hydrogen production from water using solar cells powered nafion ...

CHAPTER IV
RESULTS AND DISCUSSION
4.1 Electrolyzer Manufacturing Experiences on a Single Cell Electrolyzer
Catalyst loadings, cell temperature, operating pressure, various membranes all affect
electrolysis efficiency as mentioned in the literature. To construct a properly working
electrolysis cell at an acceptable efficiency level, gasket material, flow field design, gas and
liquid delivery compartments and the compression level of the cell are also important
factors.
The works on the design of inner parts of the electrolyzers in the literature are not
given in details and usually did not mention about the compression level of the cell, gasket
material, the inside configuration of inlet and outlet gas compartments and the flow field on
the graphite layer. In this work, before investigating the performance of the solar power
driven proton exchange membrane electrolyzer, research effort was first focused on the
construction of a properly working single electrolysis unit.
The design of the cell was improved from experiences gained from the design at
hand. During these trials, the shape of the fluid flow field, gasket materials, compression
bolts, the formation of gas and liquid chambers were changed step by step.
Seven different electrolysis cell designs were tested. In these trials, water flow rate
was set to 2g/min while the temperature of the cell was kept constant at 30 o C. Identical
MEA and GDL were used while their active electrolysis areas were 20cm 2 in all these
experiments.
In the first trial, a graphite layer having an “X” shape flow pattern was machined as
shown in figure 4.1.
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