Sensing Technologies

A BMS must be able to accurately ascertain the state of the system.  Such predictive capabilities can only be as accurate as the information on which they are based.  Accurate current measurement is the backbone of any BMS. Errors – even and sometimes especially errors in measuring small currents – propagates in every calculation necessary for management of energy storage systems.

Many energy storage systems exhibit a very wide dynamic range of current and temperature.   Such large dynamic ranges make it impossible to accurately measure current, especially small currents, using today’s technology.   A shunt with a high resistance will be able to measure small currents, but when measuring high currents, it will overheat and consume significant energy.  If the shunt has a low resistance, it may be able to accurately measure high currents, but it will not be able to distinguish signal from noise in small currents.  Highly accurate Hall Effect sensing technology cannot work in a wide temperature ranges.

Phenomena such as the thermoelectric potential differences in contacts, (e.g. the Seebeck effect) cannot be ignored when measuring signals in the microvolt region.

Sendyne’s^® technology is a breakthrough in current sensing, allowing the use of microOhm shunts, with much smaller resistance than what is possible to use today.

Sendyne’s^® Digitally Assisted Analog data acquisition ICs contain innovative circuitry in its ADC designs, tailored specifically to the storage task. These ICs use algorithms and techniques that compensate for every micro phenomena that effects the accuracy of the measurements.

Quoted from Sendyne company website. For the original article, please refer to Sendyne's website: http://www.sendyne.com//Technology/technology.html