MWC 2025: TECNO showcases SPARK Slim, the thinnest 5,200mAh phone in the world

At the MWC 2025 mobile technology convention in Barcelona, Spain, TECNO Mobile showcased the SPARK Slim.

This is the TECNO SPARK Slim

A slim phone with big battery capacity

According to the company, this is the world's thinnest smartphone with a 5,200mAh+ battery at measuring just 5.75mm.

TECNO claims that this device pushes the boundaries of smartphone slimness while "delivering powerful performance".

A glossy back cover

The device features "futuristic and sustainable" materials designed to offer a refined yet ergonomic and smooth feel. In particular, it uses a fully recycled aluminum metal using an integrated die-casting process, and a stainless steel unibody construction.

It has a 6.78-inch 3D curved AMOLED display with up to 144Hz refresh rate, 1.5K 1224p resolution, and a peak brightness of 4,500 nits making it visible even under direct sunlight.

Inside, it is powered by an unspecified octa-core chip. As mentioned, it is just 5.75mm slim despite having a large 5,200mAh battery capacity to provide an all-day performance. Making this possible, TECNO used a slim 4.04mm thick high-density battery. Moreover, it comes with 45W fast charging via USB-C.

The camera module has a slight bump

In the camera department, it has a 50MP + 50MP dual camera with a dynamic light-band effect. In front, it uses a 13MP front camera for selfies and video calls.

However, note that this is a concept smartphone. It is a proof of concept that something like this is possible. There is no info if it will be ready for retail anytime soon, and what will the price be.

The TECNO MWC 2025 Barcelona booth is at Booth 6B11, Hall 6, Fira Gran Via.

What do you guys think?