daily · Clean Energy

EPRI finds lower historical battery failure rates, with limits on risk predictions

EPRI reports a 98% fall in recorded failures per deployed GWh from 2018 to 2025. The historical database does not predict a specific project's risk or show that battery fires have been eliminated.

By Greener Numbers Editorial Team · Published October 26, 2026 · Updated 10/26/2026

Electric Power Research Institute analysis finds that the recorded global failure rate for lithium-ion battery energy storage systems, measured per deployed gigawatt-hour, fell 98% from 2018 to 2025. Utility Dive reported the findings on October 13. This is a historical rate relative to a growing installed fleet, not a claim that total failure risk has disappeared.

The report distinguishes calendar-year failures per deployed energy capacity from failures per container and operational experience. Its sensitivity analysis estimates an annual operational range of 0.04% to 0.14%. These measures have different denominators and should not be treated as interchangeable odds for a particular proposed installation.

EPRI says the dataset covers roughly seven years of operation, with only a small fraction of units beyond six years. It explicitly discourages using the aggregate result to predict failure likelihood at an individual project. Design, codes, chemistry, site configuration and aging can change the relevant risk.

The report compares battery results with transformer studies but warns that transformers have much longer operating histories. A similar historical percentage does not establish identical failure consequences, lifetime behavior or emergency-response needs for the two technologies.

Utility Dive reports that older systems and indoor facilities need particular attention, and that safety reviews, barriers and some retrofits can reduce risk. Risk reduction is not risk elimination. A community considering a battery project still needs site-specific engineering, code review and emergency planning.

The findings provide context for storage permitting and operations, not proof that every battery project should be approved or that every nearby household is safe under all conditions. The report supports continued safety work and careful treatment of older systems rather than a blanket assurance about all future installations.

Official source: restservice.epri.com ↗