Rv batteries

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I hate to ask this cause I know its been touched on already, I can only absorb so much info at one time though and Im learning alot about my camper thanks to you guys.

My question ( maybe again )

But first this is my situation, I plan to use the camper on the weekends only for now which means I may sleep in it Fri night if I leave work and make the 2 hr drive there that night or for sure Sat night assuming I leave my home Sat morning.

Prob thats it for now but who knows.

I have this battery in it now https://postimg.cc/PCs6CbmN with these specs. https://www.napaonline.com/en/p/NBP8240  Its a brand new battery, there is only the one.

I hate to toss it but I also want to have this camper in the woods by the end of the month ready for use and not still dickin around.

If I need to buy a golf cart battery ( or 2 )  than Ill do that but can someone tell me what SPECIFIC battery to get.

I have a 20 ft older camper, I have a new propane fridge, ( but I understand it still requires battery power )  Im waiting for my new igniter water heater,  I have a 12 volt TV which I may use a little at night ( I really dont watch TV ) and I have a new water pump Ill need to run to take a shower and give me drinking water and I have the interior light to consider. I also have to consider some nights will be cold and so furnace will be running and that has an igniter that Im assuming comes on and off.

I plan to get the solar panels from Amazon that were suggested in a different thread to re-charge. ( just not right away )

Im just looking for whats needed and nothing extra. Im not looking to live on high hog and dont have an issue with being careful with battery usage.

What specifically would you guys suggest I do? For a battery or batteries?

How can i monitor battery drain

Thanks for leading me in the direction I need to go and not suggesting I buy something that really isnt needed.

 
And not to overload but is it possible that I recharge the batteries via my truck running for a while ( and jumper cables ) on Sun morning before I  leave for the week?

How long would this take do you think? Assuming it can work that way

I plan to disconnect everything when I leave for the week so no battery drain and I can start all over again the next week
 
The big question is how do you plan to recharge the battery for now?  The single battery you have now will work, but will need to be recharged every day or two even with light use.
 
Isaac-1 said:
The big question is how do you plan to recharge the battery for now?  The single battery you have now will work, but will need to be recharged every day or two even with light use.
See second post, maybe that wont work?

I have a nice generator, I need to get that up and running again, its brand new but been sitting.

This guy https://www.youtube.com/watch?v=ZJD19RogRtg says even with golf cart batteries dont let them go below 50% discharge? Assuming thats true than how would I know where Im at? I dont have a gauge
 
That battery holds about 75 amp hours of which you can use only about 20 safely then rapid aging sets in.. Nothing wrong with it other than IT IS SMALL

A pair of GC-2.. I'd go to Sam's or Costco if you have a membership I don't so I went to DEKA

They hold around 220 amp hours and you can safely use helf of it. (110) they are designed to be discharged and recharged over and over and over again. that is about 5 times the usable power

You need two. in series (GC-2 class)

you can hook 'em in parallel with your G-24 or.. Well. keep it as a starting/jump start battery for your Tow vehicle and other cars.
 
A couple of things on charging, batteries should only be charged at a certain speed, without going into too many details right now,  as a general rule with a properly sized charger it should take about 8-10 hours to charge a battery from its 50% discharge point.  So unless you want to idle your truck all day burning fuel, charging from it on Sunday morning is not going to work.  As to that battery it is not the best type for a couple of reasons, first off that is a marine dual purpose battery, not a real deep cycle, it is a compromise design, and not really good for any one thing.  I know it says deep cycle on the side, but they lie, as such it only has about 2/3 of the capacity as well as shorter life expectancy when used in deep cycle service as the same size true deep cycle 12V battery.  The thing it has going for it is that it is bought and paid for, so you might as well use it.  Given your lack of an on site charging option, for now your best bet is probably to bring the battery home with your each week and charge it at home using a common battery charger, this can even be a small cheap $30 charger as it is ok to charger slower than the optimal rate, just not faster, though ever here you will want a 3 or 4 stage design so as to not cook the battery if you leave it hooked up too long.  Something like https://smile.amazon.com/Energizer-ENC4A-Battery-Charger-Maintainer/dp/B01GSJLD34/  Just leave the battery hooked up for a day or so until charged.  As to monitoring power, you can buy expensive monitor systems that keep track of power going in and out, or you can buy something cheap like this one https://smile.amazon.com/DROK-Programmable-Temperature-Percentage-Indicator/dp/B07759SLYP/  The cheap ones will only give you an accurate reading after the battery has been at rest for a bit, meaning no heavy loads running, so when your furnace fan is blowing this meter might show low battery even when it is fully charged, then jump back up to 3/4 charge after the fan has been off for a minute.

p.s. with the cheap meters like I linked to above you only get to know about how full the battery is, sort of like the gas gauge on a car, you don't get to know how much capacity the battery has (batteries loose capacity as they age).  Think of it sort of like a gas tank that accumulates rocks in it as it ages, the rocks take up space, and while you may know the tank was a 15 gallon tank when you bought it, you have no way of knowing how full of rocks it is a couple of years later, so full then may mean only 5 or 10 gallons.
 
