Battery Life

Battery life is a huge concern in the smartphone space these days, especially as phones get bigger and more powerful. The Moto X includes a unique 2200 mAh, 3.8 V (8.36 Whr) stacked battery made by LG chem, which maximizes battery volume given the Moto X’s rounded form factor. Motorola was very vocal about the battery life of the Moto X, and made the claim of up to 24 hour of mixed use with the device in addition to up to 13 hours of call time. Given the smaller (albeit AMOLED) display and dual core SoC, the Moto X was an easy target for the narrative that higher end specs and quad core SoCs are killing smartphone battery life, which many immediately latched onto and parroted claims of amazing battery life.

The Moto X's stacked battery

Of course, the real question is how the Moto X stacks up to the competition in our objective tests. I have to admit that my initial subjective impressions of the Moto X battery life were not all that great. My first time daily driving the Moto X was after getting it in NYC and flying home – I left the hotel with it fully charged, spent 4 hours in a plane with it in airplane mode, and Moto X still died in the baggage claim before I could make it home. The second time I daily drove the Moto X, I also managed to kill it doing nothing out of the ordinary before I got back home. I honestly can’t remember the last time I drained a phone completely actually using it. Since those couple of times I haven’t had problems making it through a full day when I’ve daily driven the Moto X, but that’s with my usual opportunistic charging from every available wall socket and USB port, and my mixed use definitely isn’t 24 hours, rather closer to 8.

Our objective battery life tests are unchanged so I’m not going to go through all of it in excruciating detail again – you can read any previous review and get the details. At a high level we calibrate the display to exactly 200 nits, then run through a bunch of webpages with content every dozen or so seconds until the device dies, on both cellular, and WiFi. The call test is self explanatory – there’s voice at both the originating terminal and terminating terminal, and we time how long the call goes for until the device dies.

AT Smartphone Bench 2013: Web Browsing Battery Life (4G LTE)

AT Smartphone Bench 2013: Web Browsing Battery Life (WiFi)

Cellular Talk Time

Battery life on the Moto X doesn't turn out to be all that much different from the other flagships based on APQ8064 on LTE. In fact, it's about par. That's not too surprising for me considering compared to the HTC One and SGS4 it's the same CPU (Krait 300) and process (28nm LP). For better battery life we'll need better efficiency, which will come either through newer process (28nm HK-MG variants at TSMC) or even more efficient CPU architecture.

In reality, having fewer cores here means in something multithreaded like our battery test (Chrome is very multithreaded) it needs to send the Moto X's two cores to a higher frequency and voltage state than the four on the other devices. I'm not surprised at all to see invalidation of the "fewer cores translates to better battery life" narrative others have crafted. The only validation is that having two fewer cores does translate to less dynamic range in power use. It all becomes a matter of how you're using the device at that point, however. On WiFi the Moto X does do pretty well, and Motorola has always had very good talk time. 

One thing I will note is that the Moto X does have a power saver mode, but it appears to just disable background sync and put the data connection to sleep aggressively. It doesn't change the governor so that the max CPU frequency is lower (say the 1.1 GHz state) like a lot of other OEMs power savers do, which seems like a missed opportunity. 

The Moto X comes with a dual-USB port 850 mA charger, like the previous revision of Motorola devices. In practice I've seen the Moto X reliably pull closer to 1 A from the Moto X bundled charger.

What's interesting however is that the Moto X can charge up to the maximum BC1.2 rate of 1.5A. If you use that kind of charger, it charges impressively fast, around 2.3 hours. 

Device Charge Time - 0 to 100 Percent

Display & Sound CPU Performance


View All Comments

  • Heartdisease - Wednesday, August 28, 2013 - link

    Well that's strange. My Galaxy Nexus has had burn in for quite awhile and it is getting more pronounced. Turn any amoled 180* from your normal orientation and look where the on screen buttons were. If you don't see it on the rest of the screen your blind. Reply
  • smitty123 - Monday, August 26, 2013 - link

    " You have to also be close by, Moto X isn’t going to turn on when you’re across a big room, for example. In addition I’ve noticed that for some reason there are some odd false positives."

    i don't like to feel like my spied on.

    So to me it just sounds like we have a new thing to test: the distance at which the phone can hear us.

