Post Comp 25' Considerations
This is a short summary of some issues we found needed addressing after Comp 2025 and how we plan on fixing them next year.
Cells
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Cells might have gotten too hot — could be bad thermistors, but either way the thermistor data shows a clear upward trend, meaning we ran hotter than we’d like
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Tim pointed out we’re drawing a much higher percentage of the discharge rating than before
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Might be worth switching to cells with higher continuous discharge ratings
Conclusion:
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8p36s configuration with molicel p50b best for longevity of future packs. This way there is no need to change s,p configuration considering extremely high discharge current and max voltage of MC.
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Re-test thermistors to confirm accuracy or buy new ones
Second Story
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Some boards have odd bases and inconsistent enclosures
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We should work with electrical to design one proper enclosure that fits everything
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This would let us move the battery pack contactors up to the second story
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Would also free up more space for better cell layout, leaving only fuse with the cells
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Cleaner wire harnessing becomes easier with one shared structure
Conclusion:
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Make the electrical assembly plate/box easily removable
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Ask electrical for a full wiring schematic of the assembly to plan out wiring harnessing
Module Design
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Module compression needs to be more reliable — more screws or better retention
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Thermistors need defined placement, possibly inside the cell holders
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Make voltage taps more accessible
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Improve general wiring management
- Maybe include wire clips in railing design
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Use Amphenol connectors to avoid relying on direct busbar connections
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Machine modules from Delrin for higher flexural modulus
Testing
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Plan timeline to include testing for next year. We don't want to be assembling the modules for the first time during June
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Get full discharge/charge curves to better estimate SOC starting on current pack and ideally on next pack before ASC 2026
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Get a better cell tester to fully characterize next cells