RV goers who spend a lot of time in remote locations without any electrical hookups may find themselves needing to replace their RV batteries more often than those who regularly connect to outside power sources.
The RV batteries are what run the standard amenities inside the unit, including lights, radio, and refrigerator. There are even some things inside the RV that most travelers do not think of that require a battery source, including CO2 detectors and the water heater. All these items can add to the quick drain of older batteries. If you know you will be doing a lot of boon docking, it might be best to replace your current batteries with a higher-quality and more reliable battery.
Related video: Simple RV Battery Maintenance To Keep Them Going Longer
Choosing the right battery for your travel needs will help ensure you have all the power you need, even while out in the middle of nowhere.
Types of RV batteries
There are a variety of different RV batteries available. Finding the best one for your unit will depend on the size of the unit, appliances inside, and the type of RV travel you will be doing. Select a deep cycle battery, which is designed to supply power for extended periods of time. They are built to be drained (almost all the way) and then recharged hundreds of time before it reaches the end of its life cycle. Deep cycle batteries are available in various capacities, including 12-volt and 6-volt. The 6-volt will help keep some appliances running, however 12-volt power is necessary to start up some of your RV’s systems.
There are other types of batteries available for your RV, including flooded acid, gel cell, and AGM batteries. Flooded acid batteries are cheaper and can be used in your RV. However, these take a little bit more maintenance than standard deep cell power batteries. Gel cell batteries are another option for RVs, however they are very finicky and more expensive. Both flooded acid and gel cell batteries need to be in a well ventilated area due to the gases produced while being used.
Many RV experts suggest using AGM batteries, mostly because there is no gassing and can be placed in a non-ventilated and confined space. AGM batteries are designed for rugged trips and best suited for various conditions, including the high vibrations caused by driving around.
When planning extended road trips, especially ones where you will not be connecting to outside power sources, it is best to upgrade and replace your batteries. It is also a good idea to check all batteries for power levels and hours used. This will ensure you have the highest-quality power source while boon docking.
house batteries won’t charge while plugged into 50amp shore power, they do charge when plugged into 30amp shore power or with generator running.
My leveling units are going very slow and despite keeping battery maintenance up I think they need to be replaced. I currently have 2 ROADHAWK heavy duty 12 volt deep cycle vented batteries. What other brands might be suggested or should I stay with this brand/type?
Optima is my favorite for best battery. They hold up great but do cost a lot more. For a standard deep cycle I prefer Crown, they are a great choice too. I would stay away from store brands unless they are marked “gold” as these are made to hold up longer than standard. Most standard batteries are made the same so even between brands there aren’t much differences but I will cay that Crown uses thicker plates and they tend to hold up better.
I bought a single DB 100 AH battery 12 v about a month or so ago. I am at the point of installing the battery. I am replacing 2 6V batteries with the DB battery. I bought the 20A DB charger as well. My rig is a 2004 Monico La Palma.
I would like to know if I can install the battery, and replace the current RV converter, an Inteli Power 9100 PD9160A with the DK 20A charger. I don’t think I can leave the charger hooked and plugged into shore power. The instruction says to not leave the charger connected longer that about 20 hours at a time. Can I then plug in the RV with the DB battery and the DB charger between trips, and leave it connected? Probably not.
Can the DB charger be active to charge the batteries, then disconnect from shore power after the 20 hours, or can it stay plugged in? In other words, should I charge for 20 hours, then disconnect until 24 hours before the next trip, then plug in again to shore power? Should the converter be disconnected from the battery?
Will the engine battery be effected if I leave it unplugged, or the converter mot charging the house batteries? I am also trying to contact Monico Coach technicians, but is very difficult.
Can I put a switch to deactivate the charger, after the 20 hours?
I am confused at this point and would appreciate a reply to my email, on file with my account info, or a call to my phone number.
Hi Paul. You don’t want to replace the converter with this charger. The converter provides much more amps to the system compared to a charger. The converter powers the whole 12v system and charges the battery when plugged into shore power. The charger you want to install is just to charge the batteries only. These are two different systems. If you want to use your charger instead of the converter when plugged into shore power to charge the batteries, you will need to isolate the battery from the RV system. I only recommend this when the RV is not in use as the battery helps the converter when higher amp draws are required. You would want to install a disconnect switch and then has the charger connected to the batteries if this is what you want. When you want to use the camper, you will just need to turn the switch on. The engine battery typically only charges when the engine is running so this charger shouldn’t effect it.
Dan
RV Repair Club
When I have electric power to the RV and the inverter is on my battery to the vehicle engine will not start, I checked power to that battery and it showed to be 5 volts, I hook up my charger on quick start for about 5 to 8 minutes and the engine start so where have I been messing up
Hello,
Great question! The ‘Ask an Expert’ section is currently for members of our online community. By becoming a member, you will have access to our expert’s knowledge. With your membership you will also receive discounts on products and hours of Premium video content.
