Safety

Root Cause Of BESS Failures Publicly accessible records of BESS thermal events categorized by root-cause failure mode(s) can be limited and/or incomplete. While specific enumeration of root-cause failure modes of BESS thermal events is limited and can be highly nuanced, they can be broadly grouped in the following categories:

ROOT CAUSE CATEGORIES

THERMAL EVENT DATABASES

UL- 171 thermal events

EPRI26 with root-cause REASONS FOR LIMITED DATABASES WITH ROOT CAUSES 1. Difficulty assessing damaged components 2. Significant cost and time needed to investigate, 3. hesitancy to provide root-case for specific event due to litigation concerns

Examples of root-cause risks by category

Note: Event root causes can expand across different categories and/or information to assess certain root-causes may not be available.

For most common BESS fire root-causes see BESS section

Extracted from the PDF; charts and images may read imperfectly.