i just realized that because each PV cell is itself a diode, it would be better to have ~12,500 of these 4 to 5V cells arranged in series, and ~.01 mm interlayer spacing, to bring it to the 50 kV range needed for the next pinch.
with total thickness 25cm, and average overlap of 1570 x 2000 mm, total capacitance would drop to a few dozen pF.
easiest way to manufacture is probably to grow the PN junction epitaxially onto one side of a continuous, 2 m wide by 20km length of foil, as you roll it up into a cylinder. a continuous process would yield an even thickness.
you’d want to pull out gases, and bake, to anneal it nicely, and finally cut through and insulate along its width, on one side, changing it from a coil into the final cylindrical PV battery.
a 15 kJ pulse would then raise 1.2 J on each cell