Realme has once again pushed the boundaries of smartphone innovation at its 828 Fan Festival 2025, showcasing two futuristic devices — a 15,000mAh battery smartphone and the world’s first “AC” phone with built-in cooling fan technology.

World’s First 15,000mAh Battery Smartphone
Realme claims this device is 42% slimmer (8.89mm) and 68% lighter than a traditional power bank with the same capacity. This feat was achieved by introducing a world-first all-silicon anode battery with 25% silicon content and the highest-ever battery density of 1200Wh/L.
Through advanced lamination and design engineering, the battery is just 6.48mm thick, making the phone surprisingly sleek for such a massive power reserve.
Impressive Battery Life and Performance
On a single charge, the phone can reportedly deliver:
- 18.45 hours of video recording
- 30 hours of gaming
- 50 hours of video playback
- 5.18 days of typical use
- Up to 3 months standby in airplane mode
The phone is also equipped with a 6.7-inch OLED display, MediaTek Dimensity 7300 SoC, 12GB RAM, and 256GB storage, alongside 80W SuperVOOC charging for faster top-ups.
Realme “Chill Fan” Phone: The World’s First “AC” Smartphone
Alongside the battery powerhouse, Realme also introduced the Chill fan phone, dubbed the world’s first “air-conditioned” smartphone. It combines:
- 7,700mm² vapor chamber cooling
- Fan-based heat dissipation
- Thermoelectric cooling (TEC) technology using semiconductors
This system reduces the core temperature by up to 6.2ºC, making it 2–3 times more effective than conventional cooling. The IceSense Ultra back panel even changes color from white to blue as the phone cools.
Availability
While the 15,000mAh phone remains a concept, Realme hinted that its 10,000mAh battery phone could debut commercially as early as 2026. The Chill fan phone’s mass production timeline, however, remains uncertain.
With these innovations, Realme is positioning itself as a pioneer in futuristic smartphone design, blending extreme endurance with advanced cooling technology.
