“For the first time ever, a vapor chamber on Galaxy Z Flip.”
That’s the only mention of a vapor chamber cooling system inside the new Galaxy Z Flip 6 from Samsung in its press release. The on-stage presentation at the glitzy Unpacked event in Paris wasn’t too different either. One might mistake this approach from Samsung as a relatively tame upgrade. In reality, it’s anything but.
At the moment, a vapor chamber cooling kit is the most advanced and efficient kind of thermal management hardware inside a phone to handle the heat produced by a power-hungry battery and the battery while it is being charged or drained of power. Some phones, like the Nubia Red Magic, even fit a small fan like a gaming laptop — but that’s a rare outlier case.
The lack of a decent-quality thermal management kit can affect a phone’s performance in a tangible fashion. Look no further than the poor job done by Google on its Pixel phones, which have amassed infamy for running hot. But it’s not just the unpleasant feeling of a hot glass slab hurting your palm that’s the problem here.
Thermal throttling is a menace and it slows the entire system down. Warnings like “Device Cooling Down” on a phone’s screen aren’t just a benign system message. It changes how you interact with your phone for a short spell. Those changes include dimming the screen, slower performance, and reduced or paused charging.
While capturing high-resolution videos, I’ve often come across warnings telling me to close the camera app because the battery was running too hot. In the case of last year’s Galaxy Z Flip 5, the situation with an overheating phone was particularly dire.
It’s a phone that starts at a thousand dollars (or used to), packs a heavy-hitting flagship silicon, and aims to deliver a buttery-smooth performance. But it just couldn’t. From the barrage of complaints on Reddit and the Samsung Community forum, the lack of an effective vapor chamber cooling system inside the foldable phone caused it to heat, stutter, and shut down on some occasions.
According to users, the clamshell-style foldable phones from Samsung have a tendency to run hot while playing games, with the Android Auto interface open, charging, or with multiple processes running in the background.
My own experience with the Galaxy Z Flip 4 was filled with overheating-related frustrations, and it never went away. The problem worsened while testing beta versions of One UI, which can be blamed squarely on the lack of optimizations and software bugs raising hell.
Thankfully, the Galaxy Z Flip 6 seems to have addressed the heating problem by adopting a vapor-chamber cooling system. Samsung hasn’t shed any further details on the engineering behind the vapor chamber system it has fitted inside the Galaxy Z Flip 6, but given the unique design language of a clamshell phone, it certainly wasn’t straightforward.
Digital Trends’ Tushar Mehta wrote a fantastic test-driven explanation of how a vapor chamber assembly works inside a phone, and I highly recommend that you read it.
After running a wide range of custom performance tests, here’s what he wrote:
“Cooling mechanisms — of which the vapor chamber is the most crucial part — play a vital role in keeping the internal temperature of the smartphones under check. It also ensures the external temperatures of the smartphones are not too high, so holding them does not become a challenge. Both of these aspects have equal importance.
“High internal temperature can reduce the performance and have dire effects on the battery, while rising external temperatures can make a phone uncomfortable to hold. In some instances, if the internal temperature exceeds a certain point, the phone shuts automatically to cool down, which is also undesirable.”
The key takeaway here is that for the first time in its history, a Galaxy Z Flip-series smartphone won’t lead to a hobbled performance scenario. It can now truly flex its silicon muscles, thanks to Qualcomm’s Snapdragon 8 Gen 3 ticking under its glass and metal shell. I am also hopeful that the larger 4,000mAh battery will serve as a meaningful companion on the ride.
Samsung says the size of the vapor chamber cooling system inside the phone is 50% bigger than the one it parked underneath the Galaxy S23 Ultra’s chassis. That’s a mean feat of engineering. In retrospect, Samsung’s failure to put a vapor-chamber cooling system inside the Galaxy Z Flip series so far has been a bit of a perplexing enigma, one that severely undercut its image as a powerhouse that also bends in half.
