The most power-efficient phones: best battery life per mAh

The most power-efficient phones: best battery life per mAh
When it comes to the battery life of their puppies, there isn't much to brag with for most flagship phone makers. On average, they land with a little over 3000mAh capacity, which has proved insufficient for power users of their high-res displays and souped-up chipsets. It seems that phone makers are starting to get aware of the issue, and are increasingly equipping their devices with larger batteries.

Perhaps the best example is Huawei, with several 4000mAh flagships announced by now, but also Samsung, whose Galaxy Note 9 is landing with such a capacity for the first time. Still, what's the point of chasing the mAh count if the phone's hardware and software combo can squeeze it dry in no time? That is why we wanted to check which phones did best on our demanding battery test with the least capacity - the ultimate optimization challenge if you will - normalizing their endurance for easier comparison.

Methodology: [battery life (min.) ÷ battery capacity (mAh)] × average battery capacity = normalized battery life

We took the results from our battery life tests (in minutes) of 21 noteworthy devices from this and last year in two categories - phones with QHD (1440p) resolution and above, and phones below that high-res mark. We then divided them by the capacity of their respective batteries (in milliampere-hours). For each device, the resulting value (min/mAh) is then multiplied by the average battery capacity of all phones in the group, so that we can have the equalized battery life, i.e. how long would each phone last if all had one and the same capacity. Here's what we found in the two categories.

NOTE: This ranking doesn't show which phone has the best battery life. What it does is it shows us which are the most power-efficient smartphones out there!

Phones with QHD (1440p) or above displays

When it comes to endurance on a charge from flagships with 1440p displays or higher, we noticed a consistently worse performance compared to those with similar specs but lower resolutions. Granted, the default screen resolution on phones like the Galaxy S9 is FullHD+, but there are still more than 4 million pixels that have to be lit up. That's opposed to two million or so on "real" FHD displays, so it doesn't help to nudge the battery life up even one iota. Twice the number of pixels to push is perhaps the single biggest reason for QHD phones to score on average a 20% shorter endurance on a charge compared to the lower resolutions.

With that being said, there are still some outliers to rank well in this category, too, mainly phones with OLED displays (dare we say PenTile pixel matrix?), as well as the LCD-laden U11 whose result on our tests, as well as anecdotal evidence from its owners, show that HTC did a good job pairing hardware and software. 

Samsung is also not that bad in battery life when you normalize for the battery capacity in its phones, with the caveat that these are the Exynos models. After all, the tests are only able to shoe the screen-on time duration in a standardized situation before the software has started to gum up the works with a few months of usage. 

Phones with less than QHD (1440p) resolution 

Considering that the difference in pixel density between the two groups is barely perceived with the naked eye, manufacturers that aren't blindly chasing the resolution count seem to be doing a smarter job, as we can enjoy their phones much longer on a single charge. Even though the QHD+ group above has slightly larger batteries on average, they fare about 20% worse than the "below QHD" group here. 

Apple's iPhones seem to be the best performers in that cross-section, as Apple designs its own chips and software, optimizing the heck out of its phones' power draw. This way it shoots a few birds with one stone - it can put smaller batteries in its handsets than the competition, achieving economies of scale, and that also leaves a place for extra components to sprawl inside so that its handsets land thinner.

Sony and Motorola have traditionally eked out good battery life from their packs, and the stats show it. Samsung is doing well, too, but here we have to note that it's the Exynos version of its phones that perform in the top results, while the Snapdragon ones that the US gets are consistently scoring a tad worse in battery life than their Exynos counterparts.

As you can see from the tables with the normalized battery lives of popular phones, longer battery life, while always good, doesn't mean that the phone has the most optimized hardware/software combo in terms of power draw. Apple, Motorola, Sony, and, to a certain extent, Samsung's Exynos models, seem to be doing a good job in that respect, while HTC and LG also have a few outliers.

One thing is for sure, though - if you like a phone with a high-res display, wait for its battery life tests. All other things being equal, its endurance on a charge will be much worse than phones with sub-1440p resolutions, all for a pretty negligible difference in perceived pixel density, at least with the naked eye. Are you still chanting the "QHD or bust" mantra?



5. rsiders

Posts: 2015; Member since: Nov 17, 2011

I mean I know iPhones last long in these tests but I always see people at work on their break close to a wall outlet charging their iPhones. So either iOS users don't ever charge their phones before work or these battery claims are off. In fact I've only had maybe one person ask if I had a charger who uses Android.

7. steved13

Posts: 6; Member since: Apr 03, 2013

The difference between an iphone 6 and an 8 is night and day when it comes to battery life...

44. chbanks512

Posts: 79; Member since: Mar 07, 2017

We'll you have to look at the actual capacity. The iPhone has an 1800mAh battery....I mean that's pretty pathetic; I don't care how efficient the battery/processor may be, that's tiny.

12. CreeDiddy

Posts: 2275; Member since: Nov 04, 2011

No one cares about battery life anymore. Most people carry a car or USB charger or battery case charger. As long as I get 8-10 hrs without a single charge. Also keep in mind, Software is becoming more optimize and also people have learned to control their brightness through settings, etc...

14. paceman unregistered

Just because you don't care about battery life does not mean all of us, Right? One of the most important features on a phone is the battery if you are a heavy user like me and many others. Iris scanner, fingerprint scanner and stereo speakers is not important at all for me. We are different thats all!

