBook and MacBook Pro: Mac reduces processor speed when battery is removed while operating from an A/C adaptor

kipo said:
Wow you seem the perfect person to ask this....how exactly do you know your battery status i.e. how many cycles your battery has done etc..?

Click on "About this Mac" by clicking the apple logo. Then click on "more info" and then click on power. It will tell you your cycle count, battery status, etc.

krepta · Nov 13, 2008

wxman2003 said:
Right from the apple web site. Top line under Summary.

MacBook and MacBook Pro: Mac reduces processor speed when battery is removed while operating from an A/C adaptor

So they're saying the battery provides more power than the a/c? Does that make sense? Considering the a/c provides up to 120 volts and according to my "About This Mac" the battery only puts out 12. I guess the adapter could be reducing it to below 12, but why would they do that? Unless they want to sell more batteries...

Besides, I had to run it with no battery once before and didn't notice any slow downs. How about you, kipo? You said you were doing it too right?

and now i don't trust the apple articles, because I just found two articles, both dated 2008. One says to store an unused battery at 50% charge. The other says to store it at 100% charge. So...

But the idea to run it off the a/c with no battery was to prolong battery life. According to Apple, after 300 cycles a battery is expected to have 80% its original capacity. I read the original capacity is 5200 mAh (whatever that is). And according to my macbook, I have a capacity of 5101 mAh (98%) after 755 cycles! so I guess if it aint broke, don't fix it. and it's not worth the risk of losing unsaved work.

For those who might want to know, I usually run it down till the warning box pops up (about 10min/7% left), then charge it all the way to 100. In other words, "deep cycling" which someone said was bad. Maybe I'm just lucky. The battery's 1 year and 9 months old (original) and lasts between 2 1/2 to over 4 hours, depending on what i'm doing. (If I'm right that mAh stands for milli-Amperage-hours, then that means it should last 5 hours)

To answer the original question, I never leave it plugged in (on purpose) after reaches 100%.

And 1 cycle, according to Apple, is using a full charge, regardless of when you recharge. So if you use up 1/2 battery, recharge, 1/4, recharge, then another 1/4, that would be one cycle, not 3 like i thought.

wxman2003 · Nov 13, 2008

All you wanted to know about batteries, and probably more than anyone cares.

Resources for laptop battery charger, cheap laptop batteries etc.

zackplanet42 · Nov 13, 2008

krepta said:
and now i don't trust the apple articles, because I just found two articles, both dated 2008. One says to store an unused battery at 50% charge. The other says to store it at 100% charge. So...

But the idea to run it off the a/c with no battery was to prolong battery life. According to Apple, after 300 cycles a battery is expected to have 80% its original capacity. I read the original capacity is 5200 mAh (whatever that is). And according to my macbook, I have a capacity of 5101 mAh (98%) after 755 cycles! so I guess if it aint broke, don't fix it. and it's not worth the risk of losing unsaved work.

For those who might want to know, I usually run it down till the warning box pops up (about 10min/7% left), then charge it all the way to 100. In other words, "deep cycling" which someone said was bad. Maybe I'm just lucky. The battery's 1 year and 9 months old (original) and lasts between 2 1/2 to over 4 hours, depending on what i'm doing. (If I'm right that mAh stands for milli-Amperage-hours, then that means it should last 5 hours)

To answer the original question, I never leave it plugged in (on purpose) after reaches 100%.

And 1 cycle, according to Apple, is using a full charge, regardless of when you recharge. So if you use up 1/2 battery, recharge, 1/4, recharge, then another 1/4, that would be one cycle, not 3 like i thought.

mAH stands for milliamp hour or the max amperage it will supply for one hour

Wiss · Nov 14, 2008

ok, so today my battery decided that it won't charge itself to 100%?
I've seen 97% (charging) stuck on the screen for the entire night I left it charging....

i'm going to try to use up the battery and recharge... will update you all later

ok... nevermind... came across this on apple support. sorry i'm still new to mac!
Apple Portables: Battery may not show a full charge in Mac OS X

Resolution
This is normal. The batteries used in these computers are designed to avoid short discharge/charge cycles in order to prolong the overall life of the battery.

When setting the Mac OS X battery status menu bar icon to display charge state by percentage, you may notice that the reported charge stays between 93 or 95 percent and 99 percent.

To allow the adapter to recharge the battery to 100%, simply allow the charge to drop below 93%. The adapter will automatically recharge the battery to 100%.

krepta · Nov 18, 2008

ok, so now the question: when it's holding steady at 97%, does that mean it is bypassing the battery completely in order to avoid short charge cycles? (because that would mean leaving it plugged in would cause no harm, n'est-ce pas?)

jayfredem · Nov 18, 2008

How long can a Macbook go on a full charge if left asleep? Or conversely how much charge does it use per hour, for instance. i want to know if I can leave it on in sleep mode without switching off as I use at least once every two days.

krepta · Nov 19, 2008

considering when the battery reaches very low charge, it is designed to go into sleep mode at that point, it should last a very long time in sleep off a full charge. I'm sure I've left it in sleep for more than two days on less than a full charge. I also know a lot of people don't even bother to turn it off at all.

