Lead Acid Battery Charging, Maintenance Tips

The post discusses some of the crucial parameters related to lead acid battery charging and maintenance for ensuring longer life to the device. The questions were asked by Mr. Raja Gilse, answered by me.

Q1: What is the full charge volt of the 12 v 110 ah deep cycle lead acid battery at the time of charging? Sir, I am confused. All your article about battery charging you told that, it lies between 13.5 and 14 volt. I read in some other web sites that, it is 14.4 volt for deep cycle battery  after this point gassing starts. Please confirm me whether this battery high voltage differs with the AHC of battery? I am asking so deeply because, I have a 12 V 110 ah battery in my house for solar lighting system by the SELCO solar light private ltd, from past 10 years. The charging panel is of 75 watt. They had maintained 15 V as battery high in their charge regulator. I had noticed that at this level gassing starts in the battery, which slowly spoils battery  So now I made a charger by help of your blog, Now, I am in dilemma to set the bty high volt. So please confirm me the battery high voltage. 

A1: It should be normally and ideally between 14V and 14.4V, never above this value. After this level the battery should be applied with a trickle charge voltage or the specified float voltage.

Q2: What is equalization charge of battery? Is it to give charge up to 15 volt?? Or something else. What is the periodicity of equalization ? Please guide me for my battery's good health.

A2: These are extra maintenance procedures, it's a kind of desulfation of the battery, these procedures will not be required if the battery is charged through a step charger circuit as explained here:

http://homemadecircuitsandschematics.blogspot.in/2012/10/make-this-3-step-automatic-battery.html

More sophisticated step charger designs can be made by including more number of steps, I'll discuss it soon in one of my upcoming posts.

Q3: As you suggested in one of your comments that the 3 step automatic charger is suitable for up to 40Ah battery. But mine is 110AH battery  So i can't use that. Another thing, further to my earlier email about "battery charging", Which is important thing in bty charging, is it the charging voltage or the charging current? Or both? I am asking so. Because, in my home, the solar charging panel gives voltage up to 21 volt and 4.5 amps at mid noon. Is it safe for my 12 V 110 ah battery  I read that the max charging volt will not exceed 15 volt . Is it true? Or as the charging current is only 4.5 ah , i.e. Very much less than C/10, it is safe to charge in 21 volt ?? Therefore I asked which is important voltage or current? And also in trickle charge , which is important, is it to maintain the charging current as C/100 Or charging voltage as 13.5 ?

A3: It's current that is important, 4.5A will not do any harm to your 110AH battery at 21V as long as it's being charged, however once your battery becomes fully charged then this voltage/current might start causing some concern to your battery, so it's better to keep things regulated and under control. The same goes for trickle charging also, once the battery becomes fully charged maintaining correct voltage (14.4) becomes crucial.

Tweet