12.7 volts after charging, need new Batteries?

Haole Hiker · 05-25-2016, 10:12 PM

I have two 2012 Costco 6 volt Golf Cart batteries that go immediately to 12.7 volts and the within hours to 12.6 volts after coming off the charger which charges them at 13.1 volts. They remained at 12.6 volts for several days while Camping and using my LED interior lighting and Water Pump. They used to read 13.1 volts for quite some time. Should I be happy with this or should I get new Batteries? If not, at what point would you boys recommend new Batteries? Thanks.

profdant139 · 05-25-2016, 11:43 PM

I think this is normal -- my batteries do the same thing. Have you used a hydrometer to check each cell? This tool is cheap and easy to use -- not rocket science.

PieGuy · 05-26-2016, 06:15 AM

Check out Handybobsolar.wordpress.com
He is mainly talking about solar but he has some great information about batteries and charging, plus he isn't trying to sell you anything.

gmw photographics · 05-26-2016, 09:06 AM

Checking the static voltage of a battery is only one way of getting an idea of the capacity and state of charge of a battery. A better way of getting an idea of the health of the battery is to test it under load. Most auto parts houses can do a load test for you.

Haole Hiker · 05-26-2016, 08:29 PM

Thanks Boys I knew you give me some good ideas.

looking4fun · 05-27-2016, 08:44 AM

I'm assuming golf kart batteries are the same but for car and deep cycle batteries, normal volts is 12.6 volts. Charging volts is between 13.5v and 14.5 volts. After charging, your battery will read charging voltage for a little while, this is called a surface charge. Once a decent load is put on the battery the surface charge will burn off pretty quickly and should level out to 12.6. So as long as golf kart batteries are the same as deep cycles then 12.6v is normal. Also your camper dc electric is designed to run on 12.6v and a fully charged battery is 12.6v and a dead battery is considered 12v.

Haole Hiker · 05-27-2016, 09:33 AM

Thanks LFF. That confirms my suspicions and especially after reading Solar Bobs epistles. I was nervous because when I first got the Batteries (2012) they would hold that 13.1 for several days and then each year since then, after disconnecting from the on board charger and sitting for 24 hrs. it has gone down about a point. I leave the trailer plugged in all the time when home. I mostly Boondock so wanted to be sure before taking off again.

profdant139 · 05-27-2016, 11:09 AM

Haole, when you leave the batteries plugged in, are they on a BatteryMinder? I have one of those, and it seems to prolong the life of the batteries. There is a pulse function that somehow reduces the amount of sulfur that adheres to the plates, or that's what they claim, anyways.

Haole Hiker · 05-27-2016, 11:58 AM

You know I should look at that again. I replaced my Charger/Converter a couple of years ago and it's supposed to do that(pulse). I just put my vehicles that sit for a long time on those Genesis Battery Minders and they're supposed to disulfide too.

N&K · 05-27-2016, 12:28 PM

HH, your third email shines some good light on your situation. Looking4fun provided some good information. Your 6v batteries may be able to hold the surface charge a little longer so the voltage progression down goes a little slower than a 12v battery. I think the key to what you have said is that the batteries are around 4 years old. Sounds like you have taken steps, new converter/charger, to prolong the life of the batteries, but they won't last forever. If your batteries when taken off the charger go from 13.1 volts to a point lower, 12.1v, in 24 hours without a heavy load on them then they are coming to the end of their life. If they are dropping something less than that say 12.5v, then that might be normal for a 4 year old battery. Do you make a provision for charging while you are boondocking (generator or solar)? If so I wouldn't worry too much. If being out of power makes an important difference, then I'd be looking at replacing them.

