When it comes to the MagSafe power bank marketplace, it's largely a sea of sameness. Not this one. Kuxiu's S2 stands apart with its semi-solid state battery technology that promises enhanced safety and longevity, albeit at a steeper price than conventional alternatives.

Design and Features

The Kuxiu S2 is a sleek, compact Qi2 unit with a premium construction that has four key components: a magnetic wireless charging area on top, a power button on the side, a USB-C input/output port (braided USB-C cable included), and LED indicator lights that display battery level. The aluminum alloy frame is paired with matte Corning Gorilla Glass panels, and the pack feels like it can take a whack – though it's not impervious to cosmetic scratches, as a couple of weeks' reviewing attest.

At just 143g (5.04oz) and measuring 106 × 69.5 × 10mm (4.17 × 2.74 × 0.39in), it's impressively portable and lighter than an iPhone 16. That said, when attached to my iPhone 16 Pro, the battery extends slightly beyond the phone's bottom edge, creating a minor asymmetry that likely isn't an issue when paired with the iPhone 16 Pro Max. The cameras remain unobstructed, at least.


The S2 has a handy LED indicator system, with four lights showing battery levels: 4 LEDs (>75%), 3 LEDs (>50%), 2 LEDs (>25%), and 1 LED (>10%). When battery drops below 10%, a single LED flashes. There's also a special LED pattern – four lights flickering like a running light – that indicates Small Current Mode is active (more on that below).

The Solid State Difference

In a departure from traditional lithium-ion alternatives, the S2's headline feature is its semi-solid state battery technology. This design eliminates leakage, explosion, and combustion risks. Kuxiu claims the battery can survive nail penetration tests without catching fire or exploding – and based on the company's own dramatic demonstration videos, it continues to function even after such extreme damage.


Despite some confusion on the labeling (which reads "Li Polymer Battery"), Kuxiu confirmed that the S2 does indeed use semi-solid state technology. The solid electrolyte inside can be made from various materials, including polymers – making both claims technically accurate.

Performance and Functionality

The 5,000mAh capacity power bank supports both 15W wireless charging for the iPhone 12 through iPhone 16 series and wired charging at up to 20W via USB-C. The USB-C input specs show it accepts 5V⎓3A/9V⎓2.2A for charging itself.


The manual recommends a first-use procedure: discharging the power bank completely until it shuts off (0%) before fully charging to 100%, preferably with a PD fast charger for optimal speed.

There are three main charging modes: wireless charging (with MagSafe activation), wired charging for other smartphones, and a dedicated Small Current Charging mode. This special mode is activated by double-clicking the power button, and is designed specifically for low-power devices like earbuds and smartwatches that might not draw enough power to keep the bank from auto-shutting off. I had no problems drawing power to charge AirPods Pro via MagSafe and Apple Watch via the charging port.


In my testing with an iPhone 16 Pro, the fully charged S2 brought my completely drained phone to 97% before depleting – slightly less than Kuxiu's claim of "approximately 1.2 full charges." The 16 N52 magnets provide a reassuringly strong connection that maintains its grip even when slipped into a loose pocket or bag. If your iPhone has a non-MagSafe case though, the bank is eventually going to slip off.

One particularly impressive aspect is the thermal management. Some slim power banks can become alarmingly hot during discharge (especially at low charge levels), but the S2 remained noticeably cooler in my experience.

Longevity and Value

Here's where the semi-solid state technology really shines. While the S2's $79.99 price tag is approximately 60% higher than comparable liquid-based power banks from companies like Anker or EcoFlow, the longevity benefits are substantial. Kuxiu claims the S2 will maintain 80% of its original capacity after 1,000 charging cycles, compared to just 300-500 cycles for traditional power banks. That's potentially double or triple the useful lifespan.

The efficiency is equally impressive. A full discharge offers 18-19Wh capacity power output, which is excellent after accounting for conversion losses. Looking long-term, this efficiency combined with extended cycle life makes the premium price more palatable.

Summing Up

The Kuxiu S2 feels like a genuine step forward in power bank technology. The $79.99 price tag initially stings, but when you consider the potential for double or triple the lifespan of conventional alternatives, along with enhanced safety and premium materials, the value proposition becomes clearer. For those who frequently rely on portable power, the investment should pay dividends over time.

What's missing? A kickstand would be nice. Some users might also miss the iOS widget integration that was available in Kuxiu's previous S1 model. Due to Qi2 certification requirements, the S2 doesn't offer the satisfying iOS integration that Apple's own MagSafe battery pack provided – no special animation on the lock screen or appearance in the battery widget. Don't get me wrong, it works flawlessly. It just doesn't feel as "Apple-like" as some might prefer. But these are minor quibbles against what appears to be a genuinely innovative product. If safety and longevity matter more to you than saving a few dollars upfront, the Kuxiu S2 deserves consideration.

Where to Buy

The Kuxiu S2 Qi2 5000mAh MagSafe Solid-State Power Bank is available in black or natural titanium colors for $79.99 from Kuxiu's website and authorized resellers.
This article, "Review: Kuxiu S2 Power Bank - Semi-Solid State Tech Promises Longer Life, Better Safety" first appeared on MacRumors.com

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