Spark Slim is… slim and with a big battery. | Image credit – Tecno
However, there’s a catch: this phone is still just a concept. No official launch date has been given, and while demo units will be on display at MWC, there’s a real chance this phone might never make it to store shelves as a real, commercially available product. After all, remember Tecno’s ultra-thin tri-fold concept from last year? Yeah, that’s still nowhere to be found.
The Spark Slim packs a 6.78-inch AMOLED display with curved edges, offering a sharp 1224p resolution and a smooth 144 Hz refresh rate. The company says it’s also impressively bright, reaching a peak of 4,500 nits, and includes a 13 MP front camera for selfies. The 4.04mm thick battery supports 45W fast charging, and while the camera bump adds a little extra thickness, the phone remains surprisingly compact.
The phone has a dual back camera setup. | Image credit – Tecno
Actually, at just 5.75mm thick, this device indeed stands out as a real engineering achievement, especially when you consider the huge battery inside. For comparison, the upcoming Galaxy S25 Edge is rumored to be around 6 mm thick and will reportedly feature a smaller 4,000 mAh battery.
Meanwhile, the iPhone 17 Air will likely measure around 5.5 mm at its thinnest but don’t expect it to pack a battery as large as this one. So, the question is, how did Tecno make this possible?
The answer lies in recent advancements in battery technology, specifically the adoption of silicon-carbon batteries. This new tech allows for higher energy density in a more compact design. For example, the OnePlus 13 used a similar approach to fit a massive 6,000 mAh battery without sacrificing its slim profile.
Tecno is set to reveal more about the phone at MWC, which starts next week, so expect more details soon.
