Looking at a typical competitor’s solution to the problem of multicell pack management, it can be seen that a number of external components (circled in red) are required. To allow cell balancing, a dedicated FET switch is placed across each cell in the stack. When any given cell exceeds a specified threshold, the parallel FET is turned on to divert charge current around that cell. This allows the other cells to continue charging without overcharging the higher voltage cell. A dedicated microcontroller is required to control the operation of the balancing FETs. Beyond that, this circuit does not include all the basic functions required, namely power FET drivers, current sense, and temperature sense.