Thermoelectric generators

[mpharr2]

Any plans to replace electrochemical cells with external connections (batteries)  in future Fitbit devices that are worn by users with thermoelectric generators?

[mpharr2]

A thermoelectric generator (TEG), also called a Seebeck generator, is a solid state device that converts heat flux (temperature differences) directly into electrical energy through a phenomenon called the Seebeck effect (a form of thermoelectric effect). Thermoelectric generators function like heat engines, but are less bulky and have no moving parts. However, TEGs are typically more expensive and less efficient

[Rich_Laue]

As your fellow Fitbit user, we know as much as you do. 

I do know of one company that makes a watch tgat charges it's battery through the movement of the arm(device)

Another name some may know this as is a Peltier Device. These also work in reverse, where electricity can be used to cool or heat. An example would be the solid state cooler unit on a CPU or the drink cooler that plugs into a cars power port. 

One glucose pump manufacturer is looking at placing one of these under the skin. 

Since this technology requires a difference in temperature. The closer the air temp to your bodies temperature the less power will be released. 

BTW it probably would have been better to edit your original post. 

[DrMay322]

Thermoelectric generators have advantages that can later be used for household purposes as well. I prefer the use of such generators. It is these options that have saved my family and my home on those occasions when there were problems with electricity in the city. There were many such cases, so we decided to save money by using just such portable generators.

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