And i THINK, at some point it saves memory to hard drive, so even if it loses power you'll be okay.

purplewithenvy · Nov 20, 2008

I'm new to mac's and am not the most technological savvy gal. Is it better to constantly have your battery plugged in, or let it drain pretty much every day, every other day, every week, etc?

axis42 · Dec 10, 2008

Obviously there is not much agreement here, eh? too bad cause I want to see my battery last as long as possible since disposing of them is terrible for the environment and replacing them is pricey... I'll try and post with info as I find it too. Maybe we can find someone, somewhere that's done some controlled testing? Imagine that: empirical evidence ;P

One question though: I have read on this thread about "calibrating" one's battery. what is this and how is it done? When should it be done?

Whoops. That's three questions.

Thanks,
c

5point9limited · Dec 11, 2008

krepta said:
and now i don't trust the apple articles, because I just found two articles, both dated 2008. One says to store an unused battery at 50% charge. The other says to store it at 100% charge. So...

But the idea to run it off the a/c with no battery was to prolong battery life. According to Apple, after 300 cycles a battery is expected to have 80% its original capacity. I read the original capacity is 5200 mAh (whatever that is). And according to my macbook, I have a capacity of 5101 mAh (98%) after 755 cycles! so I guess if it aint broke, don't fix it. and it's not worth the risk of losing unsaved work.

For those who might want to know, I usually run it down till the warning box pops up (about 10min/7% left), then charge it all the way to 100. In other words, "deep cycling" which someone said was bad. Maybe I'm just lucky. The battery's 1 year and 9 months old (original) and lasts between 2 1/2 to over 4 hours, depending on what i'm doing. (If I'm right that mAh stands for milli-Amperage-hours, then that means it should last 5 hours)

To answer the original question, I never leave it plugged in (on purpose) after reaches 100%.

And 1 cycle, according to Apple, is using a full charge, regardless of when you recharge. So if you use up 1/2 battery, recharge, 1/4, recharge, then another 1/4, that would be one cycle, not 3 like i thought.

My cycle count is at 280 since 11/25/2007

The mAh is at 4940

I let my battery drain FULLY every time I charge. When I do charge, I usually turn the computer off (80-90% of the time) and let it charge nice and cool (temperature). The 10min warning has to pop up in order for me to plug it in.

The battery lasts from 3-4 hrs depending on what I am doing.

It does seem to have degraded in performance since the 1st day, but not too much, maybe a half hr to 45min difference. I am pretty impressed.

I use this method with all of my electronics (iPod, Jawbone Bluetooth, electric razors, etc.) All seem to have excellent battery life and I won't change my habits.

I definitely want to know more about the charging practices.

GIVE YOUR STATS and CHARGING HABITS!

krepta · Dec 11, 2008

Calibrating:
tkim posted this link earlier: Calibrating your computer's battery for best performance

to 5point9limited, are you not concerned that your cycle count has not changed in over a year?? Shouldn't it be counting?

5point9limited · Dec 11, 2008

krepta said:
Calibrating:
tkim posted this link earlier: Calibrating your computer's battery for best performance

to 5point9limited, are you not concerned that your cycle count has not changed in over a year?? Shouldn't it be counting?

Haha, thats how many times it has cycled in the year I have had it. No concerns.

rybka007 · Dec 12, 2008

Hi ,I have a huge problem with my new aluminum macbook. The battery is running out really fast. Right now I have 80%, the keybord backlight is switched off, the display brightness is set to minimum, I am only using safari and wifi and mac tells me that I have 2:43 more... Normally people write that their new laptop lasts 4-5 hours. Coconut battery tells me that the original battery capacity was 4100 and now it is 4089. My macbook has only two days.

istat at the begining was showing 4200, now it is 4108... is it normal?

5point9limited · Dec 12, 2008

rybka007 said:
Hi ,I have a huge problem with my new aluminum macbook. The battery is running out really fast. Right now I have 80%, the keybord backlight is switched off, the display brightness is set to minimum, I am only using safari and wifi and mac tells me that I have 2:43 more... Normally people write that their new laptop lasts 4-5 hours. Coconut battery tells me that the original battery capacity was 4100 and now it is 4089. My macbook has only two days.

istat at the begining was showing 4200, now it is 4108... is it normal?

Try to drain it all the way down, shut it down, then charge it fully. Then look at your stats.

I have 2 new MacBook Aluminums here, When I get a chance, I'll post up what their batteries are running at.

rybka007 · Dec 13, 2008

I've done it once. After that capacity increased by 20, but several hours later it was down by 100... The istat shows 100% health...