Nominal voltage of golf cart batts

[GILow]

Originally Posted by OldManMirage

Well, I was hoping for a more definite answer based on voltage, but I get it. Basically I'm trying to decide if it's worth the effort to lug a pair down to the boat and sweat them into place. Where I have to put them it will NOT be easy!!! So I may just wait until I'm ready to fork out the dough for a new pair.



Although I am really curious. Wish I has a 12volt load sitting around the house here somewhere..hmmm...then I could test a pair and see...

A couple of car headlight globes would work. If you have a soldering iron just keep adding globes in parallel until you get the required 20 amps. No need to take the batteries down to thr boat yet.

If you don't have a soldering iron now is a very good time to buy one because you'll need it soon enough.

[smac999]

an old battery will still charge up full.

it just won't have any capacity when used / drained.

fully charged and full capacity is 2 totally different things.

you need to do an c20 ah test.

[Uncle Bob]

Originally Posted by smac999

an old battery will still charge up full.

it just won't have any capacity when used / drained.

fully charged and full capacity is 2 totally different things.

you need to do an c20 ah test.

+1 I have just replaced my golf cart batteries, they reached a good voltage however held very little capacity. I replaced like for like, can't complain as I got a shade over 8 years out of the old ones.

[MicHughV]

The big draw of Golf Cart batteries is their ability to be drawn down and charged back up far more numerous times than a regular 12v bat.

They are constructed a bit taller than a standard 12v bat. which makes finding a spot for them.

I switched to 6v bats some years ago, and have never looked back since.

[Scorpius]

1. Charge them fully
2. Put them in the trunk of your car.
3. Connect them up in series to get one 12v battery.
4. Take them to a battery shop and get them to test them properly.

They'll probably just bring the tester out to your car and do it in a few minutes. I expect they'll do it for nothing (always have for me) if there is the prospect of selling you new ones if these prove to be shot.

[Niall leslie]

The fully charged voltage of a nominal 6 volt DC lead acid accumulator or 'battery' is 6.3 V. +-.
For a 12 V. unit it is 12.6 V. or 2.1 V. per cell.
These readings are all after the 'surface charge' has disipated.

[GordMay]

Originally Posted by OldManMirage

... I can't find any specs for this particular battery - Powertron P2000 6V Deep Cycle.

A website I came across said GC batts should read 6.37 when full. That doesn't seem right.

Appreciate any insight here.
Thanks !

Why doesn't 6.37 V seem right?


At 100% Charge, Trojan T-105's [for instance] specify a Specific Gravity of 1.277, and an Open Cell Voltage of 2.122 V/Cell, or 6.37 Volts per 6V Battery.
➥ https://www.trojanbattery.com/pdf/da...ata_Sheets.pdf

[OldManMirage]

So I asked the original question about voltage because if 6.37 was full why was I getting 6.5ish ? I was hoping for the "easy button" but alas, not to be !

I do get the part about load testing, and I have devised a way to do that using a trolling motor. I'll pick the most likely 2 out of the batch and try them and see what I get.

Thanks for all the responses. Helpful or otherwise...

[boatpoker]

Originally Posted by OldManMirage

So I asked the original question about voltage because if 6.37 was full why was I getting 6.5ish ? I was hoping for the "easy button" but alas, not to be !

I do get the part about load testing, and I have devised a way to do that using a trolling motor. I'll pick the most likely 2 out of the batch and try them and see what I get.

Thanks for all the responses. Helpful or otherwise...

What kind of meter do you have ? A $6.99 Harbour Freight or a $400 Fluke ?

[OldManMirage]

Originally Posted by boatpoker

What kind of meter do you have ? A $6.99 Harbour Freight or a $400 Fluke ?

Something in the middle. The meter is fine, and the meter reader has at least some clue what he is doing. He just turned 60 but still in his right mind.

[thomm225]

Originally Posted by OldManMirage

So I asked the original question about voltage because if 6.37 was full why was I getting 6.5ish ? I was hoping for the "easy button" but alas, not to be !

