Temperature sensors are everywhere in new energy vehicles

New energy vehicles refer to vehicles with new technologies and new structures that use unconventional fuels as power sources (or use conventional vehicle fuels but adopt new on-board power devices), and integrate advanced technologies in vehicle power control and drive. . The types of new energy vehicles include pure electric vehicles, hybrid vehicles, and fuel cell electric vehicles. In recent years, the new energy vehicle industry has developed rapidly. Compared with traditional fuel vehicles, the biggest difference between new energy vehicles is the use of power batteries as power drives. Components used in automobiles are different from general civilian products, requiring high reliability and being able to withstand harsh environments such as high temperature, vibration, and shock.

Temperature sensors are ubiquitous in automobiles.

NTC (Negative Temperature Coefficient) thermistor is a simple temperature sensor. It is made of metal oxides such as manganese, cobalt, nickel and copper as the main materials, and is manufactured by ceramic technology. These metal oxide materials all have semiconductor properties, because they are completely similar to semiconductor materials such as germanium and silicon in terms of conductivity. When the temperature is low, the number of carriers (electrons and holes) in these oxide materials is small, so its resistance value is high.As the temperature increases, the number of carriers increases, so the resistance value decreases. The variation range of NTC thermistor at room temperature is 100~1,000,000 ohms, and the temperature coefficient is -2%~-6.5%. NTC thermistors can be widely used in temperature measurement, temperature control, temperature compensation, etc.

NTC thermistor has the characteristic of changing the resistance value with the change of temperature, and because the thermistor element has the advantages of no loss and no hysteresis, it is widely used in automotive air conditioning control circuits, detection of engine cooling water temperature, motors and other equipment Protection, liquid level monitoring and other aspects. The number of NTC thermistors assembled on luxury cars has also reached dozens. Let's take a look at where thermistors exist in new energy vehicles.

Temperature monitoring: NTC thermistors are mainly used in automobiles for temperature control of air conditioners, monitoring engine coolant temperature, intake air temperature, exhaust temperature, fuel temperature, oil temperature, seat heating, catalytic converter, etc.

Motors and circuit protection and control of automobiles: NTC thermistors are mainly used in central door lock devices, sunshade roofs, seat adjustment soft settings, windshield wiper motors, etc.

Liquid level monitoring: NTC thermistors are mainly used for brake fluid level monitoring, engine oil and cooling water level monitoring, fuel level monitoring, etc.

Heaters: NTC thermistors are also used to heat fuel.

The most important performance of an NTC thermistor is its lifespan. After withstanding various tests of high precision, high sensitivity, high reliability, ultra-high temperature, and high pressure, it still works stably for a long time.

An NTC resistor product must first have a long life in order to ensure the performance of other performances; and the excellence of other performances depends on the production process reaching a certain technical level, which makes the long life of NTC possible.

Many high-tech electronic products require thermistors to perform stable temperature control and temperature measurement functions under ultra-high temperature, ultra-high pressure and other harsh conditions. Most manufacturers blindly pursue the conventional performance of NTC thermistors such as accuracy, sensitivity, and drift value. , ignoring the life of the resistor, resulting in the NTC being unable to work for a long time and affecting the use of electronic products. In this way, all performances such as accuracy, sensitivity, and high temperature resistance become meaningless.