Use of an Analytical Model to Enhance Understanding of Shunt Currents in a Bipolar Stack

An analytical model of shunt currents in a bipolar stack is presented. The analysis assumes linear kinetics and treats the stack as a continuum. The model results in three principal design equations: port current density, manifold current, and drain current due to shunts. These design equations use well-defined stack geometric parameters and physico-chemical properties and are suitable to introduce learners to the topic of shunt currents. The connection between corrosion and shunt currents is shown. The simplified model qualitatively explains the general behavior of corrosion, providing important insights. However, linear kinetics are not appropriate for accurate work detailing the susceptibility to corrosion. The role of the analytic model is to help newcomers develop an understanding and some intuition into the behavior of shunt currents.