Equalizing Formula (We'll Use A Pair Of Golf Car Batteries)
You need to get an accurate hydrometer. Without one you are blind. Might as well trying to determine if a person has high blood pressure by having them stick out their tongue.
I hope to get a 3 amp VARIAC soon. They cost fifty some odd dollars and with a VARIAC I can play a charger like a pipe organ. Maintain 10-11 amps with precision.
My fingers are aching. I hope this becomes a sticky. I would get censored if I wrote what I think of arthritis.
- Disconnect negative cables from 12 volt side
- Fill all cells with distilled water
- If you have a PARALLEL set of batteries, unparallel them:Wait overnight
- Measure voltage across positive and negative terminals of EACH battery separately. It does not matter if they are 6 or 12 volt. MEASURE and write it down!
- If a pair of 12 volt batteries differ by more than .3 volts or one 6 volt differs by more than .15 volt note which battery has what. Low batteries need more careful inspection
- Charge each battery at 10 amps until every single cell in that battery is bubbling. Stop the charge then go on to the next battery
- It's better to charge 6 volt batteries independently rather than in a series pair
- With all batteries fully charged let the battery temperature return to normal
- Hydrometer test each cell independently
- Write each cell down. A diagram figure showing cells is the easiest way to remember
- If you draw a sample and the electrolyte is SMOKY cloudy end of test for that battery. It's doomed. Same for a reddish tint
- Do all the cells
- I do hope you are wearing safety glasses and latex kitchen gloves right? You do have a ready made up jug of baking soda mixed with water, right?
- The hydrometer bobber MUST float freely within the glass tube. Tilt the hydrometer upright to let the bobber run up and down freely
- Did you remember your reading glasses and fit them under the safety glasses?
- Every cell on your diagram should have a number next to it.
- If any two cells in one battery have a .15, that's point one five difference between the highest and lowest cell, it's due to be equalized
- Cull that battery from the bunch and MARK the low cell with a marking pen or splotch of paint or whatever
- If you have a pair of Golf Car batteries that each have a .15 spread in density you may consider connecting them in series just like you have them in the coach to make 12 volts.
- Take your time! Make sure they are connected in series!
- A pair of golf car batteries can be charged at 11 amps. This is not easy to achieve nor to sustain but do the best you can
- Amperage will drop and voltage will rise as the equalization process continues
- When a series pair of batteries reaches 16.0 volts stop the charging. Go to the next battery or batteries and let the first ones cool off.
- This is why record keeping is so important
- Repeat the exercise on the 2nd set of batteries.
- If you are doing a single 6 volt battery apply 11 amps until 8 volts is reached
- Redo the hydrometer check.
- If any cell did not return to 1.275 or 1.280 you have a troublemaker on your hands
- If the battery is fairly new and had been abused, repeat the 11 amps equalization charge
- If the battery is more than 3 years old it's dying.
- How soon it's going to die is anyone's guess, but batteries that do not recover fully are not up to doing full task work
- The harder a battery is to equalize and the faster the cells become unequal in gravity the closer it gets to the recycling center. You can count on it.
- Harbor Freight sells an inexpensive 500 amp adjustable load test machine. I love it as doing a load test alongside a hydrometer inspection and equalization is a great dose of truth serum.
- Get proficient doing this and charge fellow RV'ers to do their batteries. No one else does this right so you'll be the exclusive agent in your area.
I hope to get a 3 amp VARIAC soon. They cost fifty some odd dollars and with a VARIAC I can play a charger like a pipe organ. Maintain 10-11 amps with precision.
My fingers are aching. I hope this becomes a sticky. I would get censored if I wrote what I think of arthritis.
