It’s Mobile World Congress this week, which means delving into the wild world of concept phones. Usually, these are flexible display devices that never see the light of day, but this year OnePlus has the “OnePlus 11 Concept” phone. This has a liquid cooling system called “Active CryoFlux.” We’ll try to figure this one out, but our first red flag is that OnePlus doesn’t go into detail.
It is worth noting that OnePlus has made several concept phones, which have never had a big impact on the company’s consumer products. One phone placed electrochromic glass in front of the camera lenses, making them invisible when not in use. Another phone would change colors. Neither feature ever made it into a consumer phone.
The OnePlus press release states that the system features a “piezoelectric ceramic micropump at its core, connected to pipelines that are separated between an upper and lower diaphragm. The micropump takes up an area of less than 0.2 cm², which enables cooling liquid to circulate around the pipelines without a significant increase. The weight and thickness of the OnePlus 11 concept.”
Those fancy blue lights on the back of the cooling system seem to be there and not just for looks. The press release says, “The clear back provides a great view of the Active CryoFlux pipelines at work,” which also happens to be illuminated. OnePlus also says, “CryoFlux active liquid flows around the camera like a halo,” so everything blue is cooling liquid, according to OnePlus.
Regarding the actual results of this system, OnePlus says, “In laboratory tests, Active CryoFlux has been shown to reduce the phone’s temperature during gaming by up to 2.1°C, improving the game’s frame rate by 3-4 degrees, or by 1.6°C during loading, shave 30-45 (seconds) from loading time.” Those numbers are not particularly significant. Phones throttle fast enough because of heat, and mostly deal with “cooling” going slower. OnePlus’ press release quote uniquely measures frame rate in “degrees”—I’m pretty sure they mean “frames”—and the margin of error in a benchmark is often 3-4 frames. Phones are heat constrained and usually deal with their passive cooling solutions by slowing down so they don’t overheat. Adequate cooling would make a phone much faster, especially for prolonged use, such as gaming.
The liquid does not seem to be go anywhere, which would explain why OnePlus cooling results are so scarce. Water cooling in PCs works by attaching a block of water to something hot, like your CPU or GPU, heating that liquid, and then transferring it to something that will cool it, usually a radiator with some fans behind it of. Is that actual cooling loop being replicated here? The phone has no discernible way to cool the liquid when it gets heated other than just passive cooling. There are no fans, as we have seen on some phones, and no radiator or other cooling apparatus.
It looks like a small amount of liquid at the same temperature is just flowing around there, which OnePlus hopes will dissipate heat as it moves across the back of the phone. It probably doesn’t help that the cooling system is trapped inside the phone by a glass panel, which is an insulator. OnePlus also doesn’t explicitly say that the liquid cooling is meaningfully connected to the SoC via a water block. It is not clear what components it is cooling.
Finally, some marketers decided to describe the design of the phone with “Glass Unibody”, which sounds like a complete nightmare concept for the durability of the phone. It seems that there is nothing to this claim other than marketing: There is still a metal frame around the phone, and OnePlus’ picture of the “unibody” seems to be a normal glass back panel. A “unibody” would actually mean making the back and frame of the phone out of one piece, with the individual electronics mounted on that piece inside the phone. Thankfully OnePlus didn’t hire a highly skilled glassblower or anything, and there doesn’t seem to be much more glass here than in the regular Onelus 11.