Battery Life

The Zenfone 8 features a contemporary 4000mAh battery, which considering the size and 169g weight of the phone is actually quite respectable and competes well with other alternatives in the market.

The features that might impact the battery life of the phone are the Snapdragon 888 SoC, less efficient than its predecessor, as well as the 120Hz display which lacks any more advanced power management. The latter aspect of the phone can be quite negative – while the 60Hz mode of the phone has an underperforming base power consumption of 615mW, the 120Hz mode raises this to a rather eye-watering 783mW on a full black screen at minimum brightness.

Anecdotally speaking, I’ve seen vast power regressions on almost all Snapdragon 888 flagship devices this year, all except for Samsung’s S21 Ultra. The Mi 11, Mi 11 Ultra, OnePlus 9 Pro, ROG Phone 5 all exhibit quite bad base power behaviour, and the only difference to the S21 series is that Samsung employs Maxim PMICs and Broadcom WiFi solutions rather than Qualcomm’s own chips. I don’t know if there’s a correlation there or not, but the Zenfone 8 shows similar lacklustre efficiency.

Web Browsing Battery Life 2016 (WiFi)

In the web-browsing test in Auto mode which switches to 90Hz inside of the browser, the Zenfone 8 tracks rather closely to the Zenfone 7. The predecessor has a 25% larger battery, but also has a much larger display. The contemporary comparison to make is the smaller Galaxy S21 which lands ahead of the ZF8 even though it runs at 120Hz mode, and far ahead at 60Hz.

I’ll be updating the article with fixed 120Hz and 60Hz results for the ZF8 in the coming days.

PCMark Work 2.0 - Battery Life 

As noted in the performance section, “Auto” mode actually fixes itself to 60Hz in various applications, such as PCMark. The ZF8 here in its best-case scenario lands actually quite well in the relative positioning, meaning battery life in this mode is relatively competitive.

Again, I’ll be completing the result set with other refresh rate modes in the comings days.

Generally speaking, the Zenfone 8 finds itself in a tough situation when it comes to battery life. The 90Hz and 120Hz modes are really inefficient due to extremely lacklustre base power consumption behaviours. If you were to use your phone at very high brightness levels, the luminance power would vastly overcome that disadvantage and one probably wouldn’t notice the deficit as much, but at lower brightness levels, the phone would last much less than comparative devices.

The conundrum with this situation is that while 60Hz seems to be efficient for the Zenfone 8, it’s also not an as quite good experience when it comes to performance and responsiveness. So either you’ll have to deal with a responsive and inefficient device, or with an adequate battery life but sluggish feeling phone.

GPU Performance Camera - First Impressions
POST A COMMENT

65 Comments

View All Comments

  • shabby - Wednesday, May 12, 2021 - link

    If no sdcard is available then the storage options should be increased, 256gb isn't enough.
    The galaxy s10 had a 1tb option and it still had an sdcard.
    Reply
  • Boopop - Thursday, May 13, 2021 - link

    I've been using a Sony XZ1 Compact for the past three years, without much of an issue. 256gb would be plenty for me, this ASUS phone is appealing. Just because 256gb is not enough for you it doesn't mean it's the case for everyone. Reply
  • Boopop - Thursday, May 13, 2021 - link

    (which only has 32GB of storage, without an SD card). Reply
  • shabby - Thursday, May 13, 2021 - link

    Some people just don't use their phones to their full capabilities 🤷🏼‍♂️
    I have 55gb of apps, 30gb of photos and 90gb of videos.
    Reply
  • hemedans - Thursday, May 13, 2021 - link

    i have xz1 compact too, and it does have sd card, where did you get yours without sd card? Reply
  • nico_mach - Wednesday, May 19, 2021 - link

    If you never install an SD card, then it doesn't have an SD card.

    ;-)
    Reply
  • drajitshnew - Thursday, May 13, 2021 - link

    I already have have 100+GB. And I don't take 4k videos because of storage anxiety Reply
  • BedfordTim - Thursday, May 13, 2021 - link

    It is all about the trade offs at the price, but it is certainly a major limitation in terms of what you can do with the phone. Reply
  • notb - Tuesday, May 25, 2021 - link

    Good thesis, bad logic.

    A successful product is not a product that SOMEONE will like. It's a product that many people will like.

    Asus is pretty good at making niche phones that almost no one buys. So the question is: when (if ever) they start to focus on smartphone business as something they want to have an important role in (as in laptops). For now they're merely notifying their existence.
    Reply
  • Linustechtips12#6900xt - Thursday, May 13, 2021 - link

    as a galaxy s10e user this looks like a great upgrade, other than the no wireless charging bt otherwise very very compelling for me honestly Reply

Log in

Don't have an account? Sign up now