Note - this page is now outdated and requires updating for Rev 6.
Use:
Nickel strips are used in the battery modules to connect the battery cells to the busbars. They will be spot-welded to both parts.
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Width - 7 or 8 mm (design works with both, 8mm is ideal due to lower resistance)
Thickness - 0.1 to 0.15mm 127mm (either will work, thinner will allow for quicker spot welding - depends on availability)
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Amount Required:
Initial Information
| Strip Type | Number of Strips per Module | Number of Modules being Manufactured | Total Number of Strips Required |
|---|---|---|---|
| Short Nickel Strip | 12 | 30 | 30 x 12 = 360 |
| Long Nickel Strip | 6 | 30 | 30 x 6 = 180 |
Assumptions / Simplifications
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OTHER ASSUMPTIONS?
Calculations
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SHORT NICKEL STRIP
Length of strip = 75mm
Depth of bent areas = 1.25mm
Number of bent areas = 4
Length Required per strip = length of strip + (number of bent areas * depth of bent areas * 2) = 75 + (4 * 1.25 * 2) = 85mm
Length for short strips = 85mm * 360 strips = 30.6m
We need half as many long nickel strips as short nickel strips, but the long nickel strips are twice as long (following the same pattern). So just double the amount required from the short nickel strips.
Total length required = 30.6m * 2 = 61.2m
Add a safety factor of 1.5 or 2x
We should get around 100m of nickel strip
Weight of material:
Volume = 10000cm * 0.0127cm * 0.8cm = 101.6cm3
Results
HOW MUCH MATERIAL DO WE NEED?Nickel Density = 7.81g/cm3
Mass = 101.6cm3 * 7.81g/cm3 = 800g
Results
800g minimum should be ordered.
Source For Material:
We will likely source the material from Aliexpress due to its abundance. Care must be taken to ensure that the supplier is selling pure nickel, and not nickel plated steel. Endless Sphere Forums is a good place to look for official links.
Alternate sources are 18650shrink.com (a US based DIY powerwall store), Sunstone Welders.
ADD LINK TO MATERIALOrdered from here on Nov. 22, 2019:
https://www.aliexpress.com/item/32335859025.html?spm=a2g0s.9042311.0.0.24d84c4dVq3UMy
Manufacturing:
The nickel strips will come on a roll. They need to be cut and formed into the shapes required.
Jigs for both should be created to increase manufacturing speed. It may just be one jig that serves both functions.