When we think of big smartphone batteries we tend to think of something around 3600mAh, like the one in the Samsung Galaxy S7 Edge, while a unit the size of the 5,100mAh one in the Lenovo P2 is almost unheard of.
Or at least, it is in the west. But head over to Asia (or brave the import market) and you can find phones with batteries that dwarf either of these, and even some handsets with more than one battery.
Need some examples? You’ve come to the right place. From largest to smallest, here are ten of the biggest batteries ever to grace a smartphone.
Oukitel K10000
- 10,000mAh
- 13.8mm thick
- Around $150/£120/AU$200
The Oukitel K10000 is a real monster, with a juice pack that’s almost twice as high capacity as the one in the in the Lenovo P2, and over five times bigger than the one in the iPhone 7.
Oukitel claims its phone can last 10-15 days on a single charge, which sounds optimistic to us, even with a battery that big inside, but it should certainly see you through the best part of a week.
And all that juice can be shared, as the Oukitel K10000 can also be used to charge other devices.
Elsewhere, aside from a design that wouldn’t look out of place in Tony Stark’s lab, the K10000 is a fairly unremarkable handset, with a 5.5-inch 720p screen, a quad-core chipset and 2GB of RAM, but those mediocre specs probably just help it last longer.
Gionee M2017
- 7,000mAh
- 7.4mm thick
- Around $1000/£800/AU$1345
The Gionee M2017 doesn’t just have one battery... it has two. But each of them is 3500mAh, which is already larger than most smartphone batteries, and together they give you 7000mAh of juice to sip.
Why it has two big batteries rather than one enormous one isn't clear, since they're not removable and the phone seemingly treats them as a single unit, but combined they can keep the phone going through over 26 hours of continuous video playback according to Gionee.
But there’s a lot more going on here than just a big battery, as this is a luxury handset with a seriously high-end price.
For that money you get a 5.7-inch curved QHD screen, 6GB of RAM, a dual-lens camera and a leather back, though it’s somewhat let down by a middling Snapdragon 653 chipset.
Doogee HomTom HT6
- 6,250mAh
- 9.9mm thick
- Around $145/£115/AU$190
Want a phone that you only have to charge once a week? Then you may want the Doogee HomTom HT6, which has a huge battery apparently capable of just that.
Of course we're spurious about those claims, because there are far more factors that have an effect on battery life than size (and the claims here are rather ambitious).
But the power pack is massive, so if you’re happy to settle for plugging it in twice a week the the HT6 should manage that nicely.
It also supports fast charging, so you shouldn’t have to keep it plugged in for long.
The rest of the specs are mediocre again, as it has a 5.5-inch 720p screen, a quad-core chipset and 2GB of RAM, but then it’s also got a low-end price.
Ulefone Power
- 6,050mAh
- 9.5mm thick
- Around $150/£120/AU$200
The Ulefone Power’s battery is only slightly smaller than the HomTom's at 6050mAh, but its time-between-charge claims of four days are much more believable than the previous phone's.
The Power out-specs some of the phones on this list in other ways though, with a 5.5-inch 1080p screen, an octa-core processor, 3GB of RAM, a fingerprint scanner and a build that includes metal and optionally wood, yet it still comes in cheaper than the Moto G4.
Gionee Marathon M5
- 6,020mAh
- 8.6mm thick
- Around $250/£200/AU$335
The second Gionee phone on this list is far less premium than the first, but its battery is ‘only’ 980mAh smaller.
And just like the M2017, the Marathon M5 actually has two batteries, each of which individually comes in at 3,010mAh.
Like so many of these battery monsters it’s a little underwhelming in other ways, with a 5.5-inch 720 x 1280 screen, a 13MP camera, 3GB of RAM and a quad-core processor.
It does at least have a metal build, but the look is nowhere near as luxurious as the Gionee M2017. Then again, the price is nowhere near as high either.
Innos D6000
- 6,000mAh
- 12mm thick
- Around $250/£200/AU$335
Another phone that thinks two is better than one, the Innos D6000 has a 3520mAh battery and a 2480mAh battery, totaling 6000mAh.
But while some of these dual battery smartphones have sealed batteries, the larger of the two in the D6000 is removable, and not only that, it’s removable without turning the phone off, as it can continue to run from the other unit.
That means if you’re the type to carry around a fully charged spare you can swap it in without any downtime.
The design of the D6000 is 2014-bland, but the specs are solid, with a 5.2-inch 1080p display, a Snapdragon 615 chipset, 3GB of RAM and a 16MP camera.
Bluboo X550
- 5,300mAh
- 9.5mm thick
- Around $120/£120/AU$200
The Bluboo X550 is a lower-end handset, with a quad-core MediaTek chipset, 2GB of RAM and a 5.5-inch 720 x 1280 screen, which in many ways makes it even lower end than the budget Moto G4 (a phone with a sharper screen and twice as many cores in its chipset).
But the Bluboo X550 has something the Moto G4 doesn't, as it has a massive battery inside with fast charging.
Compared to some of the phones on this list that’s on the small side, but it’s still far, far bigger than almost any phone battery released in the west.
Lenovo P2
- 5,100mAh
- 8.3mm thick
- £199 (around $250/AU$330)
While most of the handsets on this list are Asian oddities, the Lenovo P2 is actually from a known name, and readily available to buy in the UK (though currently not in the US or Australia).
In fact when we reviewed the Lenovo P2, praising its attractive metal build, great 5.5-inch 1080p screen and surprisingly low price. But of course, the battery is the real highlight.
In terms of size in the hand, the P2 might be one of the smallest on this list but it’s positively massive compared to most phones, and we found that it will last well over two days between charges.
Allview P8 Energy Pro
- 5,020mAh
- 8.4mm thick
- Around $435/£345/AU$580
Most of the phones on this list come from Asian companies, but the P8 Energy Pro is an exception, as Allview is a Romanian company.
And the P8 Energy Pro stands out in other ways too, with a 6-inch 1080p AMOLED screen, (far larger than even most phablets) but then that may have been necessary in order to squeeze the huge battery inside.
Elsewhere the specs are solidly mid-range, with an octa-core MediaTek chipset, 3GB of RAM and a 13MP camera.
And it’s a phone you won’t forget is in your pocket, if you can fit it in at all, as it’s 160.9 x 81.2 x 8.4mm and a hefty 209.8g.
Samsung Galaxy A9 Pro
- 5,000mAh
- 7.9mm thick
- Around $400/£320/AU$535
The Samsung Galaxy A9 Pro is another massive 6.0-inch beast, albeit one with an ever-so-slightly smaller battery than others on this list.
It’s also one of the more impressively specified phones on this list, with a 1080p Super AMOLED screen, an octa-core Snapdragon 652 chipset, 4GB of RAM, a fingerprint scanner, 32GB of storage and a 16MP camera with optical image stabilization.
It’s also got a metal and glass build, just like the Samsung Galaxy S7, but despite this being a Samsung phone it isn’t readily available in most of the western world.
Why? We’re not sure...maybe we give the impression that we like plugging our phones in every day.