Kuxiu S2 Qi2 Portable Charger Review: A Safer 5000mAh MagSafe Solid-State Powerbank for Those on the Go

Kuxiu S2 Qi2 Portable Charger Review

Over the last couple of years I’ve looked at a steady stream of MagSafe and Qi2 batteries. Most share the same basic formula: 5,000mAh, 15W wireless charging, 20W USB-C, a magnet, and a little plastic box. The Kuxiu S2 Qi2 Portable Charger takes a different path by bringing semi–solid-state battery tech into that familiar form factor. That shift isn’t cosmetic; it meaningfully changes safety, longevity, and how often the pack will need to be replaced. 

Against other mobile power gear I’ve used, the Kuxiu S2 Qi2 Portable Charger sits at the intersection of “daily carry” and “tech experiment.” It’s still a straightforward 5,000mAh MagSafe puck, but the semi-solid-state chemistry, Qi2 certification at 15W, and very slim 0.39-inch profile make it feel more like a next-generation reference design than a commodity accessory. 

What we like

Pros

• Semi-solid-state battery with higher safety and extended cycle life
• Qi2-certified 15W MagSafe wireless charging plus 20W USB-C PD
• Very slim, pocketable design (~0.39” thick, ~145g)
• Strong magnetic attachment for iPhone 12–17
• Maintains ~80% capacity after ~1,000 cycles
• Competitive discount pricing versus list

The move to a semi-solid-state battery is the S2’s defining feature. Kuxiu claims the pack retains roughly 80% of its original capacity after 1,000 full charge/discharge cycles, whereas conventional lithium-ion batteries typically start to sag after 300–500 cycles.  Semi-solid electrolytes also behave more safely when punctured, crushed, or exposed to heat, reducing the risk of swelling or fire. Independent durability testing that drives nails through these cells without catastrophic failure backs up the robustness story.  For a device that spends time in backpacks and travel bags (on planes), that extra margin of safety and longevity matters.

On the charging side, the S2 behaves like a modern MagSafe-style Qi2 pack should. It delivers up to 15W magnetic wireless charging to iPhone 12–17 models and up to 20W USB-C Power Delivery for wired output.  In practical terms, that means an iPhone 15-class device can go from near-empty to a meaningful top-up quickly over USB-C, while Qi2 wireless handles day-to-day top-ups on the go. The bank itself accepts up to roughly 20W over USB-C, refilling in around 90 minutes depending on the adapter.  That keeps turnaround times reasonable between outings. And the Qi2 feature means that it will also charge other items, like earbuds, that can fit neatly within charging area (even if they aren’t magnetic).

I like the industrial design more than I expected. With a 5,000 mAh capacity, a body around 0.39 inches thick, and about 145 grams, the S2 feels closer to a slightly thick iPhone case than a traditional brick-style power bank.  The flat-slab profile slips easily into a pocket or a sling without bulging, encouraging everyday carry rather than “only on trips.” The clean titanium finish aligns well with recent iPhone aesthetics, especially the natural titanium models.

Magnetic performance is another strong point. The Kuxiu S2 Qi2 Portable Charger uses a MagSafe-compatible ring and Qi2 alignment to clamp securely to MagSafe iPhones and compatible cases, resisting casual bumps in normal use.  For travel, that confidence matters: when the pack is attached, it tends to stay attached. The single USB-C port also supports pass-through charging, so the phone can stay on the S2 while the S2 is plugged into a wall charger, simplifying hotel-room cabling. 

Pricing is interesting. Kuxiu lists the S2 at $49.99, but it is frequently discounted on the official site to around $45, with similar street pricing at retailers like Amazon.  At the discounted level, it competes directly with mainstream 5,000mAh MagSafe competitors despite offering a more advanced battery. That combination of premium chemistry and mid-tier street price is one of the product’s biggest practical strengths.

What could be improved

Cons

• Only 5,000mAh: roughly one full iPhone charge
• Gets warm
• No built-in kickstand or multi-device charging pads
• “Solid-state” branding oversells what is really semi-solid-state chemistry
• Physically not a perfect visual fit on all iPhone sizes

Capacity is the most obvious limitation. At 5,000mAh (about 19Wh at 3.8V), the Kuxiu S2 Qi2 Portable Charger is designed for a single full charge on smaller iPhones or a substantial top-up on Pro Max-class devices, not for multi-day off-grid use.  For many people, that is enough, but heavy travelers who rely on navigation, a camera, and tethering will still want a second, larger pack in the bag. Kuxiu’s S3 addresses that with 10,000mAh, but that comes with more weight and bulk. 

Like many MagSafe power banks, the S2 gets warm while in use. I highly recommend recharging in the open with some airflow. Don’t bury it in a bag or a back pocket.

The feature set is also fairly minimal. Unlike some competing MagSafe batteries, the Kuxiu S2 Qi2 Portable Charger doesn’t integrate a kickstand or a display. But sometimes “nothing fancy” is just fine.

Marketing language around “solid-state” deserves critique. Technically, the S2 uses a semi–solid-state battery with a mixed solid-liquid electrolyte, not a fully solid-state cell.  The technology still delivers real safety and longevity advantages, but the branding can easily be misread as the all-solid future many people have been waiting for. I prefer clearer, more precise language on both the product page and packaging so buyers understand precisely what they are buying.

Fit and proportion on the back of the phone are functional but not flawless. The Kuxiu S2 Qi2 Portable Charger’s footprint doesn’t perfectly align with every iPhone size; on some models, it can edge into the camera bump area or sit a little awkwardly relative to the frame.  It doesn’t affect charging, but aesthetically and ergonomically, there is room for refinement, especially compared with OEM-aligned packs that mirror Apple’s curves more exactly.

Kuxiu S2 Qi2 Portable Charger: The bottom line

The Kuxiu S2 Qi2 5000mAh MagSafe Solid-State Power Bank is a thoughtful step forward for everyday mobile power. Semi-solid-state chemistry brings real-world benefits—higher safety margins, slower degradation, and longer useful life—without turning the product into a science project. Qi2-certified 15W MagSafe charging, 20W USB-C PD, and a very slim, pocket-friendly design make it easy to carry and easy to live with. 

The trade-offs are clear: modest capacity, minimal extras, some marketing overreach on the “solid-state” label, and a list price that only makes sense on sale. For people who want a compact, MagSafe-friendly, safer-than-average 5,000mAh pack that should last longer than conventional options, the S2 earns a spot on the shortlist—especially when picked up at its frequent sub-$50 pricing.  

Kuxiu provided the S2 Qi2 Portable Charger for review. Images courtesy of Kuxiu unless otherwise noted.

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