Emergency Light Batteries

Emergency light batteries are a crucial component of building safety systems, providing necessary illumination during power outages or other emergencies.

These batteries ensure that exit routes are visible and safe to navigate, significantly reducing the risk of accidents and enhancing the ability to evacuate buildings quickly and efficiently.

Published: April 24, 2024.

Understanding Emergency Light Batteries

Emergency light systems rely on robust batteries capable of delivering reliable power in the event of an emergency. The most common types of batteries used in these systems include:

• Lead-Acid Batteries: Widely used due to their cost-effectiveness and reliability. They are heavier and require regular maintenance but are well-suited for stationary emergency systems.
• Nickel-Cadmium (NiCd) Batteries: Known for their durability and excellent performance in extreme temperatures, NiCd batteries are more expensive but offer a longer lifespan and better energy density than lead-acid batteries.
• Lithium-Ion Batteries: These batteries provide a high energy density and a long lifecycle with minimal maintenance. They are typically more expensive upfront but can be more cost-effective over time due to their longevity and efficiency.

Basic Principles of Operation

Emergency light batteries store electrical energy and provide it to the lighting system when a power failure is detected. This switch to battery power happens automatically, thanks to a transfer device that senses power outages and activates the emergency lights.

The capacity and efficiency of these batteries determine how long the lights can remain on during an emergency.

NiCd vs. NiMH Emergency Light Batteries

NiMH (Nickel-Metal Hydride) batteries do have certain attributes that lend themselves well to specific applications in emergency lighting, particularly in emergency conversion kits. Despite the popularity of NiCd (Nickel-Cadmium) batteries in these systems, NiMH batteries offer advantages that can be significant depending on the specific requirements and environmental factors of the installation.

One of the primary advantages of NiMH batteries is their environmental friendliness compared to NiCd batteries. NiMH batteries do not contain toxic heavy metals such as cadmium, which is highly toxic and presents disposal and recycling challenges. This makes NiMH batteries a more environmentally sustainable choice, which is particularly appealing in contexts where environmental regulations are strict or where companies prioritize green initiatives.

Additionally, NiMH batteries have a higher energy density than NiCd batteries. This means they can store more energy for their size or weight, which is an advantage in emergency lighting systems where space and weight are constraints, such as in portable or compact emergency conversion kits. The higher energy density of NiMH batteries can provide longer illumination times or allow for smaller, lighter battery units that are easier to install and maintain.

NiMH batteries also exhibit a less pronounced memory effect compared to NiCd batteries. The memory effect in NiCd batteries can lead to reduced battery capacity if they are not fully discharged before recharging. NiMH batteries, while still susceptible to the memory effect, are less affected and thus can offer more reliable performance in applications where the battery discharge cycles vary in length.

Also, advances in NiMH battery technology have improved their charge retention and overall lifespan, enhancing their usability in emergency lighting. These improvements mean that NiMH batteries can now more effectively meet the demands of emergency lighting systems, maintaining charge for longer periods when not in use and providing reliable power when needed.

While NiCd batteries are commonly used in emergency lighting systems due to their robustness and cost-effectiveness, NiMH batteries offer advantages in terms of environmental impact, energy density, and reduced memory effect.

These benefits make NiMH batteries suitable for use in emergency conversion kits where these characteristics are highly valued. This can make them particularly appealing for newer installations or upgrades in environments where these factors are prioritized.

Choosing the Right Battery for Your Emergency Lights

Selecting the right battery for emergency lights involves understanding the specific needs of the installation site, as well as the capabilities of different battery types:

• Capacity: The battery should have enough capacity to power the emergency lights for the duration required by local safety codes, typically at least 90 minutes.
• Lifecycle: Consider the expected lifespan of the battery and how often it will need to be replaced. Each type of battery offers different lifecycles and maintenance needs.
• Environmental Conditions: Some batteries perform better in colder or hotter environments than others. For instance, NiCd batteries are excellent for extreme conditions, whereas lead-acid and lithium-ion batteries may require temperature-controlled environments to function optimally.

Comparison of Battery Types for Different Applications

• Residential Buildings: Lead-acid batteries are often sufficient for small-scale systems where cost is a significant factor.
• Commercial Facilities: NiCd or lithium-ion batteries might be preferred in larger buildings for their longevity and reliability, especially in facilities with critical needs, such as hospitals and schools.
• Industrial Settings: Lithium-ion batteries are ideal for demanding environments due to their durability, maintenance-free nature, and compact size.

Choosing the appropriate battery involves balancing these factors with budgetary constraints to ensure that emergency lighting systems are both effective and economical. This selection process is critical to guaranteeing that safety systems function seamlessly when needed the most.

