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Remove the top plate and use MG Chemicals 8800 to attach Sigma Clad to the top cell plate (the Sigma clad should align flush with the top cell plate holders)
Begin with measuring the materials in a 2-to-1 ratio of liquid A and B, respectively. Approximately, 2.5mL of A and 1.25 of B should be sufficient for this step.
Use the heat gun to apply heat to both liquid A and B to rid any air bubbles
Pour mixtures into the same container ensuring to scrape excess material from the side of the container to get as much as possible
Use heat fun again to briefly flash heat (not too long as the mixture will set faster after cooling)
Mix mixture for 2 minutes
Wait until the material has reached a viscous state that is easier to work with (still liquid but congeals together better than the freshly mixed liquid)
Gently place the mixture onto the top cell plate (preferably with a popsicle stick or something to apply)
Press on the Sigma clad to their according sides of the module
Use clamps to hold down Sigmaclad, placing popsicle sticks down across the material ensures more of the surface area of the Sigmaclad contacts the cell plate
Leave for a minimum of 2 hours before moving, it takes 24 hrs to fully set
Once finished setting, remove any extra material and wipe the sigma clad with rubbing alcohol to clean the surface
Attach standoffs to the bottom cell holder
Begin by using LOCTITE SF4769 on the interior of an aluminum standoff
Place LOCTITE 262 on the appropriate screw for the stand-off (6-32 Thread Size, 1/2" Long Bolt, refer to Master BOM to find it)
Screw together the connections using an allen key to make sure it is secured
Solder voltage tap wires onto Sigmaclad tabs after setting is complete
Cut 4 wires to ~1 ft in length
strip one end of all 4 wires
Coat the end of the stripped wire with solder
Add flux to the Sigmaclad tabs and begin heat up the tab
Melt a pool of solder of the tab
solder the wire and Sigmaclad together, important to keep the solder as clean and close to surface so it fits through the top plate cover later on
Heat shrink the connection with ~2 cm of heat shrink
Feed nickel voltage taps through the bottom plate in the following configurations, paying close attention to the holes in which the wires go into
Tape up the nickel strips so there is no contact with the cells and the strip
Place cells in the correct placement
Begin with filling the first parallel line with cells, positive side upwards. Positive ends of the terminal should be where the 3D protrusions (bumps) are on the 3D print
Place tape on the top of cells
Then place the 2nd pair of parallel cells.
For the modules located in the center, place thermistor on the center of the cell using kapton tape, ensure it is secure.
Push wires to side and continue placing cells in parallel groupings, continously taping up the top of the cells
Add top plate using the same bolt process in step 4
Spot weld the connections
Refer to the Spot Welding guide to use the Spot Welder
Cover the Sigmaclad with electrical tape
First, spotweld the cells in parallel
measure out the nickel strip needed by laying the nickel across the parallel direction and making indentations where the cell holes are located. This is not enough current to be dangerous but to be extra safe, there are electoral taped bolts that can be used, this also creates more accurate strips
Spot weld the parallel connections until completed
Continue to do so for the series connections, making sure to solder the voltage taps in the appropriate places (shown below)
Potting material in the top and bottom
Measurements for the mixtures need to be determined first
Place the top cover on the top cell holder
SIDE NOTE:
Soldering Nickel:
5 total voltage taps:
4 nickel strips with 1 wire attached, 1 nickel strip with 2 wires attached
Solder them to the center and fray wires before soldering making sure to make the connection as low as possible
6 wires @ ~45cm or 1 1/2 feet, need to order more
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, using LOCTITE SF 424 on the M3 bolts.
TO BE CONTINUED