Curtis controller

[ThreeCW]

Originally Posted by Papa5

ThreeCW These are Duracell GC2 75 Amp 105 minutes Golf Car Batteries and made in USA Should I wait 24 hours before doing any reading Thanks

The 20 hour rating of your batteries is 215 amp hours.

Your battery voltage should be stabilized (or nearly so) if you wait 24 hours after fully charging and disconnecting your charger. For the sake of science, record each battery voltage at 12 hours and 24 hours after charging to see if there is much of a difference (if you are into science ).

Any time after 24 hours should give you a reasonably stabilized reading for state of charge determination.

[Papa5]

ThreeCW , Thanks for the info I will record the findings and get back with you after 24 hours , just curious should all 6 batteries read the same thru charging process because I have 2 that are off always and does it charge the batteries in sequence because the 2 that are off always is the one that the red lead from the charger is connected to and the next one is right behind it

[cgtech]

Perhaps 12v lights are attached to those 2 batteries? That's the most common cause of battery imbalance.

[Cobra,1]

Not unusual to see tenth a volt between batteries.
What is hydrometer reading after full charge batteries at rest.

Another guestion. Are your 12 volt accessories being supplied via convertor or 12 volt acessories connected to 2 batteries. Makes a difference in balance.

[ThreeCW]

In a perfect world, if the batteries are of the same model and condition, they should charge at the same voltage across each battery.

If some batteries are weaker than others, they will likely charge at a somewhat different voltage.

In my old battery pack where I had replaced 3 of the pack of 8 with “good used” or “new blemished”, the replacement batteries would charge at somewhat higher voltages (0.3 to 0.4 v I recall) than the original members of the pack. I also recall that after stabilization that all the batteries settled to 100% state of charge and were within 0.2 volts of each other. The replacement batteries were a slightly lower amp hour rating than the originals.

[Papa5]

Everyone , here is my findings , 39 - 38.6 - 38.5 battery - 1 =6.4 6.3 6.3 Battery 2 = 6.4 6.4 6.3 Battery 3 = 6.5 6.4 6.4 Battery 4 = 6.5 6.4 6.4 Battery 5 = 6.5 6.4 6.4 Battery 6 = 6.4 6.4 6.3 The first # dropped to that # as soon as the charger stopped The second # Is after 12 hours and the third # is after 24 hours FYI , before the charger cut off it was at 42.5 and 4 batteries was 7.0 and 2 was at 6.9 Appreciate any help in this , trying to figure out why the cart struggles to make it on inclines ,

[JohnnieB]

The at-rest voltages look reasonable.

After you get the clip leads, measure the voltages while going up an incline.

What drive system do you have, series or sepex (PDS)?

How tall are the tires? (stock is 18" tall)

Do any of the cables get hot after climbing hills?

[Papa5]

OK did a check today , It was 38.3 and 5 of the batteries Is 6.3 and 1 is 6.4 and bought a decent hydrometer and 2 of the batteries on all cells showed 1.150 and the other 4 batteries was in the range of 1.210 , 1.225 and 1.250 I do not know what this means good or bad ??? also I have a series and the tires is 22-11-10 Still trying to find the leads with alligator clips on the end so I can test it on the inclines

[JohnnieB]

Not sure what the SG of Duracell batteries should be, but a variation of 0.030 or more between cells isn't good.

If you can lay your hands on a 6V charger, individually charge the lower ones up to the same SG as the highest ones. Or use a 12V charger and do the lower ones in pairs.

Then do some back-to-back charges with your 36V charger.

[Papa5]

JohnnieB Does it matter if the cables are connected to the smaller posts of the battery or would it be better to connect them to the larger ones , I took the batteries to the place I bought them from and they said all was good so now I am confused cause the auto parts said that two will not take a charge and also I went to home depot and bought leads with alligator clips but it was the wrong connection to the voltmeter I am still trying to get the voltage checked up the incline