Thermoelectric battery is a device that directly converts thermal energy into electric energy by using temperature difference. The output voltage is relatively low, and it usually needs to be connected in series to obtain a higher output voltage. If there is a stable power output, the thermoelectric battery will be very large, and it needs a continuous and stable cold source and heat source to maintain the power output.

Mobile phones and computers need a stable DC power supply, and the working current needs more than a few amperes. With such a high power demand, it is difficult for thermoelectric batteries to meet the power supply requirements, and the size will be large, and the portability will be poor, which is very inconvenient.