Does Storing Lithium-Ion Batteries Change Sprinkler Design?

Yes. Storing lithium-ion batteries in a warehouse changes the sprinkler design in almost every case, because NFPA 13, the National Fire Protection Association (NFPA) Standard for the Installation of Sprinkler Systems, has no prescriptive protection scheme for them. The 2022 edition’s annex commodity table (Table A.20.4(a)) lists lithium-ion batteries as outside the standard’s protection scope, so a ceiling-only design picked from the storage tables cannot be shown to cover them. The design instead comes from an alternative, engineered approach under NFPA 13 Chapter 24, or from insurer guidance such as FM Global Data Sheet 7-112 (Lithium-Ion Battery Manufacturing and Storage), accepted by the authority having jurisdiction (AHJ).

How far the design has to move depends on 6 factors: the quantity stored, the state of charge, the packaging, the storage height, the share of the array the batteries occupy, and what the existing sprinkler system was designed for. This article is the storage angle on that question for a warehouse or distribution center in New York, New Jersey, Pennsylvania, Maryland or Delaware. The permit and code-trigger side, including the 2024 International Fire Code (IFC) Section 320 rules, comes in here only as far as it shapes the sprinkler design. Energy storage systems that are installed and operating fall under NFPA 855 and are a different subject, not covered here.

Why NFPA 13 Has No Table for Lithium-Ion Batteries

NFPA 13 protects storage by classifying the commodity, then reading a ceiling design or an in-rack arrangement from the tables for that class, storage height and ceiling height. The classification chapter (Chapter 20 in the 2019, 2022 and 2025 editions) sorts goods into Class I through Class IV and Group A plastics, with cartoned and exposed, expanded and unexpanded subdivisions. Lithium-ion batteries have no class. The 2022 annex commodity table (Table A.20.4(a)) lists them as outside the scope of NFPA 13 protection criteria. DGA’s article on how commodity classification works under NFPA 13 explains the class system the batteries fall outside of.

The reason is the fire behavior. A cell in thermal runaway releases its own flammable electrolyte vapor and heat, so the fire does not depend on the oxygen and fuel geometry that the commodity tables were built on. Large-scale tests run by FM Global and the Fire Protection Research Foundation on cartoned lithium-ion cells in rack storage between 2013 and 2016 (Fire Protection Research Foundation, Lithium-Ion Batteries Hazard and Use Assessment, Phases II and III) showed that a standard ceiling-only design could control fires in some arrangements, mainly small cells in cartons at limited heights and low state of charge, and could not be relied on for bulk storage without more sprinklers, barriers or in-rack protection.

That leaves two routes in the standard itself. NFPA 13 Chapter 24, Alternative Sprinkler System Designs for Storage Applications, allows designs based on full-scale fire tests or on listings for a specific commodity and arrangement. The other route is the code’s alternative materials and methods clause, IBC Section 104.11 and IFC Section 104.10 in the 2021 editions or Section 104.2.3 in the 2024 editions, under which the fire code official can accept an engineered design, most often one that follows FM Global Data Sheet 7-112.

What Thresholds Change the Sprinkler Design?

No single number turns the design on or off. The table lists the 6 factors a fire protection engineer measures, the thresholds that appear in the 2024 IFC and in FM Global guidance, and where each one comes from. The FM Global values are paraphrased from the current data sheet and are checked against it on every project.

How Is the Lithium-Ion Hazard Measured?

The measurement starts with an inventory, not a sprinkler calculation. The fire protection engineer lists every lithium-ion item by chemistry (lithium iron phosphate, nickel manganese cobalt and the others behave differently), by watt-hour capacity per cell or pack, by state of charge as received and as stored, by packaging at each level, and by where and how high the items sit in the array. The inventory also records whether the batteries arrive installed in a product, such as a power tool or an e-bike, or as loose cells and packs for assembly.

The engineer then applies a commodity approach. FM Global Data Sheet 7-112 treats lithium-ion cells, modules and products as a hazard in their own right, and sorts them by state of charge, packaging and arrangement into scenarios that each point to a protection scheme, from a quick-response ceiling-only design through the expanded plastic criteria to in-rack sprinklers with barriers (paraphrased). The 2024 IFC adds the quantity test: the cubic feet of batteries in the fire area, net of the products they are installed in. For a mixed commodity, NFPA 13 Chapter 20 governs how a minority of higher-hazard goods is treated, and the engineer documents the percentage and the dispersion.

Someone has to sign the classification. In every state DGA works in, the high-piled storage plan and the sprinkler design basis are sealed by a licensed Professional Engineer (PE) or, for the sprinkler layout, prepared by a contractor under NFPA 13 Chapter 28 (Chapter 27 in 2019) and reviewed by the engineer of record. The AHJ accepts the classification; the insurer’s field engineer usually reviews the same inventory against the data sheet. Getting the two to agree on the inventory before the design starts avoids a redesign later.

Where Does 2024 IFC Section 320 Apply in the Region?

Section 320 is new in the 2024 IFC, so it applies only where the 2024 edition has been adopted. In the DGA states that means New York State outside New York City. Everywhere else the AHJ decides under the general alternative methods clause and the high-piled storage chapter. The table shows the position in each jurisdiction as of October 2026.

