Japans response to Action item 2 EVSGTR IWG17

Japan’s response to Action item 2 EVS-GTR IWG#17

Key messages n “(A) Is thermal propagation due to an internal short single cell thermal runaway a problem in the field? ” and “(B) Simulation of a single cell thermal runaway” are important in order to continue research. Action Items 2 All members identify specific questions in the white paper to contracting parties for agreement in order to continue with research. Responsibility Due ALL　China, EC, 12/01/18 Japan, US, Canada, Korea, OICA n Simulate “Internal short circuit caused by cell manufacturing failure” in this test. n If there is another cause which may lead to thermal runaway and thermal propagation, clarify this and set new test to prevent this from resulting in thermal runaway, not initiate forcible thermal runaway in thermal propagation test to cover this. n Need to investigate the methods which can simulate “Internal short circuit caused by cell manufacturing failure”. EVS-GTR IWG#17 JAPAN

Action item 2 in IWG#16 n (A) and (B) are preconditions of this test. Need to decide these first. Questions (A) Is thermal propagation due to an internal short Note (D) Ignition of vented gases and other risks Preconditions of this test. Necessary to decide first. Forcible thermal runaway or internal short circuit? Depends on test methods and conditions. These will be decided based on (B). No conflict (E) Evaluation Criteria Important but no conflict (F) Repeatability and Reproducibility Depends on test methods and conditions. These will be decided based on (B). single cell thermal runaway a problem in the field? (B) Simulation of a single cell thermal runaway (C) Elimination of Detection and Intervention Technologies (G) Manipulation of test-device (H) Specifics of initiation methods and environmental (I) conditions Re-testing and re-homologation (J) Documentation requirements Same as other tests No conflict EVS-GTR IWG#17 JAPAN

Responses from CPs and OICA EU/JRC (A) (B) (C) (D) (E) (F) (G) (H) Is thermal propagation due to an internal short single cell thermal runaway a problem in the field? Simulation of a single cell Select thermal runaway ed Elimination of Detection and Intervention Technologies Ignition of vented gases and other risks Evaluation Criteria OICA Select ed KOREA Select ed JAPAN CHINA Select ed CANADA US Select ed Repeatability and Reproducibility Manipulation of test-device Specifics of initiation methods and environmental conditions (I) Re-testing and rehomologation (J) Documentation requirements EVS-GTR IWG#17 JAPAN

Causes which may lead to thermal runaway n Various causes may lead to thermal runaway. n GTR 20 covers these causes except for internal short circuit caused by manufacture failure. Example of FTA resulting in “Thermal runaway” and “Thermal propagation” Thermal propagation Thermal runaway Overcharge Over-discharge Heat External heat Self Heating Fire Over temperature Over current : Covered by requirements in GTR 20* : Not covered by requirements in GTR 20* Short circuit (External) Short circuit (Internal) *Except for current thermal propagation requirement Low temperature Shock +/electrodes/ foils contact Covered by thermal propagation test Crush Manufacture failure EVS-GTR IWG#17 JAPAN

Causes which may lead to thermal runaway n Manufacturing failures will not be completely eliminated in theory. TF 5 meeting 5/2015 *not uploaded EVS-GTR IWG#17 JAPAN

Causes which may lead to thermal runaway n Causes are also prevented by system (e. g. BMS, fuse, etc. ) n But internal short circuit is not preventable. (OICA reported that detection may be possible, but prevention is difficult. ) EVS-06 -23 e EVS-GTR IWG#17 JAPAN

Causes which may lead to thermal runaway n If there is another cause which may lead to thermal runaway, clarify this and set new test to prevent this from resulting in thermal runaway, not initiate forcible thermal runaway in thermal propagation test to cover this. Example of FTA resulting in “Thermal runaway” and “Thermal propagation” Thermal propagation Thermal runaway Overcharge Over-discharge Heat External heat Self Heating ? ? Should be covered by new test : Covered by requirements in GTR 20* : Not covered by requirements in GTR 20* *Except for current thermal propagation requirement Fire Over temperature Over current Short circuit (External) Short circuit (Internal) Low temperature Shock +/electrodes/ foils contact Covered by thermal propagation test Crush Manufacture failure EVS-GTR IWG#17 JAPAN

Initiation method research Nail • It’s hard to control penetration layers. Challenges Heater • There are some samples which are hard to induce internal short. • Need manipulation to insert nail. • Need manipulation to set heater. Laser ・・ Now researching ・・ EVS-GTR IWG#17 JAPAN

Summary n “(A) Is thermal propagation due to an internal short single cell thermal runaway a problem in the field? ” and “(B) Simulation of a single cell thermal runaway” are important in order to continue research. n Simulate “Internal short circuit caused by cell manufacturing failure” in this test. n If there is another cause which may lead to thermal runaway and thermal propagation, clarify this and set new test to prevent this from resulting in thermal runaway, not initiate forcible thermal runaway in thermal propagation test to cover this. n Need to investigate the method which can simulate “Internal short circuit caused by cell manufacturing failure”. EVS-GTR IWG#17 JAPAN

Future Plan n Need to investigate the method which can simulate “Internal short circuit caused by cell manufacturing failure”. n Assess new initiation methods whether it can simulate this scene. 2017 #14 #15 2018 #16 2019 2020 #17 IWG Report Repeatability and reproducibility test (Nail) Japan Research Repeatability test (Heater) Field data investigation Possible initiation method test research (e. g. Laser) EVS-GTR IWG#17 JAPAN

Thank you for your attention

APPENDIX

Difference of phenomena in thermal runaway n Depending on initiation methods, the phenomena in thermal runaway are different. n Need to clear the cause of thermal runaway and set initiation method which can simulate this. EVS 1416 -603 EVS-GTR IWG#17 JAPAN

Q&A Slide No. Questions Answers EVS-GTR IWG#17 JAPAN