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I’m a new RVer and my rig has a solar panel and will be parked outside but covered by a sail cloth awning during the winter in Texas. I will probably use my camper 1-3 weekends a month even then. Based upon your classes for batteries, do I still need to be using a battery minder even though I will be plugged up to electricity when not being used?
Hi Tom. You don’t have to. The converter in the unit acts as a trickle charger when plugged in and the battery gets charged. The brand Minders have more options and can help batteries last longer but the built in converter will keep your batteries charged while plugged in.
Dan
RV Repair Club
The SL178 12V 78 FLOODED 24 battery with side posts is recommended for my 2007 Chevy Thor 4 winds RV.
1) What is a compatible replacement with top posts? The side posts do not have enough threads to securely hold the cables.
2) Does this have to be a deep cycle battery to start the RV engine?
Hello. You don’t want to use deep cycle for a starting battery. These have weaker plates and aren’t strong enough and won’t last long. You have to get a starting battery for the engine. It is best to measure the location of the battery and see what local stores have that would fit and have proper terminal locations.
Dan
RV Repair Club
I pulled two old 6 V batteries and installed two brand new Deka deep cycle 6 V batteries. I reconnected the cables exactly as they were on the old batteries so that the 6 V batteries generate 12V together. After I installed the new batteries, the electrical system does not work. I have looked around my 2004 trailer, but it does not have a battery disconnect switch, at least not that I could find. I looked for a battery disconnect switch where the batteries are mounted on the towing hitch, in the front of the trailer. The GFCI switch in the kitchen does not operate, so the batteries are not sending electric power to the trailer. I cannot figure out why they are not sending power to the trailer, because I hook them up exactly like the previous old batteries were connected. I do have a battery minder maintenance charger and the green light is on so those wires are connected successfully to the new batteries. The battery minder wires are blue for negative just like the RV negative wire and red for positive just like the RV positive wire.
Hi William!
The batteries only power the 12v and not the 120v. The GFCI outlet is part of the 120v system and will only operate when plugged into shore power through and electrical outlet. The batteries will only power the fuse panel inside which then powers the 12v circuits for items like lights, furnace, water pump, slide outs, radio and vent fans. The AC, outlets, microwave need to have power from being plugged into an outlet. If there is nothing working in the trailer then you will need to trace the battery wires to see where the voltage is lost. Often there is a circuit protector near the batteries like a fuse. Make sure to check around the front for a fuse and also at the main power distribution center. You also need to check the battery ground connection. The negative wire from the battery will connect to the metal framing at some point. This connection needs to be good or it will prevent the batteries from sending voltage back. Most of the time this comes down to a loose connection somewhere. Tracing the wiring and testing the voltage is the best way of tracking down the issue.
Sincerely, Dan RV Repair Club Technical Expert
level system resivour
Hello Francis!
We’d love to help! Could I have a bit more information as to what you’d like to know about the level system reservoir? Also, we would need the year, make, and model of your RV.
Thank you!
Jessica
RV Repair Club Video Membership
nEED cONNECTION SCHEMATIic FOR BATTERY CONNECTION
Hello John!
We’d love to help!
Could I get a bit more information regarding your batteries? Could we get the year, make, and model of your RV?
Thank you!
Jessica
RV Repair Club Video Membership
I will be mostly boondocking soon. Will a solar panel recharge my batteries enough so I don’t have to go in and find and probably pay for the use of an electrical outlet? I run the very basic things while camping. Thank you
I’m a Navy vet and recently had knee surgery so my routine of a weekly start up was delayed for 6 weeks while I was recovering and apparently the 2 chassis batteries that start both the genny and RV both “died” tho I’ve plugged into 50 amp AC. Took a jump and was able to start the RV and let it run for 45 minutes and couldn’t restart it after shutting it off. I’m not working right now as I’m undergoing physical therapy so is there are economical batteries I can buy to resolve my issue?
Joey,
Yeah it does sound like the batteries are not holding a charge. There are many different brands of batteries that are cheap but hold up well. Everstart, found at Walmart, are very affordable and work well but don’t expect them to last more than 3-5 years. Duralast is another brand that is a good choice and they have different levels of grade based on what you want but are dependable, can be found at Autozone. Every auto parts store has their own brand and they are all very similar but I have used these two brands many times over the years and have had good experiences with them.
Sincerely,
Dan
RV Repair Club Technical Expert
How and where do I check the solar system on my unit without taking the panel off on the roof?
Dear Rob,
We’d love to assist you! Would you be able to provide the year and make of your RV so we can assist you further! Any details you can provide is appreciated!
Sincerely,
Jessica
RV Repair Club Video Membership
what about 50 or 100 AH LITHIUM batteries. and how many? any particular brand? what is the best for boon docking for an extended period of time ? i have a generator, but, don’t want to use tons of propane. thanks….
Dear Stuart,
We’d love to assist you! Would you be able to provide the year and make of your RV so we can assist you further! Any details you can provide is appreciated!
