Golf cart batteries CG2 water levels

[Rover]

After checking my batteries (8 cg2's) I'm curious to what others use for an appropriate water level over the plates when fully charged.

(6 Volt, golf cart batteries).

Saw one level from Trojan which stated 1/8 inch below the fill well, this seems quite high to me. Others say 1/4 to 3/4" off the plates...

feedback desired

[Wolvenar]

My batteries have slits on each side of the fill wells
I have always kept them about at the top of those slits 
I picked up a set of caps for one of the batteries that seem to keep it just about there as well.
I'll be getting more of those caps as time and $ permits, but stuck doing it by had yet until then I suppose.

[WooferHound]

I'm pretty sure that as long as the plates are not exposed to the air you are OK.
 - But -
The water levels change with the state of charge, the more the battery is discharged the lower the water will get. Equalizing the battery will cause the water to get as high as possible. Not to mention evaporation and gassing.

Just like Wolv, I have the slits in the side of the fill wells. I fill them up to the bottom of the slits when the battery is at full charge. I would be afraid to fill them up to the top of the slits because equalizing might cause the water to expand out of the fill holes and overflow.

[madlabs]

Same, to the bottom of the fill well. Never had any overflow issues.

How often do y'all fill and how much? I seem to be at about twice a year and takes about 3/4 gallon for ten batteries.

Jonathan

[Wolvenar]

So far its been very rare mine ever "boil" over filled where I have them.
Yeah its happened though in a case where the inverter was equalizing after the day before had a power outage, which caused a fairly deep discharge.
Even then it was barely anything and just on top of the batteries. with the self filler tops, I doubt even that would happen.

When this setup was acting as just a backup system I had te batteries in a shed that would get rather warm. I would go through about a gallon every couple months easily until winter, which then I never used more than a quart (if that) every couple months.

Since the move into a shaded little battery enclosure built just for them and re purposed for solar and an offgrid system alone, I have used about the same as I normally did in the winter months. But I have only added water once so far, checkup is due any day now

[Rover]

I know of bunch of battery maintenance links ... happened across this one. Which I'm sure others have found. But it provides detail of which many do not.

http://usabatterysales.com/cat-battery-facts-other-useful-information.cfm

I don't own stock in USA Batteries, and there is no conflict of interest.

Rover

[MadScientist267]

All of my flooded batteries also have the slits, and filling them up to the bottom of the slit does not seem to be an issue as long as 2 conditions are met:

1. As Woof pointed out, don't add water when they are discharged. I'm inclined based on a couple observations I've had with mine in the past however to even go as far as to agree with the concept of adding during equalization. Even if you have to initiate one just for the purpose of watering. Reason being is that this is ultimately where the highest water levels will ever be observed, and the bubbling will only add to the effective height. Once the cells reach a modest tempurature during EQ, fill em up. Another is that striation (tendency of water and acid to separate because the acid is heavier) will be reduced due to the bubbling stirring the electrolyte. This avoids uneven "wear" of the plates in the cells.

2. I tend to target just slightly below the slit for the simple fact that depending on the size of the battery and the container your water is in, it can be easy to get them too high, invariably leading to electrolyte loss. It will either come up out of the vents during a later charge, or when you go to correct your mistake on an immediate level by sucking some of it back out. There are 2 significant problems with this happening:

    A. If you go the "let it overflow" route, those who have had it happen know that its not a one time event to clean up the mess before the top of the battery also overflows and the acid goes elsewhere and does whatever its going to do when it gets there. It can take multiple neutralization/soakup sessions before it gets back down low enough that the overflowing stops.

    B. You can't predict to any precision how much electrolyte will be lost based solely on how much extra water was put into the cell if the overflow method is allowed to take place, and if you go with the "suck it back out" method, you (ideally) need to overfill each cell by the same amount before you go to remove it. Cell imbalance will either start or get worse when the specific gravity gets out of whack from cell to cell, leading to premature failure of the battery as a whole when the weakest cell succumbs to the extra stress and abuse it will endure in the charge/discharge cycles to come.

All of that being said, I stay in the 1/8" range away from the bottom of the slit, particularly on the smaller batteries. If you're dealing with a forklift battery, gallon jugs filled with your distilled will obviously be less of an issue.

Steve

[philb]

On August, 1st, I topped my 6 volt GC2 batteries up to the ring. All read within 100th of one volt.

The batteries were purchased 4 each time. The first four, January 2011, then February 2011 and the last set were purchased June 2011.

The first four and the second four are in series. The last four are in parallel with the second set.

The batteries were checked at the end of the day, when the Classic 200 had the batteries floating.
The loads (when I'm not working) are a small refrigerator and a temperature controlled exhaust fan. The total load for most days is 2.4 kW. When I'm working, 3.8 kW, so The batteries are not loaded heavily at any time. They seldom fall below 25.0 volts (24 volt system).

