OnePlus takes endurance to the next level with record-breaking battery

The OnePlus 15 has officially been unveiled in China, confirming weeks of speculation about its enormous 7,300 mAh battery. The flagship phone is set for a global launch, including the UK, later this month. With OnePlus promising longer life, faster charging, and flagship-level performance, the question now is whether this could truly redefine battery expectations in 2025.

The battery is undoubtedly the headline feature. OnePlus has equipped the device with a 7,300 mAh silicon-carbon dual-cell unit — the largest ever seen in a mainstream premium smartphone. This setup is designed to deliver outstanding longevity, allowing users to go nearly two full days on a single charge under typical use. For comparison, last year’s OnePlus 13 offered a 5,400 mAh battery, making this a major leap forward.

Charging speed hasn’t been compromised either. The OnePlus 15 supports 120W wired and 50W wireless charging, promising to fill the battery from zero to 100 percent in just over 25 minutes. The company claims that even a five-minute top-up can provide six hours of video playback — a feature that could make a huge difference for users who are constantly on the move.

Performance-wise, the phone runs on Qualcomm’s latest Snapdragon 8 Elite Gen 5 processor. This chip brings improved efficiency, ensuring that the massive battery lasts longer even during intensive gaming or 4K video recording. OnePlus has also included its new HyperBoost AI Engine, designed to intelligently manage background power usage without compromising performance.

The display has been upgraded too. It features a 6.78-inch LTPO AMOLED panel with a 1.5K resolution and a 165Hz refresh rate. This ensures smooth scrolling, vibrant visuals, and adaptive power efficiency when lower frame rates are needed. Combined with the new battery, the experience aims to balance visual excellence with extended uptime.

Despite its battery size, the OnePlus 15 remains relatively slim at 8.1 mm thick and weighs about 211 grams. The company claims its redesigned carbon-fibre cooling system prevents heat build-up during charging or heavy multitasking, addressing a common concern with high-capacity batteries. Early testers in China have reported stable performance and low thermal throttling during gaming.

For the UK market, OnePlus is expected to launch both standard and Pro variants. While pricing is not yet confirmed, estimates place the base model around £700 to £750 — making it competitive against Samsung’s Galaxy S25 Plus and Google’s Pixel 9 Pro. If OnePlus maintains its usual value-first pricing, the device could become one of the best-priced flagships with a true endurance edge.

Battery health has also been addressed. OnePlus says the new dual-cell technology retains up to 90 percent capacity after 1,600 charge cycles — roughly four years of daily use. The firm also promises adaptive charging, which slows down overnight charging to reduce wear, a feature similar to Apple’s Optimised Charging.

While the specifications are impressive, there are still questions about real-world results. The enormous battery could make the phone slightly heavier than competing flagships, and regional variations might affect charging speeds due to safety regulations. However, early feedback indicates that efficiency optimisations in OxygenOS 16 help deliver longer screen-on times without overheating or lag.

In conclusion, the OnePlus 15’s 7,300 mAh battery is more than just a numbers game — it represents a shift in smartphone priorities toward endurance and reliability. For UK consumers who use their phones extensively throughout the day, it could be a genuine game-changer. If OnePlus manages to deliver consistent real-world performance, this may be the most well-balanced flagship of 2025 — combining speed, power, and lasting energy in a single, sleek package.