[Andrej]

Alright so I am playing iTunes, browsing Firefox, and my total CPU usage is 7%.

4-core i7 2.2 GHz, solid drive, 10.7

I used to get 6-7 hours on a full charge. Now I can't get more than 5.

At 50%, I am seeing that I have only 1 hour and 45 minutes left. I used to get 2 hours and 30 minutes as of last month and 3 hours a month before that, with equivalent CPU usage. Not sure what's going on. Is it time to calibrate the battery (if so, which method do you recommend)?
Is there too much dust inside my computer, and what's the best way to clean it? I have canned air.


My display brightness is 6 out of 17.
My sound is off.
My LED keyboard lights are off.
I rarely let the battery go below 40%.
Usually I don't leave the power plugged in for more than 20 minutes at 100%.
I shut down my computer every night.
I've been guilty of letting the computer shut down with the battery at 90% a few times and not using it for a day.
I usually let the battery charge with the lid up if I'm at home so the screen doesn't get hot when the computer is asleep and charging.

Computer is also generally a little hotter overall, the fan is a little louder, especially upon charging.

[ibook_steve]

I'd be thrilled to get over 5 hours, as would most people. Maybe 10.7 has something to do with it. Others might be able to weigh in on this. I'm still on 10.6.8 with my 15" 2.66 i7 from last year.

But a few things:

1) You should test with the display brightness at 1 tick above off. Backlight has huge influence on battery use. You should also try turning off wifi (assuming you can use a wired connection) and bluetooth. Oh, and dust will have nothing whatsoever to do with battery life.
2) There is no reason to worry about leaving the machine plugged in at 100%. I can't imagine connecting and disconnecting power constantly throughout the day (every 20 minutes? Really?). This doesn't gain you anything other than additional micro-cycles on the battery.
3) There is zero reason to shut down every night. Why do you do this? Just close the lid and let it sleep. What a pain to boot every morning (though granted an SSD helps here).
4) "I've been guilty of letting the computer shut down with the battery at 90% a few times and not using it for a day." Congratulations, you're guilty. What's the big deal about doing this?
5) There is no need to charge with the screen up. Charging should not heat anything up, at least not to any dangerous degree, and the machine is designed to charge no matter what state it is in.

Basically, stop worrying about coddling your machine, and just use it however you want. I don't understand why people spend so much time worrying about things like this.

Steve

[Andrej]

No, I will keep worrying. How many times have you seen stories about people's battery life going from 5 hours, to 4 hours, to 3 hours, and then their battery craps out? My Powerbook went from 5 hours down to 2.5. My co-worker's Pro Macbook needed 2 battery replacements. So, I worry and for decent reason.

I don't use Bluetooth.

Actually, it's not worry... I want to know: Why, seriously, why is my performance being affected?

Really when I'm just browsing documents I used to be able to get 6-8 hours. But that's still awful, I think that computers should get at least 24 hours of battery life, I'm sick of having to plug this thing in everywhere I go at work!

Wait a minute, you get less battery life than I do, how do you manage to not need to keep plugging this thing in everywhere you go if you get less battery life than me?

There is **plenty** of reason to shut down the computer at night. Here's a list:
[1] It's a waste of power, this one should be obvious.
[2] Slower overall performance if you keep leaving your computer on all the time.
[3] It's more dangerous when in transfer, better to shut it off.
[4] Programs left running overnight may not function correctly, they may be download applications or something with time-sensitive nature.
[5] Higher probability of corruption with logs and preferences.
[6] Networking may not wake up properly.
Seriously, why would people waste their performance and battery life like this?

I want THE MOST out of my computer, so anything less means I'm doing something wrong, or didn't calibrate the battery properly the very first time (which I did... I think I had to wait something like 13 hours before shutdown). How come I can't get it back up to even half that? Something is very wrong.


"Congratulations, you're guilty. What's the big deal about doing this?"
Here's why: The big deal is that I have read that keeping your battery in your computer while not using your computer while the battery is at 100% will shorten its lifespan. They say to discharge it to 50%. So, I try to get close to (or somewhat above) 50% before I shut it down for the night. Doing this for a year should keep maximum performance extended. That's why.



But I think that I figured out the problem: while charging, the battery gets hot, which makes my desk hot, which makes the fan operate faster. So, even after I disconnect the power, the computer/desk are both still warm, and the fan runs more, which uses more battery power, which keeps the computer hot in the first place. This does not show up in Activity Monitor, so that's why I was getting a little lost, and I think that not having an ice bucket attached to the underside of my desk may be aggravating the problem. I think that having no AC in my room in the summer may also have something to do with it (not paying $200 each season per apartment policy, I'll suffer without it). But this is just a guess for me. How does it sound to you folks?

