The Energy Storage Devices (ESD) working group assesses the risk of uncontrolled fire involving batteries packed with or contained in equipment and identifies existing proactive and reactive safety measures. The assessment considers:

• The perspectives of States, air operators, and stakeholders from the entire supply chain to ensure a global view.
   
• Existing barriers to understand risk in the system in the context of expected continued growth in shipments (depending on quality of information available).
   
• Appropriate mitigation measures that can be applied globally to support the safe carriage of lithium batteries.
   

The ESD work plan includes additional information about the working group progress and upcoming targets.

The ESD working group developed a Bow-Tie diagram to visualize the hazard, the risk, the resulting consequences, and the reactive and proactive controls/measures designed to prevent unwanted outcomes.

Problem identification and project scoping » November 2021 – June 2022

• November 2021: ICAO DGP/28 considers various proposals to amend the ICAO Technical Instructions concerning the provisions for the safe transport of lithium batteries packed with or contained in equipment. DGP/28 agrees to task the Energy Storage Devices (ESD) working group to complete a risk assessment under the guidance of ICAO safety management experts.
   
• Energy Storage Devices working group drafts a work plan for analysis. The work plan includes a staged approach:
   
  • Step 1 – Create bowtie diagram
     
  • Step 2 – Complete risk assessment with and narrative report
     

Bowtie Development » July 2022 – February 2023

• Developed left side of the draft bowtie diagram to identify the protective barriers provided by the provisions specified within the ICAO Technical Instructions intended to prevent the top event (thermal runaway).
   
• November 2022: ICAO Working Group 22 (ICAO DGP-WG/22) reviewed potential data sources assist in development of the assessment including the Thermal Runaway Incident Report Program (TRIP) data, United States import/export commodity flow data, and assessment of transport airplane cargo compartment fire suppression capabilities consequence data.
   
• December 2022 – January 2023: Draft bowtie refined based on comments received from DGP-WG/22. Right side of draft bowtie diagram populated to identify recovery barriers available to mitigate consequences if a thermal runaway occurs.
   
• February 2023: ESD working group reviewed latest draft bowtie diagram, discussed ICAO suggested analysis methodology, taxonomy of scoring, and presentation template. Final comments incorporated into the draft bowtie diagram and task group formed to begin discussion of assessment.
   

Risk Assessment » March 2023 – August 2023

• Task group on assessment agreed to utilize System Theoretic Process Analysis (STPA) techniques facilitated by ICAO safety management experts. The STPA is a modern risk assessment methodology recommended by ICAO to overcome limitations of conventional assessment methods that utulize probability and consequence.
   
• Assess barrier effectiveness and criticality using STPA methodology and taxonomy, including identification of hazards, safety constraints, control structure, causal scenarios (CS) and unsafe control actions (UCA).
   
• May 2023: ESD working group meeting followed by DGP-WG/23. Consider preliminary analysis and preparations for DGP/29 in November 2023. Review schedule, desired outcomes and potential recommendations.
   
  • Refine analysis and develop accomanying narrative report
     
  • Submit analysis for consideration by DGP/29 (Novmeber 2023)
     

PHMSA's International Program maintains an open dialog with U.S. stakeholders and regularly updates the Lithium Battery Air Safety Advisory Committee (The Committee) on activities of the Energy Storage Devices (ESD) working group.

September 2021 Lithium battery Air Safety Advisory Commmittee

• Public meeting of the Committee. PHMSA informed the Committee of official proposals submitted to the International Civil Aviation Organization (ICAO) Dangerous Goods Panel (DGP) relevant to lithium battery safety and collected comments.
   
• The Committee recalled its role to facilitate communication between those in the air transport supply chain and the federal government regarding the safe air transportation of lithium cells and batteries and economic and social impacts of the regulation of such transportation.
   

November 2021 ICAO DGP/28

• PHMSA public meeting in preparation for ICAO DGP/28 to gather U.S. stakeholder inputs on official proposals to amend the ICAO Technical Instructions provisions for lithium batteries including when packed with or contained in equipment.
   
• ICAO DGP considered amendments to the Technical Instructions applicable to lithium batteries including when packed with or contained in equipment.
   

May 2022 Lithium Battery Air Safety Advisory Commmittee

• PHMSA briefed the Committee on the ICAO DGP Energy Storage Devices (ESD) working group efforts to conduct a risk assessment for lithium batteries packed with or contained in equipment. The Committee agreed to gather, coordinate, and provide U.S. stakeholder input to PHMSA and FAA to support the risk assessment initiative.
   
• The Committee discussed that updates on the assessment initiative would be made publicly available to ensure transparency and equitable opportunities for U.S. stakeholders to participate in the data sharing and inform PHMSA and FAA considerations within the ESD working group. Committee members were encouraged to identify potential data sources to contribute to development of the risk assessment.
   

October 2022 Lithium Battery Air Safety Advisory Committee

• PHMSA presented the left side of the draft bowtie diagram identifying the protective barriers specified within the ICAO Technical Instructions intended to prevent the top event (thermal runaway).
   
• Presentations from Commmttee members Underwriters Laboratories (UL) on the Thermal Runaway Incident Program (TRIP) and PRBA the Rechargeable Battery Association on import/export data were discussed in the context of how this data could inform the assessment. Both were invited to present to the ICAO DGP Working Group 22 meeting.
   

November 2022 ICAO Dangerous Goods Panel Working Group 22 meeting

• PHMSA public meeting in preparation for ICAO DGP Working Group 22 to gather U.S. stakeholder inputs on official proposals to amend the ICAO Technical Instructions and provide updates on activities of the ESD working group.
   
• ICAO DGP reviewed presentations from UL and PRBA covering potential data sources that could inform development of the risk assessment.
   

December 2022 to May 2023 Lithium Battery Air Safety Advisory Commitee

• The Committee agreed to review and provide comments to the draft bowtie diagram. Consideration assigned to the Regulations and Gap Analysis Sub-Committee with support from the Data Collection and Analysis Sub-Committee.
   
• The Committee was provided the completed draft bowtie diagram in March 2023.
   
• The Committee encouraged to provide U.S. stakeholder inputs on the relevant data appropriate for consideration of the protective barriers identified within the bowtie diagram and how the data might be incorporated into the risk assessment.
   
• Consideration of the bowtie diagram and risk assessment initiative on the agenda for the anticipated Spring Committee public meeting.