19/06/2023
The security industry has for a long time adopted the Sealed Lead Acid Battery as the standard for backup power to alarm panels.
The 12V 7AH Sealed Lead Acid or Gel batteries are the most commonly used on alarm panel installations. They have unfortunately run into a problem called..... Eskom.
Under stage 6 rolling blackouts, some areas spend 10 hours a day without electricity. Every time the battery is discharged when the power is turned off, it loses a part of its capacity.
In some alarm installations, the battery is fully discharged, and never returns to its original capacity. A battery which was lasting the SAIDSA recommended 6 hours, now starts lasting 5 hours, 4 hours, 3 hours …. , and the entire alarm installation may turn off during a power outage.
How much capacity the battery loses depends on:
• The quality of the battery
• The quality of the charger
• The current consumed by the alarm installation
• Whether the alarm panel cuts-out at a certain point to preserve the battery life
Lead acid batteries also do not like the high temperatures in our roofs in the African sun.
ENTER THE LITHIUM-ION BATTERY
There is a replacement for the standard lead acid battery in the same size and
capacity. The standard replacement is called a Lithium iron phosphate (LifePO4). It can endure thousands of charge and discharge cycles before losing its capacity.
> Isn’t it dangerous?
LiFePO4 are the safest type of lithium battery because they are not prone to overheating and even if they're punctured, they won't catch on fire.
> Isn’t it environmentally hazardous?
The cathode material is also non-hazardous and therefore it poses no environmental or negative health hazards.
> What are the pitfalls?
It costs more - as simple as that.
THERE ARE SOME ISSUES WITH DIRECTLY REPLACING A LEAD-ACID WITH A LITHIUM-ION BATTERY
> The charger:
Lithium-Ion batteries require a higher charge voltage than lead acid to obtain their full capacity (typically 14.6V as opposed to 13.7V)
> Low Battery Measurement:
The alarm panel will report a low battery condition when the battery reaches a certain voltage .The SAIDSA minimum voltage is 10.2V, but this differs from one alarm panel to another. Normally it is slightly higher. The voltage of the Lead Acid battery degrades as it is discharged.