[Waragainstsleep]

Originally Posted by Andrej 

No, I will keep worrying. How many times have you seen stories about people's battery life going from 5 hours, to 4 hours, to 3 hours, and then their battery craps out? My Powerbook went from 5 hours down to 2.5. My co-worker's Pro Macbook needed 2 battery replacements. So, I worry and for decent reason.

No you don't. How many times have you seen people bother to comment that their battery (or anything else about the their computer) is working just fine? They don't bother, they only comment when they need to vent or complain or get help because something has gone wrong.

Originally Posted by Andrej 

Really when I'm just browsing documents I used to be able to get 6-8 hours. But that's still awful, I think that computers should get at least 24 hours of battery life, I'm sick of having to plug this thing in everywhere I go at work!

If you aren't happy with the state of the tech then either don't use it, or get a degree and do some research and make a discovery to improve it. Or wait for someone else to do it.

Originally Posted by Andrej 

There is **plenty** of reason to shut down the computer at night. Here's a list:
[1] It's a waste of power, this one should be obvious.
[2] Slower overall performance if you keep leaving your computer on all the time.
[3] It's more dangerous when in transfer, better to shut it off.
[4] Programs left running overnight may not function correctly, they may be download applications or something with time-sensitive nature.
[5] Higher probability of corruption with logs and preferences.
[6] Networking may not wake up properly.
Seriously, why would people waste their performance and battery life like this?

[1] Its a waste of very little power tbh. More than it used to be with PPC, but still not all that much.
[2] I hardly notice any difference and I leave my 2008 MBP weeks without rebooting. Also my HDD is a 640GB with about 3-5GB free.
[3] Not really true. Unless you plan on watering your laptop. HDD heads are parked during sleep.
[4] What? Who said leave it awake and running? Just put it to sleep. No programs will run while its sleeping.
[5] Not in my experience.
[6] Now you are just clutching at straws and making stuff up.

[QUOTE=Andrej;4102643]
"Congratulations, you're guilty. What's the big deal about doing this?"
Here's why: The big deal is that I have read that keeping your battery in your computer while not using your computer while the battery is at 100% will shorten its lifespan. They say to discharge it to 50%. So, I try to get close to (or somewhat above) 50% before I shut it down for the night. Doing this for a year should keep maximum performance extended. That's why.
[/QUOTE/

Apple does not recommend leaving portables plugged into AC all the time. This is only because they do recommend that the battery should be kept cycling to a certain extent. The example they give is to disconnect from AC in the morning, use the laptop on the way to work on a train then plug it back in when you get there. You clearly use yours frequently away from power sources so leaving it plugged in when there is one available should fit you in perfectly with Apple guidelines.

Apple - Batteries - Notebooks

The reason that many many people tell you not to leave your laptop charging is because of PC laptops. If you leave those on charge, they don't stop. They overcharge which kills the batteries quick. This is because the vast majority of them use cheap sh**ty batteries and cheaper sh****er chargers. Those same people bitch and moan or faint when you tell them the price of an Apple magsafe adaptor but the Apple systems stop charging when they get to 100%.


The bottom line is this: Use your machine however it suits you. If your battery isn't performing the way you think it should, take it to Apple and if they agree they will put a new one in for you. They can't tell much if anything about whether or not you are following best practices of battery care and the chances are they wouldn't bother to check if they could. The guidelines they get have expected battery life for each machine and if they go too far below that whilst under 1000 cycles then you get a new one. Its 300 cycles for the old Li-Ion batteries.

[ibook_steve]

Waragainstsleep's points are pretty much how I would have responded. As far as the heat being an issue, just raise your machine up! I always have mine on a Podium Coolpad (http://http://roadtools.com/) and it only gets hot when I'm doing something intensive (compiling a project or a game for example).

As to your other points, 4, 5, and 6 just don't make any sense. 1 is possible, but if you sleep the machine at night, everything is shut off except a small amount of power to auto-refresh the memory. 2 I've never noticed. I end up rebooting when I install updates every few weeks and I have no problems. For 3, as mentioned, the hard drive is parked (but you have an SSD so even this is not an issue). That's the whole point of sleep. I can't imagine taking the time to completely shut down before moving my machine between home and work everyday.

You have two people now saying you should just relax and use your machine normally. I'm sure others will chime in as well.

And I do plug in wherever I go, but it doesn't bother me. Why should it?

Steve

[Andrej]

Well that's the advice that I kept seeing when I was a member at MacRumors for 3 years.
You folks have some very different suggestions.

[Waragainstsleep]

I probably could have been a bit friendlier with my answers. Sorry about that.