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Let's analyze this problem from the perspective of efficiency and motivation.

From my experiments and referring to the technical report of the semiconductor thermoelectric generator, we can know that:

When the temperature difference is 80℃, the open circuit voltage is 4.8V, the power generation current is 569mA, and the power generation is about 2.7W W.

Assuming that the student's body heat charging treasure has obtained a certain voltage, a booster circuit is used to boost the voltage, and the general formula of the booster circuit is obtained:

Uout*Iout =Uin*Iin* efficiency

In order to adapt to the general mobile phone, the charging voltage is 5V, the charging current is 500mA, and the computing power is about 2.5W

((5V, 1A) marked on the charger refers to the nominal lower limit of its output power, which should exceed the demand of mobile phones-the actual charging current of most mobile phones is less than 500mA (USB2 specification). )

Pigeon line.

From the above analysis, it seems that the body heat charging treasure can be made in theory.

Wait, first of all, the hot end of my experiment is the method of heating the aluminum radiator with candles and cooling the cold end with circulating cold water to reach the temperature difference of 80℃. How did this classmate produce this temperature difference only through a built-in module and human body temperature?

Furthermore, I did 2.7W in the experiment, because I used a constant temperature source at both ends, and both sides were coated with thermal conductive silica gel, and the thermal resistance of thermoelectric power generation materials from two heat sources was quite low. In fact, as a product, the thermal resistance of both sides of the material depends on the packaging material and thickness of the product, the fluidity of the surrounding air and the thermal resistance of the skin. If the thermal resistance is large, only a small part of the temperature difference between the palm and the surrounding environment may act on both sides of the thermoelectric power generation material, so the power generation efficiency will be further discounted.

Secondly, the generated electricity must be lost through the booster module and other circuits, and the final output power must be less than the input power (Uout*Iout =Uin*Iin* efficiency).

The sustainability of power generation is also a problem. According to this classmate's method, you need to hold a body heat charging treasure for two hours to fully charge your mobile phone, which is inhuman, and most people in ordinary life will not toss themselves to charge their mobile phones like this, right?

(; ￣Д￣)

To sum up, I don't think it is feasible to charge a hot charging treasure in this body.

-

I just saw this news and I was really scared. My brain made up for the fire in My World. I have a picture of Kidney 5 in my hand.

(; ￣Д￣)。 I'm just doing the experiment of thermoelectric power generation these days. Let me bring my experiment up first.

According to the news, he should have made use of the Seebeck effect. If the efficiency is really that high, he is willing to contact him. )? )。 Seebeck effect, also known as the first thermoelectric effect, refers to the thermoelectric phenomenon that the temperature difference between two different electrical conductors or semiconductors leads to the voltage difference between the two substances. Simply put, it is to convert the temperature difference between the two sides of a semiconductor thermoelectric generator into electricity, and the efficiency is generally low now. In addition to military and aerospace projects that burn money at no cost, civilian use is still in the development stage and has been partially commercialized in Japan, Europe and America.

Here are two screenshots. The first is the doctoral thesis of Xiao Heng, Ph.D., from Chongqing University, "Research on the Structure and Characteristics of High and Low Temperature Semiconductor Thermoelectric Power Generation System", and the second is the master thesis of Ou Qiang, a master of Chongqing University, "Simulation and Experimental Research on a Thermal Switch Thermoelectric Power Generation System". From this, we can simply and clearly look at the general efficiency of thermoelectric power generation.

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