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Interpretation Response #09-0182 ([GE Sensing & Inspection Technologies] [Mr. Tom Piggin])

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

Interpretation Response Details

Response Publish Date:

Company Name: GE Sensing & Inspection Technologies

Individual Name: Mr. Tom Piggin

Country: UK

View the Interpretation Document

Response text:

October 13, 2009




Mr. Tom Piggin

Electronic Engineer

GE Sensing & Inspection Technologies

Fir Tree Lane





Ref. No. 09-0182

Dear Mr. Piggin:

This responds to your August 4, 2009 request for clarification of the requirements in the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to lithium battery packs. Specifically, you ask if the configurations described in your letter constitute a single lithium ion battery pack or separate lithium ion batteries.

In your letter you describe two battery packs, each of which consists of five lithium batteries in a single housing. Each of the lithium ion batteries contains two or more cells and will have an aggregate lithium content of 8.1 grams (99Wh).

In the first example, the five lithium batteries lead to a single connection, but remain electrically isolated while in transportation. Provided the batteries remain isolated during transportation, this configuration would constitute separate lithium ion batteries for purposes of the HMR, and may be transported in conformance with requirements in §172.102, Special Provision 189 by highway and §173.185 as a Class 9 by air and vessel.

In your second example, the batteries are electrically connected but utilize diodes to ensure that the battery pack will not activate during transportation. In this case, the five battery packs installed in the power supply described in your letter are electrically connected and must be described as a single lithium ion battery pack with an aggregate lithium content of

40.5 grams equivalent lithium content (500Wh) and transported as Class 9 material in conformance with the requirements of §173.185.

I hope this answers your inquiry. If you have further questions, please do not hesitate to contact this office.


Charles E. Betts

Chief, Standards Development

Office of Hazardous Materials Standards


Regulation Sections

Section Subject
173.185 Lithium cells and batteries