Editions as listed in DGA’s Fire Code Cheat Sheet for NY, NJ, PA, MD and DE. Local amendments are not shown.

DGA classifies commodities, prepares high-piled storage plans and designs storage sprinkler systems across New York, New Jersey, Pennsylvania, Maryland and Delaware. Project briefs get confirmation and preliminary code feedback within one business day. See where DGA works →

Exceptions and Alternatives to a Full Redesign

Several conditions keep a lithium-ion storage project inside the existing sprinkler design, or limit how far the design has to move. None of them is automatic; each one has to be documented in the high-piled storage plan and accepted by the AHJ.

• Small quantities. Below the 15 cubic foot threshold in a fire area, the 2024 IFC Section 320 provisions do not apply, and most AHJs on older codes accept that a few pallets dispersed in a mixed commodity do not change the design. The quantity still has to be counted and stated on the plan.
• Batteries installed in products. The 2024 IFC excludes new or refurbished batteries installed in the equipment they power, and batteries packed with that equipment, from Section 320. Some AHJs extend that logic and treat power tools, consumer electronics and small appliances as their parent commodity, often cartoned unexpanded Group A plastics. E-bikes and larger packs are less often accepted that way, and the position varies by reviewer.
• Segregated low-SOC storage. A dedicated area holding cells at or below 30 percent state of charge is the easiest case to protect. The 2024 IFC waives the technical report, 2-hour separation and explosion control at that level, and FM Global’s least demanding scheme applies below its break point. The operator has to be able to show the state of charge, so this works for distribution of new product, not for returns.
• In-rack sprinklers and vertical or horizontal barriers. Where a ceiling design cannot be shown to work, in-rack sprinklers with horizontal barriers at set intervals usually can, and they keep the fire in the rack where it started. DGA’s article on when in-rack sprinklers are required covers the arrangements.
• Detection and early response. Aspirating smoke detection or thermal imaging that catches off-gassing before ignition is part of the 2024 IFC Section 320.4 indoor requirements and is often what an insurer asks for first. Detection supplements the sprinklers; it does not replace them.
• Outdoor or detached storage. Moving the batteries to a detached structure or a protected outdoor area takes the hazard out of the main warehouse. The 2024 IFC Section 320.4.3 sets separation distances and pile limits for outdoor storage, and the main building’s design then stands as it is.

What Applies Once the Design Changes?

Once the inventory shows lithium-ion storage the existing design does not cover, the project becomes an engineered sprinkler design rather than a table lookup. The engineer selects the basis, either an FM Global Data Sheet 7-112 scheme matched to the scenario or a design supported by full-scale fire tests for the same cell size, packaging and arrangement, and documents it under NFPA 13 Chapter 24. The ceiling-only schemes in the data sheet call for large-orifice quick-response sprinklers at a set pressure over a 12-sprinkler design area, and the in-rack schemes call for specific K-factors, barrier spacing and a minimum number of operating heads (paraphrased).

The paperwork follows the design. A technical opinion and report, prepared by a qualified engineer and submitted under IFC Section 104.8.2 (2021) or 104.2.2 (2024), explains the hazard and the basis to the fire code official. The high-piled storage plan is updated with the battery area, the commodity classification and the new design criteria, and the plan’s companion article on how storage height drives the ceiling sprinkler design shows how the height limits in the scheme translate to the racks. Where heads, barriers or pipe sizes change, a sprinkler alteration permit is filed with the building department.

Water supply is the cost item owners miss. A 12-sprinkler design of K-25.2 heads at 35 psi flows well over 1,500 gpm before hose allowance, and in-rack sprinklers add to that demand, so a warehouse designed for a Class III commodity at 0.2 gpm per sq ft often finds its fire pump or city main short. A current hydrant flow test and a water supply analysis belong at the start of the project, not after the sprinkler layout is drawn. DGA’s industrial and high-hazard sector page describes how these projects are staffed.

Code Minimum vs What Insurers Expect

The fire code sets a floor, and for lithium-ion storage that floor is thin: outside New York State, the adopted codes in the region have no battery-specific sprinkler requirement at all, and even Section 320 defers the design to what the fire code official accepts. Property insurers do not leave the question open. FM Global Data Sheet 7-112, Lithium-Ion Battery Manufacturing and Storage, issued in October 2024 and carrying forward the storage criteria that were in Data Sheet 8-1, gives its field engineers a scheme for each storage scenario and a list of conditions that move the account to in-rack protection, and other carriers borrow it. An insured warehouse will usually be held to the data sheet whatever the AHJ accepts.

The practical consequence is that the insurer’s data sheet, not the code, usually sets the design on a lithium-ion storage project in New Jersey, Pennsylvania, Maryland and Delaware. Bringing the carrier’s engineer into the first design meeting, alongside the fire marshal, is the shortest path to a design both will accept.

Frequently Asked Questions

This article is general information, not a substitute for a project-specific commodity classification and sprinkler design. Code editions, insurer data sheets and reviewer practice change; confirm the adopted code, the insurer’s current requirements and the authority having jurisdiction for the project.