Page Comparison

Pre-Meeting Notes:

• What is the current state of modules?

  • 9 modules manufactured1 aux battery manufactured?

    • series spotwelds first decreases resistance

    • hot glue thermistors to busbar (only top and bottom as they get hottest)

    • each module can have 3 thermistors (on top, easier to manufacture)

    • busbars are good conductors, MS14 had thermistors only on busbars. Busbars are better for catching any cell that heats up

    • 1 on each busbar and 1 on center cell on negative end (closer to jelly roll)

    • difference b/w sum of voltage taps and pack voltage (through multimeter) because of Vdrop from busbars Vtap position

    • Vtap positions on bottom of module are ok (placement is closer to some cells, but prob only ~1mv diff)

    • voltage drop may occur between voltage taps (resistance of busbar)

  • 1 tested w/ forest

    • quick test

    • access to HV room w/ big eload (chroma?)

• What do we need to do W24?

  • 9 modules + 4 5 spare modules manufactured and validated

  • Test 8 modules

  • 3 aux batteries

    • Testing: basic capacity test (full cycle + IR)

• Review Module Testing Plan with Micah

  • All modules should be at same SOC when testing IR

  • cannot use multimeter because of method

  • High current testing is most important

  • when making tests, what can we do if it doesn’t pass?

  • wouldn’t do balance test

  • do full discharge for max current test

  • when checking temperature, use temperature rise from ambient rather than absolute temperature

  • first pack test should be as controlled as possible (chroma e-load)

  • Extra test: look at voltage of each individual cell

  • Ideal pack testing

    • take bench outside with pack and array, discharge and watch array charge the pack

  • OR put the whole system together, see vehicle move, watch array charge

• Review Modules with Micah

  • Does he have any concerns with any choices we made?