Ses Ai Corporation · NYSE:SES
Ses Ai — SES Holdings — SPAC Merger (July 2021)
25 slides from Ses Ai's SPAC merger presentation, Jul 13, 2021
Slide 1: Summary of 3rd party testing of SES hybrid lithium-metal cells
1 Summary of 3rd party testing of SES hybrid lithium-metal cells Compiled by Dr. Billy Wu and Mark Newman for Ivanhoe Capital Acquisition Corp. Executive summary SES is a manufacturer of next generation hybrid lithium-metal batteries with demonstrated multi-layer and multi-Ah cells. In this report,
Slide 2: Contents
2 Contents Executive summary ................................................................................................................. 1 1. Introduction ....................................................................................................................... 3 2. Highlights of
Slide 3: Introduction and Highlights of electrical testing results
3 1. Introduction SES is a developer of hybrid lithium-metal batteries with the potential to achieve an energy density >400 Wh/kg and 1,000 Wh/L which would represent best-in-class performance. The aim of this document is to summarise the 3rd party testing results performed on SES’s cells which was
Slide 4: Highlights of safety tests
4 Figure 3: Energy density and energy retention (relative to 0.1C at 25 ˚C) of the SES cells at different temperatures and C-rates. Tested at Exponent (solid lines) and Eclipse Energy (dotted lines). 3. Highlights of safety tests In order to validate the safety performance of SES’s hybrid lithium-me
Slide 5: Author profiles
5 Author profiles Dr. Billy Wu Dr. Billy Wu is a senior lecturer (associate professor) in electrochemical engineering at Imperial College London, UK. He co-leads the Electrochemical Science and Engineering group which works at the interface between fundamental science and engineering application of
Slide 6: Appendix – Exponent testing data
6 Appendix 1 – Exponent testing data Figure 4: Energy density and energy retention (relative to 0.1C at 25 ˚C) of the SES cells at different temperatures and C-rates. Tested at Exponent. Figure 5: Fast charging data for the SES cells at 25 ̊C from 10%-80% state-of-charge at 4C taking 10.5 mins. Test
Slide 7: Voltage and temperature profiles grouped by temperature
7 Figure 6: Voltage and temperature profiles for SES cells tested at 0˚C, 25 ˚C and 45 ˚C, grouped by temperature. Tested at Exponent.4 4 Note that the temperature plotted is at the top centre of the cell which is more representative of the intrinsic cell heat generation. Whilst it is acknowledged t
Slide 8: Voltage and temperature profiles grouped by C-rate
8 Figure 7: Voltage and temperature profiles for SES cells tested at 0˚C, 25 ˚C and 45 ˚C, grouped by C-rate. Tested at Exponent.
Slide 9: Appendix – Eclipse Energy testing data
9 Appendix 2 – Eclipse Energy testing data Figure 8: Energy density at different C-rates (left) and energy retention relative to 0.1 C energy at 25 ̊C from Eclipse Energy. Figure 9: Fast charging data for the SES cells at 25 ̊C from 10%-80% state-of-charge at 4C taking 10.5 mins. Tested at Eclipse E
Slide 10: Voltage profiles for SES cells grouped by temperature
10 Figure 10: Voltage profiles for SES cells tested at 0˚C, 25 ˚C and 45 ˚C, grouped by temperature. Tested at Eclipse Energy.
