results of simple battery test

Today I conducted a simple battery test for my March 2009 MBP (my signature line has the specs). This is not the new irremovable battery MBP. I can remove my battery and have a second battery to use when needed.

I ran the machine in "Better Battery Life" mode set by going to Energy Saver in System Preferences. With only Safari running I surfed the Internet for an hour, starting at a full 100% charge at 11:30 am.

I noticed that, without fail, I lost 1% of battery charge every 2 minutes.

At 12 noon I had lost 15% of charge (I was down to 85%). At this rate I will loose all charge in 200 minutes (3 hours and 20 minutes).

Wow!! This is not good! Imagine if I was using iMovie, GarageBand, iPhoto, or had my Parallels WinXP running. My charge wouldn't last at all.

I would like someone who has the same graphics card as mine in a MBP 15 inch but has the newer irremovable battery to conduct the same test I did, reporting your results as I did. Thanks!!

Doing "individual" battery tests is fun...but you can't expect someone else to do your test & get the same results.

You didn't mention:

- what your screen brightness was
- was bluetooth on or off?
- if your illuminated keyboard backlighting was on (I assume you have this)
- what websites you went to. Playing videos via You-Tube is not the same as posting messages on an internet forum...and everything in between.
- also, not all batteries are the same. Batteries lose capacity over time. So your MBP 15" battery may have more or less battery capacity left than someone else's 15" MBP.

There are lots & lots of different factors that go into a battery life test...it really isn't that simple.

- Nick

How right you are!!! Please forgive my simplicity!! I never thought about the factors you mentioned. For the record:
- brightness was at full blast
- bluetooth was on
- illuminated keyboard backlighting was on
- spent the whole 30 minutes surfing around MacForums only
- my machine is new, purchased in June 2009 (I opted not to buy June 2009 model), therefore my battery still should have original capacity

I imagine if bluetooth and keyboard were off along with a lower brightness setting I would have gotten better results. I will try testing again. Anyone interested in the results? Or should I take my simple azz away? LOL.

And if u r keen on comparing apples with apples then use ethernet not wireless and make sure peripherals are out of the test.

coolbreeze said:

I imagine if bluetooth and keyboard were off along with a lower brightness setting I would have gotten better results. I will try testing again. Anyone interested in the results? Or should I take my simple azz away? LOL.

Click to expand...

I would be interested...because it would at least be a comparison on your computer before & after the changes....and give the rest of us an idea of just how much display brightness impacts battery life (as well as the other stuff).

Max brightness seems pretty extreme if you were indoors (maybe not if outdoors)...especially for a battery "run time" test.

Give it a go...I would like to see the new numbers!

- Nick

Ok I just ran the test again.

- Better Battery life selected
- brightness slider was placed exactly halfway
- bluetooth was off
- illuminated keyboard backlighting was off
- spent the whole 30 minutes surfing around MacForums only
- Time Machine was off (was off during the 1st test)
- No peripherals attached (none were attached during 1st test)
- my machine is new, purchased in June 2009 (I opted not to buy June 2009 model), therefore my battery still should have original capacity

I started at 9:25 with 100% charge and at 9:55 I had lost exactly 10% charge, down to 90%. It was exact.

This means I lost 1% charge every 3 minutes compared to loosing 1% charge every 2 minutes in the first test.

In the first test I would have lost all charge in 200 minutes (3 hours and 20 minutes). In the second test I would loose all charge in 300 minutes (exactly 5 hours).

I did not make these numbers up nor did I round. They just came out exact.

When I purchased this notebook the salesman did say my battery would last 5 hours without charging. He didn't say you would have to be doing very little to achieve the 5 hours with no charge.

Anyway, I'm satisfied. I was only curious. Anyone with an irremovable battery experiencing battery power without charge for 7 hours as advertised?

coolbreeze said:

When I purchased this notebook the salesman did say my battery would last 5 hours without charging. He didn't say you would have to be doing very little to achieve the 5 hours with no charge.

Anyway, I'm satisfied. I was only curious. Anyone with an irremovable battery experiencing battery power without charge for 7 hours as advertised?

