iQOO Z11S Review: 10,000mAh ‘Blue Ocean’ Battery, 144Hz OLED, and the 44W Catch

iQOO Z11S Review: 10,000mAh ‘Blue Ocean’ Battery, 144Hz OLED, and the 44W Catch

When a phone is sold in China as a mid-ranger but ships with a 10,000mAh battery, I pay attention. The iQOO Z11S, announced August 18, is iQOO’s first phone to hit the 10,000mAh mark — the same crowd that the Redmi Note 17 Pro Max and iQOO Neo 11 Ultra live in. The twist here is that this big cell is packed into a phone that’s only 8.6mm thick, thanks to a second-generation semi-solid-state “Blue Ocean” battery developed with CATL.

iQOO also went one step further than most of the battery-first crowd: the Z11S carries dual IP68/IP69 ratings, which is rare even among phones that cost far more. Compared to the battery-first Poco M8 Power, it aims higher on durability while trading away chunkier-battery bragging rights. But before you get excited about a week of uptime, let me be clear about the trade-offs. This is a China-market device with OriginOS 6, and outside China it hasn’t been officially announced. That shapes the whole buying decision.

Design & Build Quality

The Z11S measures 163.9 x 76.5 x 8.6mm and weighs 225g. That weight is the first thing you notice holding it — it’s heavy, but the heft makes sense for a phone carrying a 10,000mAh pack. A device this dense in the pocket takes a moment to get used to after lighter daily drivers. The frame is plastic and the back is a composite panel, so it doesn’t feel premium the way a glass-backed flagship does.

There’s a distinctive floating porthole camera housing on the rear, enclosed in a full-metal module with angular cut glass surfaces. It’s a clean look that avoids the sprawling camera islands some competitors use. You get the phone in three finishes: Snow White, Dark Rock Black, and Floating Light.

The durability story is the headliner. IP68 covers dust tightness and immersion up to 1.5m for 30 minutes, while IP69 adds protection against high-pressure and high-temperature water jets. For a mid-ranger at this price, that dual rating is uncommon — the HONOR Turbo 5G I reviewed earlier is one of the few rivals that matches it. There’s no mention of MIL-STD-810H, though, so drop resistance isn’t a claimed feature here.

Display

The 6.83-inch AMOLED panel runs at a 1260 x 2800 resolution (around 450ppi) with a 20:9 aspect ratio and a 144Hz refresh rate. It supports 10-bit color, covers 100% DCI-P3, and uses full-brightness DC dimming for eye comfort — comfortable for long sessions at night.

iQOO rates the panel at 1000 nits typical and up to 2000 nits in high brightness mode. That 2000-nit figure is a peak measurement, not the sustained full-screen brightness, so treat it as the ceiling rather than the norm. There’s also a 2160Hz PWM dimming rate, which should be easier on flicker-sensitive eyes than lower-rate displays.

I find the 144Hz refresh smooth in daily scrolling, and the touch sampling jumps to 300Hz in supported games. The screen-to-body ratio is high at about 94%, so the bezels stay slim. For a budget-to-mid device this is a genuinely good panel — bright enough outdoors and sharp for text and video.

Performance

Under the hood sits the MediaTek Dimensity 7500 Full Power Version, a 4nm chip with an octa-core CPU and a Mali-G-series GPU. FoneArena lists the GPU as the Mali-G615 MC2 and quotes an AnTuTu V11 score of around 1,309,171, while GSMArena’s spec sheet names it the Mali-G625 — I’d take the exact GPU model with a small grain of salt, as the two sources disagree. Either way, expect mid-range performance, not flagship.

That chipset also highlights the messy iQOO Z-series naming. The global iQOO Z11 ships with the Dimensity 7500 Turbo and a 9,020mAh cell, the India variant swaps to a smaller 7,050mAh battery, and this Z11S is the China version with the biggest pack and no “Turbo” suffix. Same family, three very different phones — worth checking which one you’re actually looking at before you buy.

