in my opinion one should only add acid to a battery under the following conditions
1. if the battery is a new dry charged unit
2. if the battery has been tipped over and lost its electrolyte, with a caveat
that the battery was fully charged before it was dumped,
if the battery was tipped over and dumped and you don't know if it was fully charged or not
i would refill it with distilled water and charge the thing until there is no further rise in specific gravity for
3 hours, then
dump the contents and refill with fresh electrolyte.
the problem with adding new acid to a used battery is you have no way of knowing how much acid is trapped in sulfation
without first recharging the battery fully, and then doing an equalization.
you mention a hydrometer that is scaled with white, red, green or whatever
that is about useless for proper battery maintenance, it will only give you a relative indication of condition but no where
near accurate enough to do what needs to be done.
get one that is scaled to three decimal places, so that it can read 1.265 for instance, and
it should include a temperature compensation chart.
charge the batteries fully before you do anything, then measure the specific
gravity of each cell and log the readings on a chart,
in the meantime, contact the manufacture of the battery and find out what the specific gravity for a fully charged battery
is supposed to be, not all manufactures use the same specific gravity, some will use stronger acid in order to get more power
from a battery at the expense of lifespan, and visa versa.
while you are talking to them, find out what their recommendation is for an equalization charge, how many volts and for how long.
keep the temps down to below about 110F, over about 120F and you can do damage to the battery.
the manufacture will tell you how far apart the cells can be in specific gravity before they need an equalization charge, follow their
recommendation and you will get the best results.
think long and hard before you fall into all the hype about adding some chemical or salt to the cells, or invest in a desulfator
there is little solid evidence that either are as effective as using a good charge routine, with an approved equalization, and there
is some evidence that adding some of these chemicals while temporarily improving the situation usually either reduce the lifespan
of the battery, ruin its efficiency, or increase their self discharge, or some/part or all of the above.
contrary to popular belief, battery manufactures want their product to perform as designed, and they want you to get the maximum
life out of them,
the economy is tough, and the competition in the battery market is extreme, if there were any trick chemicals or processes that
extended the life of their cells you can bet they would have been marketing the stuff for the last century.
stick with what the manufacture recommends will rarely lead you down the wrong path.
bob g
