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Interpretation Response #07-0106 ([Cobasys] [Mr. Anthony J. Serventi])

Below is the interpretation response detail and a list of regulations sections applicable to this response.

Interpretation Response Details

Response Publish Date:

Company Name: Cobasys

Individual Name: Mr. Anthony J. Serventi

Location State: MI Country: US

View the Interpretation Document

Response text:

Jul 27, 2007

Mr. Anthony J. Serventi                 Reference No. 07-0106

Senior Counsel


3740 Lapeer Road South

Orion, MI 48359

Dear Mr. Serventi:

This is in response to your letter dated May 23, 2007 requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to design- type testing of lithium-ion cells and batteries. The specific requirements you address are contained in section 383 of the United Nations Manual of Tests and Criteria and are implemented through the provisions of § 173.185 of the HMR.

In your letter you describe a hybrid electric vehicle battery system consisting of 192-3.3 volt A123 cylindrical lithium-ion cells utilizing approximately 518 grams of aggregate equivalent lithium content. The battery system is equipped with a system that monitors cell voltage and temperature and incorporates a service disconnect feature. Each cell passed the design-type tests in section 38.3 of the UN Manual of Tests and Criteria and the cells in this assembly are electrically connected by a circuit board. It is your opinion that since the individual cells passed the applicable tests and incorporate additional safety systems, the cell assembly constitutes a "battery assembly" as described in 38.3.3 of the UN Manual of Tests and Criteria and thus the assembly is not required to be tested in accordance with the design-type tests outlined in section 38.3.

We do not agree. The system you described meets the definition of a battery or a battery pack, defined in section 38.3 of the UN Manual of Tests and Criteria as one or more cells electrically connected together by permanent means, including case, terminals and markings. Except for single cell batteries, each new lithium cell and battery design-type is subject to the tests in the UN Manual of Tests and Criteria, even if the cells that make up the battery have been tested. The fact that the cells are electrically connected by a circuit board that can be disconnected does not mean this assembly of cells constitutes a battery assembly.

If you believe your hybrid electric vehicle battery system provides and equivalent level of safety to the HMR requirements without additional testing, you may wish to apply for a special permit through the Office of Hazardous Materials Special Permits and Approvals at 202-366-4535.

I hope this information is helpful.


John A. Gale

Chief, Standards Development

Office of Hazardous Materials Standards


Regulation Sections

Section Subject
173.185 Lithium cells and batteries