Lies, Damn Lies, and Battery-Life Statistics

theodp writes "What if automakers measured gas mileage by rolling their cars downhill with their engines idling? They might, Newsweek's Daniel Lyons suggests, if they took inspiration from the MobileMark 2007 notebook battery-life benchmark test, the creation of a consortium called BAPCo, whose members are — surprise — computer makers and other tech companies. Laptops score big numbers, Lyons explains, because they're tested with screens dimmed to 20%-30% of full brightness, Wi-Fi turned off, and the main processor chip running at 7.5% of capacity. Professional reviewers see company-generated battery-life claims as a joke. 'The rule of thumb is that in real-world use you get about 50 percent of rated battery life,' says a Gizmodo associate editor. Leading the call for reform is the not-necessarily-altruistic AMD, who gripes that MM07 was created in Intel's labs and rigged so Intel chips would outscore AMD chips, which draw more power when idle."

Comments

Who did this study?

[Anonymous Coward]

Captain Obvious?

gas mialage

[He who knows]

They would need a really big hill.

Apple Don't

[Space cowboy]

Take a look at Anandtech's MBP review. The tagline 'Battery life to die for' sort of gives away the tale though.

Apple claim 5-8 hours. Anand got 4.92 (heavy downloading + XVid + Web browsing) to 8.13 hours (Wireless web browsing) with the screen at half-brightness ("completely useable") and no funny optimisations.

Maybe, just maybe, there's something to this "our batteries are better" thing they've got going; if someone comes out with a spare-battery-attached-to-a-magsafe-connector for those die-hards who absolutely *need* it, angels may sing in the treetops. Personally I've never needed to change the battery in my portable (whatever portable I've had) so it's no big deal to me. Yadda yadda, one datapoint not a trend...

Simon.

Re:Apple Don't

[wnknisely]

For what it's worth, I'm seeing numbers comparable to these on my new Macbook pro. Perhaps Apple is using a different benchmark than the one in the article above?

Re:Apple Don't

[arminw]

...Perhaps Apple is using a different benchmark...

Perhaps Apple computers are able to manage power better because Apple is the only computer maker that engineers their hardware and software together and is thus able to optimize battery life.

Re:Apple Don't

[speculatrix]

there's no point in ordering a *spare* battery when you buy a laptop; ordering a *second* battery because you're travelling a lot might make sense. this is because LiIon batteries age, and you can only slow down the ageing by keeping them 40% charged in a moderately cool place.

LiIon batteries also lose capacity after a number of charge/discharge cycles, the number varies according to how deep the cycles are and the temperatures you reach in the process. When the battery packs are particularly expensive - think Prius and other electric cars - the battery management electronics are crucial to protecting the investment, and the batteries are never run anywhere near flat and particularly are never fully charge to prevent some cells overcharging, and the charge/discharge controlled carefully to prevent temperature rises leading to premature ageing.

thus, in conclusion, keep your laptop battery cool, don't thrash its battery, don't deep cycle it, buy a good brand so you can buy a new battery *in*the*future*not*for*storage*.

Re:Apple Don't

[moosesocks]

All of these things are true for Lithium Ion batteries.

However, Apple's current line of notebooks use Lithium Polymer instead of Lithium Ion. Additionally, the charging circuitry is supposedly much more sophisticated.

I'm not sure if the modes of failure for commerical Li-Pol packs are well-known at this point, and I have no reason to believe that they'd be the same as those for Li-Ion.

Hate to sound like a Mac whore

[twistedcubic]

but I get five hours of battery life on a Macbook (last year's model), so I think Apple doesn't lie about its stats (because they don't have to?). Despite all the claims that Macs are overpriced, I think these are among the cheapest non-netbooks you can get with great battery life. IMO, laptops which last only 2.5 hours on a battery should not be sold.

Re:Hate to sound like a Mac whore

[OrangeTide]

I got my Macbook because it makes a pretty decent Linux box (although I now dual-boot OSX because Apple has slowly wormed its way into my life), and the lowest end Macbook is pretty affordable. Comparable in price and specs to a mid-range laptop. And yes it does get good battery life (the battery life is better in OSX than in Linux though)

If you use computers the way I do, the you can really get those 4 hours that those cheap PC laptops claim. I use it in the dark(so screen dimmed), no WiFi, command-line only running a text editor for Vi. Occasionally kicking on the CPU to compile a .c to a .o and link the .o's (using 'make' saves a tremendous amount of battery life). My Macbook got a little over 5.5 hours for me on a flight before it had to shut down(just writing code and reading man pages). If I would have sprung for the Macbook Pro it would have been more like 7-8 hours though.