I do get the part about load testing, and I have devised a way to do that using a trolling motor. I'll pick the most likely 2 out of the batch and try them and see what I get.

Thanks for all the responses. Helpful or otherwise...

Maybe you are thinking how a 12 volt battery will read.(unloaded)

Like my 12 volt car battery will read around 12.5 volts if for some reason I test it.......with which ever old meter I have laying around, (this is about right for an older car 12 volt battery charged last time car was driven)

My 6 volt golf cart batteries which are in series read around 12.6 Volts (unloaded) after being off the controller/panels for a while.....like a day or two. (according to my PWM Controller with panel stowed with controllers in lazarette locker)

The internet says a 6 volt battery will read slightly over 6 volts.

Also found these which about matches my findings.

Tech Issues: What voltage should two 6V batteries have?https://www.rv.net
The two batteries in series should read 12.7 to 12.6V if there is no load and several to 24 hours after the charger has been removed. You need to be sure you ...

BATTERY TUTORIAL

While there are many battery chemistries today, and new types becoming commercially viable over time, we deal with the lead acid types, flooded, AGM, and true Gel, as they are widely used in the applications we specialize in. Lead acid battery technology has been used commercially for over a century. Some archeological finds of the appropriate materials in a man made configuration suggest the principle has been known and used much longer than that. Their construction is of lead alloy plates, and an electrolyte of sulphuric acid and water. A battery is made up of a number of cells, and the lead acid chemistry dictates a fully charged voltage of about 2.12 volts per cell. Thus, a nominal 6 volt battery has three cells with a full charge voltage of 6.3 to 6.4 volts, and a 12 volt battery has six cells, and a full charge voltage of 12.7 volts. High quality, high performance lead acid batteries may may exhibit higher cell voltage.

[Flatswing]

Perhaps the simplest answer may lie in the reason they are available. Most golf carts get 5yrs or less from a set with regular use before their capacity becomes an issue. But that’s with regular PM. Most privately owned golf carts are not watered frequently and many owners think they should be fully discharged before charging to prevent “battery memory”. (a relic from our old NiCad days). If your MIL changed them out because they weren’t lasting- well there’s your DIY load test. Use them for the core charge rebate on new ones.

[boat driver]

Originally Posted by Flatswing

Perhaps the simplest answer may lie in the reason they are available. Most golf carts get 5yrs or less from a set with regular use before their capacity becomes an issue. But that’s with regular PM. Most privately owned golf carts are not watered frequently and many owners think they should be fully discharged before charging to prevent “battery memory”. (a relic from our old NiCad days). If your MIL changed them out because they weren’t lasting- well there’s your DIY load test. Use them for the core charge rebate on new ones.

finally someone who has logical answer. how old are they? why are they being taken out of golf cart? charge them up- let stand 24 hours, test voltage-run cart two minutes-test voltage.
If not very close shot. .

[PaulCrawhorn]

Voltage means ZERO in evaluating health.

If you think they're worn out, they likely are, 3-5 years is a good run.

There's only a few good US makers

The best battery value by far is Duracell (actually Deka/East Penn) FLA deep cycle golf cart batteries, 2x6V, around $200 per 200+AH @12V pair from BatteriesPlus or Sam's Club.

NAPA relabels it here: https://www.napaonline.com/en/p/NBP8144

Deka self-labeled also sold at Lowes.

[MJH]

Originally Posted by OldManMirage

Well, I was hoping for a more definite answer based on voltage, but I get it. Basically I'm trying to decide if it's worth the effort to lug a pair down to the boat and sweat them into place. Where I have to put them it will NOT be easy!!! So I may just wait until I'm ready to fork out the dough for a new pair.

Although I am really curious. Wish I has a 12volt load sitting around the house here somewhere..hmmm...then I could test a pair and see...

I'm with Scorpius.

Call some local battery dealers to see which one would do FREE battery testing. If none of the batteries is salvageable its time to buy yourself new ones using the old ones for the core charge if they require it.

~ ~ _/) ~ ~ MJH