IEC 62619
IEC 62619 is the international product-safety standard for secondary (rechargeable) lithium cells, modules and battery systems in industrial applications, and stationary grid storage is one of its named application classes.
It defines the type tests — overcharge, external short circuit, thermal abuse (an oven hold commonly cited at 85 degrees C), forced internal short circuit, and, since the 2022 edition, a thermal-runaway propagation test — that prove a battery fails in a controlled way.
You meet it first on the certification line of a cell datasheet and again in every lender due-diligence checklist. It certifies the battery product only; the fire test (UL 9540A), the system listing (UL 9540) and installation rules (NFPA 855) sit in separate layers above it.
Reviewed July 2026 by Sergey Syrvachev
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What it is (precise)
The full title is "Secondary cells and batteries containing alkaline or other non-acid electrolytes — Safety requirements for secondary lithium cells and batteries, for use in industrial applications." It specifies design, type-test and quality requirements for lithium cells, modules and complete battery systems in industrial duty — stationary energy storage, UPS, telecom and off-road motive uses such as forklifts and rail.
Road electric vehicles are expressly excluded and fall under separate automotive standards. Edition 1 appeared in 2017; the second edition, IEC 62619:2022, is what current projects should reference. Certificates are typically issued through the IECEE CB scheme, so one test campaign is recognised across member countries rather than repeated per market.
In the equipment hierarchy — cell, module, rack, container — IEC 62619 sits at the bottom two or three levels, testing the battery product before it is built into a container. Beyond abuse tests it imposes functional requirements on the protection layer: the system must limit overcharge voltage, overcurrent and overheating, which in a grid-scale rack running at up to 1500 VDC is enforced by the BMS.
It pairs with IEC 62620 (performance and marking), is supplemented by IEC 63056 for electrical energy storage systems specifically, and is referenced from IEC 62933-5-2, the system-level safety standard for grid-integrated storage. Knowing which document owns which level is half the battle.
Why it matters in a real grid-scale project
For a utility-scale project the standard is both an engineering gate and a commercial one. Cell and module suppliers must show IEC 62619 type-test certificates before their product is accepted into a container design; owners, lenders and insurers list it as a minimum qualification line in technical due diligence and supply agreements.
Outside North America it is usually the primary battery-product certification demanded; in the US market UL 1973 plays the equivalent role for stationary packs and racks, and most major cell makers carry both to sell globally. A missing, expired or wrong-model certificate is not a paperwork nuisance — it can stall financing, insurance binding or permitting for weeks.
Crucially, IEC 62619 certifies the battery product, not the installed system. It does not tell an Authority Having Jurisdiction that a multi-megawatt-hour container is safe to site near homes or a substation.
Propagation behaviour at rack and unit scale is characterised by UL 9540A as a test method; the complete ESS is listed under UL 9540; installation rules — separation distances, suppression, the Hazard Mitigation Analysis — come from NFPA 855; and explosion control of flammable Off-gassing is handled by NFPA 68 (Deflagration venting) and NFPA 69 (prevention). IEC 62619 is one layer in that stack, never the whole compliance story, and treating it as the whole story is how projects get red-flagged in review.
- Editions
- Ed. 1 2017; Ed. 2 IEC 62619:2022 adds a thermal-runaway propagation test — check the edition on every certificate
- Test levels
- Type tests at cell, module and battery-system level; road EVs excluded
- Thermal abuse test
- Oven hold commonly cited at 85 degrees C
- External short circuit
- Applied at low resistance, order of tens of milliohms
- Propagation criterion (2022)
- Trigger runaway in one cell → no fire outside the enclosure, no explosion
- Chemistry data point
- Chemistry-neutral; LFP TR onset ~220–270 degrees C vs ~150–210 degrees C for NMC (format/SOC dependent)
- North American counterpart
- UL 1973 for stationary packs and racks — similar role, not interchangeable
- Layers above it
- UL 9540 (ESS listing), UL 9540A (fire test method), NFPA 855 (installation), NFPA 68/69 (explosion control)
- Companion IEC standards
- IEC 62620 (performance/marking), IEC 63056 (ESS-specific), IEC 62933-5-2 (system safety)
- Certification route
- IECEE CB scheme via accredited labs (TUV, UL Solutions, Intertek, SGS)
- Due-diligence check
- Match certificate edition + exact model/revision to the delivered BOM; demand the CB test report, not the one-page cert
- Substring trap
- 62619 = safety; 62620 = performance/marking — a 62620 cert proves nothing about abuse tolerance
Typical values and standards
The type-test matrix covers electrical, mechanical and thermal abuse. Cells face external short circuit at low resistance (tens of milliohms), impact, forced discharge and a thermal-abuse oven hold commonly cited at 85 degrees C, plus, where national rules require it, a forced internal short circuit test. Battery systems face overcharge, external short circuit and verification of the protective functions.
