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Sometimes I have to leave my phone in a hot car and don't have any other options other than leaving it in a locked car in the summer heat. What are ways to keep the phone cooler and not overheat it or worse cause damage to the batteries, etc.

The other day I got a overheat warning on my iPhone after having to leave it in the car. What are some ways to prevent this?

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up vote 9 down vote accepted

Place the electronics that contain a lithium based battery in the shade and keep windows open a crack. If possible, place the vehicle in the shade or use light or reflective colored windshield shades to reduce the heat that stays in the car.

Usually the trunk (or a well insulated bag) will lag the passenger compartment many tens of degrees and warm up several hours slower than something in the main cabin.

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I'm gonna +1 regarding the shade. Even in the hottest climate, while things may get hot in a locked car, things out of direct sunlight (and out of the glovebox) don't tend to rise that much. I'd suggest just putting it under your seat. You can do what others have suggested and wrap it in cardboard or styrofoam, but keeping in an open space close to the ground is the best bet. – user10355 Mar 18 '12 at 0:42
Also +1, but also to add, that if light can hit it, and warm it up, then a potential theif can see it, and how hot the phone is becomes the least of your worries. – Graeme Hutchison Mar 21 '12 at 12:53
Good call I am now storing the iPhone under a seat and out of the iPod dock and out of the sunlight, heat etc... Seems to be working well even sans the insulation so far – MrDaniel Apr 6 '12 at 18:34
If a thief takes it, it's a different sort of hot phone. – Daniel May 23 '12 at 5:42

Coffee cups (with lid, of course)

The most flexible and cheap solution are coffee cups. These cups are usually designed to have insulating walls.

Insulation is the most effective way to prevent heat building up. You might want to prefer white cups, but it should not make much of a difference.

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Lighter cups would reflect the light, while darker cups would absorb the light. You'd want a lighter cup to keep the heat away, because it's not going to make the cup itself hotter. – Andrew Larsson Mar 21 '12 at 15:40
This is a totally awesome DIY solution to insulating something for a short time. I'd add bubble wrap and plastic wrap in two bags might also insulate in a pinch. – bmike May 23 '12 at 0:32
@AndrewLarsson Yes, of course! I have no idea how that mistake happened. – gentmatt May 23 '12 at 5:12
@gentmatt I thought about it for a while and compared it to a black box. Inside the black box gets hot because it takes the light from the outside, heats the walls, and then heats the air inside the box, because they're not in equilibrium. It's nice to see you fix that. I'd hate for someone to have something go wrong with their phone, because they used a black cup. – Andrew Larsson May 23 '12 at 18:00

Insulation, not only can it keep stuff warm for longer, but it can also stop stuff heating up in the first place. So anything that provides insulative properties, styrofoam cups etc can be used. Even a cardboard box.

The first rule of thumb is to keep the thing out of direct sunlight, and even if it's on a pocket or compartment, choose one that is also not directly shone upon.

Another thing would be to turn if off while unattended in the car. If you have left it in the car, you can't be actively using it, so turn that sucker off and save some battery while you are at it.

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The use of insulated material around some "smart" phones, such as styrofoam cups w/ lids (as mentioned here), could create enough heat from the phone itself to cause a fire; just as reports that have shown some sleeping owners have been known to accidentally smother the phone with nearby blankets and/or pillows while in bed, thus causing the igniting of a fire around it. But no one would likely be there to stop that dangerous situation in a parked vehicle.

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