    Not hear the magic phrase, just how far from us it can still hear us with its 3 mics. forget the "it can't understand us" i'm not testing if it can recognize words, i'm just not comfortable knowing if it can record conversations that a human, nsa for example, can understand. with obama going for the warantless conversation recording, let's just say, this isn't a phone i'd want near me.

    That old big brother spying thing is here, i think in the interest of privacy, we need to know these things before buying the phone.

    i for one will never get an xbox one just for that reason.

    good luck but i'm going back to good old rotary phones lol
  • flyingpants1 - Wednesday, September 18, 2013 - link

    All phones can do that, genius. Reply
  • AnnonymousCoward - Tuesday, August 27, 2013 - link

    Does the UI have lag between Android menu screens? Is the touch-screen at least as responsive as every Iphone to come out?

    I'm guessing there's still plenty of UI lag. In the future, UI's will be instant.
  • eallan - Tuesday, August 27, 2013 - link

    It's pretty responsive, I've had some hiccups and frame rate drops though. Reply
  • Honest Accounting - Monday, September 16, 2013 - link

    In the general UI or specific applications? Reply
  • Krysto - Tuesday, August 27, 2013 - link

    Maybe it got offset by the last-gen AMOLED tech. Here's the thing. If you're going to argue for efficiency, then don't just use an "old panel". Obviously that won't help. You need to use the latest technologies, the most efficient ones, and THEN lower the resolution and the clock speed of the CPU and GPU.

    So let's say the latest AMOLED is 2x more efficient than the n-1 before it, at the same resolution. But at 1080p (2x more pixels) it uses just as much power compared to the 720p one. Then I want the latest AMOLED with 720p, to benefit from that improvement in efficiency. If I use the old one with 720p, or the new one with 1080p, then I won't see any improvement in battery life.

    Same for the CPU and GPU. Let's say Motorola wanted to hit the performance target of S4 Pro, in both CPU and GPU. Great. But to gain extra efficiency, it would've been ideal to use the S800's CPU at 1.5/1.7 Ghz (instead of 2.3 Ghz), and Adreno 330 at half the clock speed (to match Adreno 320's performance).

    That's how you get the extra efficiency. We don't really see new phones that are much better in power consumption than last year's models, because the OEM's keep pushing for performance or resolution or whatever, which completely cancels out whatever efficiency gains they might've had.

    But this is our fault, too. Because we keep caring about benchmarks and who's e-penis is bigger, to the point where the OEM's have the incentive to cheat on these benchmarks, to get good PR from it.

    If we really want to see better battery life, then act like you don't care about performance anymore (because it has gotten good enough anyway), and ask for 2-day battery life (then heavy users might finally get a full day).
  • Impulses - Tuesday, August 27, 2013 - link

    The whole efficiency line on Motorla's part is probably half marketing spin anyway, I'm sure cost and logistics played as large a role into the component selection as efficiency, even features (the active display stuff would've been impossible w/more common LCD displays, etc). At the end of the day, the only phones that have made monumental battery life strides have been their MAXX editions, by just packing a much larger battery... It seems current gen phones often catch up to last gen MAXX phones in one or two tests tho.

    If they were really trying to go for battery life above all they'd not only sacrifice some performance but some device thickness, and introduce a phone w/a MAXX-like battery as the only SKU w/no smaller battery model below it. I'm surprised more OEMs aren't putting out slightly thicker phones at times w/3,000mAh batteries like Moto, like not even one OEM has...
  • michaelljones - Tuesday, August 27, 2013 - link

    Brian, Anand,

    I know I'm commenting awfully low in this list to get seen, but I'd like to see a little more love for Windows phone in some of your comparison graphs. Throw in at least a token Lumia please (or more if you like!)?

    I'm a happy Windows Phone user (like many I think), but I have no way to quantitatively compare my Lumia 928 to any of the other handsets. With cameras that kick ass, I can't see how they aren't a comparable discussion.
  • teiglin - Tuesday, August 27, 2013 - link

    Two Lumias feature prominently in the camera section, and more are in the full gallery of camera comparison shots. I mean, yeah, Brian clearly knows that Nokia kicks everyone else's cameras in the nuts, and it shows.

    Beyond that, where do you want to see the Lumias? I don't think Brian ever got a working Windows Phone battery life test because of screen timeout issues (not to mention the absence of precision brightness controls makes it hard to compare to controlled 200 nit settings), so that leaves javascript benchmarks and display quality. I guess those would be nice to see in the appropriate charts.

Log in

Don't have an account? Sign up now