Best Semi-Solid-State Power Banks in 2026: Every Option Compared

Semi-solid-state power banks have gone from one product to an entire category in under a year. BMX SolidSafe, KUXIU, Momax, and Statik all sell magnetic power banks built with semi-solid-state battery cells - the kind that replace most of the flammable liquid electrolyte found in traditional lithium-ion packs with a gel-like substance that is far less prone to thermal runaway. The safety improvement is real. But the products themselves are not all the same.

We make SolidSafe, so we are obviously not neutral here. But we also know this category better than anyone, and we think the best way to earn trust is to put every product on the table and let the differences speak for themselves. We compared every semi-solid-state power bank currently available across the features that actually affect your daily experience: design quality, wireless speed, display information, cable convenience, charging versatility, color options, and port count.

Jump to: What BMX Recommends  |  Jump to: SolidSafe Air

What Makes a Power Bank "Semi-Solid-State"?

Traditional lithium-ion power banks use liquid electrolyte - typically 60-90% of the cell's interior. That liquid is flammable. If a cell is punctured, crushed, or short-circuits internally, the liquid can vaporize and ignite. This is the mechanism behind the battery recalls and airline incidents you have read about.

Semi-solid-state cells reduce that liquid content dramatically. BMX's SolidSafe cells contain approximately 2.5% liquid, replaced with a viscous gel-like electrolyte that does not flow or vaporize the same way. The result: damage is less likely to escalate into a fire. Every brand in this roundup uses some version of this chemistry, though the exact liquid content and cell construction varies. No battery is completely risk-free, but the reduction in flammable material is a meaningful engineering improvement.

The Brands

BMX SolidSafe (Singapore/Los Angeles) launched its 5K and 10K power banks in late 2025 after a successful Kickstarter, followed by retail availability and press coverage from Tom's Guide, TechRadar, and AppleInsider. The SolidSafe Air - a 6.8mm titanium model that won a TechRadar Best of CES 2026 award - launches in early 2026. BMX was founded by the team behind Hyper, a well-known mobile accessories brand. SolidSafe is the core product line, and BMX specifies its cells at approximately 2.5% liquid content.

KUXIU (Australia) was first to market with the S2 in early 2025 and later added the S3, a 10,000mAh model with a kickstand and built-in cable. KUXIU has strong review coverage from MacRumors, Macworld, and The Verge.

Statik (USA) sells a single 5,000mAh model. The Statik State Power Bank launched in mid-2025 and has been reviewed by Macworld and The Gadgeteer. Statik is primarily a cable and accessories brand; the power bank is its first entry in this category.

Momax (Hong Kong) entered the semi-solid-state space in January 2026 with the 1-Power S.Pass2, a 10,000mAh model with Qi2 25W wireless charging. Momax is a well-established brand (founded 2003) with Red Dot Design Award recognition.

Full Comparison Table

This table captures the specs. But specs alone do not tell you which one to actually buy. The differences that matter most show up when you look at how these products handle real daily use.

SolidSafe 5K $59.99 Shop SolidSafe 5K

SolidSafe 10K $79.99 Shop SolidSafe 10K

Design and Build Quality

A power bank magnetically attached to the back of your phone is not hidden in your pocket or bag. It is visible every time you use it. Design matters here more than in almost any other accessory category.

BMX SolidSafe power banks are built with a unibody aluminum enclosure. The LCD display sits flush, and the built-in USB-C cable doubles as a lanyard so it's always accessible. Four finishes (Black, Blue, Silver, Orange) match the current iPhone lineup.

The SolidSafe Air strips things down further: a titanium enclosure at 6.8mm thin and 116g, making it the slimmest in the category by a wide margin.

The KUXIU S2 combines aluminum with a Gorilla Glass back panel, which gives it a distinctive look and premium feel. The S3 also uses glass alongside aluminum and adds a kickstand mechanism. 

The Statik State is a straightforward aluminum power bank available in Black, Orange, and White.

The Momax S.Pass2 uses a metal frame with tempered glass. The mixed-material construction gives it a different look from the all-aluminum options.

