IEC 62485-5 specifies safety requirements for the installation and operation of stationary lithium-ion secondary battery systems, published by the International Electrotechnical Commission (IEC). It is Part 5 of the IEC 62485 series and addresses the specific hazards of lithium-ion batteries in stationary applications — particularly thermal runaway, fire, toxic gas emission, and electrical hazards — which differ significantly from the lead-acid battery hazards covered by IEC 62485-2.
Published by: International Electrotechnical Commission (IEC)
Current edition: IEC 62485-5:2020
Adopted as: EN IEC 62485-5:2021 (Europe)
Companion standards: IEC 62485-2 (lead-acid stationary), IEC 62619 (industrial Li safety), IEC 63056 (EESS safety), NFPA 855 (US installation standard)
Scope
IEC 62485-5 applies to stationary lithium-ion battery installations with a maximum aggregate DC voltage of 1,500 V. It covers batteries installed in industrial facilities, commercial buildings, and residential applications, and addresses safety during installation, normal operation, fault conditions, maintenance, and disposal. The standard covers both indoor and outdoor installations and addresses the full range of stationary application types from small UPS systems to large grid-scale BESS.
Key Requirements
The standard specifies requirements for siting and separation distances to minimise fire spread risk from a thermal runaway event, ventilation to manage toxic and flammable gas release during thermal runaway, fire detection and suppression system interfaces, BMS requirements for monitoring and protective shutdown, electrical protection including isolation, fusing, and arc fault protection, and requirements for safe access, maintenance procedures, and emergency response information.
Unlike lead-acid batteries where hydrogen gas management is the primary installation concern, lithium-ion installations must address the more complex hazard of thermal runaway propagation, which can release a mixture of toxic gases (HF, CO, VOCs) and create fire conditions that are difficult to extinguish with conventional means. IEC 62485-5 requirements for ventilation and fire suppression reflect this more complex hazard profile.
Relevance to Battery Engineering
IEC 62485-5 is the key installation safety reference for stationary lithium-ion BESS in European markets. For battery system engineers, compliance with IEC 62485-5 drives design decisions about BMS alarm and shutdown interface requirements, enclosure ventilation design, thermal management system fail-safe behaviour, and the documentation and labelling required for safe installation and emergency response. Understanding the standard’s requirements is essential for engineers designing battery systems that will be installed in buildings, data centres, or industrial sites subject to European safety regulations.
Disclaimer: This is not a definitive guide, just an indication and it is important that you always go back to the source for legislation.
See also: IEC 62485-3, IEC 62933-5-1