Battery Box Meeting Notes [MSXV]

Aux Battery

• Tested 25-ish cells (approx 60 total)

  • Probs finish testing after CAD deadline for 24

• CAD - need mount (will be late by few)

  • will upload to github EOD

• Cells may need balancing, will add balancing taps

Deliverable: Finish the CAD for the 24th

Enclosure

• Design overall → opening mechanism not optimal

• Will recad with bare min.

  • will host a design sprint with first years (sometime week)

  • optimize for air intake

• Box will rest on the floor of aero

• Shem → working on removal tool

• Manufacturing enclosure will have to wait

  • fireproof resin??

• top, bottom, holder will print (module)

• Ports have been found, need to confirm

  • Same as MSXII

• Wire gauge - ? 2-6 AWG?

  • hw → harnessing tell them (jenna)

  • high current speccing

• It was determined the module holders will be epoxied to the base of the enclosure

  • Reviewed w. Micheal the manufacturing process/considerations

Deliverable: Tuesday get a new timeline for the enclosure + Design review

Board Mounts

• Integration meeting happened, got lots of info for mounts

• AFE almost done, carrier and current sense not

• Ideal for current sense and carrier to be on top of each other

• Saturday → sprint for mounts

• Redesign, two brackets instead of two brackets and top plate

• AFE and carrier the same size

• Improve space for wiring, add standoffs for the mount

PVDR

• Use the MSXVII PVDR as much as possible

• Review Sunday 17th 7PM

Module Testing????

• Manufacturing state → as soon as possible

• Kostubh will draft a testing procedure for the pack to validate

  • Cell testing/validation → completed

  • Manufacturing guideline → test + revise as needed

• Will be there Monday to discuss

Coulomb Counting

• Telemetry moved to low-priority task

  • Discussed with integrations and will try to have all state of charge calculations local on the board itself

  • Driver can manually read out the state of charge via radio

• Looking into different integration methods for calculating SoC on STM32, should have some research by the next integrations meeting on Tuesday

  • Will be compared with IC board that Forest found to see which is more accurate

• currently doing research on viable algorithms and will be checking in with integrations on tuesday on our next steps based on the research

This week:

Apply for passes (HTN): shem, nicole, maggie, vaihbav

Nicole → rch session for first years

Summary: Got bodied but tight deadlines before manufacturing can proceed

Module

• add ribs to the L bracket of the module holder

• Make into one part

• Vertical mounts - make sure there is enough space/strong for heat insert

• Test the module to module connections

• Shift the hole to eliminate divet in plate

Cell Holder

• ABS → look into printing services (Micheal, WatIMake)

Busbars

• Only have sigma clad for module to module connections

  • Nickel to nickel for parallel + series connections

  • Due to spot-welding limitations

• Conduct resistivity test of connections

Module to Enclosure Design

• Hex caps MAY interfere with one another

• M3 may be too weak

• Find hardware to fit

Module to AFE

• Highest temp will be in the center

• Change number of thermistors to 24 → change layout

Manufacturing

• Test material resistivity

• No thermal test

• Need a way to measure ambient temperature (post manufacturing)

  • Strat will need this data

Electrical Connections

• Figure out a way, low prio, copper bar works for now

• Chaos

• New members starting to integrate (assigned to projects on Sat)

Production Module Testing (4.5.3)

• keysight: not feasible too long

• two paralle

possible solutions for worst case:

• ask other people? not done yet

• ask profs

• maybe past documentation

• ask teerstra

• ask lab in waterloo

• talk other design teams

• ask prof for battery challenge

Current assessment of module manufacturing & testing

• all modules to be completely manufactured: dec 8th

• will have to check with testing the first module

• do we have prototype module testing goals?

  • draw for 30min and check temperature

  • asc does not outline anything specific

Prototype module testing:

• depends on what we say

  • will say it was first one made (of the production run)

• documentation needed? no but yes (for future etc)

• keep prototype deadline same on pvdr but aim for end of nov

• continue to test for production

Pack & battery systems validation

• different equipment?

  • either use motor or power resistors

  • have a completed plan before jan 2024 (check-in mid-dec)

Actionables:

• module manufacturing timeline done for 06-11 (will check with donna)

• working on on validation plan - check monday 05-11 and review (check with owen)

• jenna will start prototype testing this week, feasibility test (check-in end of week)

  • just draw current 58.2 A and 3.6V with module