I have a 12 V 6 Ah lead acid battery, and have been instructed to charge it using a configurable power source.
They told me I should use a float charge, setting the voltage at a fixed level according to the battery datasheet, and end the charge when the charging current is lower than about 5% C (5% of 6A in this case).
Doing this, I have barely gotten about 80% of the rated capacity. Now, doing some research on my own I've found that what I should really do is a cycle charge, which as I understand it is a constant current charge until voltage reaches a higher level than with the float charge (also specified in the datasheet).
Long story short is, what is the proper way I should charge this kinds of batteries? Should I do constant voltage then constant current, just constant current, whatever? What I really wanna do is understand how to evaluate a given battery.