SolidSafe's enclosure is CNC-machined from a single block of aluminum — a unibody construction you almost never see in power banks. The result is a seamless shell with no joints or visible hardware. Snapped to the back of a phone, it looks like it belongs there

Display: Why It Matters More Than You Think

The display on a power bank is not a luxury feature. It is the difference between knowing exactly what is happening with your charge and guessing.

BMX SolidSafe power banks use an LCD screen that shows two things: your exact remaining battery percentage and the real-time wattage being delivered to your device. The percentage tells you how much power you have left. The wattage readout tells you how fast your device is actually charging right now. You can see the wattage climb when you plug in, watch it settle as your phone negotiates its charging speed, and watch it drop as your phone approaches full. If your wattage looks lower than expected, you know immediately - maybe you need a different cable, or your phone is already nearly full.

The KUXIU S3 has a digital display showing battery percentage and charging status, but no live wattage readout. You know how much power is left, but not how fast it is going out.

The KUXIU S2 and Statik State both use four LED dots. Four dots lit means somewhere above 75%. Three dots means somewhere above 50%. Two dots could be 26% or 49% - you genuinely do not know. When you are trying to decide whether to grab your power bank before heading out, that ambiguity matters.

The Momax S.Pass2 product pages do not prominently feature a display, though the unit has indicator lights.

Bottom line: If knowing your exact power level and real-time charging speed matters to you, BMX SolidSafe is the clear choice - and it offers this on both the 5K and 10K models, not just one SKU. The SolidSafe Air uses LED indicators instead of an LCD, trading display detail for its 6.8mm profile.

Built-In Cable: The Feature You Do Not Appreciate Until You Need It

Anyone who has owned a power bank has experienced this: you have the battery, but you do not have the cable. It is sitting on your desk, or in your other bag, or tangled somewhere in a drawer.

BMX SolidSafe power banks include a built-in USB-C cable that doubles as a lanyard. The lanyard is permanently attached — it's always there for carrying on your wrist or clipping to a bag strap, which is genuinely useful at airports and events. The cable snaps into the lanyard, so when you need to charge something wired, you pull it out and plug in.  

The KUXIU S3 also has a built-in USB-C cable that tucks into a channel around the body. The Macworld review noted that the S3's cable can be completely removed — a different approach, but same trade-off.

The KUXIU S2, Statik State, and Momax S.Pass2 don't include built-in cables. They ship with a separate cable in the box.

Dual USB-C Ports: Charging Two Wired Devices at Once

The BMX SolidSafe 10K is the only semi-solid-state power bank in this comparison with two independent USB-C ports. That means you can charge two wired devices simultaneously - say, an iPhone and an iPad, or a phone and a pair of earbuds - without needing a wireless connection for one of them.

Every other model in this roundup has a single USB-C port. The KUXIU S3 and Momax S.Pass2 can charge two devices simultaneously, but only by using one wired and one wireless connection. That works well for phones with MagSafe, but it means you cannot charge two devices that both need a cable.

For the 5K models (BMX SolidSafe 5K, KUXIU S2, Statik State), single-port is standard and expected at that size. But in the 10K category, the SolidSafe 10K's dual ports are a genuine differentiator.

Bottom line: If you regularly charge more than one device and want the flexibility of two wired connections, the SolidSafe 10K is the only semi-solid-state option that offers it.

Color Options and iPhone 17 Pro Matching

Apple's iPhone 17 Pro comes in exactly three colors: Silver, Cosmic Orange, and Deep Blue. It is the smallest color selection for a Pro model since the iPhone XS.

BMX SolidSafe power banks come in four colors: Black, Blue, Silver, and Orange. That covers all three iPhone 17 Pro colors plus Black as a versatile fourth option. If your phone is Cosmic Orange, your power bank can match. If it is Deep Blue, same. Silver, same. That kind of coordination matters when you are carrying a $1,199 phone and a power bank attached to the back of it.

KUXIU's color selection varies by model. The S2 comes in Black and Titanium. The S3 comes in Black only. Neither offers Blue or Silver to match the iPhone 17 Pro lineup.

Momax offers four colors (Yellow, Solar Orange, Black, Titanium) - good variety, but no Blue or Silver for iPhone 17 Pro matching.

