Originally Posted By: Donald
So what is difference about the construction of a low maint. battery vs a no maint. battery such that the no maint. battery never needs water to be added? Is a no maint. battey a SLA?
I have no desire to rip off plastic to get at the cells if the construction of the battery does not allow that.
Maintenance-free lead acid batteries are a Lead-Calcium chemistry. They lose much less water over time than lead antimony batteries, and also tend not to corrode the terminals as much due to less gassing.
These batteries are not AGM. They still have a liquid electrolyte.
Some lead-calcium batteries are maintenance accessible with removable caps... most Johnson Controls are, but there are exceptions. They still lose less water than lead-antimony, but should be checked occasionally.
Sealed batteries should have enough excess electrolyte to deal with any normal gassing and water loss for the life of the battery, assuming your car's charging system is functioning properly.