Which phone protects users against heat-related explosions better, a G2, a Surround or an iPhone 4?
If you get a Windows Mobile Phone 7 hot enough, will it explode in your pocket? Concerns over a lack of a thermal protection shutdown in WP7 have surfaced thanks to a stunt video posted on YouTube.
As you can clearly see in the video posted below, the WP7 HTC Surround never explodes. But it also never activates a thermal protection shut down, no matter how hot it gets. The video shows the HTC Surround, the G2 (4G) and the iPhone 4 tossed on a grill and set on fire. Check out this picture at 0:54. The other two phones have gotten hot enough to either turn themselves off, or offer a warning that they are overheating.
But the HTC keeps on working and drawing power — and that’s both curious and potentially dangerous. In the end, all three of them show their batteries catching fire — but that’s to be expected if a cell phone is literally set on fire. Nevertheless, the video, which has generated three-quarters of a million views since it was posted by PocketNow Videos on Friday, sparked a discussion on the XDA Developer’s forum.
If a device gets hot enough, can the lithium battery explode — or can other parts of it get hot enough to burn you? And does that mean you shouldn’t carry an HTC Surround (or maybe any WP7 phone) in your pocket on a hot day? (This question supposes that you have really hot pockets, or wear hot pants, or can just generally be considered hot in a region involving pockets.)
The answer is maybe, but probably not. As you know, many a vendor has had to recall their wares thanks to the potential of fires from overheating. Recent recalls include Toshiba and HP.
Then again, earlier this month, Underwriters Laboratories issued a research report on Lithium-Ion battery safety. You’ll be happy to know that battery makers are subject to a wide range of tests in order to certify that they’ve met standards set by international safety organizations, such as UL, NEMA, IEEE, BATSO. The safety bodies all require multiple heat tests. Most require crush, shock and vibration tests, among others, too.
On the other hand, the report also warns that certifying the battery as being safe only addresses part of the problem. The device can still be built in such a way that it taxes the battery and becomes unsafe … giving the users unpleasant and perhaps dangerous exposure to the battery charge.
The report says (PDF), “Lithium-ion batteries are typically marketed and sold directly to original equipment manufacturers (OEMs) as components to be integrated into end-use products. Because the OEM’s product actually controls these functions, product safety issues involving cell charging rates, discharging rates and reverse charging may not be adequately addressed by battery testing alone.”
