http://www.mtaonline.net/~hheffner/ElectrolyseAC.pdf
Has been updated to Draft #6 to include the following:
FLOW-THROUGH PLATE DESIGN FOR AC DRIVEN ELECTROLYSIS
Figure 4 is a diagram of a partial cross section of central cell
elements in a multi-plate AC drive cell. In Figure 4 assume the
right side is the positive side, the left is the negative. Only the
outermost (external) plates are connected to the power then.
Figure 4 shows the equivalent of what would be two (internal) plates
and a separating barrier in an ordinary multi-plate cell, but which
are here in the form of assemblies which conduct the flow of
electrolytes and products. Here, for brevity, oxygen will be
considered the anode product and hydrogen the cathode product, but
any appropriate product from the given electrodes may be used.
The first plate equivalent assembly includes a catalyst coating (1)
on a porous conducting plate (2) internal to which is an electrolyte
flow including evolved oxygen (3) drawn through the plate (2),
adjacent to an internal gas separator plate (4), which is adjacent
to an upward electrolyte flow including evolved hydrogen (5) evolved
on coating (7) and drawn through the porous conducting plate (6),
which has a catalyst coating (7) facing the electrolyte gap (8). All
portions of this plate assembly are electrically connected conductors.
Adjacent to the electrolyte gap (8) is an assembly which is the
equivalent to a plate separator or barrier, and which includes a
porous high dielectric constant material (9) adhered to a porous
conducting plate (10) adjacent to a downward flow of electrolyte (11)
pumped into the cell through a manifold not shown. To the positive
(right) side of the fluid flow (11) is another porous conducting
plate (12) having adhered to it a porous high dielectric constant
material (13) through which the electrolyte flow (17) occurs into
the electrolyte gap (14). After the dielectric materials (9) and
(13) are adhered to the separator assembly, it is anodized in order
to electrically isolate all conducting surfaces from the
electrolyte. The two conducting plates (10) and (12) are
electrically connected, so the AC impedance between the separator
assembly and adjacent plate assemblies is primarily due to the
electrolyte in the gaps (8) and (14).
The second plate equivalent assembly includes elements 15-21 which
correspond exactly in name and function to elements 1-7. The fluid
flow inward (11) results in both hydrogen flow out (5) and oxygen
flow outward (17).
The plate and barrier assemblies are sealed against the dielectric
cell walls (22) in order to prevent conduction around the sides of
the plates. The first plate assembly bottom (24) seals the bottom of
the plate and makes electrical contact between the conductive
elements. Similarly, conductive bottoms (27) and (29) of the
barrier assembly and negative most (left) plate assembly seal their
bottom sides and make electrical contact between conducting elements.
Electrolyte fills all the internal and external gaps 8, 14, 23, 25,
26, 28 and 30, as well as saturates all the vertical plates except 4
and 12, which can be made of solid electrolytes, thus providing ionic
paths throughout the electrolyzer while separating gas flows.
Horace Heffner
http://www.mtaonline.net/~hheffner/
