Patent ID: 8957637
Filing Date: 2015-02-17
Classification: H01M,Y02E

Abstract:
1. A shunt system for a stack of series-connected electrochemical units, the system comprising: shunt circuits, each connected between a positive pole and a negative pole of an electrochemical unit; a control circuit, arranged for sending a control signal to at least one of the shunt circuits to cause it to shunt the electrochemical unit between the poles to which it is connected; and control modules each having its own voltage reference, each of the shunt circuits belonging to one of the modules, each control module including plural shunt circuits and the shunt circuits belonging to one control module being connected between the poles of the contiguous electrochemical units, so that the control modules subdivide the stack into plural groups of electrochemical units, each control module including means for communicating with the control circuit, so that the control circuit can control the shunt circuits belonging to different control modules; wherein the shunt circuits are each associated with a voltage measuring means for measuring the potential difference between the poles of the electrochemical unit to which the shunt circuit is connected, wherein each control module includes a calculation unit arranged for receiving signals from the control circuit, and wherein the shunt circuits have a variable impedance which is controlled by the calculation unit according to the signals received from the control circuit, and the potential difference between the poles of the units with which the shunt circuits are respectively associated.