SOW.pdf

SOW for Automated Screening of 18650 Cells

8 Aug 2023

1.0 Objective – To perform the screening of 18650 cells to identify outlying or discrepant cells from passing cells in an automated process.

2.0 Scope – Contractor will be provided with up to 10,000 cells in their as-received state from the manufacturer. The contractor shall Identify cells, read their data matrix code, measure Open Circuit Voltage, Sleeve Removal, Visual Inspection, Mass, Dimensional, and Capacity Cycling with DC Resistance. Also in scope is a compilation of the uniformity statistics along with segregation of passing cells from rejected cells.

3.0 NASA Inputs – This shall be performed on INR18650-M36 Li-ion cells from LG Chem provided by NASA. NASA will provide cell manufacturer datasheet. NASA will also provide data from its initial lot assessment {ILA} with dimensional measurements for creating Go No-Go gauges, which can be used to set electronic dimensional inspection stations. NASA will be responsible for all cell shipments to and from the contractor.

4.0 Contractor Tasks

4.1 Plan - The contractor shall submit test plan outline with their proposal specifying the order of the tests and a compliance matrix against the precision & accuracy requirements (sec 4.0 of EP-WI-037B). Proposed deviations from this SOW and EP-WI-037B must be defended with rationale for why it will provide results as good or better than if fully compliant with the specifications herein.

4.2 Screening - The contractor shall perform the cell screening per EP-WI-037B with Section 3.4 Self-Discharge Rate omitted. Furthermore, 3.5, Closed circuit voltage, CCV and 3.11 AC Impedance can be replaced with capacity cycling 3.12 done with DCR pulse and calculations.

Only test equipment having current calibrations traceable to NIST shall be utilized for reported measurements. Tests 3.2-3.3 shall be performed at the “as-received” state of charge.

4.3 Cycling – The cycling sequence shall be as follows

4.3.1 Discharge to 0% SoC

4.3.2 Charge to 100% SoC

4.3.3 Discharge to 10% SoC with a DCIR pulse at 50% SoC.

5.0 Reporting – An electronic report of the initial data and with statistics per EP-WI-037B section 3.13 is required within 5 weeks after receipt of the 10,000 cells and contractual authorization to proceed.

The spreadsheet shall also include unique conditions used for each test and calculate the uniformity statistics for each parameter along with plots of the data with the ± 3 sigma thresholds. Data report shall include the following parameters;

5.1 Manufacturer Serial Number

5.2 Contractor Serial Number

5.3 Charge Capacity

5.4 End of Discharge Voltage

5.5 Mass

5.6 Maximum and Minimum Height

5.7 Maximum and Minimum Diameter

5.8 DC Internal Resistance

5.9 Contractor Box Number

6.0 Hardware Disposition – The contractor shall return all cells at 10% SOC in vacuum sealed boxes.

Then provide them to a hazardous materials shipper after NASA approval of the data provided in

5.0. Failing cells shall be segregated from the passing cells in the return shipment. This shall be due within 5 weeks after receipt of the cells and contractually authorization to proceed. Deliveries shall be FOB origin.

7.0 Period of Performance – The period of performance of this contract shall be 1 year to allow NASA flexibility for cell deliveries and invoices for completed milestones shall be allowed.