Design and Batch Preparation of a High-Performance Temperature Sensor for New Energy Vehicles Using Platinum Film

With the rise of the new energy industry, the number of new energy vehicles is increasing year by year, however, the thermal runaway of lithium-ion (Li-ion) batteries is a tough problem. As a key component of the battery management system (BMS), a high-performance, interchangeable, and low-cost temperature sensor is essential to improve the safety of power batteries in new energy vehicles. In this article, a batch of platinum (Pt) resistance temperature sensors with ten kinds of line widths were prepared by using micro-electro-mechanical system (MEMS) batch microfabricating technology. After tests, these batch-prepared temperature sensors possess high performance, small size, and low cost. They showed extremely high linearity of resistance-temperature curves (
${R}^{{2}} >$
0.9999) and superior accuracy (
$< 0.3~^{\circ }\text{C}$
). Besides, the effects that came from MEMS technology were explored. The batch of temperature sensors showed excellent consistency of linearity and temperature coefficient of resistance (TCR), 99.99% and 98.89%, respectively. Furthermore, the temperature sensor exhibited excellent repeatability and stability. The coefficient of variation (CV) is only 0.31% for five repeated calibration experiments and the max temperature deviation is below 0.05 °C in stability tests. Temperature sensors with
$45~\mu \text{m}$
linewidth have the best interchangeability of all kinds with interchangeable temperature differences of less than 1.5 °C. All the results indicate that the batch microfabricated sensors are suitable for large-scale measurement requirements for Li-ion batteries in new energy vehicles.