I recently bought a fanless laptop mat for use with my Dell e4300. When sitting in the lounge with the laptop on my lap it gets a bit warmish for my comfort. The fact that my clothes block it’s cooling vents certainly doesn’t help.
These new thingies work on a very cool principal of thermodynamics. Normally when you pump heat into a material it’s temperature increases. If however that material is at a point where it’s phase changes (solid – liquid or liquid – gas), then until the phase change is complete, all the energy you put in will not increase the temperature of the material. This is known as the “Enthalpy of Fusion” and the “Enthalpy of Vaporization”.
The really nifty thing is that with the right material, it can take huge amounts of energy to change it’s state compared to simply changing it’s temperature.
Quoting from Wikipedia
The high heat storage capacity in the phase change from solid to liquid, and the advantageous phase change temperature of 32 degrees Celsius (90 degrees Fahrenheit) makes this material especially appropriate for storing low grade solar heat for later release in space heating applications. In some applications the material is incorporated into thermal tiles that are placed in an attic space while in other applications the salt is incorporated into cells surrounded by solar–heated water. The phase change allows a substantial reduction in the mass of the material required for effective heat storage (83 calories per gram stored across the phase change, versus one calorie per gram per degree Celsius using only water), with the further advantage of a consistency of temperature as long as sufficient material in the appropriate phase is available.
As such – it literally soaks up the heat without getting significantly warmer itself. There is a caveat though – once it’s adsorbed all the heat it can – it will start getting hotter along with the laptop. For this reason you can only use it for a certain number of hours before letting it cool down and “reset”. The manufacturer quotes 8 hours, however this would vary significantly depending on the power of your laptop, and the ambient temperature. Mine works fine for 3-4 hours. As my laptop only gets hot on one side, I can just turn it around to get twice as much use out of it.
They also have a dimpled surface to allow some air to the laptop, and mesh underneath to help keep some distance. They roll up, but aren’t super light. I wouldn’t bother travelling with mine as I don’t tend to sit with my laptop on my lap very often when away. I could see it being useful watching movies in bed where the sheets stop the ventilation.
The only issue I see is they do limit airflow somewhat, possibly making the laptop run hotter.
You can buy them online at the link below.
Recommended – 4/5 as I love thermodynamics and this is cool!