New Golf Cart Batteries, Died quicker than anticipated...

[Diesel_Camper]

I recently upgraded from 2 12 volt marine cranking batteries to 2 6 volt golf cart batteries rated at 210AH. I was dry camping last week and it seemed like the batteries died out faster than they should have, but I'm hoping it had more to do with the temperature (about 40F) and the fact that I didn't reinstall the battery cut out switch and I powered the landing gear and slide from the house batteries while setting up...

Questions:

1. How much capacity will I loose at 40F?

2. I'm guessing the landing gear and the slide probably cost us a couple of days of battery power for our LED lighting and occasional use of the inverter for a DVD player; along with the regular loads of the frige and the LPG monitor?

[jayw900]

Clicky tips and tricks

Snip>

"For best battery life, batteries should not be discharged below 80% of their rated capacity. Proper battery sizing will help avoid excessive discharge."



Are they really suggesting to only use 20% of the battery? Isn't the normal 50% usage?

[Diesel_Camper]

T looked like 8 or 6 guage. I'd have to check it out when I get home.

[justafordguy]

That's a lot of voltage drop, what size wire is between the converter and batteries?

[Diesel_Camper]

Well I relocated the converter (had to remove the refrigerator and cut a hole in the plywood covering the space under the fridge) into the water pump cabinet directly next to the battery box. Immediate improvement in voltage to batteries. When in bulk charge I would see about 1.5-2 volts lost from the old converter location to the batteries. Now I am seeing .1 volts lost through about a foot and a half wire run. The converter immediately went into bulk charge mode and I'm keeping an eye on it now.

[Veebyes]

This is the battery I bought in 2010.Lifeline AGM 4D

6 seasons, over 700 nights use, fair amount of dry camping, no maintenance, no trickle charge during winter, still going strong & expected to do so for at least another 3 years.

[Diesel_Camper]

RangerEZ wrote:

sfpcservice wrote:
Update:

*** I discharged by batteries yesterday and then charged them via the converter overnight, much like I did before the start of our trip. I went out this morning with the hydrometer and the batteries are only showing a charged state just above dead!!!

After reading the handy bob article, I started thinking about my stock converter placement. It's towards the rear while the batteries are near the front. So my thoughts are the converter is seeing the voltage come up high enough to drop into float mode, but due to the long wire run and voltage loss the batteries never get the charge the converter thinks they have. I'm guessing we left for our trip with nearly dead batteries and whatever charge we did get was from the truck on the drive down.

My next project will be relocation of the converter within a couple feet of the battery box...

That project may be worthwhile, but maybe not necessary. Let's get some basics covered so we can better help you.

1) What kind of batteries do you have?
2) What kind of RV do you have?
3) What kind of converter is in that camper?

My Trojans took far more than overnight to get back to full charge on the camper converter. I used to give them two full days. Even out of the camper with a smart charger, it took 24-30 hours. 6 volt batteries take a while...

When you say you discharged them, what was their measured voltage at discharge?

What was the measured voltage after your overnight charge?

I have two costco GC2 batteries. I didn't measure the voltage, just a hydrometer check. The converter is a wfco 8845. It bulk charges to 14.4v and then drops to 13.6v... The problem is due to the long wire voltage drop on the bulk charge the batteries never get close to 14.4v before it kicks down. I think it would take a week to finish the charge like this. Right now I have the batteries disconnected and I'm charging them with a regular automotive charger, which shows they are low on the ammeter.

[RangerEZ]

sfpcservice wrote:
Update:

*** I discharged by batteries yesterday and then charged them via the converter overnight, much like I did before the start of our trip. I went out this morning with the hydrometer and the batteries are only showing a charged state just above dead!!!

After reading the handy bob article, I started thinking about my stock converter placement. It's towards the rear while the batteries are near the front. So my thoughts are the converter is seeing the voltage come up high enough to drop into float mode, but due to the long wire run and voltage loss the batteries never get the charge the converter thinks they have. I'm guessing we left for our trip with nearly dead batteries and whatever charge we did get was from the truck on the drive down.

My next project will be relocation of the converter within a couple feet of the battery box...

