Nowadays, in the car industry, embedded systems have more important role, than before. The purpose of using these devices is to implement security, environmental friendly or comfort functions, as well as car diagnostic support. For example the battery sensors are one of those useful embedded systems. Its task is battery measuring, and transferring the data to other embedded systems in the network, which can use this information to their tasks. The Electric Battery Sensor (EBS) is battery sensor made by Robert Bosch Ltd. It measures the voltage, current and temperature of the battery, and estimates the state of it. With this information, its aim, to lower the fuel consumption, increase the lifetime of the battery. In addition, other extra functions can be implemented with this device.
Since the battery impedance greatly depends on the current state of the battery, the determination of the battery impedance give us important diagnostic information. The topic of the thesis is to develop a method to this embedded system which gives a solution, how this battery impedance can be estimated during using a battery in a car