Magnetic sensors offer nondestructive way to verify battery authenticity

Recently, fires and other accidents caused by the use of non-original equipment manufacturer lithium-ion batteries (i.e., compatible batteries) have become a problem. However, these compatible batteries are difficult to distinguish from the original ones based on their exterior features.

Researchers at University of Tsukuba have developed a nondestructive method for identifying the authenticity of individual batteries by attaching a magnetic sensor to the battery casing and measuring the magnetic field generated by the associated battery.

The work is published in the journal Green Energy and Intelligent Transportation.

Lithium-ion batteries (LIBs) are widely used in smartphones, PCs, and electric vehicles, making them indispensable in our daily lives. With the widespread use of LIBs, their shapes have become standardized; therefore, distinguishing OEM batteries from the non-original ones based on their appearance has become challenging. Although marks, certification displays, QR codes, IC chips, etc., are used to identify original equipment manufacturer (OEM) batteries, they can be copied. Hence, developing identification methods based on electrical characteristics and internal structures is essential.

Researchers at University of Tsukuba previously developed a method for detecting fuel cell failures using magnetic sensors.

In this study, they applied this method and developed a system for identifying LIBs based on the differences in the current path caused by the internal structure of these batteries.

This method involves attaching a magnetic sensor to the exterior of an LIB and measuring the magnetic field generated by the current during charging and discharging. This simple method can identify single cells and multiple batteries connected in series.

The researchers will attempt to establish a system for identifying the battery within an actual battery module. Furthermore, they will also seek to develop a system that can identify batteries even in cases of deterioration and identical structures.