Of course, if you already have an emergency lights system and you need a new battery or battery pack, check the manual/instructions and go for recommended models.

Battery Sizes Used in Emergency Lighting Systems

Emergency lighting systems typically utilize a range of battery sizes to meet specific power needs and space constraints. The choice of battery size depends on the design of the system, the duration of emergency illumination required, and the installation environment.

Sealed Lead-Acid Batteries:

These are among the most commonly used batteries in emergency lighting due to their reliability and cost-effectiveness. Standard sizes for these batteries include:

• 6V 4.5Ah: Often used in smaller or less demanding installations.
• 12V 7Ah: Commonly found in many standard emergency lighting units, providing a good balance of size and capacity.
• 12V 12Ah, 12V 15Ah, and 12V 18Ah: Used in larger systems that require longer run times or are powering more extensive lighting arrays.

Nickel-Cadmium (NiCd) Batteries

NiCd batteries are used in emergency lighting for their high durability and performance in a wide range of temperatures. Common sizes include:

• Sub-C size cells (about 22mm in diameter and 43mm in length), often assembled into battery packs of various voltages and capacities.
• Custom-configured packs that might range from 2.4V to 12V, tailored to specific equipment requirements.

Nickel-Metal Hydride (NiMH) Batteries

Similar to NiCd, NiMH batteries can be found in standard sizes or custom packs for emergency lighting systems - like NiCd, common configurations use standard cells such as AA, AAA, or Sub-C, configured into necessary voltage and capacity.

Lithium-Ion Batteries

Lithium-ion technology, which offers higher energy density, is becoming more common in emergency lighting. These are often custom battery packs based on 18650, 21700, 26650, or even 32650 batteries, designed to fit specific systems, with voltages typically ranging from 3.7V to 14.8V depending on the system design.

Choosing the Right Size/Capacity

When choosing the battery size for an emergency lighting system, factors such as the required emergency lighting duration (commonly 90 minutes as per many safety standards), the total power consumption of the lighting fixtures, and the physical space available for battery installation must be considered.

The battery must be capable of powering the emergency lights for the duration required by local regulations, typically at least 90 minutes in the event of a power outage.

In addition, the installation environment can affect the battery size choice; for example, high-temperature areas may require batteries like NiCd that can withstand such conditions better than other types.

Installation Guidelines

Proper installation of emergency light batteries is essential to ensure they function correctly during an emergency. Follow these step-by-step instructions to install your emergency light batteries safely:

• Preparation: Ensure all power to the unit is turned off before beginning installation to avoid any electrical hazards.
• Access the Battery Compartment: Open the emergency light unit according to the manufacturer’s instructions to access the battery compartment.
• Remove Old Battery: If replacing a battery, disconnect and carefully remove the old battery. Dispose of it according to local regulations.
• Check Connections: Inspect all wires and connectors for any signs of wear or damage. Replace any faulty components as needed.
• Install New Battery: Place the new battery in the compartment. Make sure it is securely seated and oriented correctly according to polarity.
• Connect Wires: Connect the battery terminals, ensuring that connections are tight and secure. Double-check that positive and negative terminals are correctly matched to the unit’s wiring.
• Test the Unit: Once the battery is installed, turn on the power to the unit and activate the test switch to ensure the lights operate as expected.
• Close the Unit: Securely close the battery compartment and the unit.

Common Mistakes to Avoid

• Incorrect Battery Type: Ensure the battery type and specifications match those required by the emergency light unit.
• Loose Connections: Loose battery connections can lead to poor performance or failure in an emergency.
• Ignoring Polarity: Reversing the battery terminals can cause damage to both the battery and the emergency lighting system.

Again, check the Owner's Guide of the emergency lighting system and look for and follow the exact battery replacement procedures.

Maintenance and Testing Procedures

Regular maintenance and testing are crucial to ensure the reliability of emergency light batteries.

Maintenance Tasks

• Visual Inspections: Regularly inspect batteries for any signs of damage or leakage. Check for corrosion around terminals and connections.
• Clean Connections: Keep battery terminals and connections clean and free from corrosion. Use a cloth or brush to clean off any debris or buildup.
• Ensure Proper Charging: Check that the charging system is functioning correctly and that batteries are maintaining charge as expected.

Performance Testing

• Monthly Tests: Conduct short functional tests monthly by simulating a power outage or using the test button. This ensures the lights turn on and are adequately bright.
• Annual Tests: Perform a full discharge test annually, where the emergency lights should operate on battery power for the full duration required by regulations (typically 90 minutes).

Troubleshooting Common Battery Issues

Encountering issues with emergency light batteries can be common; knowing how to troubleshoot these problems is essential.

