Equalizing Formula (We'll Use A Pair Of Golf Car Batteries)

[MEXICOWANDERER]

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.

• 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.

[westend]

onecb wrote:
"•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." I bought one of the load testers and I really do not understand the test or the results when used on a pair of 6 volts? Could one of you knowledgable people explain it to me? Thanks Alvin

HF 500 amp tester manual (in case you don't have one).

You need to know the amp hour rating of one of the two identical 6V batteries. Connect the battery clamps from the tester to your batteries. Turn the "Load" knob on the tester until the left side analog meter reaches the amp hour rating. Wait 10-15 seconds and read the indicated scale on the right analog meter of the tester. It should point to the Green ranges if your batteries are good and charged.

[Canadian_Rainbi]

MEXICOWANDERER wrote:


Boy talk about aching fingers* causing the brain to fingers to short-circuit. Yes,.015 is correct my figure as listed is incorrect.

*Shoulders, knees, #4 lumbar disc, toenails, hair, etc.

My father used to joke: "What doesn't hurt doesn't work" Now I know he wasn't joking!

[onecb]

"•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." I bought one of the load testers and I really do not understand the test or the results when used on a pair of 6 volts? Could one of you knowledgable people explain it to me? Thanks Alvin

[Salvo]

Salvo's equalization differs from Mex's. 16V is too high in hot weather. You could destroy the batteries waiting for the voltage to get to 16V. At 80F, my golf cart batteries never get to 16V. During equalization, voltage does not rise continuously. Battery voltage will peak and then drop.

My procedure is to record battery voltage every 10 to 15 min. Once voltage peaks and is on decline, continue equalization for 2 hours.

Sal

MEXICOWANDERER wrote:

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.

If you are doing a single 6 volt battery apply 11 amps until 8 volts is reached

Redo the hydrometer check.

[mena661]

Works like a champ too. Haven't done a regular equalize in at least a year and a half.

[pianotuna]

Hi Snowman,

As Mex said

"Top charge is a mild equalization".

I believe it is to help prevent hard sulphate build up.

[KendallP]

Snowman9000 wrote:
So what is top charging, then? Just a quick bubbling to equalize the electrolyte?

More of a quick bubbling to break up sulfate on the plates and revert it back into solution.

[Snowman9000]

So what is top charging, then? Just a quick bubbling to equalize the electrolyte?

[MEXICOWANDERER]

Here I was on a beach way the heck and gone down Mexico way. My neighbor was having fits with his 4 8-D "high top" batteries.

His rig had one of those old NHE Onans, and his charger was a Magnatek 775-2 ferroresonant 75 amp charger. Not a "converter". He was ensconced in a remote parking spot, awning out, carpet laid, cobwebs gluing the wheels to the ground.

The old Magnateks used to put out 14.0 volts. It wasn't enough to zap those high tops (8-D high-tops were 1-1/2 8-D's tall).

Solution?

Turn off ALL the breakers. Connect the generator directly to the Magnatek. Tear off a matchbook cover. Shim the throttle on the NHE (volts per hertz). So what the generator was now running at 64 hertz? The Magnatek popped up to 14.8 volts and got the job done. The cost was prohibitive. Mexicans do not have matchbooks. I was out a matchbook cover.

Can't do that with this new-fangled crap. New stuff is so smart it out-stupid's itself.

[MEXICOWANDERER]

The best way to charge batteries is cell-by-cell. This is why 2-volt cells can be manipulated so much. That and .300" thick positive plates.

TOP CHARGING. Just to reach 15.00 Then pull the plug. If your battery is a hard nose and likes to sulfate fast, drop drop to 3% and do the same. Fifty three dollars for a VARIAC big enough to twist the HF charger's tail. Combine that with a nice Intermatic 6 hour spring wound mechanical timer and you have a genuine Mother Fletcher's Do it Yourself Sulfation Outsmarter...

[Matt_Colie]

Mex,

You are telling these people a lot of what I have been saying here and everywhere else. Thank You

One of the first things I was schooled about is not trying to change banks that are in parallel. It just doesn't work. Yes, I can explain why, but it is about a two beer talk.

I learned a lot about keeping batteries alive and well from a couple of WWII submariners when I sailed some long passages with them. They had hydrometers that you would probably die for... But they are no longer available.

Did you know that those submarines ran a still for battery water? They didn't have enough water to wash, but they made battery water.

For the last thirty years, I have used a refractometer. Temperature compensation is unnecessary. The first one I bought was not Chinese and was made to be a piece of laboratory equipment. I check its calibration occasionally, but it is still where it belongs.

Matt

[Snowman9000]

Mex, for top charging, how long to hold the batteries at 5%/15v?

[MrWizard]

i think you can count us as off grid heavy users
last time we plugged in was 11 months ago, last October

well we did have an overnighter 15 amp last week end, first time since last yr

not enough to carry the 100amp wfco, but did use the B&D at 20 amp setting
with fridge on shore power

i have to admit , we use them hard

[MEXICOWANDERER]

I would rather see plates undergo a light equalization than wait until specific gravity varies a lot then have to really hammer the plates to get the sulfation off. Once sulfation has hardened a little bit of the battery plate is lost forever.

This is why I am so persnickety about TOP CHARGING, bringing the batteries up to 15.0 volts at 5% of amp hour capacity amperage, at least once per month. This lessens the need to hammer in that extra volt which really erodes the plates a lot faster.

Don, you need to do a capacity test on your GC's or car jars. I do not like hauling around dead weight and less than 80% capacity left, to me is dead weight. Really thick plate batteries can shed lots of material and really active equalization can boil it up into solution. Then you will see gray. How much is "enough life left for me"? Only the individual can answer that for sure. But lost ampere hour capacity combined with smoky acid, and a battery that equalizes OK but then falls back into its old evil unequal densities at the drop of a hat is not a good sign.

"Lesser" meaning lower quality batteries will need equalization a lot more often and starting sooner than top of the line batteries. I am not going to get into a brand name discussion here, but too many el cheapos will go downhill fast.

The difference between someone who is a genuine off-grid heavy user is a completely different animal than a weekend casual user or a plug-in most of the timer. I have seen folks who were totally satisfied with a battery that had 20% of its capacity left, and actually bragged to friends about the "lifespan" of their choice of battery. A single cycle of that battery by a heavy user would see it on the recycle pallet the very next day.

This is why a lot of comments and bragging have to be taken with two grains of salt. Mix an electrochemical reaction with emotion and ego and you have quite a story for fantasy land.