Statik offers Black, Orange, and White - again, no Blue or Silver.

Bottom line: BMX SolidSafe is the only semi-solid-state power bank line that matches all three iPhone 17 Pro colors. The SolidSafe Air adds three titanium finishes (Titanium Black, Titanium Gold, Titanium Silver) designed to complement the iPhone Air lineup. If your power bank lives on the back of your phone, color coordination is not vanity - it is design coherence.

Build Materials: Glass vs. Aluminum

Most semi-solid-state power banks use aluminum construction, which is lightweight, durable, and handles everyday wear well. Aluminum dents before it breaks, and minor contact marks tend to blend into the finish over time.

The KUXIU S2 and S3 use tempered glass panels alongside metal frames. Glass looks premium, but it adds a durability consideration for a product that lives loose in bags, pockets, and on desks. The Momax S.Pass2 also uses tempered glass with metal.

The BMX SolidSafe and Statik State both use aluminum bodies without glass panels.

Bottom line: Glass and aluminum are both premium materials - it comes down to preference. Glass has a distinctive look and feel. Aluminum is lighter and more forgiving with daily wear. BMX and Statik use all-aluminum construction. KUXIU and Momax combine metal with glass panels.

SolidSafe Air: The Thinnest Semi-Solid-State Power Bank

The SolidSafe Air deserves a closer look because it represents something new in this category - a power bank whose defining feature is not what it adds, but what it removes.

SolidSafe Air is a 5,000mAh semi-solid-state power bank that measures just 6.8mm thin and weighs 116g - slimmer and lighter than most smartphones. It won a TechRadar Best of CES 2026 award, and it exists because of the same chemistry that makes the rest of the SolidSafe line safer. Traditional lithium-ion cells are limited in how thin they can be built because the liquid electrolyte needs containment volume. Semi-solid-state cells, with their gel-like electrolyte, can be compressed into thinner profiles without the same swelling and thermal risks. That safer chemistry is what makes 6.8mm possible.

The body is not aluminum. It is forged from titanium - the same class of material used in aerospace and high-end watch cases. Titanium is lighter and stronger than aluminum at equivalent thickness, and it dissipates heat efficiently. The result is a power bank that feels like a premium object, not a battery.

SolidSafe Air features Qi2 magnetic wireless charging and launches in three titanium finishes: Titanium Black, Titanium Gold, and Titanium Silver. The trade-off for that 6.8mm profile is intentional: Air strips back the built-in cable and LCD display found on the SolidSafe 5K and 10K. This is a different tool for a different job. The 5K and 10K give you the most features. The Air gives you the least bulk. If you want a power bank that genuinely disappears into a passport holder or slim wallet, the Air is the one.

At 6.8mm with a titanium body and a CES award, the Air is the clearest example of what semi-solid-state chemistry makes possible that traditional lithium-ion cannot.

What BMX Recommends

SolidSafe 5K $59.99 For everyday iPhone carry. One full phone charge with Qi2 wireless, LCD display with real-time wattage, and a built-in USB-C cable that doubles as a lanyard. Four colors matching iPhone 17 Pro. Semi-solid-state cells (~2.5% liquid). 2-year warranty. Shop SolidSafe 5K

SolidSafe 10K $79.99 For all-day travel or multi-device use. Doubles the capacity, adds a second USB-C port for two wired devices simultaneously, keeps the LCD display and built-in cable. 37Wh - well under the 100Wh airline limit. 2-year warranty. Shop SolidSafe 10K

SolidSafe Air $59.99 For ultra-slim everyday carry. 5,000mAh, 6.8mm thin, 116g, titanium, Qi2 wireless. Trades the LCD and built-in cable for the thinnest profile in the category. Titanium Black, Gold, and Silver. 2-year warranty. Shop SolidSafe Air

What People Get Wrong About Semi-Solid-State Power Banks

Myth: Semi-solid-state means the battery cannot catch fire.
Reality: Semi-solid-state greatly reduces the risk by removing most of the flammable liquid electrolyte, but no battery technology is completely risk-free. The correct framing is "reduced risk," not "eliminated risk." Be skeptical of any brand that uses absolute safety language.

