Kuxiu, a notable player in the tech industry, has recently launched the S2 Qi2 5000mAh MagSafe Solid-State Power Bank, claiming it to be the "worlds safest" power bank. Priced at $79.99, this innovative device is designed to offer robust performance and enhanced safety features compared to traditional lithium-ion power banks.

Solid-state batteries are regarded as the future of energy storage due to their superior power, compactness, safety, and sustainability compared to their lithium-ion counterparts. However, the challenge of cost-effective mass production has led Kuxiu to develop a semi-solid state battery for its new power bank. This distinguishing characteristic is crucial, as the company asserts it is the first of its kind in the market.

The Kuxiu S2 supports Qi2 technology for 15W wireless charging and boasts a capacity of 5000mAh at 3.8V (19Wh), allowing it to fully charge smaller iPhone models. While the name "solid state" appears on the product, Kuxiu has clarified that it incorporates a semi-solid state battery, which is essential for understanding its capabilities.

Having used the Kuxiu S2 for several weeks, I can confirm its functionality, albeit without needing the extreme tests of puncturing or exposure to fire that Kuxiu has undertaken. The power bank performs as expected, but it raises questions about the terminology used in the battery industry.

The distinction between solid-state, semi-solid state, and quasi-solid state batteries can often be confusing. The term solid-state typically refers to batteries that utilize a solid electrolytean essential component for the transmission of electrically charged particles. The classification hinges on the amount of liquid electrolyte present. If the liquid constitutes 5 to 10 percent of the battery's total weight, it is generally classified as semi-solid state, while under 5 percent is designated as quasi-solid state. The Kuxiu S2 contains a mixed electrolyte that forms a gel-like consistency, confirming its classification as semi-solid state.

Interestingly, despite the label on the Kuxiu S2 stating "Battery Type: Li Polymer," the reality is that this designation can be misleading. Lithium Polymer (LiPo) batteries have been standard in power banks for years but typically suffer from shorter lifespans and lower energy densities. Kuxiu's design uses a solid electrolyte that can be derived from various materials, including ceramics and polymers, validating its claim of being a Li Polymer battery that also possesses solid-state characteristics.

To put the S2's advantages into perspective, a standard Lithium-ion battery found in many power banks contains over 25% liquid, which increases the risks associated with leakage, thermal runaway, and fire hazards. Although Kuxiu's power bank does not fully exploit the advantages of all-solid state technology, it represents a significant step forward in safety and efficiency. The semi-solid state design allows Kuxiu to mass-produce the S2 using existing manufacturing processes, which helps maintain affordability.

According to Kuxiu, the S2 can withstand up to 1,000 charging cycles before its capacity declines to 80%, significantly outlasting the typical 300 to 500 cycles associated with conventional power banks like those from Anker. While the Kuxiu S2 comes at a premiumapproximately 60% more than similar liquid-based alternativesit promises double the lifespan, providing better value over time.

In terms of energy density, Kuxiu claims an improved 360Wh/kg, compared to 300Wh/kg for conventional liquid cells. The S2 is compact and lightweight, measuring 10.4 x 6.7 x 1.0 cm and weighing 145g, making it highly portable compared to competitors such as EcoFlow, which offers a slightly heavier and bulkier model.

The S2 features 16 powerful N52 magnets that allow it to attach magnetically to compatible devices swiftly, providing an easy charging experience. However, while these magnets are strong and reliable, they are not invincible. After several weeks of use, my review unit has sustained a minor nick on its surface but remains functional.

Kuxiu states that the S2 provides approximately 1.2 full charges for an iPhone. During testing, it charged my iPhone 15 Pro to 98% before depleting. While some users might find the design slightly asymmetrical, particularly when used with larger devices, the S2 remains compatible with both MagSafe cases and non-MagSafe devices.

One of the standout features of the S2 is its bidirectional USB-C port, allowing it to charge connected devices simultaneously. Despite its slow charging time from zero to full (approximately 90 minutes), it provides impressive versatility, also allowing for charging of other USB-C compatible devices.

Another thoughtful feature is the low-current charging mode, activated by a double-tap on the power button, which enables the S2 to power smaller gadgets without shutting off unexpectedly. Although it lacks a kickstanda detail many competitors includethe S2 is available in both black and titanium colors, providing aesthetically pleasing options for users.

In conclusion, despite some marketing ambiguities, I find the Kuxiu S2 Qi2 5000mAh MagSafe "Solid-State" Power Bank to be an impressive product. Though it may carry a higher price tag than conventional power banks, its semi-solid state battery technology appears to offer enhanced safety and longevity, making it a worthwhile investment for tech enthusiasts.