iPhone 18 Pro's Redesigned Vapor Chamber Triples Cooling Surface Area

Could someone explain how the water cooling works? I am going to do some research but if someone knows how exactly that happens to work I am curious. Does it circulate the water? The article says cycles so assume so but how does it do that reliably? Hope this is not a silly question. Assume it's something to do with water vapor.

It's almost making a mini version of Earth's water cycle inside your phone. There's water in the chamber, and when it gets hot, it evaporates and moves to another part of the chamber to spread the heat. As the heat dissapates, the vapor condenses into liquid and goes back to the hot areas (using wicks/capillary action) to collect more heat. The idea is to spread the heat around your phone so the chip area doesn't get super hot.

Yeah, apparently they suddenly cracked the code in the last year and made it three times better than the previous vapor chamber. Revolutionary stuff. 😏

Poor 17 Pro owners though. LOL.

Why poor 17 Pro owners? We have a VC and my thermal performance is much better than 14 and 15 Pros I had. I can actually use it in the summer daylight without dimming and throttling. Plus I get to keep my glorious ornate color and still have top of line 12GB RAM for future proofing :)

Yeah, apparently they suddenly cracked the code in the last year and made it three times better than the previous vapor chamber. Revolutionary stuff. 😏

Poor 17 Pro owners though. LOL.

Couldn’t they use liquid nitrogen instead of water vapor? That should be cold enough

Wouldn't work. A vapor chamber is a heat spreader, not a refrigerator, so it can't make the phone colder than its surroundings.

To spread the heat (mostly to reduce the temperature of the A-series main chip and the RAM), the fluid inside a vapor chamber needs to be able to turn to vapor when heated above a certain temperature, and this vapor state allows it and the heat it contains to spread throughout the volume inside the chamber, spreading the heat over a larger area so it can be better dissipated through the outside surface of the phone's housing, and once it's lost enough of its heat when it reaches the parts of the vapor chamber where the temperature is lower, it needs to condense back into liquid so that the wicking material inside the vapor chamber can then carry the liquid back to the hotter areas and repeat the cycle. Liquid nitrogen wouldn't stay liquid in a phone since its critical temperature is about −147°C, above which no amount of pressure can keep it liquid. At room temperature it would become high-pressure gas, which would be a rupture hazard, and do nothing to spread the heat as well. Water happens to have just the right characteristics for a vapor chamber heat spreader.

It's almost making a mini version of Earth's water cycle inside your phone. There's water in the chamber, and when it gets hot, it evaporates and moves to another part of the chamber to spread the heat. As the heat dissapates, the vapor condenses into liquid and goes back to the hot areas (using wicks/capillary action) to collect more heat. The idea is to spread the heat around your phone so the chip area doesn't get super hot.

That sounds pretty cool (yes, pun fully activated) and really deserved more of a tech explanation during the event. I realise the majority of the target market won't care but first I've heard of this type cooling in a phone.

iPhone 17 Pro S