Invinity Energy Systems — Hazardous Materials Safety Interpretation

Page 11200 New Jersey Avenue, SE Washington, DC 20590 U.S. Department of Transportation Pipeline and Hazardous Materials Safety Administration June 10, 2025 Derek Polman-Tuin Director Invinity Energy Systems 1250 E. Pender Street Vancouver, B.C., Canada V6A 1W8 Reference No. 25-0058 Dear Mr. Polman-Tuin: This letter is in response to your April 23, 2025 letter requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to wet batteries transported via highway. Specifically, you explain that your company designs and manufactures vanadium flow batteries classified as “UN2794, Batteries, wet, filled with acid, electric storage, 8.” You state that these batteries contain a non-flammable, aqueous electrolyte solution containing vanadium sulfate. You are seeking confirmation that the transportation of these batteries, as described below and in accordance with the requirements of § 173.159(e), is not subject to any other requirement of the HMR. • The battery is shipped fully discharged. • The power and energy storage elements (i.e., the tanks) of the battery are physically separated and the power elements (i.e., stacks) contain no stored energy. • No voltage on the terminals (0 V). • Stacks have no exposed terminals to prevent short circuiting. • Stacks are firmly secured within a rigid metal racking system that separates each stack to prevent short circuiting. • The metal racking system containing the stacks is firmly secured and integrated into a 20-ft International Organization for Standardization/Convention of Safe Containers (ISO/CSC) certified steel container. • The 20-ft ISO/CSC certified container has re-enforced structures, fixtures, and secondary containment. • No other hazardous material is shipped with the complete unit. • No other materials are transported on the vehicle.#

Page 2Based on the information as described and the photographs you provided, it is the opinion of this Office that the batteries meet the requirements of § 173.159(e) for highway transport. Please note that batteries transported in this manner are still subject to incident reporting requirements in § 171.15. I hope this information is helpful. Please contact us if we can be of further assistance. Sincerely, Dirk Der Kinderen Chief, Standards Development Branch Standards and Rulemaking Division#

Page 3Baker, Y. 25-0058 From: INFOCNTR (PHMSA) To: Dodd, Alice (PHMSA) Cc: Hazmat Interps; Baker, Yul (PHMSA) Subject: FW: Request for a letter of interpretation Date: Wednesday, April 30, 2025 9:29:55 Attachments: image001.png Letter of Interpretation_DOT.docx Hi Alice, Please see the attached interpretation request. Let us know if you need anything. Sincerely, Janaye From: Derek Polman-Tuin <DPolmanTuin@invinity.com> Sent: Tuesday, April 29, 2025 6:58 PM To: INFOCNTR (PHMSA) <INFOCNTR.INFOCNTR@dot.gov> Cc: Benjamin Duperthal <bduperthal@invinity.com>; Derek Polman-Tuin <DPolmanTuin@invinity.com> Subject: Request for a letter of interpretation You don't often get email from dpolmantuin@invinity.com. Learn why this is important CAUTION: This email originated from outside of the Department of Transportation (DOT). Do not click on links or open attachments unless you recognize the sender and know the content is safe. Good morning, Please see attached request for a letter of interpretation. The letter outlines our understanding of the regulations, our battery classification and detailed information (with pictures), which confirms it meets the highway(Road) requirements under 49CFR 173.159(e). Mailing Address: Invinity Energy Systems Attn: Derek Polman-Tuin 1250 E. Pender Street Vancouver, BC Canada V6A 1W8 Please feel free to reach out to me if you have any questions. Thank you, Derek#

Page 4Derek Polman-Tuin Director, Global Logistics & Trade Compliance dpolmantuin@invinity.com VAN:+1.604.335.7117#