Batteries & Energy Storage Systems (ESS)

Lithium-ion batteries are rechargeable batteries known for their lightweight and long-lasting properties. They can be found in electric vehicles and battery energy storage systems (ESS), as well as smaller devices including e-bikes, e-scooters, cell phones, computers and hoverboards. Despite their wide range of uses in commercial and residential settings, these technologies present unique safety challenges. 

New innovations and battery chemistries continue to be developed, challenging manufacturers, code officials and consumers to stay up-to-date on operational best practices of the technology.

Learn how codes, standards and guidelines are adapting to support the safe use, manufacture, storage, use and recycling of batteries and ESS, and find key resources to help ensure protection for installers, code officials, system designers, retailers and everyday users.

Battery and ESS Basics: What You Need to Know

From personal electronics to mobility devices, the consumer demand for reliable stored energy is drastically increasing. These needs are further increased by the desire for more clean energy in the automotive sector as well as the growing demand for improvements to our utility systems and the need for more stored energy.

As the development, manufacture and use of these batteries increases, attention to the storage, handling, disposal and recycling of new and aged battery units is crucial to ensure health and safety in the built environment and develop future code considerations that address battery chemistries and technologies.

To ensure performance, longevity and safety, it’s critical to follow best practices throughout the lifecycle of lithium-ion batteries and ESS.

business man on scooter with helmut

eldery woman on sit down scooter

children in a classroom using laptop computers

Failure

Lithium-ion batteries can fail for many reasons including improper manufacturing, damage to the battery and, in some cases, the improper charging of devices.

Lithium-ion battery failure may be caused by either an internal or external condition:

  • Internal failure is a result of a short circuit within the cell, called thermal runaway.
  • External failure may be caused by incompatibility between the battery and a connected charger, damage to the battery or exposure to extreme heat or cold.

An ensuing failure causes cell chemical off-gassing, very high temperatures, smoke and fire. When batteries fail there can be little or no early indications. When one cell fails as part of a battery pack, it could create an uncontrolled chain reaction where additional cells are damaged and then have a thermal event of their own. The gas that is produced as part of a thermal event is typically toxic and flammable in most cases.

Manufacturing and Processing

Over the past two decades, battery manufacturing facilities within the built environment have been limited. However, they are now rapidly expanding due to the high demand for batteries in energy storage, electric vehicles and mobility devices.

Best Practices:

  • Facilities and associated equipment should be regularly maintained and cleaned
  • Ensure batteries undergo necessary testing to detect defects and thermal instability before distribution
  • Maintain a quality assurance program to remove weak or defective cells before assembly
  • Adopt the most current International Codes® (I-Codes) to ensure building and fire safety requirements are met
  • Develop special emergency procedures for incident management and battery decommissioning as part of the facility’s emergency action plan

Installation and Use

Battery retailers, installers and users of ESS and battery-powered devices can help reduce the risk of a battery fire by following safe practices.

Best Practices:

  • Look for the Underwriters Laboratory (UL) mark on battery-powered devices that shows it has been tested to nationally recognized safety standards
  • Follow manufacturer’s instructions for the use, charging and maintenance of the battery
  • Installation of ESS should be performed by licensed professionals following local codes, standards and the manufacturer’s instructions
  • Ensure proper ventilation around the ESS to prevent overheating
  • Do not attempt to modify or disassembly batteries or ESS
  • Avoid exposing batteries to high heat, water or physical shock
  • Use only manufacturer-approved batteries, chargers and cables for your device
  • Avoid overcharging batteries, unplug the device as soon as it has completed charging
  • Inspect the battery for any signs of damage, leaking, increased heat or smoking. If you see any signs, immediately stop using the battery and place safely away from other combustibles

Storage

After manufacturing, batteries are stored in preparation for transportation, distribution and use. Safety strategies in storage buildings and areas help reduce the potential fires from expanding.

Best Practices:

  • Storage facilities must have adequate fire protection systems coverage that is designed to suppress a developing battery fire
  • Store batteries in a cool, dry and well-ventilated area, away from direct sunlight and flammable materials
  • Storage of batteries that have less than 30 percent state of charge may be considered less volatile

Disposal and Recycling

Replacing a battery when it comes to the end of its lifecycle or becomes damaged includes proper and safe disposal of the old battery. Some disposal and recycling facilities process batteries and extract their components for reuse.

Best Practices:

  • Never use damaged batteries
  • Dispose the battery at a certified recycling or disposal center, do not place it in a standard trash container
  • Be careful of handling damaged batteries after a fire incident as the batteries may cause a secondary fire caused by the damage
  • Contact your local battery recycling drop-off site to receive easy instructions for disposal

Batteries in Emergency Planning and Response

Many U.S. states and other countries have experienced a significant surge in fires associated with lithium-ion batteries.

The use of lithium-ion batteries as ESS in our homes can create a potential need for early identification in post incident mitigation and evaluation. Containment, collection and disposal of batteries impacted by a disaster, especially involving fire or flood, takes much care and consideration as part of the response and recovery phases of disaster management.

Training emergency responders and managers to stay up to date in codes, regulations and best practices of battery handling is critical to maintain community awareness and safety. This is especially crucial after a disaster when damaged batteries are left in homes and buildings affected by the disaster.

The Code Council’s When Disaster Strikes (WDS) Institute prepares participants to properly evaluate damage through instruction, interactive activities and review of case studies. The goals of the WDS Institute are to increase the number of trained and qualified Post-Disaster Building Safety Evaluators and Post-Disaster Building Safety Evaluation Coordinators and to increase awareness regarding when and how to perform Post-Disaster Building Safety Evaluations. Learn more here.

Codes and Standards

Adopting and implementing current building codes and standards ensures that lithium-ion batteries and ESS are installed, operated and maintained safely to minimize risks of fire, electrical hazards and system failures.

The International Code Council (ICC), through its membership, code action committees and the code development process, has rapidly developed the I-Codes since the 2015 editions of the International Fire Code® (IFC), International Building Code® (IBC) and International Residential Code® (IRC) to incorporate the evolving and advancing battery chemistries and technologies. These codes and standards incorporate the latest research and best practices, helping protect both occupants and first responders while supporting the safe integration of advanced energy technologies.

Over the past two code development cycles, the collaborative efforts of ICC Code Action Committees and various Code Development Committees have established and enhanced a minimum level of battery safety across the built environment.

This progress is evident in the 2024 suite of I-Codes including the IFC, IBC and IRC as shown in the ESS Development Time frame recap below.

2000-2015

Early Considerations for Battery Storage and Fire Safety

2018

IBC/IFC: Initial Recognition of Lithium-Ion and Emerging Technologies

2018

IBC/IFC: Expansion of Fire Protection Requirements for Energy Storage

2021

IBC/IFC/IRC: Refining ESS Regulations and Integration of Large-Scale Systems

2024

IBC/IFC/IRC: A Comprehensive Framework for ESS in the Built Environment

See Complete Timeline

Resources

The ICC Ad-Hoc Battery and Energy Storage Committee's efforts are documented in this comprehensive report that includes how and where batteries and ESS are used in the built environment, details the committee's code gap analysis approach, highlights areas of focus within future I-Codes, examines professional training and community education needs, and explains necessary public awareness strategies for maintenance and charging of personal mobility devices.