Current sensor has best-in-class charge measurement accuracy for Li-ion EV batteries

The CAB 1500 is the most recent member of LEM’s CAB series of automotive-grade design sensors that uses the properties of fluxgate transducer technology to provide the high accuracy and low offset needed for reliable coulomb counting – measuring the discharging current of Li-ion batteries to evaluate their state of charge. The series is renowned for compliance with the ISO 26262 functional safety standard (to automotive safety integrity level C) and easy application via a controller area network interface offering 500kbps.

Backed by this open loop fluxgate sensor – furnished with electronic mechanisms and software that ensure the levels of reliability needed by BMSs – can be busbar or panel mounted and combines best-in-class resolution up to 0.1% with the lowest offset and highest accuracy.

As well as providing an extended current range of up to ±1500A and compatibility with 800V applications to the IEC 60664-1 standard, the new sensor offers non-intrusive measurement for full galvanic isolation up to 2.5kV. Other features incorporate low power consumption VS shunt technology and 0.5% total error over temperatures from -40C to +85C.

Says Jérémie Piro, global product manager BMS and Battery Storage: “Accurate battery charge level measurement is a crucial factor in being able to maximise the autonomy range of electric vehicles, and design engineers will welcome this addition to LEM’s CAB family, which offers the kind of performance levels they require. The CAB 1500 uses fluxgate technology to deliver the best SoC estimations on the market for today’s advanced EV battery management systems and will play a key role in enabling electric vehicles to go further than ever.”