26. Fellwalker

Posts: 542; Member since: Apr 04, 2014

Everyone knows that is wrong. Many care deeply about battery life. I certainly do as I use mine for maps when walking, on the golf course for distances and course layout, as well as the usual range of activities on a phone. You can't manage brightness outdoors; most phones need 100%. No-one I've ever come across CARRIES a car or battery case charger. I know one person who has an external battery pack that they use. I used to before I got a 4000 mAh Huawei mate 9, but it was a pain in the neck to remember and to find somewhere to keep it - I often had to carry a rucksack. External batteries are an inefficient way of recharging a phone,and have an enormous weight penalty for what they provide. A few I know have a car charger in their car, but that is only good if you're in the car. I don't doubt that you are happy with your phone, or that SOME whose life /job revolves round a desk or a car can manage with poor battery life.

40. wesley.

Posts: 217; Member since: Aug 06, 2013

You are wrong.

19. wando77

Posts: 1168; Member since: Aug 23, 2012

Back in the real world...... My iPhone owning friends always run out of charge about 5pm. Not so for anyone on a modern Android phone (galaxy note 8 here and the battery life is great in use or standby)

20. BullaBoss

Posts: 141; Member since: Jul 17, 2018

iPhones have good standby but terrible screen on time. Your opinion depends on what kind of use your day consists of. My gripe with these small iPhones is the pixel density. I see the grid while watching videos. It's getting to me at this point.

22. Valdomero

Posts: 704; Member since: Nov 13, 2012

Agreed, I have a 2017 iPhone 6 and its battery life's being pretty good. (98% battery capacity according to the Battery Health Beta in Settings) All those who have commented have seen people who have old iphones or phones with spent batteries I use the phone mainly for games, Youtube videos and Whatsapp. I rarely use it for Social Media. When I use the phone for gaming and Youtube the battery goes fast, that's normal. When I barely use the phone throughout the day it only goes about 1% - 2% an hour. As BullaBoss says, it all depends on how and for how long you use the phone. I haven't seen any pixels while watching Youtube, but the small screen is making my eyes hurt, I might get the iP8+ once my contract ends in November.

23. yalokiy

Posts: 1113; Member since: Aug 01, 2016

That LG V30 does have good battery life according to many reviews and G6 the poorest.

24. legiloca

Posts: 1676; Member since: Nov 11, 2014

So many bitter Android fanboys. Let's give credit where its due, iPhones have good battery life. period. Now go on spend the rest of your day enjoying your Androids too. Are we all happy now?

27. burkett375

Posts: 51; Member since: Dec 19, 2017

My essential phone is pretty good... How would that compare?

31. rouyal

Posts: 1583; Member since: Jan 05, 2018

Can confirm, by actual use, the iPhone 8 battery is great. With Android phones, I would always plug it in at bedtime to be sure I had enough for the next day. With the iPhone, I plug it in once every few days. Don't need to plug it in overnight. Pay no mind to the jealous fandroids whose phones drain from Google spying on them. An iPhone could make breakfast, and Android users would complain it didn't put enough salt on the eggs

34. TheOracle1

Posts: 2340; Member since: May 04, 2015

Sounds like no one wants to really communicate with you on that iPhone 8 and it remains on standby for your "every few days".

36. riteshrkm

Posts: 164; Member since: Apr 15, 2015

"Once in Every few days" Do you even use ur phone?

45. Marcwand3l

Posts: 456; Member since: May 08, 2017

You should have stopped after the first sentence.

32. deleon629 unregistered

The iPhone battery stats are true, guys. Maybe most of you are just, you know...charging it wrong *shrugs*

37. NinoH

Posts: 133; Member since: Feb 09, 2018

Just the fact that an iphone with 2715 mah battery can Outlast most android flagships is a statement in its own for me in terms of battery optimization. iOS wins hands down.

38. hemedans

Posts: 761; Member since: Jun 01, 2013

Where is galaxy A3 2017? That phone is more efficient than any iphone according to gsmarena tests

39. isprobi

Posts: 797; Member since: May 30, 2011

I am glad to see my Razer phone did quite well. I have no regrets after selling my Note 8 to get the Razer since it is very smooth and I do not need to charge it more than once a day. The speakers are really loud and pretty full range for a phone too.

41. Nkukza

Posts: 53; Member since: Feb 19, 2015

BS man that iPhone thing does not last even 6 hours without needing a charger and I'm talking about the biggest one of them all, optimization or not the thing has pathetic battery life for the price you pay for it and it's owners will never leave the house without a charge.. That Nokia 7 plus has way better battery life than rated here and My galaxy s7 had poor battery life too. I found xiami's line of Redmi note phones to have superior battery life to any mobile that exists today, it is almost impossible to kill the damn thing and it offers the best features with a trendy design with dual sim support.. This is precisely the Redmi note 3 and 4, Huawei's Hornor line, Mate and P series are also strong in this department then comes Samsung and Nokia. At the end of the list you will find Apple and right at the end of it is Sony and LG with equally pathetic battery life in all their devices.

42. Nkukza

Posts: 53; Member since: Feb 19, 2015

For me phones with the best battery are as follows: # Moto Z play first edition # Redmi note 4 or 3 #Huawei Mate 10 standard or Pro # Galaxy Note 8

43. Nkukza

Posts: 53; Member since: Feb 19, 2015

For me phones with the best battery are as follows: # Moto Z play first edition # Redmi note 4 or 3 #Huawei Mate 10 standard or Pro # Galaxy Note 8 # Nokia 7 plus

* Some comments have been hidden, because they don't meet the discussions rules.

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