Re:Does anyone pay attention to battery life anymo

[sznupi]

People "expect" that just because they don't really realize it can be better. Put it another way: they don't expect that at all, they just accept it.

Re:Does anyone pay attention to battery life anymo

[Anonymous Coward]

2.5 hours? Really? What's the point? My two and a half year old Thinkpad T60 gets 5 hours on a bad day. My friend with a similarly spec'd Thinkpad (a bit older) claims to have gotten 9 hours with wifi off and more like 7 hours in reasonable usage (his is tweaked a bit better). Both of us have just the extended battery (there is also space for a second, smaller battery instead of an optical drive).

I don't trust Apple's sealed-in batteries

[argent]

I will never buy a laptop with a non-removable battery even if it gets 8 hours playing MMOs at full resolution. I *have* a Macbook Pro, and if it had an "iBattery" my laptop would have been destroyed when the battery failed and swelled... instead of having the battery pop safely out of its compartment.

Better battery, great, but I'll take a laptop that's a millimeter thicker if that's what it takes to put a door on the battery compartment.

Already have that

[SuperKendall]

If someone comes out with a spare-battery-attached-to-a-magsafe-connector for those die-hards who absolutely *need* it, angels may sing in the treetops

This is exactly why I don't understand the fuss over non-removable batteries. You get better battery life, and if you need extra power you've always been able to buy external battery packs. They have cable that attach to the Magsafe connector. You can get them in a range of sizes, including sizes that are not much larger than a spare battery would have been anyway...

Similarly there are tons of external packs for smaller devices like the iPhone/iPod (or anything usb charged).

I also have not often found the need for an second battery in a laptop if I can get at least three to four hours out of it. Basically the only time is an international flight, and for that the external batteries are perfect. Heck, until it broke the Solio solar powered recharger I had could even recharge itself in-flight as long as I was at a window!!

Standards

[fermion]

As long as everyone is using the same standard, it is not that big of a problem. If we go before cars, to horses, we can see why this is. The story is that James Watt used the term horsepower to market the steam engine, for instance, the ROI might be related to the number of horses you did not have to maintain. The story also is that he did not make his horses work very hard. As today, the ROI was well overstated, but as the relationship became less about horse and more about steam engines, the standard became more useful.

We saw the same issue with clock cycles. People misinterpreted, and the marketing drones were more than happy to let them do so, clocking as measure of work. A faster processor did not mean that more work would get done, but the consumer did not know that, so they would pay more for fantasy benefits.

In terms of fuel consumption, and battery life, the reality is more of the horsepower that the gigahertz. As long as one is running comparable tests, then one can assume that a car rated at 20 mpg will run longer than a car rated at 10 mpg, just like a computer that is rated for 4 hours will run longer than a computer rated at 2 hours. The problem, like the horse, is related the terms horse, hour, and mpg to actual physical quantities. We know that the physical performance is actual 20% or so less in real life.

As mentioned elsewhere, what messes life up is companies like Apple that advertise 3 hours of battery life, and, under normal use, actually get it.

Re:A Challenege For AMD

[Celeste R]

This challenge can be equally turned around.

For the sake of devil's advocacy:

Hey Intel, I have a challenge for you. Instead of rigging your battery life testing mechanisms, why not run your tests like real-world usage would do?

Also, frankly, I don't want a laptop that is unusable out of suspend mode, I want to be able to use my laptop while it's near idling. Yes, I use WIFI, and I also use my laptop to see things I want to see. So at this point, just for this reason, I'm glad my laptop has an Intel chip in it, and I'm glad I get those 2.5 hours of battery life (I'd be interested in after-market quality batteries fyi) I can't see how hard it would be to prove your measurements inaccurate.

Re:Apple doesn't trust other batteries

[fuzzyfuzzyfungus]

You don't seriously expect that the internal battery is any more "apple manufactured" than the removable battery was, do you?

Apple, like pretty much all the domestic PC brands, has little to no manufacturing capacity in-house. Possibly some prototyping, and likely some customization/assembly; but all the serious manufacturing is handled by a bunch of OEMs and their suppliers. The cells will be sourced from some third party in any case.

Re:Apple doesn't trust other batteries

[derGoldstein]

How appropriate, then, that the one thing they *do* oversee in-house is the manufacturing processes for the *cases*. They've invested quite a bit in manufacturing process development and patenting, resulting in things like the "Unibody" laptops and those highly-resilient aluminum coating materials.

So many of their customers, after all, "judge a notebook by its cover"...