Overview of Emergency Battery Backup

Portable electronic equipment is moving toward increasing compactness and lightweight, and we are on the threshold of the age of wearable equipment. In such circumstances, the rechargeable batteries which power such equipment play an increasingly vital role, and in addition to demands for reduced size and weight, there are now also requests for performance necessary to support the sophisticated functions of modern equipment.

And now, rechargeable batteries also are widely applied for emergency backup led lighting. Lightide Manufactory Co., Ltd. (LMC) mainly focuses on quality led lighting manufacturing. So we also use rechargeable batteries for led garage & canopy lighting, led high bay and led wall packs lighting. But sometimes peoples are confused about how to choose emergency battery type and it is difficult to decide a suitable emergency battery power and time. Here we would like to describe many kinds of batteries for emergency backup led lighting

EMERGENCY-battery-led-vapor-tight-lights

Types of Batteries

Batteries can be sorted into 3 categories: lithium-ion (Li) battery (LIB), alkaline battery and nickel–metal hydride (Ni-MH) battery. Now we usually use rechargeable Lithium-ion, Li-FePO4 and Ni-MH battery for emergency backup led lighting. 

Lithium-ion Batteries (LIB)

Lithium-ion batteries (LIB) are common in consumer electronics. They are one of the most popular types of rechargeable battery for portable electronics, with one of the best energy densities, no memory effect, and only a slow loss of charge when not in use. Beyond consumer electronics, LIBs are also growing in popularity for military, electric vehicle, and aerospace applications. Research is yielding a stream of improvements to traditional LIB technology, focusing on energy density, durability, cost, and intrinsic safety.

Now emergency battery Li-ion usually is used for indoor led lighting. The emergency power can be from 3 watts to 20 watts. The emergency time is 1.5 hrs ~3 hrs. 

Comment: Very high specific energy,  limited specific power. Market share has stabilized.

EMERGENCY Lithium-ion battery for led lights

Lithium iron phosphate (LiFePO4 ) battery

The lithium iron phosphate battery (LiFePO4 battery) or LFP battery, is a type of rechargeable battery, specifically a lithium-ion battery, using LiFeP4 as the cathode material, and a graphitic carbon electrode with a metallic backing as the anode. The LiFePO4 battery uses lithium-ion-derived chemistry and shares many advantages and disadvantages with other lithium-ion battery chemistries. However, there are significant differences. LFP chemistry offers a longer cycle life than other lithium-ion approaches.

LMC’ Emergency battery Li-Fe PO4 can be used for indoor or outdoor led lighting. The emergency power can be from 8 watts to 20 watts. The emergency time is 1.5 hrs  (90 minutes). 

Comment: Flat discharge voltage, high power low capacity, very safe and elevated self-discharge.

Emergency Li-Fe PO4 battery for led Wallpack light

Nickel–Metal Hydride (Ni-MH) batteries

A nickel–metal hydride cell, abbreviated NiMH or Ni-MH, is a type of rechargeable battery. It is very similar to the nickel-cadmium cell (Ni-Cd). NiMH uses positive electrodes of nickel oxyhydroxide (Ni-OOH), like the Ni-Cd, but the negative electrode uses a hydrogen-absorbing alloy instead of cadmium. A NiMH battery can have two to three times the capacity of an equivalent size Ni-Cd, and their energy density approaches that of a lithium-ion cell.

LMC’ Emergency battery Ni-MH usually is used for indoor or outdoor led lighting in the North American. The emergency power can be from 3 watts to 20 watts. Emergency time usually is 1.5 hrs  (90 minutes). 

Comment: Has higher capacity, less maintenance. 

Emergency Ni-MH battery for led CANOPY light

Emergency Battery Comparison For LED Lighting

BatteryLithium-ionLi-Fe P04Ni-MH
Specific Energy150–200Wh/kg90–120Wh/kg60–120Wh/kg
Volume ComparisonSmallBigBig
Weight ComparisonLightHeavyHeavy
Suitable Work Temp (OC)  0-3545-5555-70
Cost

Cheap

ExpensiveExpensive
Cycle Durability400-1200 cycles1000-2000 cycles>500 cycles

How to choose Emergency battery for led lighting?

From the above descriptions, we know the difference between these batteries. So next we here recommend a simple method to choose a suitable battery for our emergency backup led lighting step by step.

1. Emergency battery type option

Please check the circumstance temperature (working temp.) of the battery. If it is used for indoor emergency backup led lighting below room temperature 35OC,  Lithium battery should be the best option. If the room temperature is 45~55 oC, we can choose Li-Fe PO4 battery. Otherwise, we may choose a Ni-MH battery to work at a more higher temperature. 

 2. Decide Emergency time 

In general, emergency work time standard is about 3 hours for the European market and 1.5 hours for the North American market. Of course, it also is up to your customer’ requirement. For example, LMC’ DLC QPL emergency led canopy lights, the emergency work time is 1.5 hrs (90 minutes).

3. Confirm Emergency Power

Emergency work power, in general, is decided about 10%~20% of the total power of fixture in Europe. For example, the power of led high bay light is 150 watts, so let’s decide the emergency power is 15~30 watts.  But for North America, the emergency power will be asked about 20%~30% of the total power of fixture.  

led-garage-canpy-emergency-light

Except for the above, we also have to consider the light intensity during emergency mode to match with emergency lighting standard. Please contact us for more detail. 

 

Lightide Manufactory Co., Ltd. 

2019-06

Any questions, please tell us. We would like to help you.