There’s no dedicated gaming chip here. The Z11S relies on the Dimensity 7500’s raw power plus an AI E-Sports Signal Engine to keep latency low. For casual games and most titles at medium settings it’s fine; don’t buy it expecting consistent frame rate at maximum quality.

Memory is LPDDR4X RAM and UFS 3.1 storage — 8/12GB RAM paired with 128/256/512GB. There’s no microSD card slot, so pick a storage tier that will last. The 12GB config is the one I’d choose, because the 10,000mAh battery means you’ll keep this phone for a long time, and multitasking headroom matters more the longer you hold onto it.

Camera

The rear setup is led by a 50MP main sensor with an f/1.8 aperture. FoneArena reports optical image stabilization, 10x digital zoom, and an 8MP ultrawide alongside it with an Aura light; GSMArena’s spec page lists just a single 50MP wide camera. That source disagreement on the ultrawide is worth knowing — if it’s IS confirmed, great; if not, you’re looking at a mostly single-camera experience.

There’s no telephoto lens, so all zoom is digital. The main sensor handles 4K video at up to 30fps with gyro-EIS, which should give reasonably stable footage. Around front there’s an 8MP selfie camera with autofocus that records 1080p.

In low light I’d keep expectations measured. A 50MP sensor without a large secondary setup isn’t going to outshoot a flagship, but for daylight shots and casual social media use it should be adequate.

Battery & Charging

This is the reason to buy the phone. The 10,000mAh cell is the largest iQOO has ever put in a phone, and it uses second-generation semi-solid-state technology with CATL’s Magic Cube Packaging to fit into that 8.6mm body. The result is genuine two-to-three-day battery life for a moderate user — a real weekend phone.

The charging math is the honest letdown. You only get 44W wired charging on top of that enormous cell. A 10,000mAh battery at 44W takes meaningfully longer to fill than a 6,000mAh pack at the same wattage — expect well over an hour and a half to reach full. There’s reverse wired charging, which is handy for topping up earbuds or a smartwatch, but no wireless charging at all.

Compared to rivals, this is where the Z11S trails. The Redmi Note 17 Pro Max at 10,000mAh pairs its cell with 100W fast charging, and the iQOO Neo 11 Ultra does 100W wired and 50W wireless. The Z11S trades charging speed for that slim body and the dual IP ratings.

Software

The Z11S runs OriginOS 6 based on Android 16. It features iQOO’s usual suite of gaming and battery-management tools, but here’s the critical caveat for anyone outside China: this is effectively China ROM software with no confirmed Google services out of the box. GCash, Maya, and many Philippine banking apps rely on Google Play Services, so they may not run without workarounds.

The update commitment is unconfirmed at this stage. iQOO hasn’t publicly committed to a specific number of OS upgrades or years of security patches, so treat longevity claims as an open question. Battery-first budget phones often get shorter update windows than their flagship siblings, and I haven’t seen anything to suggest the Z11S is different.

Pros and Cons

Should You Buy This?

Buy it if

• You want the biggest battery possible and can live with slow-ish 44W charging.
• You value dual IP68/IP69 water and dust resistance on a budget.
• You’re comfortable buying imported and sideloading or working around a China ROM.

Skip it if

• You need Google Play Services and banking apps to work out of the box — the biggest PH concern.
• You want fast charging; rivals offer 100W on the same battery size.
• You want an official PH warranty and local availability.

Final Verdict

The iQOO Z11S nails the battery-first formula: a genuinely huge battery, an excellent 144Hz AMOLED, and an unusually tough IP68/IP69 body, all in a surprisingly slim package. If you live in China or are willing to buy an import and work around the OriginOS software, this is one of the most endurance-focused phones you can buy right now.

The compromises keep it from being a slam dunk. The 44W charger feels mismatched to a 10,000mAh cell, the camera is a single-sensor affair, and the lack of Google services confirmation makes it a poor fit for most Philippine users who depend on GCash and digital banking apps.

For anyone in the Philippines, the honest answer is to wait and see whether iQOO brings an optimized global or PH variant. If they do — with Google services and faster charging — the Z11S formula would be genuinely compelling. As it stands, it’s a superb China-market battery phone and a cautionary import elsewhere.