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
POST A COMMENT

103 Comments

View All Comments

  • SomeGuyonaBike - Tuesday, August 27, 2013 - link

    I understand and agree with general objections to carrier-installed bloatware (and because of this I won't decide whether or not to buy a carrier-branded X until details about the developer editions are public)... I'm just curious as to why reviewers are so negative about this particular piece of carrier bloat. Reply
  • Impulses - Tuesday, August 27, 2013 - link

    I think I disabled it on my sister's One X, wasn't really an issue... Reply
  • SomeGuyonaBike - Tuesday, August 27, 2013 - link

    I spent a few minutes playing with a demo unit at an AT&T store over the weekend. When I launched the "People" app it wanted to sync to an AT&T address book, but there was an option to decline. I wonder if opting out of using the AT&T address book is a permanent thing, or if you have to repeat the opt-out every so often. Reply
  • Tralio - Wednesday, September 11, 2013 - link

    AT&T address book is a bit of an annoyance for everyday use, even on the X it tends to open incredibly slow. On the other hand when switching to my X it imported all my contacts onto my device without needing to import from sim. This can be an issue when switching from some of motorola or other developers' older models with larger sims, especially with the X not having an sd card slot and not every user knowing they can import/export from their comp. On a side note though for at&t users (not sure about the rest of the carriers) all at&t stores have a sim cutter that they can cut your sim down to the smaller size if you'd prefer to import from your current sim card or just don't want to deal with activating the new one. Reply
  • jasperjones - Monday, August 26, 2013 - link

    Brian,

    I agree that smartphone line out/headphone out sound quality is still a bit of a challenge. Looking forward to your new audio test suite. It would be great if you guys could report RMAA results.
    Reply
  • Brian Klug - Monday, August 26, 2013 - link

    I like RMAA, but it's easy to get a lot of things wrong and isn't really mobile workflow friendly. We're going to try something different that's a lot more robust :)

    -Brian
    Reply
  • synaesthetic - Friday, September 06, 2013 - link

    The thing I would like most, that I can't seem to find anywhere for any smartphone, and something that affects audio quality with headphones to a greater degree than any other attribute...

    Output impedance.

    Please, for the love of all that is holy, why can't at least one device reviewer measure the output impedance of these phones?!
    Reply
  • cheinonen - Monday, August 26, 2013 - link

    I should find out this week if I'll have access to a new suite of tests or not. If I can do it, RMAA will look like child's play in comparison. Believe me, we're looking forward to it. Reply
  • Impulses - Tuesday, August 27, 2013 - link

    Are you gonna go back and test at least this year's flagships? It'd be nice to have a baseline, particularly since this is something manufacturers have supposedly emphasized (HTC with the One, LG with the upcoming G2). Reply
  • cheinonen - Tuesday, August 27, 2013 - link

    It looks like I'll have access to some new testing methods, but it will be a month or so until I can do them all probably (sorry, I have a large backlog of other things to get done right now). I'll plan to do a huge initial round-up of phones and tablets to get a baseline and create an article about the new tests. I also want to point out that audio tests might not run with the initial phone tests since Brian or anyone else will have to ship the phones to me in Oregon to test and it'll take them out of the hands for a few days.

    We haven't tested this yet, but we're hoping it really helps us set a standard for audio testing of phones and tablets.
    Reply

Log in

Don't have an account? Sign up now