Slide 11: Appendix – Discharge testing procedure
11 Appendix 3 – Discharge testing procedure • Capacity check o Rest for 2 hrs in each different temperature chamber (0°C, 25°C, or 40°C) o Constant current charge at 0.1C (0.42 A) until voltage = 4.3 V o Constant voltage hold at 4.3V until current <0.05C (0.21 A) o Rest for 20 minutes o Constant cur
Slide 12: Discharge testing procedure (continued)
12 o Rest for 10 mins o Constant current discharge at 5C (21 A) until voltage = 2.5 V o Rest for 30 mins o Constant current discharge at 0.1 C (0.42 A) until voltage = 2.5 V o Rest 10 mins • Rate capacity test (7C) o Constant current charge 0.33C (1.4 A) until voltage = 4.3 V o Constant voltage hold
Slide 13: Appendix – Fast charging protocol
13 Appendix 4 – Fast charging protocol • Initial discharge o Constant current discharge at 0.1C (0.42 A) until voltage = 2.5 V for conditioning o Rest for 10 mins • Capacity check cycle o Constant current charge at 0.33C (1.4A0 until voltage = 4.3V o Constant voltage hold at 4.3V until current < 0.0
Slide 14: Appendix – External short circuit testing set-up and data
14 Appendix 5 – External short circuit testing set-up and data Test conditions • Circuit formed using 3/0- and 2/0-gauge cables and controlled with a 12VDC rlay • Current sensing was performed using a 0.25 mΩ calibrated shunt resistor • External resistance: ~4.8 mΩ o 1 kHz AC impedance measured usin
Slide 15: External short-circuit test data
15 Figure 12: External short-circuit test data with 3 repeats performed at Exponent.6 6 Note that an additional cell was tested and passed the external short-circuit test, however due to an error in the data logging this has not been shown for clarity of communication. The abrupt drop in short-circu
Slide 16: Appendix – Overcharge test set-up and results
16 Appendix 6 – Overcharge test set-up and results Test conditions • Charge at 1C (2.89 A) stopping at 8.5 V (2 x charge voltage) or after one hour (200% SOC) • Sample rate: 1 Hz (1 second/sample) • Temperature recorded: positive tab, negative tab, clamp centre, and ambient • Temperature and voltage
Slide 17: Overcharge tests with repeats
17 Figure 14: Overcharge tests with 3 repeats performed at Exponent.7 7 Note that in test number 3, the centre thermocouple lifted off from the cell three times during the test and was manually placed back on. This did not interfere with the maximum temperature measured at the end of charge. The tes
Slide 18: Appendix – Nail penetration test set-up and data
18 Appendix 7 – Nail penetration test set-up and data Test conditions • Nail controlled by hydraulic cylinder with 75 mm stroke length • Hight adjusted to penetrate cell by <5 mm • Sample rate: 10 Hz (100 ms/sample) • Temperatures recorded positive tab, negative tab, clamp center and ambient • The n
Slide 19: Nail penetration testing results
19 Figure 16: Nail penetration testing results with 3 repeats performed at Exponent.
Slide 20: Appendix – ARC test set-up and data
20 Appendix 8 – ARC test set-up and data • ARC testing was performed on 2 SES lithium-metal cells • Prior to ARC testing, each cell was charged with a constant current of 0.64 A to 4.25 V with a constant voltage hold to a 0.16 AA cut-off • The cell was clamped between two metal plates (Figure 17) wi
Slide 21: Cell with clamp installed in ARC chamber
21 Figure 18: Cell with clamp installed in ARC chamber.
Slide 22: ARC testing results performed at Exponent
22 Figure 19: ARC testing results performed at Exponent.8 • The onset temperature where self-heating rates exceed 0.04 °C/min occurred between 115-176 °C • Cell D20 exhibited a thermal runaway temperature of 324°C where thermal runaway is defined as a self-heating rate in excess of 15°C/min o This i
Slide 23: ARC test results for cell D20
23 Figure 20: ARC test results for cell D20 with full test data (top) and zoom in of the data (bottom) performed at Exponent.
Slide 24: ARC test results for cell D21
24 Figure 21: ARC test results for cell D21 with full test data (top) and zoom in of the data (bottom) performed at Exponent.9 9 Cell D21 did not experience thermal runaway due to testing protocol error, activating the cooling air at ~300 °C early (red arrow of bottom plot). Low inconsistent levels
Slide 25: References
25 References [1] Exponent, SES cell electrical tests, 2021. [2] Eclipse Energy, Test Report: RPT-21-635_Ivanhoe_Cell Characterization_Rev.1, 2021.