Z70V - 4300 mAh battery?

Guys,

The sticker on the batt that came with my Z70V says "4800 mAh". But when I run BatteryMon it lists

"Design capacity: 69000 mWh (4312 mAh)
Full charge capacity: 68430 mWh (4276 mAh)"

Huh? Where's the other 500 mAh? Is this similar to what others see? Are there multiple versions of this battery and perhaps I got a mislabled one?

I also bought the optical tray battery, which says "3600 mAh". BatteryMon shows this as 3629 mAh, so at least this checks out.

 

That seems a little low, but it's the only battery so you couldn't have gotten anything else.

 

Hi Justin,

Thanks for the info. The reason I ask about the multiple batts is this -

"I remember Justin saying that another reason for less weight is that ASUS often weigh it with a low capacity battery"

http://forum.notebookreview.com/showpost.php?p=1106488&postcount=29

So have you ever instrumented the battery and seen this to be the case? I noticed some folks had mentioned Asus has a history of flubbing specs, is this one of those?

 

Not with your notebook....... with the W3..... the W5.... the V6...... all of those becasue this year Asus brought all of those units over with the bigger battery and the world "standard" battery isn't even an option.... but the battery in the Z70 has been the same battery they've used in December of 2003 in that M6 series..... so for that there is only one battery.

But Asus doesn't lie about specs...... if they give the specs of a unit ... like the z70v for instance..... they weigh them with the travelers drawer becasue that's the lowest weight the unit can have and be used normally......... they give maximum battery life you can get out of a unit with a certain spec........ those things change as you go up in hard drive and cpu and usage, obviously....

I'm going to run a test on my units tomorrow and see how they stack up (the 8 cell batteries that is) ..... which battery monitor were you using? I'd like to use the same one.

 

I'm using BatteryMon

http://downloads-zdnet.com.com/BatteryMon/3000-2094_2-10356871.html

 

This is odd... after removing and reinserting, my OD drive bay battery now shows 3326 mAh in BatteryMon. Hmm, maybe this software is glitchy. Is there one you prefer? I downloaded this as a recommendation from notebookforums.com.

 

Just curious - why is 5.6 listed w/TD, when it sounds more like over 6 from some reports?

I'm not accusing anyone of lying. I've had my share of troubles due to marketing/salesfolk getting features incorrect on stuff I've worked on. People make mistakes.

 

dunno if it CHC is any good for battery monitoring as i dont believe that was it primary purpose but anyway mine is also reading at 67380 mWh max and this is after a 2% wear down with its origonal rating being the 69000 mWh. It gets about 4hrs with undervolting...

 

Just checked with CHC, same specs as well.

Haven't literally timed a battery run but BatteryMon tells me (w/both batteries) 5:15 after sampling for a few hours is about all I have. That's with the 6x @ .7 v, screen brightness 3rd tick from the bottom. Would be a challenge to get much more. If I could push the main to 4 hours that would be 2.5 with the OD, 6.5 hrs. total would be a dream... allowing for lunch/breaks that would just about carry me through a workday.

 

Can anyone else confirm this as well so I know it's not an anomoly?

Justin,

Have you been able to test this? It would be nice if these are truly mismarked, as well as the weight of the unit, if Asus would correct the specs.

 

Something funny I noticed - with the main alone it claims I can do just under 4 hours, and about 3 with the OD bay battery by itself. But with both together, 5:15. What happened to the 1.5+ hours?

Also I noticed with the primary at like 90% charge it showed 3:35, but then I slipped a virtually dead OD battery in (5%) and it _lost_ time, down to 3:05.

Funny math there. Someone should buy this program a calculator, lol. Someday soon I'll literally time it.

 

Alright, now this is really weird.

Pertaining to the problem above, with both batteries the machine draws ~21-22 watts, whereas with each battery individually it's 16-17 watts. This has to be some bug in the bios... and I just upgrade to 2.0.6

 

All of the 8 cell's are coming in at about 4500mAh........ the problem is, they are fluctuating a LOT and I have a feeling this battery monitoring software is a bit buggy, but it's not that far off....... all of the batteries should essentially be the same between models. 90% of our notebooks have the same 8 cell set up. All of them are coming up between what's basically 7 1/3 cells to 7 2/3 cells...... probably about right.

 

Hey Beau10, I know you mentioned that you had OCD in another thread, that's why I gave up. But come on, getting to the readings? Batteries do fluctuate here and there, even in different temperatures, usage, and through time. If it works, then it works. They already assured you that it was brand new and sealed from the manufacturer. If I had OCD, I probably wouldn't question the battery, but the programs that you're using to do the tests with (which also uses up resources). Their not exact.

 

..... Well it's somewhat like the way that hard drives aren't exactly 80/100gb.... but maybe 76/96gb etc.......... My best guess is that the battery monitor isn't perfect to begin with....... and each one of the cells are slightly smaller than 600mAh.... I'm getting about 560/570mAh per cell. The battery is rated by multipling the cells used in the battery. Each cell is like a AA battery and those are rated from the actual battery maker.

