Batteries and Fire (Part 3 – Placement of Energy Storage Systems)

02/12/2025

When placing batteries, many different aspects need to be considered. Below, we review some of these important factors. Your installer is responsible for ensuring that the placement is done correctly, but to help you get an overview, we outline the key aspects here.

Keep in mind that regulations do not significantly differentiate between battery technologies, meaning that qapasity’s semi-solid state batteries are categorized in the same group as other lithium-ion batteries (and other chemistries as well).

Placement of Energy Storage Systems

Energy storage systems should be installed in accordance with the manufacturer’s installation instructions and with sufficient clearance in front of the inverter. The end customer should be informed about the battery’s location and noise levels to ensure that the system does not cause disturbance. If there is insufficient space, the customer should be notified before installation. The inverter and battery can be mounted on a façade if the manufacturer’s guidelines allow for it. It is important to follow requirements for non-combustible walls, protection from direct sunlight or heavy rainfall, and safe distance from ventilation systems.

Following the manufacturer’s instructions is crucial for both warranty coverage and fire risk management. While installation guidelines vary between manufacturers, certain general recommendations should always be observed. Although these apply primarily to “traditional” LFP batteries, many of the points are applicable to qapasity’s semi-solid state batteries and should especially be considered for indoor installations.

General Recommendations

Temperature: Batteries should ideally be placed in a cool environment, preferably between 5-15°C. Temperature affects both battery performance and lifespan. Charging and discharging may be limited if the battery is too cold.
Access: All batteries should be accessible from the doorway or an equivalent entry point for fire suppression. In commercial buildings and apartment complexes, battery rooms should have direct access to an exterior door.
Fire containment: If possible, batteries should be placed in a separate fire compartment. The storage space should meet at least fire resistance class EI 60.
Drainage: The room should have a floor drain to prevent water damage in case of a fire.
Smoke ventilation: Consider installing smoke ventilation in larger battery storage areas to reduce the risk of toxic smoke spreading within the building.
Fire detection: Install smoke detectors or fire alarms. The energy storage system should be integrated with the building’s active fire protection systems, such as automatic alarms and sprinklers. Additional fire protection may be required for larger battery installations if the building lacks these systems.
Documentation and labeling: The battery’s chemistry and system structure must be clearly indicated. Information on fire department shut-off options and recommended extinguishing methods should also be provided. Wiring diagrams and fire response instructions must be available.

New Building Regulations (from July 1, 2025)

Currently, Sweden’s building regulations do not include specific rules for stationary batteries. However, new safety regulations related to battery energy storage systems over 20 kWh are planned to take effect on July 1, 2025. The proposal includes three new sections.

Chapter 5 § 21a: Rooms with batteries over 20 kWh must be designed as a fire compartment, unless the fire risk has minimal impact on evacuation safety.
Chapter 5 § 25: Rooms with batteries over 20 kWh connected to an internal evacuation route must include a fire lock unless the area is rarely used by a few people.
Chapter 8 § 11: These rooms must have smoke ventilation, except for fire compartments smaller than 10 m². The openings should not obstruct evacuation routes or other operations.

Geometric Requirements for Ventilation Openings:

At least 0.5% of net area without a sprinkler system.
At least 0.1% of net area with a sprinkler system.
Each opening must be at least 0.7 m².
Smoke ventilation in underground rooms must be operable from an external control point.

Guidelines for Battery Fire Protection (Svensk Solenergi)

In 2024, the Swedish Solar Energy Association published guidelines for fire protection during battery installation. These guidelines specify that they are not tailored to semi-solid state technology. They state:
“There are also batteries without flammable electrolytes, such as solid state batteries. These are not covered by these guidelines. Fire protection measures for such batteries should follow the manufacturer’s instructions and an individual risk assessment.”

Although not fully applicable to qapasity’s Arctic Series, many of the recommendations are sound and should be considered, particularly for indoor installations.

Specific Placement Recommendations

Residential Properties:
For residential installations, there are no specific regulatory requirements (until the new regulations come into effect on July 1, 2025). Instead, recommendations from insurance companies and fire services apply. Common installation locations include basements (in technical or boiler rooms) or heated garages. Thanks to the integrated heating in qapasity’s Arctic Series, the system can also be placed outdoors. It is strongly recommended to install the battery in a separate fire compartment, such as a detached garage or a separate room with fire resistance class EI 60.

Agricultural Properties:
The following rules are based on LBK Section 5. The battery system should be installed in a non-combustible container or a building designed specifically for battery storage with fire resistance class EI 60. The container or building should be at least 15 meters from other structures. If placed over 30 meters away, no fire compartmentalization is required. Second-life batteries are not allowed. For battery systems up to 25 kWh, placement in a separate room within an existing building is permitted if the following requirements are met:

The room must not be located in a building housing animals.
The room must have at least one exterior wall.
The room must meet fire resistance class EI 60 on both sides.
The door must be installed in the exterior wall and meet fire class EI 60.
Second-life batteries are not allowed.

Heating and ventilation for the space, where the battery is to be installed must be evaluated to fit the system and the regulations. Ventilation is also important to evacuate gases in the case of malfunction.

Lessons from a Battery Fire in Örebro

In June 2019, a battery fire occurred at a school in Örebro due to a short circuit. Although no one was injured, several critical issues were identified:

There was no clear emergency response plan.
Firefighters hesitated due to uncertainty about the battery chemistry, although water would have sufficed since it was not a lithium-ion battery fire.
The wait to enter was too long, as they did not know which battery chemistry that was in the building.
There was no proper drainage for water
The facility lacked proper ventilation for smoke.
Both the fire department and property owner had limited knowledge of the system’s design.

Tips for a Successful Battery Installation

Plan the battery placement carefully, considering factors like temperature, humidity, and dust.
Equip the room with smoke detectors, a floor drain, and proper ventilation.
Ensure the room meets fire resistance class EI 60.
Follow the manufacturer’s instructions and manuals.
Maintain proper documentation.
Hire a certified electrician with the appropriate expertise.
Consider outdoor installation if the battery can operate in cold temperatures, such as qapasity’s Arctic Series.

Conclusion

The Örebro battery fire highlighted important lessons regarding system design, documentation, and training. As energy storage becomes an integral part of building energy systems, it places greater demands on designers, installers, and even firefighters.

Battery fires remain rare but can be catastrophic if installations are not properly designed. The installer is a crucial partner for the end customer, responsible for craftsmanship, system design, and commissioning. It’s essential to select a qualified installer you can trust, with the right training to handle energy storage systems.

qapasity strongly advises consulting experts when installing energy storage systems and prioritizing safety. Review requirements from authorities such as the fire department to ensure both safety and compliance. It’s easier to do things right from the start by consulting experts before installation. Don’t hesitate to reach out to us for advice on battery installations or to get in touch with a skilled installer in your area.

More Information: