Objective:
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Find the required equipment on the table at the back of the Bay:
Move equipment to a table with outlets (I couldn’t find any nearby outlets on that table).
make sure not to drop anything lol expensive stuff
Use the banana plug to banana plug wires to connect the +S and -S terminals on the battery holder to the digital multimeter HI input and LO respectively.
Use the banana plug to alligator clips to connect the +F and -F terminals on the battery holder to the INPUT + and - on the E-load respectively.
Turn on Katharine’s laptop, plug in the two USB cables from the e-load and multimeter (and plug it in to charge it)
Password is midsun
Plug in the power cables of the equipment and turn them on if you haven’t already
Open the MS Battery Testing folder, right-click inside of it, and click “Open in Terminal”
Type in the following to run Micah’s testing script:
Code Block python battery_test.py
Click OK (1 battery channel)
Click on File->Import Equipment Assignment
Select equipment_assignment (located in Documents → Single Cell Testing Data → Full Settings (i think lol, I might need to do some digging around but it's around there))
Click Import Test
Select rest_ir_test
Pick up a cell from the packaging (or just bring the whole box over)
The cells are in two boxes at the bottom of the shelves
Number the box that it came in, and the cell itself with Sharpie
Place in the Gamry cell holder with a Keysight 34410a
Click Edit Cell Name
Type in whatever number the cell you’re testing is, and OK
Start the test (screen should look something like this when it’s set up
Let the test run, it will do a 1-second rest, a 5-second low current (0.1C) discharge, and a 5-second higher current (0.4C) discharge, for a total of 11 seconds per cell. It should look something like this.
Wait until the Current Status is Idle, then repeat steps 13-19 for each cell. MAKE SURE TO EDIT THE CELL NAME BEFORE EACH TEST
NOTES:
Make sure you test every cell that you number with a sharpie, and don’t test any cells that you haven't marked with a number first
You don’t need to do the steps in the exact same order, you can start numbering the next cell with a sharpie during the 11s that the last cell is being tested or whatever works fastest or best for u
If you forgot to change the cell name, try to manually make a new folder for it using the same format, and cut+paste the data and log files to the new folder (Sort the files by “Date modified”, and cut and paste the 2 NEWEST data files, and the 2 NEWEST log files from the logs folder)
There’s a chance the E-load will start reading wrong or 0 values for the voltage. There’s a high chance that the hex bolt on the positive end of the cell holder is loose, just grab some pliers and tighten it (remove the cell before doing this):
The script will automatically save IR & OCV and IR data for each cell to the Single Cell Testing Data folder.
At the end of the testing session, ZIP the single-cell testing data folder and send it to the Slack channel.
Put everything back to where it was before!
I will make a small script that uses Micah’s GraphIV python script to analyze the data once it’s all collected or use https://github.com/kostubhagarwal/cell_qc_analysis.git
Thanks!!!!!
Production (Capacity) [DRAFT]
Place cells into [parallel cell charger(s)]
Charge cells at 1.45A (well below the standard charge spec [5])
Observe the thermal performance of batteries via thermistors/heat gun [optional]
Once fully charged, allow the cells to rest for 10 mins (recommended per spec sheet [5])
Commence discharge on [parallel cell charger(s)] at 1.70A
Once fully discharged, record values in the following MSXV_celltracking
Allow the cells to rest for 20 mins
Charge cells at 1A (well below the standard charge spec [5])
Observe the thermal performance of batteries via thermistors/heat gun
Once fully charged, allow the cells to rest for 4+ hours for the temperature to normalize temperature
Place all batteries in a box until module/pack assembly - when placing them in your module, check ocv and make sure it hasn’t dropped too much (self-discharge check), if discrepancies: record in MSXV_celltracking
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