Common Problems and Solutions

• Battery Not Charging: Check charger connections and power supply. Replace the charger if necessary. Test the battery voltage to determine if the battery itself is faulty.
• Swelling or Leakage: Battery swelling can be a sign of overcharging or failure. Replace swollen or leaking batteries immediately to prevent damage to the emergency lighting unit.
• Reduced Backup Time: If the battery does not last for its intended duration during tests, it may be nearing the end of its useful life. Consider replacing the battery if it consistently falls short of the required backup time.

Installation, maintenance, and troubleshooting guidelines and procedures provided by the unit's manufacturer, ensure that the emergency light batteries provide reliable service and that the safety systems function effectively when needed most.

Emergency Lighting Battery Replacement

Timely replacement of emergency light batteries is crucial for ensuring that your safety systems function correctly during an emergency. Recognizing the signs that a battery needs replacing can prevent failures when you least expect them.

Signs That Indicate a Battery Needs Replacing

• Dimmed Lighting: If the emergency lights appear dimmer than usual, it may indicate that the battery is unable to hold a full charge.
• Shortened Run Time: During routine tests, if the lights turn off before the required duration has elapsed, it's a strong sign that the battery's capacity has degraded.
• Physical Damage: Swelling, leakage, or corrosion around the battery terminals are clear indicators that the battery should be replaced.
• Age: Most emergency light batteries have a recommended service life, which can range from 4 to 5 years. Replacing batteries at or before this time frame ensures reliability.

Guidelines on How to Properly Replace and Dispose of Old Batteries

• Turn Off Power: Ensure that all power to the unit is shut off to avoid any risk of electrical shock.
• Remove the Old Battery: Carefully disconnect and remove the old battery from the emergency lighting unit.
• Dispose Properly: Do not dispose of batteries in regular trash. Batteries contain materials that can be harmful to the environment. Check with local waste management services for guidelines on disposing of batteries safely.
• Install the New Battery: Place the new battery in the unit, ensuring it fits securely and the connections match the correct polarity.
• Test the Unit: Once installed, turn the power back on and test the unit to ensure functionality.

Safety Precautions and Best Practices

Handling and maintaining batteries safely is vital to prevent accidents and ensure compliance with legal and safety regulations.

Safety Measures

• Wear Protective Gear: Always use gloves and eye protection when handling batteries to protect against acid leaks and sparks.
• Proper Handling: Avoid dropping or jarring batteries, as this can cause internal damage and lead to battery failure.
• Ventilation: When charging batteries, ensure adequate ventilation to prevent the accumulation of potentially explosive gases.

Legal and Safety Compliance

• Regular Inspections: Conduct regular inspections and maintenance as mandated by local safety codes.
• Compliance with Standards: Ensure all emergency lighting systems meet national and international standards such as NFPA 101, Life Safety Code, and OSHA requirements.
• Documentation: Keep records of maintenance, inspections, and battery replacements to demonstrate compliance during safety audits.

Frequently Asked Questions (FAQ)

Here are some of the most common Frequently Asked Questions about emergency lighting batteries and emergency lights in general.

How does an emergency light work?

Emergency lights are designed to provide illumination automatically in the event of a power outage.

They are typically connected to the building's power supply, which keeps their internal batteries charged. When a power failure is detected, a circuit within the emergency light activates, switching the power source from the main supply to the battery.

This allows the emergency lights to continue operating independently, providing critical lighting along exit paths and other essential areas to facilitate safe evacuation.

The lights remain on until power is restored or the battery is discharged.

How often should emergency light batteries be replaced?

Emergency light batteries should typically be replaced every 4 to 5 years, but this can vary based on the type of battery and the conditions of use. Always refer to the manufacturer's guidelines.

Can I replace the emergency light batteries myself?

Yes, batteries can often be replaced by the user. However, it's important to follow safety guidelines, use the correct type of battery, and ensure proper installation.

Why do my emergency lights flicker when testing the battery?

Flickering during testing can indicate a battery is near the end of its life or issues with connections. Consider replacing the battery or checking all connections.

Are there any environmentally friendly options for emergency light batteries?

Yes, lithium-ion batteries are more environmentally friendly compared to lead-acid and NiCd batteries due to their longer lifespan and absence of heavy metals like cadmium.

Few Final Words

 Emergency light batteries play a very important role in safety systems, ensuring illumination during critical situations to facilitate safe evacuations.

Maintaining these systems is not just about regulatory compliance; it’s about ensuring peace of mind and safety for all occupants in any facility.

Regular checks, timely replacements, and staying informed about technological advancements are crucial steps in ensuring that emergency lighting systems function optimally when needed the most.

When looking for a new emergency light battery, be sure to go for the battery type and model officially supported by the unit that you have - better safe than sorry.