You also need to know that a battery will NOT hold a charge indefinitely,,even when no load is applied.. Batteries self discharge at about 1-2 PERCENT per DAY,,,so in 30 days you have lost 50% of the charge, WITH NO LOAD! This always has to be taken into account.>>>Dan
 
If your going to camp from Saturday morning to Sunday afternoon/evening and then head home, I'd say your good either bringing a fully charged battery with you and then taking it home and recharging during the week.

OR

Get your genny up and running and when you get there, plug in and let your campers converter charge the battery by just plugging in the power cord from the camper.

Either should work and if you truly are just looking for minimalist things like you described above (Water pump for a shower, lights, water heater ignition (run it on propane and just use for ignition, Same for fridge) I think you'll be fine with the battery you have.

I had a 25' TT that I used to dry camp with and doing as you described, got two days out of the battery (same group 24 you have) before it got to 50% discharge rate. Now I didn't know then that the marine batteries were only supposed to be discharged to about 70% before recharging so I hurt the life expectancy a little but I got two years out of it. I've since switched to 12v Trojan Batteries which are very pricy but also very easy to maintain and give me enough juice to dry camp without having to run the genny everyday if I'm not running the AC. The 6v Trojans are great batteries and a bit more economical.
 
You might consider buying a spare battery, taking a freshly charged one with you each weekend.  Not hard to swap out.  Always leave Sunday with a decent battery, never know when something crops up and cancels the following weekend or two plans, and you would be happy you left it with a solid battery to start.
 
I think SpencerPJ has the right solution for you. Buy a second 12v battery and swap them on each visit, bringing the discharged one home and re-charging for the next visit.  With the usage you described, a modest Group 24 or (better) Group 27) battery should last a weekend as long as you aren't using the furnace.  Yeah, the GC2 golf car 6v's are the most capacity and longest life for the money, but that would mean buying 4 of them and swapping two each visit.  if you can get along with 80-100 Amp-Hours of capacity, and less expensive and more common Marine/RV hybrid deep cycle may be cost effective for you.


Please read the article I've written on RV Battery alternatives. It's not technically deep - just broad-brush pros and cons.  It's in the RVForum Library at http://www.rvforum.net/miscfiles/Choosing_right_battery.pdf
 
Gary RV_Wizard said:
I think SpencerPJ has the right solution for you. Buy a second 12v battery and swap them on each visit, bringing the discharged one home and re-charging for the next visit.  With the usage you described, a modest Group 24 or (better) Group 27) battery should last a weekend as long as you aren't using the furnace.  Yeah, the GC2 golf car 6v's are the most capacity and longest life for the money, but that would mean buying 4 of them and swapping two each visit.  if you can get along with 80-100 Amp-Hours of capacity, and less expensive and more common Marine/RV hybrid deep cycle may be cost effective for you.


Please read the article I've written on RV Battery alternatives. It's not technically deep - just broad-brush pros and cons.  It's in the RVForum Library at http://www.rvforum.net/miscfiles/Choosing_right_battery.pdf

I'd like to read the articles I wasn't even able to read the thing that you sent me for the water heater my computer will not open it for some reason I'm not very good at computers I don't know what's wrong but it will not open it for some reason
 
Ive tried downloading that and it gets to 90% and stops, notifies me that download failed. Thanks though
 
Isaac-1 said:
A couple of things on charging, batteries should only be charged at a certain speed, without going into too many details right now,  as a general rule with a properly sized charger it should take about 8-10 hours to charge a battery from its 50% discharge point.  So unless you want to idle your truck all day burning fuel, charging from it on Sunday morning is not going to work.  As to that battery it is not the best type for a couple of reasons, first off that is a marine dual purpose battery, not a real deep cycle, it is a compromise design, and not really good for any one thing.  I know it says deep cycle on the side, but they lie, as such it only has about 2/3 of the capacity as well as shorter life expectancy when used in deep cycle service as the same size true deep cycle 12V battery.  The thing it has going for it is that it is bought and paid for, so you might as well use it.  Given your lack of an on site charging option, for now your best bet is probably to bring the battery home with your each week and charge it at home using a common battery charger, this can even be a small cheap $30 charger as it is ok to charger slower than the optimal rate, just not faster, though ever here you will want a 3 or 4 stage design so as to not cook the battery if you leave it hooked up too long.  Something like https://smile.amazon.com/Energizer-ENC4A-Battery-Charger-Maintainer/dp/B01GSJLD34/  Just leave the battery hooked up for a day or so until charged.  As to monitoring power, you can buy expensive monitor systems that keep track of power going in and out, or you can buy something cheap like this one https://smile.amazon.com/DROK-Programmable-Temperature-Percentage-Indicator/dp/B07759SLYP/  The cheap ones will only give you an accurate reading after the battery has been at rest for a bit, meaning no heavy loads running, so when your furnace fan is blowing this meter might show low battery even when it is fully charged, then jump back up to 3/4 charge after the fan has been off for a minute.

p.s. with the cheap meters like I linked to above you only get to know about how full the battery is, sort of like the gas gauge on a car, you don't get to know how much capacity the battery has (batteries loose capacity as they age).  Think of it sort of like a gas tank that accumulates rocks in it as it ages, the rocks take up space, and while you may know the tank was a 15 gallon tank when you bought it, you have no way of knowing how full of rocks it is a couple of years later, so full then may mean only 5 or 10 gallons.

