KUXIU’s new S4 power bank introduces semi-solid-state chemistry into the premium portable charger market, offering enhanced safety features, innovative design, and high performance , but at a premium price.
KUXIU’s S4 arrives at a moment when battery safety is drawing more attention, particularly on aircraft, and it is one of a small but growing number of power banks built around semi-solid-state chemistry. That approach replaces much of the liquid electrolyte found in conventional lithium-ion cells with a gel-like material, which battery explainers say can reduce the risk of thermal runaway if the pack is damaged. It is still an early market, though, with higher costs and limited availability keeping these devices firmly in the premium category.
On design alone, the S4 is meant to stand apart. It uses an aluminium alloy shell, comes with a braided USB-C cable and adds features that are still uncommon on portable batteries of this size: a fold-out kickstand, a bright information display and support for both wired and magnetic wireless charging. KUXIU offers it in black and a vivid orange finish, while the company’s claim that it is the thinnest 10,000mAh semi-solid-state model available reflects how aggressively it is positioning the product in a still-niche segment.
Performance is equally ambitious. The S4 supports up to 30W over USB-C and up to 25W wirelessly through Qi2.2, placing it above many basic magnetic power banks. The display shows battery percentage, output levels, temperature and battery health, while the kickstand is intended to keep a phone usable in either portrait or landscape mode during charging. KUXIU also supports pass-through charging, so the power bank can itself be recharged while simultaneously powering a device.
In testing described by Too Many Adapters, the wireless charging speed varied sharply by device. A Samsung Galaxy S24+ charged slowly because it lacks newer magnetic charging support, while an iPhone 15 Pro and a Galaxy S26 Ultra achieved far quicker top-ups when paired with MagSafe or a magnetic case. The review also found strong magnetic grip, useful heat monitoring and wired charging that reached nearly the full 30W ceiling on compatible phones, with the pack itself recharging in a little under two hours from empty.
The main obstacle is price. The review put the S4 at about $78, which is far above many standard 10,000mAh power banks, even if the extra spend buys a thinner chassis, higher-end materials, wireless charging, a stand and the promise of improved safety. That makes the S4 easy to recommend for users who want a premium magnetic battery and are willing to pay for the new chemistry, but much harder to justify for anyone who simply wants the cheapest way to carry backup power.
Disclaimer: This content is intended for informational purposes only. Readers are advised to exercise their own judgement, conduct due diligence, or consult a qualified expert before acting on any information provided.
