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idea is to use powder contained in tubs. the walls will have a perforated mesh whos holes angle up and out so that the powder cannot escape. Nickel wires will be placed in the powder to conduct out of the cell. -Contact area is not optimal - that's why they use liquid electrolyte?-MJ


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  • maximize 3d printing
    • utilize parametric customization
  • avoid complicated chemical processing
    • no nickel plating


  • powders are very likely to become airborne
    • internet has suggested that "black strap molases" was added to edison batteries
    • might try to mix in at different ratios to see what happens to consitency
  • add a couple super capacitors to get some cold cranking amps?
    • not sure if that would work but just an idea
  • two tubs with grid on four sides of each or shared center.
  • fins for surface area.
  • cages that snap in to the bottom of a tub shared by two cages.
  • might use a part of a sphere for the snap in idea.
  • tub lid
    • tub lid will need some sort of two pole terminal block
      • from cages below
      • to next tub or out for use
    • might need some sort of cover for uninsulated wires from cage
    • vent for gas?


  • need to make parametric for 10 tub battery
    • maybe input number of rows and columns so it can be a single row or two side by side
  • might move side spacers onto cages. 3 sphere divots. 1 middle top and 2 side by side bottom, flip on opposite face. 1 or 2 on non mesh sides.

lessons learned

  • 3d printing with layers most often leads to leaks
    • can sometimes hold but not reliably.
      • perhaps in the future print settings could be optimized
    • need to use a regular plastic container for tub
      • perhaps half gallon milk jug


single cell separated by a grid.


scad work


parametric code to produce stl files for custom sized 3d prints.



Nickel Hydroxide
Wikipedia - NiFe Battery

KOH corrosion

  • need to find out if ABS or PLA or other plastics will hold up to corrosion by the electrolyte




  • nickel hydroxide Ni(OH)2
    • 4.10 g/cm3

to research later

would liked to have an info for:
impact surface area has
calculate AWG output based on dimensions of cage and cells


Need to find a battery analyzer.



nickel, aluminum, brass?


supplier directory




  • internet sometimes suggests having 2:1 nickel hydroxide to iron ratio
  • initial charge
    • a few places have suggested that a short (30min) small charge happen 1 day before a full charge
    • couldnt find any info on why this would be


  • it is suggested to add graphite to nickel hydroxide
    • internet says 17% graphite
    • will try 85% nickel hydroxide 15% graphite to keep it simple
  • one source said graphite is mixed into the iron
    • havent seen that suggested anywhere else
  • its also suggested that layers of nickel flake were used
    • multiple layers were pressed with hydraulic force
  • internet suggests 20-30% KOH in electrolyte
    • tolerant of different amounts

version 1

1 cup dry Ni hydroxide powder
1/4 cup dry graphite powder
1/4 cup black strap molases
3/16 cup water

FDM watertightness

epoxy resin to seal surfaces

  • instead use common LDPE containers?