 

Look guys, there are two bits of info the battery is reporting

1) The controller on the battery has a spec that it reports back - this is coming in at 4300 for the main, 3200 for the OD. This _should_ match the spec posted by ASUS. This has nothing to do with how the battery is actually performing. That's why these values in mWh are in nice round numbers. I'm curious about the 4500 you reported above Justin, someone else reported 4300 as well. Guess I'll go register at Notebookforums.com and see if I can get more data on this. Regardless if the spec is wrong Asus should fix it. Again, people make mistakes all the time, but when once pointed out it's simply unethetical to fix. As well the weight of the device.

2) The value reported in actual use, which is a measurment and should be fairly close to the spec when new. Of course over time wear will drag this value down. I will accept this value will be high or low as it should be.

1 && 2 aside, the interesting behavior with the OD and main in tandem is most surely a bug that should be adressed as it is a functional problem. I will suspend disbelief and instrument it with the ol stopwatch to see if this is indeed true.

The battery statistics were the same both in CHC and BatterMon, the chance for both programs to contain the same bug are slim.

The OCD comment was a bit of a joke, but surely there's some truth there - as would be with any sr. level engineer (which I am) worth a grain of salt.

 

Right, but that's a marketing thing taking advantage of the typical consumer's ignorance that a gig is a billion bytes. The definition is hazy. And you could also talk about how CRTs used to be measured by the tube size rather than the actual viewable area... of course in that case the industry was taken to court and had to reevaluate.

The definition of a mAh is not in question. You can't market it in any other way. If a battery is more than 10% low that's pretty significant.

 

1. Nope, not wrong...... like was said about that stuff can never be accurate. 4300 is a bit lower, but 4500 is where they should all be. If a single cell is rated at 600mAh.. if they are using 8 cells then its' 4800mAh....... But those single cells might actually be 570mAh..... it's not Asus' problem, really. I think it's going to be an industry wide thing. But I also think the battery monitor isn't reporting 100% correctly either.

The optical drive battery showing up as larger than it should be is weird... because that shouldn't.

 

Where did I say that? I said the batteries running in tandem cause the draw to jump several watts, eating up something over 1.5 hrs. of runtime.

I'll let the battery spec thing go, I've said what I need to say here... will continue this over at notebookforums.com for more data points.

 

Up there..... you said the 2nd battery was showing up at more than 3600mAh. ... that's all.

 

Ahh, yes, that was unusual. FWIW, the battery _is_ marked to be 3600, so it would simply be correct, not high (if it were true, that is). My main has shown the same thing in all apps. Without a doubt there are problems with some software, driver, hardware, but it's hard to draw any conclusions without looking further into it.

 

But again, this doesn't mean something is wrong. Maybe it does, but it certainly doesn't mean Asus is trying to BS their customers. All batteries are usually sold as the number of sells and the coorisponding total milliamp hour rating for each cell times the number of cells.

I think the software isn't perfect, but neither is any battery. How's your life compared to other peoples?

 

Okay, I figured out the issue regarding the battery measurements.

I found a program called Battery Eater which reports measurements very close to the spec (4800 && 3600 mAh). It also reports a figure I didn't pay attention to and not reported in BatteryMon, the designed voltage. Which are 14.4V and 10.8V for the main and OD batteries, respectively. The actual measured values for my batteries are 16.7 and 12.5.

I find that when I divide the designed wattage of the batteries by the designed voltage you get the designed amperage. OTOH, when you divide the actual wattage by the actual voltage you get the low values reported. But power is what really matters in the end, sooo... this means the batteries are as they should be, and giving a current rating when voltage cannot be guaranteed is a very confusing thing to say the least. But all the same taking the designed voltage and multiplying it by the designed amperage will give you the designed wattage of the battery, which when new should be pretty close to what you're actually getting. This is a big caveat when looking at 3rd party batteries, make sure you do this calculation when comparing. Even with this laptop this is immediately apparent as the OD battery runs at a significantly lower voltage and has less power than one might assume from its rating relative to the main.

As to the issue with both batteries together drawing more juice, more info on that in a day or two... Battery Eater Pro can give pretty agrressive and accurate run down instrumentation. Will try 1) both together, 2) main only, and 3) OD only.

 

There you go. Good job! Now where did you get that current program?

 

Yes please repost the links on all forums. Someone will surely complain about this again in the future but this time we will be ready

 

Gotta be armed and ready.

 

Hey Guys,

Good news on the other problem. My computer was instrumented with Battery Eater Pro in 'idle' mode - basically doing nothing other than graphing the discharge info. With maybe a couple of hours of light web usage thrown in here or there, it was able to achieve 6 hours and 50 minutes. This is actually slightly better than what I predicted as a best case scenario.

Now I was indeed getting weirdness instrumenting it. Initially the standard MS issue Power Meter showed 5:15 with both batteries. When the first battery ran down to 5%, the PM reported just over 3 hours left. After it died and the OS switched to the main, the time jumped up near 5 hours. My theory is either the BIOS or the OS does not know how to properly handle batteries with differing specs, and when calculating power draw it is likely averaging the voltages of the batteries when both are used in tandem. So if you take a battery which operates at a low voltage and you use a higher one in your calculation, you will show less runtime.

With my old Inspiron this wasn't a problem. Both batteries were the same, you slapped in the other the time would double and it would treat them as one big battery - ie. both would decrease at the same rate. With this machine the OD battery is drained completely first, then the main.

Sometime soon I'll write up a guide on maximizing battery life, might have a few tricks here I haven't seen elsewhere, and include this weirdness I experienced when instrumenting, links to my tools, etc.