I get a Stainless Steel Vacuum Flask with temperature showing on the top in LED. The temperature will display if I touch the top showing the temperature of water inside. But how does it work - be it using a cell battery?

 

Moderators note : removed double pictures

 

 

It will have a micro inside with a thermistor sensor.

 

After I google it, I did found that it use 3V Lithium Battery
https://www.pcone.com.tw/product/info/191029344847#ref=d_search_listdefault_2

But whether or not it works for a lifetime is very depending. Mine seems to stop working after one year. As there is no way to charge it, I firstly guess it gets power from some kind of vibration as it is a portable utensil. It seems to stop working twice, and I put it inside the refrigerator and it works again. And then it did not display again with my touching on it, I will have to put it into the refrigerator again.

I would like to find a way to reuse this LED display unit as a thermometer if possible.

P.S. 1
Here is a link to this product at youtube