Haole Hiker · 05-27-2016, 01:59 PM

Thanks N&K, I'm sorry I should have been clearer. The point lower reference was each year they seem to go down a point after resting i.e. 13.0 to 12.9 the next year to 12.8 ect. this year they go from the 13.1 volts charging to 12.7volts after 24hrs unplugged unloaded, they then stay at 12.6 for several days just using my LED's and water pump mostly, heater occasionally. I carry a little Honda 1000 just in case but delight in not using it. I love those big honkin 6volt monsters. I think I'll just take off with them and see how it goes. I guess I can always drop into a Costco along the way and trade them in on new ones. I genuinely appreciate your thoughts. HH

N&K · 05-27-2016, 02:59 PM

With your two 6v batteries, you have the set up I wish I had. I currently have dual 12v batteries. I will be curious to hear how long your batteries actually last. For now have a great time using them.

Haole Hiker · 05-27-2016, 08:41 PM

You know I used to have two 12volts in parallel but it didn't seem like I got much time out of them so I switched to two 6volts in series and I am much happier. Somewhere I read that weight in a battery means longer power and these suckers are HEAVY. Kentucky Dan I think, used two 12volts but only one at a time. Seemed smart to me since when one was used up you would know you were half way through your juice. You know the biggest juice reducer for me was switching to all LEDs. I can turn them all on at once and the Batteries barely notice.

I love my Trailer! I enjoy using it and I enjoy thinking about using it.

profdant139 · 05-27-2016, 10:55 PM

I am another user of ordinary 12 volt batteries, one at a time. I use one till it gets down to 12.2 and then switch out to the spare. Using two at once gives you more total power, but I like the safety of using one at a time.

N&K · 05-27-2016, 11:04 PM

I have two 12v mainly because I have a sleep machine that runs all night. I will get two or three nights out of a full charge. This is with led lights and just running the water pump when not hooked to shore power. Having the batteries run out in the middle of the of the night means literally a rude awakening when the power runs down. The batteries in the last trailer (tent trailer) I had lasted for seven years which was pretty good since I was recharging them every couple of nights while camping. I think that with two 6v I can get more nights between charges especially with a solar charge in the interim.

N&K · 05-28-2016, 10:18 AM

profdent, when you use your solar panel, do you charge them one at a time? How do you have the solar connected?

profdant139 · 05-28-2016, 11:34 AM

The solar clips right to the battery with alligator clips. I hook it to the battery that is in use. If we were to have a couple of cloudy days in a row (which has not yet happened, but it will when we travel to the Northwest), I would monitor my battery. When it runs down to 12.2 or so, I would swap it out with the spare.

If all else fails, I would use the generator. In eleven years of camping, we have used the generator to recharge the batteries exactly twice -- about two hours each time, in the days before we got solar. (We have used it a few other times to make microwave popcorn, but that is just a luxury, not a necessity.) I hate the sound of generators, even though we have a Honda. Noise is noise. Silence is golden.

Haole Hiker · 06-02-2016, 09:37 PM

Thanks again for everyone's help, I sure appreciate it. I have learned a lot. I bought a Battery Hydrometer off Amazon and after 24 hours resting the Batteries show fully charged. All the little balls are floating their little hearts out at the top of the tube. I found out too that the Plug in Volt meters tend to read a little low and may be somewhat unreliable. Best to got to the source (the battery water) and measure directly.

profdant139 · 06-02-2016, 10:43 PM

If you wait an hour or so after the last use of the battery, the voltage level rebounds up to its true level, and won't give you a too-low reading. (I rarely have the patience for that, though.)

qtla9111 · 06-05-2016, 08:42 PM

Dan,

Here is the chart from the famous 12V Side of Life page https://mx.images.search.yahoo.com/s...sigt=12ajf1eo0. According to the chart, 12.6 is 100% charge.

During peak full sun hours, my charger will read up to 13.9, at night we start out using lights at 12.7/12.6 and with a surge of some sort, it will drop temporarily but pick back up once that item is disconnected.

I think you are in good shape. Our batteries are five years old and I keep them watered and clean. One thing I did this last year was to change out the terminals. I had cheap terminals on the cable ends. Changing them for heavy copper terminals made all the difference.