Some smartphone releases this year have shown us that bigger batteries aren't always going to keep coming. Samsung opted for smaller power cells in its Galaxy S6 than the previous generation – in favour of faster charging. Apple's iPhone 6S Plus has 2,750mAh battery, making it smaller than last year's model.
But some people want to avoid charging as long as possible. Some of us want bigger batteries.
We've rounded up the big boys in the phone battery world to deliver the phones with truly huge batteries of 3,000mAh or more.
Of course bigger batteries don't always mean longer use, with screen size and processor performance to be taken into account. But generally a larger battery will help. Just look at the larger Sony Xperia Z5 Premium or Samsung Galaxy S6 edge Plus that can deliver over a day's heavy use easily.
So what smartphones can you buy now with a 3,000mAh battery or larger?
Samsung Galaxy S6 edge Plus: 3,000mAh
The Samsung Galaxy S6 edge Plus offers more screen than any Samsung before it thanks to that edge to edge curved display. But with a 5.7-inch Super AMOLED display power draining is always going to be an issue. That's why Samsung has opted for a hefty 3,000mAh battery in the handset.
This battery isn't the largest but coupled with Samsung's octa-core Exynos processor power consumption is kept to a minimum. This battery is also able to fast charge and even charges quickly wirelessly. In our review a 16-hour day of use still had 15 per cent in the battery at bed time.
OnePlus 2: 3,300mAh
OnePlus has taken the world by offering hyper specs at an affordable price. It's also dishing out plenty of battery life in its OnePlus 2 which crams in a 3,300mAh unit.
A 5.5-inch 1080p display chews battery despite the Snapdragon 810 processor efficiency. Yet we still found this handheld powerhouse took just two hours to charge to full. Then it kept going after 24-hours of use with still a good 10 per cent battery remaining.
Sony Xperia Z5 Premium: 3,430mAh
Sony's latest entrant to the Xperia family carriers a screen like no other smartphone, at a whopping 4K. That's a 5.5-inch LCD IPS running a 3840 x 2160 resolution - a lot of pixels to power. Hence Sony putting in a hefty 3,430mAh battery in this model.
The handset offers Quick Charge 2.0 and Sony's smart battery saving extras. Sony has added memory to the display, meaning that the CPU can be cut as soon as the display is showing what's needed. The result should be two days of use in Stamina Mode.
Motorola Moto X Play: 3,630mAh
The Motorola Moto X Play starts at £295 yet offers a 5.5-inch 1080p screen, 21-megapixel camera and - get this - a massive 3,630mAh battery.
The battery combined with octa-core Snapdragon 615 processor can offer, Motorola says, a full 48 hours of use on a charge. It should even be able to fast charge for 8 hours of use in just 15 minutes.
LG G4: 3,000mAh
LG really pushed the camera tech in its G4 to the limit. But it wasn't solely focused on that as it also squeezed in a hefty 3,000mAh battery to offer the best battery life. But despite a Snapdragon 808 processor the phone still only manages a day on a charge, if that. Not a great battery life leap forward from the G3 then.
Google Nexus 6: 3,220mAh
Google's largest Nexus smartphone was always going to come with a large battery. Complaints about the Nexus 5 battery life were rife so what better way to keep that energy juicing 6-inch screen on the Nexus 6 alive than by putting in a 3,220mAh battery?
This isn't the largest battery out there but it's plenty big and can be charged faster than most thanks to its Qualcomm Quick Charge 2.0 compatibility. And, also unlike most, it comes with a fast charger in the box meaning 6-hours use from a 15-minute charge. On a full charge, Google says, it will go all day even with lots of use.
HTC One Max: 3,300mAh
The HTC One Max, as its name suggests, large with a 5.9-inch display to keep up and running. That's why it's packing a 3,300mAh battery.
According to HTC it can manage 585 hours of 3G standby. Although with the now-dated Snapdragon 600 processor that battery could be used more efficiently by more modern handsets.
Samsung Galaxy Note 5: 3,000mAh
Samsung downsized on battery in the Note 5, going to a 3,000mAh unit. It also refraining from releasing the handset in the UK initially.
Nonetheless battery life, with the new Exynos 7 octa-core processor is reportedly better and also offers fast and wireless charging options. Not bad considering it's powering a 5.7-inch QHD display.
Huawei Ascend Mate 7: 4,100mAh
The battery on the Huawei Ascend Mate really is something impressive standing at a whopping 4,100mAh – bigger than most others out there.
The screen is 6-inches meaning plenty of drain but the processor is an octa-core Kirin 925 at 1.8GHz, which is efficient. Add in various battery saving app tweaks and the result is a battery that gives a good two days of use.
Microsoft Lumia 640 XL: 3,000mAh
One of the newest smartphones from Microsoft, unveiled at MWC, is the Lumia 640 XL.
This 5.7-inch Windows Phone packs in a 3,000mAh battery and is coupled with a 1.2GHz quad-core processor. Windows Phone handsets have, historically, had decent battery life so one with a battery this size should last a good day at least. Microsoft claims it'll manage 39 days of standby time.
OnePlus One: 3,100mAh
The OnePlus One crams in impressive specs including a 5.5-inch HD display and Snapdragon 801 processor, from just £230. The battery doesn't come up short either with a 3,100mAh offering.
That battery should stretch to a good day and a half of heavy use.
Samsung Galaxy Note 4: 3,220mAh
Samsung's Note series is now synonymous with large batteries to keep those big screens going. But thanks to Super AMOLED screen efficiency, coupled with the Qualcomm Snapdragon 805 processor, drain is kept to a minimum.
So that 3,220mAh battery should provide plenty of use on a charge for a full day even with heavy use. The Note 4 charges 30 per cent fast than the last model and, Samsung says, should offer 50 per cent battery after a 30-minute charge.
LG G3: 3,000mAh
The LG G3 has a large display at 5.5-inches, despite its form remaining relatively compact thanks to the lack of bezel. But it also manages to cram in a 3,000mAh battery to keep that Quad HD display up and running.
The G3 comes with a 1.8A charger meaning it will charge faster than most, even with that large battery. And it should deliver a solid day even with quite a bit of use.
Sony Xperia Z3: 3,100mAh
The Xperia Z3's 3,100mAh battery is actually smaller than that found in the Z2. But thanks to a greater processor and screen efficiency it actually still boasts an excellent battery life.
With a 5.2-inch display and an all day run-time the Xperia Z3 battery leaves few complaints.
Asus Zenfone Max
Asus took the wraps off its aptly named ZenFone Max which boasts a hefty 5,000mAh battery.
That juice box is powering a 5.5inch display and a Snapdragon 410 processor so expect to get plenty of life out of this all day powerhouse.