I checked them Sept. 2nd. Here's the results:

battery #      voltage     added water?
1                    6.33               y
2                    6.36               y
3                    6.34               y
4                    6.37               n
5                    6.35               y
6                    6.36               y
7                    6.37               n
8                    6.37               n
9                    6.37               n
10                  6.37               n
11                  6.35               y
12                  6.37               n

I added half a gallon of water on this check. It has been 120 degrees F in the containers almost every day.

The only conclusion I can draw from the data currently is if the voltage is less than 6.37, it will need additional water.

[Watt]

Thank you for your post.

Could you post a picture or a wiring diagram of your battery set? 

Thanks again.

On August, 1st, I topped my 6 volt GC2 batteries up to the ring. All read within 100th of one volt.

The batteries were purchased 4 each time. The first four, January 2011, then February 2011 and the last set were purchased June 2011.

The first four and the second four are in series. The last four are in parallel with the second set.

The batteries were checked at the end of the day, when the Classic 200 had the batteries floating.
The loads (when I'm not working) are a small refrigerator and a temperature controlled exhaust fan. The total load for most days is 2.4 kW. When I'm working, 3.8 kW, so The batteries are not loaded heavily at any time. They seldom fall below 25.0 volts (24 volt system).

I checked them Sept. 2nd. Here's the results:

battery #      voltage     added water?
1                    6.33               y
2                    6.36               y
3                    6.34               y
4                    6.37               n
5                    6.35               y
6                    6.36               y
7                    6.37               n
8                    6.37               n
9                    6.37               n
10                  6.37               n
11                  6.35               y
12                  6.37               n

I added half a gallon of water on this check. It has been 120 degrees F in the containers almost every day.

The only conclusion I can draw from the data currently is if the voltage is less than 6.37, it will need additional water.

[philb]

I don't have the picture thing down very well Watt. I'd better stop while I'm slightly ahead for now..

Batteries 1 to 4 are in series.
Batteries 5 to 8 are in series.
Batteries 9 to 12 are in parallel. I connected positive to positive and neg to neg to batteries 5 to 8.

Ok, the link works.

[philb]

I did my monthly check of the battery voltage and specific gravity. My batteries have shown  readings in the 6.33 volt range since they were new.

I started running low on battery juice earlier this month due to cloudy weather. For the first time, I hooked my 8000 watt generator to the Outback inverters to help keep the voltage up. To my surprise, the voltage rose up to 28.8 and stayed there for several hours after I killed the generator.

Now the batteries maintain a higher float charge than before, as this month's check indicates. Apparently, the batteries never reached the full capacity until I  held them at the higher voltage with my generator. I had no idea when I purchased the batteries of exactly where the float voltage should be because I couldn't find anything published. After all they are golf cart batteries.

I have not changed the battery configuration between the two monthly readings. 1 to 4 in series, 5 to 8 series, with 9 to 12 in parallel to numbers 5 to 8.

Batt #   check dates            
   09/01/12      10/02/12      
1   6.33                 6.43      
2   6.36                  6.45      
3   6.34                 6.46      
4   6.37                 6.46      
5   6.35                 6.44      
6   6.36                6.44      
7   6.37                 6.46      
8   6.37                 6.45      
9   6.37                 6.44      
10   6.37                6.44      
11   6.35                6.45      
12   6.37                6.45      

[bj]

   Interesting Phil.  I have no idea why though.  The good thing is that you haven't made a whole bunch of other
changes, which would confuse things.
   It will be interesting to see if the increase in voltage is long lasting, or just a short term thing.
   It will also be interesting to see what happens the next time you top them up using the genset.
   As I said interesting, most interesting.
   

[philb]

I've had fits with Chrome. It does use less Gb per month than FireFox and IE.
Anyway, here is a rough diagram of my battery setup.

[Norm]

Here's a subtle thought about water level.....
  There are some that are young enough to never have
known cars that had batteries that were not "maintenance free"
I'm guilty of having cars with batteries that needed the water checked
ever so often....never checking until the car wouldn't start....."did you
check the water in the battery?" ......sure enough one or two cells the
top of the plates would be exposed.....it was one of these times I learned
that there were slits in the bottom of the fill hole tubes and just putting
even tap water to the top of the slits was sufficient and the motor would
kick over.....
ever since then whenever the solenoid went bad, the starter motor , corroded
terminals, etc.   and that sweet lovely voice would ask...." Honey ....did you
check the water in the battery? "

Ya gotta love 'em !   

and BTW...I have never known any one of my "unmaintainence-free" not to have these slits ?

Norm.
this is my only experiences with water level.....nothing about
float level....voltage...specific gravity etc.
 

[bj]

  You are absolutely right about the slits Norm, and some of the "un-maintenance free" commercial
ones still have it.  I always considered it the full mark.  (the few times I remembered to check)