That project may be worthwhile, but maybe not necessary. Let's get some basics covered so we can better help you.

1) What kind of batteries do you have?
2) What kind of RV do you have?
3) What kind of converter is in that camper?

My Trojans took far more than overnight to get back to full charge on the camper converter. I used to give them two full days. Even out of the camper with a smart charger, it took 24-30 hours. 6 volt batteries take a while...

When you say you discharged them, what was their measured voltage at discharge?

What was the measured voltage after your overnight charge?

[Diesel_Camper]

Update:

After reading this article on RV battery charging and buying a hydrometer, I discharged by batteries yesterday and then charged them via the converter overnight, much like I did before the start of our trip. I went out this morning with the hydrometer and the batteries are only showing a charged state just above dead!!!

After reading the handy bob article, I started thinking about my stock converter placement. It's towards the rear while the batteries are near the front. So my thoughts are the converter is seeing the voltage come up high enough to drop into float mode, but due to the long wire run and voltage loss the batteries never get the charge the converter thinks they have. I'm guessing we left for our trip with nearly dead batteries and whatever charge we did get was from the truck on the drive down.

My next project will be relocation of the converter within a couple feet of the battery box...

[RangerEZ]

I have the same question as Starcraft--what are your expectations and how quickly did they die? As the others have said, don't give up yet. Once they get used and cycled a few more times, your battery life will be better.

I am a fan of the two 6v option myself. I made the switch to two Trojan T105 Plus 6v batts for my last trailer and with the occasional generator use--while powering the coffee pot in the mornings and topping off in the evening for example--I never came close to running out of battery power even on extended boondocking trips. For my new fiver, I will be installing two U.S. Battery US 2200 XC2 6 volters rated at 232ah each. I expect this will be a very good solution and a very good bang for the buck at $250 plus some cables.

[laknox]

Dunno, but my 2 6v golf cart batteries consistently give 1 more day boondocking than my 2 12v batteries did before I switched.

Lyle

[DownTheAvenue]

Happy Prospector wrote:

DownTheAvenue wrote:

And therein lies your problem. With 12 volt batteries, you double your amp hours when connecting two batteries. With 6 volt batteries, the amp hours of both batteries remains constant while the volts double.

So, if you had two 210AH 12 volt batteries, you had 410 AH of juice. With the two 210AH 6 volt batteries, you had 210AH of juice.

IMHO, 12 volt batteries are always a better choice.

A 210 AH 12 Volt Battery? That's one big battery.

I do believe Downtheavenue may be Educated Beyond His Intelligence.

It was an example demonstrating a law of electricity using simple math!!!!!!!!!!!!!!!!!!!!!!

Sorry you did not understand.

[DownTheAvenue]

okan-star wrote:

DownTheAvenue wrote:

sfpcservice wrote:
I recently upgraded from 2 12 volt marine cranking batteries to 2 6 volt golf cart batteries rated at 210AH.

And therein lies your problem. With 12 volt batteries, you double your amp hours when connecting two batteries. With 6 volt batteries, the amp hours of both batteries remains constant while the volts double.

So, if you had two 210AH 12 volt batteries, you had 410 AH of juice. With the two 210AH 6 volt batteries, you had 210AH of juice.

IMHO, 12 volt batteries are always a better choice.

Have to disagree with thatlook here

You can disagree all you want, but what I said is a fact. Two 6 volt batteries wired to yield 12 volts will keep the amp hours of the batteries the same. Two 12 volt batteries wired to yield 12 volts will double the amp hurs.

THAT IS A FACT AND A LAW OF ELECTRICITY.

[starcraft69]

How long did they last????? What are your expectation? If you were hoping for several days with a heater running?????

[12thgenusa]

Golden_HVAC wrote:
. . .The load is 0.8 amps per hour. . .furnace is an additional 6 amps each hour. . .old lights add 1 amp per hour. . .new LED's are only about 0.2 amps per hour

I know what you thought you said, but there is no such measurement as amps per hour.

Many modern RVs might have a phantom consumption more on the order of 7 to 10 amp hours per a 24 hour period.