The 2022 edition added a defined Thermal runaway propagation test: runaway is triggered in one cell, and the pass criterion is no fire outside the enclosure and no explosion. That change reflects how storage scaled from single racks to gigawatt-hour campuses, where isolated cell failures are statistically expected over a 20-year life and graceful failure, not zero failure, is the target.
The standard is chemistry-neutral, but the numbers behind it explain why LFP dominates stationary BESS: thermal-runaway onset for LFP is commonly cited around 220–270 degrees C versus roughly 150–210 degrees C for NMC, depending on cell format and state of charge, and LFP's cathode does not release oxygen as it decomposes.
An engineer should name the layered set without hesitation: IEC 62619 plus IEC 63056 at cell, module and battery-product level, UL 1973 for stationary packs and racks in North America, UL 9540 as the ESS system listing and UL 9540A as the fire-propagation test method, then NFPA 855 with NFPA 68/69 at the installation. UN 38.3 sits alongside for transport, not for safety-in-service.
How it shows up in specs, studies and contracts
You meet IEC 62619 on the certification line of every serious cell and module datasheet, in employer's requirements and supply agreements as a condition precedent, and in lender and insurer due-diligence checklists. The working check is never "is there a certificate" but "what exactly does it cover."
Ask the vendor five things: which edition (a 2017 certificate predates the propagation test), the exact cell or module model and revision matched to the delivered bill of materials, whether the scope is cell-only or extends to the module and full battery system, which accredited laboratory issued it (TUV, UL Solutions, Intertek, SGS), and for the CB test report itself — not just the one-page certificate that hides the tested configuration.
In permitting, the certificate feeds the Hazard Mitigation Analysis and the AHJ submission as evidence of controlled cell-level failure, alongside the UL 9540A report that covers propagation at unit scale. In contracts, tie it to change control: a cell supplier swapping electrode vendor or capacity grade mid-delivery can silently invalidate the type test, so require notification and re-certification for any change that affects the certified design.
The binding constraint is the tested configuration — the charge rate, state of charge and pass criteria stated in the report — because that, not the certificate logo, is what a reviewing engineer has to defend to an insurer or an AHJ.
Common pitfalls
The classic trap is treating IEC 62619 and UL 1973 as interchangeable — they cover similar ground but differ in test detail and market acceptance, and an AHJ or a UL 9540 listing will expect the UL document in North America. A subtler substring trap is 62619 versus 62620: the latter is performance and marking, not safety, so a 62620 certificate proves nothing about abuse tolerance.
Edition drift is just as real — a 2017-edition certificate says nothing about propagation, which is decisive for any project leaning on cell-level containment claims. Read the number, the edition and the standard family, never just the presence of a logo on a datasheet.
Finally, do not read the 2022 propagation test as a substitute for system-level fire data. Passing single-cell Propagation inside one module says little about rack-to-rack spread, gas accumulation between the Lower Explosive Limit and Upper Explosive Limit, or Deflagration venting design in a full container — exactly the gap UL 9540A and NFPA 68/69 exist to close.
Emergency Response Plan content and firefighting guidance likewise come from the system and installation layers, not from the battery-product certificate. Put plainly: IEC 62619 proves the cell fails gracefully; it does not prove the container does, and only the layers above it can.
If the cells are IEC 62619 certified, the BESS is fire-safe and compliant to install.
In reality: IEC 62619 certifies only cell-, module- and battery-product-level safety — essentially that one cell fails without cascading inside its own enclosure. It says nothing about container-scale fire spread, which the UL 9540A test method characterises, nor about the system listing (UL 9540) or the siting, suppression and separation rules of NFPA 855 with NFPA 68/69. All of those must be satisfied separately before an Authority Having Jurisdiction will approve the installation.
- BESS Fire Safety: Thermal Runaway, NFPA 855, and What the Incidents Taught Us Article
- LFP vs NMC vs Sodium-Ion: Choosing a Battery Chemistry for Stationary Storage Article
- Interactive: Lithium-Ion Cell Interactive visual · bess.engineer
IEC 62619, in context.
The Grid-Scale BESS course covers iec 62619 — and the rest of the system — from the ground up, the way it actually gets deployed.