Energy Storage, 2nd Edition

Appendix 2:Aids and Supplemental Material

This appendix contains a collection of material that is relevant to the subject matter of this book. It is intended as a working aid and supplement to the information in the body of the book. The usual lists of the chemical elements, periodic table, electromotive series, etc., that are found in many scientific texts have not been provided because they are readily available in many sources.

A2.1 Properties of Homogeneous Membranes

A series of experiments were performed with five samples of ion transport membranes. Ion exchange membranes have proven to be the best means of reducing diffusion between two compartments of a dual liquid electrolyte cell. These tests were directed at determining the diffusion rate of molecular bromine in a NaBr solution. The relative electrical (ionic) conductance of these membranes was also measured.

A2.1.1 Diffusion Tests

Two 250 ml glass flasks with side tubes were employed per test setup. A membrane sample was placed over the flat ground mouths of the flasks with an RTV sealant. Two flasks were brought together, mouth-to-mouth, with the side tubes facing upwards. Both flasks were then filled with 250 ml of 2 molar NaBr solution. Free bromine was introduced into one of the flasks to make a 1/8 molar solution of Br₂. Five such setups were made, one for each of the membranes.

The start times of the tests were recorded. A titration solution of N sodium thiosulfate was prepared to measure the bromine in the ...