Calibration Module for Battery Management System of Medical Devices

One of the main problems encountered in the development of a mobile medical device is the organization of power supply. Widely used rechargeable lithium-ion batteries have significant flaws, forcing to use a specialized battery management system that protects the battery from working outside its safe working area, ensuring maximum performance. A calibration circuit was developed for testing and adjusting a battery management system in process of fabrication to compensate the offset and gain of measurement circuits of the voltage, current and temperature. The technical solution of the calibrator was based on the development of three sections: the communication, control and temperature, the voltage supply and the current supply section. The voltage supply module was a multichannel precision voltage reference that simulated the voltage of a battery cells. The developed current supply section ensured the formation of electric current with an error of no more than one percent. Calibration of the battery management system allowed lithium-ion battery to operate in the range of permissible parameters, which was determinant in reducing the effect of short battery lifetime and eliminated possible dangerous situations.

I. Introduction

One of the fundamental problems of a portable medical device is the organization of its power supply [1]. Any failure or malfunction in the operation of this unit may lead to undesirable consequences, for example, damage to the body or even the death of the patient [2–3].