The differences between Li-ion, Ni-Cd, and Ni-MH battery for LED Emergency Kit?

LED emergency conversion kit

As a power source, the battery pack is an essential part of each LED emergency power kit.

But many customers do not know what kind of LED emergency battery pack should choose for their LED lamp.

Some supplier’s driver can work only with a battery type for some reason, which will bring a lot of trouble when you want to change a battery pack in the future.

In the LED emergency industry, the basic is the LED emergency driver can work with all kinds of battery packs.

Here are the Battery packs that mainly used:

  1. Li-ion Battery Pack
  2. Ni-Cd Battery Pack
  3. Ni-Cd Battery Pack
  4. LiFeO4 Battery Pack
Ni-Cd Battery Pack

At the early time of the LED emergency conversion kit industry, we mainly use Ni-Cd battery as the power source.

Because the Ni-Cd battery is very safe from over-charge and over-discharge risk, so no matter how you use it, it will not encounter shortcut risk.

while the Lithium battery has a very short lifetime if you use it inappropriately as it can not be over-charged and over-discharged at all.

However, the Ni-cd battery has it’s drawbacks, that is it has an obvious memory effect.

So here comes a question: what is battery memory effect?

If the battery pack does not discharge to empty in this cycle, then the un-discharged part can not put out electricity in this cycle anymore.

such as if the battery pack left 20% capacity energy which did not discharge this time,  then there is only 80% battery capacity can put out electricity.

Many country’s policies require the LED emergency light should last at least 90 minutes.

But sometimes the city electricity may not cut off for that long, which caused the Ni-Cd battery to get battery memory effect.

And then the LED lamp can not meet 90minutes of emergency time next time.

But we also have way to remove the Ni-Cd battery’s memory effect simply just by discharging the Ni-Cd battery 3-5 times.

Then the battery pack will work normally.

What’s more, a single Ni-Cd battery’s voltage is only 1.2V, while a single Li-ion battery voltage is 3.7V.

If we want to get a 11.1v/12V emergency battery pack, we can only use 3pcs Li-ion battery, but need 10pcs Ni-Cd battery.

Even though a single Li-ion battery is more expensive than a single Ni-Cd battery, but if want to get a high voltage pack, a Ni-Cd battery pack will cost more.

But there are still many customers would like to take Ni-cd battery, the safety is the priority after all.

Ni-MH Battery

And then there comes the Ni-MH battery, which has improved the battery memory effect and based on the Ni-Cd battery pack.

Even the Ni-MH battery pack has a very small battery memory effect also, but we can add a battery control system to protect the battery pack to charge and discharge at some range.

The Ni-MH battery has 1.5-2 times energy density as much as Ni-Cd, which means the same battery energy capacity, the Ni-MH battery will have a smaller size.

The Ni-MH battery can contain the energy for a longer time than the Ni-Cd battery pack.

The Ni-MH battery pack is also safe and will not get explosion even when there is a shortcuit.

And the Ni-MH battery can work as much as 500 full charges and discharge cycles.

What’s more, the Ni-MH battery is much more environmental than the Ni-Cd battery pack.

Li-ion Battery and LeFePO4 battery pack

As mentioned above, the Lithium battery is not good for LED emergency light at the beginning.

Because they are easy to get over-charged and over-discharged, which is not safe for LED emergency kit.

However, Li-ion battery is now popular in the LED emergency industry.

The factories can now add a PCB protection board battery management system to protect the battery pack from over-charged and over-discharged.

And the battery management system is updating always in the LED emergency industry.

So it can inclreasely improve the safety of the Li-ion battery packs.

The biggest advantage of the Li-ion battery is it has a very high energy density, it takes much less space compared to the same energy capacity other battery packs.

And the Li-ion battery has a higher voltage than Ni-Cd and Ni-MH battery, so the Li-ion battery will cost less than Ni-Cd and Ni-MH battery.

The Li-ion battery has twice times the energy density than the LiFePO4 battery pack, so the volume of the LiFePO4 is twice as Li-ion battery pack.

So if the LED lamp has limited space for installing the LED emergency packs, we’d better use the Li-ion battery pack as the power source.

It’s just like the Tesla car uses the Li-ion battery pack while bus uses LiFePO4 battery as the power source. Car has a limited space while car has enough room for the battery packs.

But the LeFePO4 battery has its own advantage also, it has a longer life than the Li-ion battery pack.

And LeFePO4 battery pack can stand higher temperature than the Li-ion battery, if the LED lighting working environment has a high temperature, we advise you use the LeFePO4 battery or high temperature battery pack even.

But the Li-ion battery has better performance than the LiFePO4 battery in low-temperature environment.

In minus 20 degrees, the Li-ion battery can discharge 70% energy while the LiFePO4 battery can discharge 54% only.

What’s more, the LeFePO4 battery will not burn when it encounters shortcut also.


According to these information above, we can know that each kind of battery has its own advantage and disadvantage. We can’t refuse a battery for its short backs.

We need to select the battery pack based on our actual needs.