Swelling of zinc gel, measuring method and results

An investigation on the swelling of gels after the process of electrolysis has been described, in assessing whether the method is an adequate tool for predicting the performance of zinc powder in alkaline batteries. The electrolyzed gels are transferred to glass flasks or graduated cylinders for the determination of the increase of volume of the gels, caused by the gas evolved inside the gels. The results show that there is an important loss of gas if the gels are stored in open cylinders and that the amount of gas lost depends further on the amount of gel stored in the cylinder and the geometry of the graduated cylinder. The swelling test of electrolyzed gels does not help predict the performance of the relevant zinc powder inside primary batteries if the gels are stored in open cylinders. Also, the gels lose mass due to migration of zinc to the negative electrode or the electrolyte which results to the inability of starting gel mass calculation by a depth-of discharge and current and time.