Equalize batteries on a "small" sailboat

Posted By: walt26scolorado
Date: 4/11/09 8:07p.m.

Report: outside forum guidelines

You can find lots of info on equalizing batteries (google knows many things) and I cut and pasted from a web site some info about equalizing at the bottom of this post. Ive overall kept my batteries charged but was terrible BAD about checking and maintaining the fluid levels - didnt do this for two years on wet cell batteries and had to add a fair amount of water when I finally checked. In my defense, it was a pain to get to the batteries but that has now been fixed. This spring, I had fully charged my batteries and I felt the "output resistance" of the batteries was lower than normal (ie, the voltage of the battery drops more than it did in the past when a load was put on the battery). The batteries seem to be behaving a little better now that it has warmed up but Im wondering if I need to equalize the batteries (and of course check the fluid more often). None of the charging methods on my boat will equalize (battery maintainer, solar panel or outboard alternator). I went to the hardware store thinking that I could buy a battery charger with an equilizer feature but none had this. Does anyone actually equilize their batteries? If so, what equipement do you use? My batteries are Walmart deep cycle wet cell. --------------------------- Flooded battery life can be extended if an equalizing charge is applied every 10 to 40 days. This is a charge that is about 10% higher than normal full charge voltage, and is applied for about 2 to 16 hours. This makes sure that all the cells are equally charged, and the gas bubbles mix the electrolyte. If the liquid in standard wet cells is not mixed, the electrolyte becomes "stratified". You can have very strong solution at the top, and very weak at the bottom of the cell. With stratification, you can test a battery with a hydrometer and get readings that are quite a ways off. If you cannot equalize for some reason, you should let the battery sit for at least 24 hours and then use the hydrometer. AGM and gelled should be equalized 2-4 times a year at most - check the manufacturers recommendations, especially on gelled.