Electrical Management of Batteries

With electrical management of the battery, the input parameters of current, voltage, temperature, SoC, and SoH are used to control the charge and discharge processes. The following tasks must be fulfilled  

The targets of charging are (i) charge as fast as is practical (ii) avoid ageing (iii) periodie equalization of eells. Charge methods are described in Chapter 9 and are not diseussed here. 

The BMS features neeessary for discharge operation depend strongly on the applieation. The main task is to avoid overload and deep discharge. Either of these factors will reduce the life of the battery. In some applications (e.g., automotive), it is important to guarantee a special performance (e.g., starting). Therefore, discharging below a critical state must be avoided. 

Deep-discharge protection is provided in order to avoid life-reduction by overdischarge of the cells. Over-discharge, especially to the point of causing some reverse charge, must be avoided [28]. 

If there is no charge-equalizing circuit that operates during discharge [29], the cell/block voltages must be monitored and the discharge must be terminated if the worst-case cell voltage reaches the cut-off value. 

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