This is all new to me so often I have to read something, wait, go back and re-read at least one more time

I know some questions seem so basic maybe but for me they are not.

I thought that a camper battery could be charged via a generator back to full charge in a matter of minutes, is that true. ( without getting to far into technical jargon  that Im not gonna understand anyway )

I know I dont have my generator up and running right now but Id just like to know. Thanks
 
How long it takes to charge a battery depends on how far discharged it is, and the charge acceptance rate.  For more on this see

https://www.trojanbattery.com/tech-support/battery-maintenance/
and
https://www.solar-electric.com/learning-center/batteries-and-charging/deep-cycle-battery-faq.html

Simply put if you try to charge a battery too fast you will cook them, Trojan suggests a maximum charging rate of between 10 - 13% of the batteries 20 hour rate.  The battery you have does not specify an actual 20 hour rate, though many similar group 24 batteries are rated at around 85 amp hours at the 20 hour rate.

Therefore an appropriately sized charger would have an output of between 8.5 - 11 amps, therefore using a 8.5 amp charger, it would take 5 hours to fully charge your battery if it were discharged down to its 50% capacity.  Even this is an over-simplification as the acceptance rate of a battery decreases as it gets full.  Up to the 80% capacity levels batteries can be charged relatively quickly, though things must slow down considerably for that last 20%.  So in the real world that 50% drained battery would likely charge back up to 80% in about 3 hours, then take another 4-5 hours to reach the 100% charge point with a conventional battery charger.

Ike

p.s. it is possible to speed this up a bit, at the cost of shortening the lifespan of the battery, but even this is still talking about a matter of hours to charge a lead acid deep cycle battery like the one you own.  The above link talks about some more exotic (expensive) battery technologies some of which have MUCH faster acceptance rates, like lithium ion, which with the right charging system can be charged in well under an hour, though such batteries for RV applications are still priced in the $1,000 - $3,000 ballpark.  (here is a link to an 85 Amp Hour group 24 Lithium RV battery which is the same size as the NAPA battery you own priced at $999.99 https://www.lithiumion-batteries.com/lithium-rv-deep-cycle.php)  Of course Lithium batteries do also require special expensive chargers...
 
I can see that there is alot more to this than I thought there would be.
 
I didn't see a comment about this so I will chime in - your projected power usage appears to be very light except for one item, the furnace. Don't know what the night time temps are in your area during the time you will be using your trailer, but on a cold night that requires your furnace to be running 50+% of the time, a single, new, fully charged battery is likely to be nearly discharged by morning. Furnaces are huge power users and this is an eye opener for those who haven't experienced it. You may want to consider a catalytic heater such as the Big Buddy heater which uses no power, and much less propane that an RV forced air furnace
 
Back2PA said:
I didn't see a comment about this so I will chime in - your projected power usage appears to be very light except for one item, the furnace. Don't know what the night time temps are in your area during the time you will be using your trailer, but on a cold night that requires your furnace to be running 50+% of the time, a single, new, fully charged battery is likely to be nearly discharged by morning. Furnaces are huge power users and this is an eye opener for those who haven't experienced it. You may want to consider a catalytic heater such as the Big Buddy heater which uses no power, and much less propane that an RV forced air furnace

I see, thanks, bear with me,

Let me ask this, what do you guys do when you are camping away from a power source, Im gonna assume you run your generators?

So you run them all night? Is that true? I did not know this.

I thought that you ran your batteries mostly, ( lets say at night )  got up in the A.M, turned on your generators for a couple of hours and re-charged your batteries. Thats it

Im talking about the average shmoes like me, they guy that dosent invest 1000s in batteries.

So my options are ( assuming Im understanding )

A - run my generator ( or get the big buddy ) all night cause yes in Ocala FL I will need a furnace at night during the winter

B- Get a better pair ( as in 2 ) of batteries like the GC-2 that were mentioned and hope they will give me what I need cause yes I will be running the furnace

C- During the summer when its not too hot Im assuming I can rely on either the battery I have now or for sure the GC-2 and after the weekend over get them charged either via solar or bringing them home.

D- In the summer when its real hot I will have no choice but to again run the generator cause I will need A/C to be comftorable

Does all this sound correct?

 

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