Myth: All semi-solid-state power banks are basically the same.
Reality: The cell chemistry is similar across brands, but the product design - display, ports, cable, materials, color range - varies significantly. Two power banks can use the same type of battery and still deliver very different daily experiences.

Myth: Semi-solid-state power banks are not worth the price premium.
Reality: If you use a power bank regularly, the math favors semi-solid-state. A conventional lithium-ion pack lasts 300-500 cycles. Semi-solid-state models last roughly 1,000 cycles. That is two to three times the lifespan, which more than offsets the higher upfront cost.

FAQs

What is a semi-solid-state power bank?

A semi-solid-state power bank uses battery cells where most of the liquid electrolyte found in traditional lithium-ion batteries has been replaced with a gel-like substance. This reduces the amount of flammable material inside the cell, which lowers the risk of fire if the battery is damaged. BMX's SolidSafe cells contain approximately 2.5% liquid, compared to 60-90% in conventional lithium-ion.

Are semi-solid-state power banks safe to fly with?

Yes. All the semi-solid-state power banks in this roundup are under 100Wh, which means they are approved for carry-on luggage on commercial flights. The reduced liquid electrolyte content actually makes them a safer choice for air travel compared to traditional lithium-ion packs.

Which semi-solid-state power bank has the best display?

The BMX SolidSafe 5K and 10K offer the most informative displays in the category. Both show exact battery percentage and real-time charging wattage, so you can see exactly how fast your device is charging. The KUXIU S3 has a simpler digital percentage display without wattage. The S2 and Statik use four LED dots, which only give a rough estimate. The SolidSafe Air prioritizes thinness over display and uses LED indicators.

Is 25W wireless charging worth it over 15W?

It depends on your phone and your charging habits. iPhones 12 through 15 max out at 15W wireless, so a 25W power bank offers zero speed advantage for those models. iPhone 16 and 17 can use the full 25W, but the speed difference is most noticeable in the first 30 minutes of charging (0-50%). After that, thermal management narrows the gap. If you prioritize features like display quality, dual ports, or a built-in cable, the BMX SolidSafe's 15W Qi2 covers most use cases well.

How long do semi-solid-state power banks last?

All brands in this roundup claim approximately 1,000 charge cycles before capacity drops to 80%. Traditional lithium-ion power banks typically last 300-500 cycles. That means a semi-solid-state power bank charged once per day could maintain strong performance for nearly three years.

Which semi-solid-state power bank is best for iPhone 17 Pro?

BMX SolidSafe is the best match for the iPhone 17 Pro specifically, for three reasons: its four color options (Black, Blue, Silver, Orange) match all three iPhone 17 Pro colors, the LCD display shows exact percentage and wattage, and the built-in USB-C cable means you always have a cable ready. For users who prioritize 25W wireless speed on the iPhone 17, the KUXIU S3 or Momax S.Pass2 are also strong options.

Do I need a 5K or 10K power bank?

A 5,000mAh (5K) power bank delivers roughly one full phone charge in real-world use (after accounting for conversion losses). A 10,000mAh (10K) delivers roughly 1.5-2 full charges. If you charge once during the day, 5K is enough. If you travel, have heavy phone use, or want to charge multiple devices, go 10K. If you want the slimmest possible profile and you only need one charge, the SolidSafe Air at 6.8mm and 116g is the thinnest option in the category.

What is the thinnest semi-solid-state power bank?

The BMX SolidSafe Air at 6.8mm and 116g is the thinnest and lightest semi-solid-state power bank available. It uses a titanium body and won a TechRadar Best of CES 2026 award. The ultra-thin profile is made possible by semi-solid-state cell chemistry, which can be compressed thinner than traditional lithium-ion without the same swelling risks.

The Bottom Line

The semi-solid-state power bank category is still young, but the options are already meaningfully different. Every product in this roundup benefits from the core technology shift: reduced flammable liquid, longer cycle life, and improved thermal stability.

Where the products separate is in the daily experience around the battery - the display, the cable situation, the ports, the materials, and the colors. Those are the things that determine whether a power bank feels like a thoughtful part of your setup or just another thing to charge. We built SolidSafe around all of them.