SLA Battery - Constant voltage charging

[sundar-edaboard]

Hi,

The Battery Model is TSLA 1.2-12T
12V 1.2Ah Sealed Lead-Acid Battery

Charging Instruction at 20 dec C
DC Power, Constant Voltage charge, Initial Current : 0.36A MAX

Discharge/Charge Time	100%	50%	Charging Voltage
Standby Use	24h	20h	13.5-13.8V
Cycle Use	16h	10h	14.4-15.0V

1. What is the term meaning of initial current, standby Use, cycle use charging voltage?
2. What is constant voltage power supply i should use to charge this battery in 24x7?

 

[schmitt trigger]

A simple, two mode charger:

SLA batteries when discharged, must be charged with a constant current. In your example, it should be no larger than 0.36 amp, or the battery may vent. I would use 10% lower current if you live in a very warm climate (which I assume Bahrain has).

Once that the battery voltage reaches a certain value, the charger reverts to a constant voltage mode, and the remaining charge is applied to the battery.
Since you are using this battery in standby emergency mode (I base my assumption on your statement that it is connected 24X7), then choose between 13.5 to 13.8 volt. Again, in warm climates, choose the lower voltage.

This simple charging algorithm can be refined significantly, but if you want to experiment with chargers, it is a good starting point.

 

[betwixt]

The point is that if you connect a solid voltage from the charger to a fully discharged battery, it will draw excessive current and probably vent hydrogen gas and moisture. At the start of charging you limit the current to prevent that happening but as the charge builds up it is best to limit the voltage and let the battery take what it wants until it is 'full'.

Brian.

 

[--BawA--]

Don't use constant voltage charging solely,
Use atleast two stage charging CC/CV. it will help you to maintain battery health.you can use LM317 to achieve this.