Mobile phone batteries are getting bigger and bigger, while the screens are becoming increasingly power-hungry.

Android flagship phones in 2026 have all crossed the 8000mAh battery threshold. The Honor WIN2 comes with 10100mAh, OnePlus 16 9000mAh, Xiaomi 18 Pro Max 8500mAh, and iQOO 16 8400mAh. Flagship models from three years ago generally hovered around 5000mAh. Yet users' actual experience has not changed, they still need to charge their phones twice a day.

The fuel tank is larger, and the accelerator is also pressed down harder.

First, look at the fuel tank

8000mAh is no longer a selling point, but a passing grade.

OPPO Find X10 Pro Max has an 8000mAh battery, and REDMI K90 Pro Max 7560mAh. Moving down the product line, the standard version of REDMI K100 and Honor WIN RT both reach 10000mAh, with the same starting price of 3499 yuan. According to e-commerce pages, the OnePlus Turbo 6X Pro starts at 1999 yuan and is also equipped with an 8000mAh battery. Mid-range phones no longer feature "smaller-sized batteries".

The underlying technology is the silicon-carbon anode. The energy density of this material has reached 850 to 1000Wh/L, while the upper limit of traditional graphite is around 800Wh/L. In the same battery compartment, more than 20% extra power can be stored. Flagship models are even more aggressive: the special-shaped dual L Jinshajiang battery of Xiaomi 18 Pro Max reaches 946Wh/L, and the 5th generation Qinghai Lake battery of Honor Magic9 Pro Max hits 1000Wh/L.

The body thickness has barely changed. Honor WIN2 with 10100mAh battery is 8.5mm thick; Xiaomi 18 Pro Max with 8500mAh battery is 8.39mm thick.

For batteries, it was a technical problem three years ago, but now it is a procurement issue.

Then look at the accelerator

On the same phone, there are two other components that are consuming power desperately.

The first one is the screen. The specifications of flagship phones have been pushed to 2K resolution, 165 to 185Hz refresh rate, and 2800 nits global brightness. OnePlus 16 is 1.5K 165Hz, iQOO 16 is 2K 165Hz with 2800 nits global brightness, and Honor WIN2 directly adopts 2K 185Hz.

Every step up in brightness brings a corresponding step up in power consumption. When iQOO 16 was released, the official gave a figure: the power consumption of this 2K screen is 31% lower than that of a 1.5K screen of the same size. Reading it the other way around, every upgrade in resolution comes at the cost of a real double-digit percentage increase in power draw. And the screen is precisely the component that is easiest to differentiate in the past two years, so no one is willing to stop first.

The second one is on-device AI, which is more hidden.

Operations on the screen are burst loads: swipe once, calculate once, then go to sleep. Local inference is different. The model keeps running on the NPU, the memory bandwidth keeps feeding data, and the device will not enter the low-power state halfway. One study gives an upper limit that continuous on-device AI operation will make the overall power consumption of the device about 30% higher than that in regular use.

What is more troublesome is that the hottest product direction in the second half of 2026 happens to be "agent phones" — Step Star, Nubia and OPPO are all promoting such products. These products require resident background operation and wake-up at any time, which means keeping the NPU always awake.

Screen power consumption is visible, while AI power consumption is hidden.

An overlooked comparison

Battery cell engineers once said a very straightforward sentence: the increase in power consumption is the direct reason why today's 6000mAh battery is less durable than the 5000mAh battery in the past. Converted, the actual battery life corresponding to 7000mAh may only be equivalent to the experience of the 5000mAh battery in the past. The capacity is rising, but the equivalent battery life is not. That is why the battery parameters are getting better year by year, but range anxiety has never disappeared for a single day.

There is another factor that helps cover this up. The fast charging of these models generally reaches the 80W to 100W level: OnePlus 16, iQOO 16 and Honor WIN2 all support 100W, and OPPO Find X10 Pro Max supports 80W. After energy replenishment becomes faster, fast power drain is not so glaring — you will not necessarily get anxious about fast power consumption, because you can leave after plugging it in for more than ten minutes.

Fast charging makes high power consumption tolerable, but it does not reduce power consumption.

Why this year

Three conditions have been met at the same time.

The first is technology. The mass production of silicon-carbon anodes has matured, and the energy density has jumped from the ceiling of the graphite era to above 850Wh/L. The capacity issue has changed from an engineering challenge to a procurement issue.

The second is demand. On-device AI has pushed up power consumption, making battery life change from a bonus item to a passing grade. If a flagship phone is only marked with 6000mAh, it would be embarrassing to mention it at the launch event.

The third is competition. After fast charging reaches around 100W, there are no new selling points. The camera sector has been rolled up to 200 million pixels, and the screen sector has been rolled up to 2K 185Hz. The only remaining area where a gap can be created with a single number is the battery.

The battery has become the last remaining position in this year's launch events that can win by a single parameter number.

Between the parameter sheet and actual user experience

The parameter sheet shows 9000mAh, but users still need to charge twice a day. Both statements are true, because they measure different things. The parameter sheet records how much power is installed, not what consumes that power.

A 9000mAh battery paired with a 2K 165Hz screen and a background-resident on-device model may have shorter available runtime than a 5000mAh phone with 1080p screen from three years ago. The number has increased by 70%, but the actual experience stays where it was.

The parameter sheet only records how much power is stored, not how much power is consumed. Because there is no number for energy efficiency. Increasing the fuel tank is the easiest answer. It requires no explanation, only a number.