Click to expand...

Coolbreeze,

Thanks for redoing your battery test...and as you see you had a significant improvement.

Now to comment on what you said about the salesman & battery life.

EVERY computer manufacturer of laptops when determining battery runtime (hours & minutes)...does it under the most favorable of conditions...similar to what you did the second time.

This is the way it has always been since the first Mac laptops came out in 1989 (20 YEARS AGO)...and that's the way it is today! Nothing has changed, so you really should not be surprised!

Under "real" world conditions...conditions that most of us use our laptops...you more than likely will not get a 5 hour battery life!

Did you really think that you could hop on a plane, fly from New York to LA (about a 5.5 hour trip) and be able to watch DVD's for 5 hours before the battery went dead!!! No way!!! Try watching some DVD's in your laptop...and you'll find you will probably get around 2-2.5 hours.

I'm really surprised that you didn't know that the battery times manufacturers communicate are done under very favorable conditions to maximize battery life.

This really applies to almost any consumer product. The manufacturer wants to communicate the BEST possible message to get customers to buy their products.

This applies to:

- automobile gas mileage
- how well cold medicines work
- how strong paper towels are
- how cool you will be if you buy our sneakers
- how using our product will get you lots of "hot chicks" (you ever see those AXE body product commercials)
- and of course laptop companies & their battery life claims!!!

Thanks again for rerunning your test, and posting the results,

- Nick

pigoo3,

Yea I knew manufacturers always communicate the best possible message. But Apple is not your average company. They have a reputation for better customer treatment. However, I'm not complaining. I am satisfied.

Next I will completely drain my battery and see how long it takes to charge while completely shut-down vs. while in use. I am curious and think others might be too.

I noticed that you are knowledgeable and give great advice in many areas in this forum. Thanks for helping. I have used the advice you give on more than one occasion.

coolbreeze said:

pigoo3,

Yea I knew manufacturers always communicate the best possible message. But Apple is not your average company. They have a reputation for better customer treatment. However, I'm not complaining. I am satisfied.

Next I will completely drain my battery and see how long it takes to charge while completely shut-down vs. while in use. I am curious and think others might be too.

I noticed that you are knowledgeable and give great advice in many areas in this forum. Thanks for helping. I have used the advice you give on more than one occasion.

Click to expand...

Yes I agree that Apple does seem to be above average or even well above average when it comes to reputation & customer service.

But Apple still employ's Marketing people...and Marketing people will take the smallest little positive message and EXPLODE it into some sort of "monumental success".

For example...like taking the improvement of 2 extra minutes of battery life...and turning it into a message that you would think would be as innovative as finding the cure for cancer!!! I'm exaggerating of course...but you get the idea.

So when it comes to battery life claims...I think to some degree at least, Apple suffers from the same faults as other computer manufacturers...in that their laptop battery life claims are very optimistic...and in many ways don't represent what the average laptop user should expect when unplugged.

And Apple does have competition. If a competitor is claiming 7 hours of battery life (under very very optimistic or unreal conditions), and if Apple was claiming 3.5 hours of battery life under much more realistic conditions...the average consumer will see in this example that Apple only has 50% of the battery life and thus may not purchase Apple laptops...since the average laptop consumer will not "dig" deep enough into the details to understand the reasons for the difference. So Apple has to do what other laptop manufacturers do...and that is advertise battery life claims that are on the optimistic side.

Just a "guesstimate" on my part...but when ever I see laptop battery claims...I usually subtract at least 25% from the claim for a more accurate estimate of what I will get from a single battery charge.

Obviously different folks will get differing battery life results. Someone playing graphics intensive games, with screen brightness & sound volume turned up, or someone watching DVD's...will experience MUCH shorter battery runtime on a single charge, than someone working on a word processing document with screen brightness turned way down, and bluetooth & airport turned off.

Have fun running those battery life tests. They can be very interesting & informative! Maybe you will stumble across some sort of battery life saving secret...that the rest of us have missed!

- Nick