If you’ve ever spent half your day babying your battery percentage, Realme’s latest concept might just blow your mind. The company has just shown off a phone with a staggering 15,000mAh battery inside—easily the biggest cell ever crammed into a smartphone. To put that in perspective, that’s about the same juice as five iPhones stacked together, or enough to make carrying a power bank completely pointless.
realme 15000mAh, that’s equivalent to the nearly combined capacities of an iPhone 12, 13, 14, 15, and 16—all together in one device!
— realme Global (@realmeglobal) August 28, 2025
Never has there been any phone that can fit a mega 15,000 mAh battery in its body. We made it. pic.twitter.com/cahUNL5dof
But here’s what’s wild: despite packing such an insane amount of battery, this phone isn’t some brick you’d need two hands to hold. Realme’s gone with a semi-transparent “Newborn” design, which doesn’t just look cool and futuristic, but also somehow keeps the phone slim and surprisingly light. For something with four days’ worth of battery on tap, it’s shockingly pocketable, even much more so than the Poco F7.
Now, there are many new phones that come with a 7000mAh battery, like the Oppo K13 Turbo Pro. With Realme's latest concept phone, the headline is that 15,000mAh cell, but there’s a lot more going on under the hood. Realme’s using next-gen silicon-carbon chemistry, which massively boosts energy density compared to regular lithium-ion batteries. Basically, you get way more power in the same footprint. Add in a folded circuit board design and a special high-transparency “pole piece” for better ion flow, and you’ve got a battery that lasts forever, charges efficiently, and won’t fall apart after a few cycles.
A phone with a 15000mAh battery. What does that really mean?
— realme Global (@realmeglobal) August 27, 2025
Join Chase to experience the insane power of realme 15000mAh Concept Phone! pic.twitter.com/htm9bFNzLi
Realme says this phone can handle up to four days of standard use without hitting zero. If you’re a video creator (or just love a binge session), you’ll be happy to know it can record 18 hours of video or play silent video for more than two days straight. We still don’t have official details on charging speed, but with a cell this size, it’ll need something like 100W fast charging at least just to keep things practical.
The transparent aesthetic isn’t just a gimmick. Realme’s design makes the battery and main components visible through a translucent grey shell, carrying forward their “Explore” theme and showing off the tech that usually gets hidden. Even with all that battery, you get a modern, slim-feeling device that doesn’t scream “power bank with a screen.” Underneath, there’s a dual camera setup and a MediaTek Dimensity 7300 chip (at least for this early concept), but final specs might change if it ever hits the market.
For now, this is just a concept, but if Realme brings it to India, the days of panicking about your charger—or lugging around a chunky power bank—could be finally over.