션트 전류 센서의 감지정밀도 향상을 위한 저항온도계수 및 열기전력 안정화

Abstract

Recently, due to the rapid development of electric vehicle and energy storage system, it is emphasized for battery management system to be needed and to be improved. BMS carries out various movement for optimization the use of the energy and safe use of secondary battery, these movement of BMS start at high wattage shunt fixed resistor which performs a function for detecting current among the BMS components. In addition, for the safe operation of secondary battery, the reliability of current voltage variation detected from shunt should be secured, and for corresponding characteristics, the quality of Temperature coefficient of resistance for BMS shunt and the quality of Thermo electromotive force all must be excellent. For these reasons, this study comes up with the stabilization plan for thermo electromotive force and temperature coefficient of resistance of BMS shunt resistor which is key to secondary battery operation. In this paper, we prepared metal alloy resistor with stable thermo electromotive force (thermal EMF) as well as low temperature coefficient of resistance (TCR) by adjusting manganese composition of 3 to 12 wt% in the Cu-Mn-Ni alloy. Composition of the metal alloy fabricated was investigated using energy dispersive X-ray (EDX) analysis. TCR of each sample was measured as 44.56, 40.54, 35.60, and 31.56 ppm for Cu-3Mn-2Ni, Cu-5Mn-2Ni, Cu-10Mn-2Ni, and Cu-12Mn-2Ni, respectively. All the resistor samples were available for the F grade (±1% of the allowable error of resistance) high precision resistor. All the samples satisfied the baseline of high thermal EMF (under 3 mV at 60 oC), however Cu-3Mn-2Ni and Cu-5Mn-2Ni could satisfy the baseline of low thermal EMF (under 0.3 mV at 25 oC). Finally, we could design and fabricate the metal alloy resistor of Cu-3Mn-2Ni and Cu-5Mn-2Ni with low TCR and stable thermal EMF at the same time.