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Interpretation Response #15-0009 ([Mr. Mike Revis])

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

Interpretation Response Details

Response Publish Date:

Company Name:

Individual Name: Mr. Mike Revis

Location State: WA Country: US

View the Interpretation Document

Response text:

August 19, 2015

Mr. Mike Revis
742 Industry Drive
Building 16
Tukwila, WA 98188

Ref. No. 15-0009

Dear Mr. Revis:

This responds to your January 15, 2015 email requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180). Specifically, you ask for clarification on the size limits under the exception in § 173.185(c)(1)(i) for lithium ion batteries.

You state the lithium ion battery in question has a rating of 81.4 Watt-hour (Wh). The two cells that make up the battery each have a rating of 40.7 Wh. You have asked if this battery qualifies for the exceptions in § 173.185(c)(1)(i).

The answer is yes. Section 173.185(c)(1)(i) states that the Wh rating may not exceed 20 Wh for a lithium cell or 100 Wh for a lithium ion battery. The United Nations (UN) Manual of Tests and Criteria defines a battery as "one or more cells which are electrically connected together by permanent means." The 100 Wh size limit applies to your battery irrespective of whether the component cells exceed the 20 Wh rating for a cell. Therefore, the exceptions in § 173.185(c)(1)(i) apply to your lithium ion battery configuration since the battery does not exceed 100 Wh.

I hope this answers your inquiry. If you need additional assistance, please contact this Office at 202-366-8553.



Dirk Der Kinderen
Acting Chief, Standards Development Branch
Standards and Rulemaking Division


Regulation Sections

Section Subject
173.185 Lithium cells and batteries