why so big battery life differences with same chip (snap800) - different model

[golemus]

Can somebody explain why there still is so big differences in battery life between many different handsets which each of has the exactly same SOC and same OS...? Look at the reviews at the end:


There is 4 phones, 3 of them have almost the same size display and same SOC but there is dramatic difference in battery life. E.g. web browsing life:

LG G2 11:22h
Galaxy Note 3 9:04h
Sony Xperia Z1 5:59h
LG Nexus 5 4:46h


Especially puzzling is that the best and worst handset is from the same manufacturer (LG)!, and the best has 2.4x more battery life.


I have understood that it has to do with software optimizations and perhaps drivers. Do G2 and Nexus really have that different optimizations and drivers even that they are from the same manufacturer...?

How about if you root your phone or install a custom ROM? Would the epic battery life of G2 drop to the same level with Nexus5...? Isn't it likely that both would use same optimizations/tweaks/drivers in a custom ROM...?


If you are going to install CM or other customROM do the battery life tests (that are done with stock ROMs) give you really any added value? In otherwords, the optimizations that give epic battery life to LG or Samsung phones, are they also present in the customROM side...?

I mean Nexus5 seems to have a very poor battery life, and with non-removable battery it really does not encourage me to buy one.





The Sony Xperia Z1 battery tests are done, here's the score - GSMArena Blog
LG Nexus 5 battery life test - GSMArena Blog
Samsung Galaxy Note 3 battery life test - GSMArena Blog
LG G2 battery tests are done, here are the results - GSMArena Blog

 

[golemus]

and by the way if somebody know the battery life of Galaxy S4 i9506 (snapdragon 800 model) that would be interesting too

 

[John Bean]

Do the examples you quote use the same capacity battery?

Aside: "SOC"???

I do hate it when I see some erm... TLA... that means absolutely nothing to me

 

[Thom]

Thread moved from Android Lounge to sub-forum where device comparisons are discussed.

... Thom

 

[golemus]

Do the examples you quote use the same capacity battery?

Aside: "SOC"???

I do hate it when I see some erm... TLA... that means absolutely nothing to me

Not exactly, e.g. G2 has 3000mah and Nexus5 has 2300mah, so 1.3x more on G2. Lets say that you divide battery life of G2 by 1.3, then you get 8h 45min, which is still much larger figure than the 4h something of Nexus5.

 

[Slug]

Can somebody explain why there still is so big differences in battery life between many different handsets which each of has the exactly same SOC and same OS...?

It's because each device has a different power draw. The SOC (system-on-(a)chip) may be the same, the display sizes similar, but different display technologies, wireless/mobile network bands, not to mention various software additions, all add up to significant differences in power draw.

For example, a battery rated at 2300 mAh can power a device drawing 100 milliamps for 23 hours, or a device drawing 230 milliamps for 10 hours. (In other words, a device using more power will drain the same battery faster.) In that same example, a larger battery, rated 3000 mAh, could power the same device drawing 100 milliamps for 30 hours.

Based on the devices you list, I'd say that the G2 simply draws much less power from its battery than the others.

 

[Rxpert83]

Aside from obvious differences in battery size, there are many other considerations as slug mentioned above.

Your real world usage is always going to be different from the manufacturers estimates. I know I've nearly doubled that time listed for the n5

 

[Hadron]

May I just add that GSMArena's battery tests are pretty poor. For example, their standard methodology is to set the screen to 50% brightness, irrespective of what the light output of the screen is. So if different handsets produce different brightness (light output per unit area) when set to 50% (and factor of 2 differences are not unknown) then the battery tests are not remotely comparable between different handsets.

That's in addition to the differences that Slug mentions. I just raise it to point out that poor control in tests means that you are not comparing like with like, even ignoring the other differences between the handsets (hardware and software).

 

[binaryhermit]

Plus, different screen technologies use different amounts of power, AMOLED screens using more than LCD screens. And an AMOLED screen is going to use more power for lighter images than for darker images, whereas an LCD uses more power for darker images than for lighter images. There could also be differences in the CPU governor used. There can also be differences in how low the battery gets before the device shuts off. I'm guessing there's also differences between individual units of the same device.

TL;DR: There's a lot of other variables.