Australian tech brand Kuxiu has unveiled the KUXIU S2, the world’s first semi-solid-state external battery pack for smartphones—complete with MagSafe compatibility for iPhone users.

The compact 5,000mAh battery supports Qi2 wireless charging at up to 15W. With a capacity of 19Wh at 3.8V, it’s powerful enough to fully charge older iPhone models and deliver close to a full charge for newer devices like the iPhone 15 Pro.

What Is a Semi-Solid-State Battery?

Unlike traditional lithium-ion batteries, solid-state batteries replace liquid electrolytes with solid materials, offering better safety, higher energy density, and longer lifespan. Fully solid-state batteries are still rare and expensive to produce. However, semi-solid-state batteries—those using 5–10% liquid electrolyte—offer many of the same benefits while remaining more affordable. The KUXIU S2 uses a gel-like solid-liquid electrolyte mix, putting it in the semi-solid category.

Kuxiu lists the S2 as a lithium-polymer battery, traditionally known for lower energy density and shorter lifespan. But thanks to its semi-solid-state chemistry, the S2 delivers improved performance and safety. For comparison, typical Li-ion batteries may contain up to 25% liquid electrolyte, which increases the risk of leakage, overheating, and thermal expansion.

Key Features and Performance

Durability: Rated for over 1,000 charge cycles
Energy Density: 360 Wh/kg, an improvement over the 300 Wh/kg of conventional liquid-based cells
Form Factor: Slim and portable, measuring 10.4 x 6.7 x 1.0 cm and weighing just 145g
Charging Capacity: Provides up to 1.2 full charges for iPhones; in tests, it charged the iPhone 15 Pro to 98% before running out

Connectivity and Charging Options

The USB-C port on the S2 supports pass-through charging, allowing users to simultaneously power their iPhone and recharge the battery itself. It also supports bi-directional charging for non-Qi2 devices like Android smartphones and earbuds, offering up to 20W of output.

Price

The KUXIU S2 retails for around $80, placing it on the premium end of the power bank market, but justified by its cutting-edge technology and versatility.

Source