Reasons for cell tank breakdown caused by pinholes in the ion membrane
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In the recent instances of leakage in the cell compartments, upon disassembly it was found that there were pinholes in the membrane, which led to the breakdown of the electrode grids in those compartments. What causes the breakdown of the cell compartments every time pinholes appear in the membrane?
There are many reasons for pinholes to appear in membranes; firstly, it is due to quality issues with the membrane itself； Secondly, there are burrs on the electrodes ； Once again, it’s abnormal pressure and pressure differences ； Finally, there are impurities in the anode solution. In unit cells, pinholes in the membrane lead to the following: 1. Due to the pressure difference, the catholyte seeps through and corrodes the anode ； 2. The current density at the pinhole increases significantly, resulting in overload of the electrode current at that location ； 3. Due to the increase in current density, water electrolysis occurs at the pinholes, causing further damage to the membrane (no need to elaborate) ； 4. Over time, the pole plates in the cell slots will also become corroded, causing the observation holes in those slots to leak electrolyte ； 5. After pinholes appear in the membrane, the cell voltage first decreases (as the pinholes reduce the resistance); over time, the voltage begins to rise (as the electrodes corrode and the conductive area decreases)