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Interpretation Response #17-0101

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

Interpretation Response Details

Response Publish Date:

Company Name: Preco, Inc.

Individual Name: Brian Wiedow

Location State: WI Country: US

View the Interpretation Document

Response text:

July 23, 2018

Brian Wiedow
Regulatory Specialist
Preco, Inc.
500 Laser Drive
Somerset, WI 54025

Reference No. 17-0101

Dear Mr. Wiedow:

This letter is in response to your September 1, 2017, email and subsequent phone and email conversations requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to the testing of lithium ion batteries in accordance with Part III, Sub-section 38.3 of the United Nations (UN) Manual of Tests and Criteria. In your email and subsequent phone and email conversations, you describe the following scenario:

  • Your company receives lithium ion cells from a supplier. These cells are of a type that has passed applicable UN 38.3 tests.
  • Your company uses the lithium ion cells to build an assembly. The lithium ion cells installed, in either series or parallel, are electrically connected. This configuration has not been UN 38.3 tested.
  • The assembly is placed in a container and then shipped to the customer, where they install control boards and terminals in the assembly to complete the lithium ion battery. This completed battery has passed UN 38.3 testing.

Specifically, you ask if the assembled cells must undergo UN 38.3 testing before being shipped to the customer.

The answer is yes. In accordance with Part III, Sub-section 38.3 of the UN Manual of Tests and Criteria, a battery is defined as "two or more cells which are electrically connected together and fitted with devices necessary for use, for example, case, terminals, marking and protective devices." Based on the information provided in your email, it is the opinion of this Office that because the cell assembly shipped to the customer is electrically connected and contains some components of a battery, it meets the general definition of a battery, even though the customer fits the assembly with additional devices at a later stage to complete the battery.

This partial battery must pass the appropriate tests, unless meeting an exception from UN 38.3 testing in § 173.185, such as § 173.185(e) for low production runs and prototype batteries. If it cannot pass the appropriate tests or meet an exception, you may wish to apply for a special permit in accordance with Part 107, Subpart B. Please note that the shipment to the customer must also comply with all applicable packaging requirements for lithium ion batteries.

I hope this information is helpful. Please contact us if we can be of further assistance.


Dirk Der Kinderen
Chief, Standards Development
Standards and Rulemaking Division

173.185, 173.185(e)

Regulation Sections

Section Subject
173.185 Lithium cells and batteries