The internal resistance tester can measure the internal resistance and voltage of the battery at the same time. It adopts kelvin four-wire test clip, which can avoid the influence of contact resistance and wire resistance, and can make more accurate measurement. This product adopts intelligent control, liquid crystal display screen, at the same time implanted kalman filter mathematical algorithm, with high precision, high efficiency, low cost, light weight, energy saving and environmental protection and other advantages. Built-in 1000mah lithium battery, 5V charging, android phone charger can be used, very convenient. SI-IRP-3563 added serial communication function, free to provide powerful computer analysis software.