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Interpretation Response #12-0040 ([Matthews Associates, Inc.] [Mr. George F. Foucher])

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

Interpretation Response Details

Response Publish Date:

Company Name: Matthews Associates, Inc.

Individual Name: Mr. George F. Foucher

Location State: FL Country: US

View the Interpretation Document

Response text:

June 4, 2012

 

 

Mr. George F. Foucher
Vice President Quality Assurance
Matthews Associates, Inc.
220 Power Court
Sanford, FL 32771

Ref. No. 12-0040
Dear Mr. Foucher:

This responds to your January 27, 2012 email and subsequent telephone conversation with a member of my staff requesting clarification of the requirements in the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to design type testing requirements for a lithium ion battery. The requirements you address are contained in Section 38.3 of the 5th Revised Edition of the United Nations (UN) Manual of Test and Criteria and are implemented through the provisions of § 173.185 of the HMR.

As provided by 38.3.2.1 of the UN Manual of Tests and Criteria, in the event that a cell or battery design type does not meet one or more of the test requirements, steps shall be taken to correct the deficiency or deficiencies that caused the failure before such cell or battery type is retested. In your letter you present three scenarios and pose several questions in response to these scenarios.

Scenario 1: A battery design does not meet the T3 test requirement because the open circuit voltage of the test battery was less than 90% of its voltage immediately prior to this procedure. Corrections must be incorporated into each of the batteries.

Q1. Can the same batteries that initially failed the T3 test be reused for the design type tests if the deficiency that caused the failure is corrected?

A1. In this scenario, the entire battery design must be evaluated to determine the cause of the failure. In general, we recommend against reusing batteries that do not pass the design type tests. The decision on whether to repair and reuse test cells or test batteries in this case depends on the how and why the cell or battery design failed to pass the test.

Q2. If the original batteries may be used for subsequent testing, can we begin at test T3 without repeating tests T1 and T2?

A2. No. The defect described in Scenario 1 is present in each of the batteries. Since correcting the defect would materially affect the test results, this change would constitute a new design type. The new battery design type must be subjected to each of the required tests beginning with test T1.

Scenario 2: A single battery does not meet the T2 test requirement. An analysis reveals that the failure is due to a workmanship issue and not a design flaw.

Q3. Is it acceptable to repair or replace only the single failed battery, subject that battery to tests T1 and T2 and then continue testing all the batteries from test T3?

A3. Provided you can ensure that the cause of the failure was the result of a workmanship issue associated with a single battery and not a deficiency in the battery design you may replace the failed battery and subject it to the tests you outline above. Since a failure of the T2 test may result in damage to the test battery, the decision on whether to repair a single test cell or battery depends on the nature and extent of the damage and must not impact the test results.

Scenario 3: Between the T3 test and the T4 test, one of the batteries is damaged during handling. The battery meets all of the design type tests to this point, but cannot be submitted to the Test T4.

Q4. Is it acceptable to repair or replace only the single failed battery, submit that battery to tests T1 through T3 and continue testing all the batteries from test T4?

A4. Since the damage to this battery is not a result of a design defect you may repair or replace the failed battery and subject it to the tests you outline above. The decision on whether to repair or replace a single test cell or battery damaged during handling depends on the nature and extent of the damage and must not impact the test results.

I hope this information is helpful. If you have further questions, please contact this office.

Sincerely,

 

Ben Supko
Senior Regulations Officer
Standards and Rulemaking Division

173.185

Regulation Sections

Section Subject
173.185 Lithium cells and batteries