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Re:

Tim,

>I have been messing around with liquid-dielectric plate capacitors...
>
>Anyone else ever used or dealt with a plate capacitor configuration using
>a liquid as a dielectric.  I have been messing with using deionized NH4,
>deionized (distilled) H20, and glycerine.  Anybody have any better ideas
>for the liquid dielectric?

If you want a much higher specific energy, use an NH4/LOX system - BOOM!
Oops, wrong list, this isn't rec.pyro

>
>A liquid-dielectric capacitor would be quite configurable.  The temperature of
>the liquid dielectric effects the dielectric constant, plates are easily added
>, corona and flashover should not be to much a problem seeing as the entire
>assembly (conductor plate wise) is totally immersed in the dielectric (no need
>to mess with transformer/mineral oil on top).  Dielectric breakdown due to
>inconsistancies in molecular structure (such as with polyethylene) is not as 
>big as concern as with film capacitors.  Just some thoughts...
>
>Also has anyone ever tried using a better conducting electrolyte in salt water
>capacitors, does it improve performance any?  Here are some equivalent 
>conductances of some electrolytes:
>
>NaCl              120.65

        NaCl + H20 <-> HCl + NaOH

>CaCl2             124.25
>K3Fe(CN)6         150.7
>K4Fe(CN)6         146.09
>Ca(OH)2           232.9

>NaOH              240.8
will disolve an aluminum plate -> Al0H + H2

>HCl               415.80
not much effect on an aluminum plate.
>
>....above in 0.005 gram equivalents per 1000 cubic centimeters
>
>Hydrochloric acid appears a good choice, that is if you could keep it from
>destroying the electrode and wall of the vessel..:)
>
>Note that sodium chloride (table salt) is pretty low, I am sure their is a
>better choice for the liquid-conductor plates in "salt-water" capacitors.
>Question is does the conductivity of the liquid-plate electrolyte really
>make that big of difference in overall capacitor performance, or maybe I
>am just pissing in the wind...
>
>Comments anyone???
>
>Tim
>
Tim,
        Electrolytic caps use an electrolyte of ethylene glychol (sp) read
that as automotive antifreeze.
        An electric current is then applied to produce a layer of aluminum
oxide on the anode plate. The oxide is the dialectric. Try it, either as an
electrolytic cap for dc or as a conductor for an AC cap using a seperate
dialectric. You'll still get a corona because it's a conductor.

                                jim