Sincerely,
Jessica
RV Repair Club Video Membership
my onan generator will not start or run. the last time I used it last year it started and ran perfect. what should I check first
I have two 12volt coach batteries; can I add 2 additional coach batteries (6volt each) to get longer lasting coach battery power when boondocking. If so, is an additional inverter required for the new batteries? Thank you, Jon
Hi Jon,
Yes you sure can do that and no other item or inverter is needed. When 12v batteries are connected together they are in “parallel”, positive to positive and negative to negative. When 6v batteries are connected in the system they need to be connected in “series”, positive of first battery to negative of second battery. These systems can be tied together. Just make sure the second 12v battery is parallel to the other 12v battery and the same to the load (camper)
I hope this helps!
Dan
RV Repair Club Video Membership
Does anyone know what fuse the map lights are at I also have no idea where the battery disconnect switch is
Hello,
I would like to help you track down the battery disconnect and what fuses to check but I would need the year, make and model of your RV. If you have access to the owners manual, there should be information on where to locate the fuse panel and where they may have installed a disconnect. If you can’t find them, please provide the info and I will help you out.
Thanks,
Dan
RV Repair Club Video Membership
Enjoying the RV Repair Club videos and, as a newbie, am learning a lot.
Where could I buy a nice solar system for boondocking sometime
I have had an issue with dead batteries and just had them replaced under warranty. I have been told to keep the battery disconnect turned on when not using my unit. The lights still work when in disconnect on position and don’t when in disconnect off position at which time the switch key can be removed. Which is correct as I get a different answer from each tech at the dealer. Also should the inverter for the 3 door residential be turned on when connected to 50amp shore power??????
What is the best battery for me.
Hello,
Can you please provide us with the year make and model of your RV and we can look further into your question for you?
Thanks,
Becky
RV Repair Club Video Membership
My living room slide, driver’s side will not come in on the front end. I have checked the gear and all “teeth” are intact. May be slipping a little, hard to tell. Anyway, I always level up before putting slides in or out. This one seems to have issues pretty often. The gear was recently replaced. Some of the teeth are shiny, like they have had some sort of bind. Any ideas?
Hi Lisa,
To provide more specific troubleshooting information on your slide room we need the make, model, and year of your rig. If it has a gear system like you indicated it could be either a Lippert Components Inc (LCI) hydraulic system, or Power Gear. Some of the older Power Gear models had individual motors for each ram or gear. If it’s a hydraulic system, I would start by checking the fluid level in the reservoir and then power to individual motors.
Hope this helps,
David
RV Repair Club Video Membership
How fast will it drain power
Hello,
I assume you are referring to how fast will your house batteries drain, or more important; How long will they supply power? There are a number of factors that will affect how long the batteries will provide power starting with the size and number of batteries. Batteries are label in amp hours or groups such as group 24, 27, 31 and higher. A group 24 battery is the lowest amp hours with 80-100 amp hours and will not last very long. Then you have to factor in the number of batteries. The more you add, the more amp hours. 6-volt battery systems require two batteries connected in series (negative to positive) which creates one 12-volt battery bank, but does not increase the amp hours. So two 6-volt group 24 batteries will only provide about 100 amp hours while two 12-volt batteries connect parallel (positive to positive, negative to negative) will create a 12-volt bank, but twice the amp hours or 200. To increase the amp hours on a 6-volt system you would need to add two more batteries connected in series and then connected to the first bank parallel.
Then you have to factor in the condition of the batteries. As batteries draw down, sulfation coats the plates and can weaken the batteries or decrease their energy storage capacity and must be recharged with a multi-stage charger to break up the sulfation. This can only be done with an inverter that has this feature, or a converter with such as the Charge Wizard featured in Progressive Dynamics converters. Most RV batteries have lost 25-30% energy storage capacity after the first year! Next, factor in what your energy usage is, in other words, what appliances, lights, and other 12-volt items are running and how often. Some appliances like the heater run on LP but use a large amount of 12-volt power for the fan. Same with interior lights, especially the older halogens and makeup lights. Limit your draw by replacing them with LED lights.
As you can see, there are so many contributing factors on the condition/size of the batteries and the amount of items being used to have a generic length of time for all RVers. You should be able to calculate your usage and battery size to determine what you “should” be getting for time, however knowing the condition of the battery sulfation is impossible without fully charging the batteries and connecting them to a 25 amp draw machine.
Thanks,
David
RV Repair Club Video Membership
I have two questions:
1- After wiring “repairs” under the dash by my local dealer (who I don’t recommend, by the way), my auto levelers will not work for about 15 minutes after I stop. The panel says “Ignition On” even though the keys are in my hand. after about 15 minutes, they work fine. In addition, there is now a constant draw. If I park and leave nothing on (I get that things still run in the background) with a brand new battery, the next morning it is 2/3 discharged. The second day, it is dead. However, we cannot figure out where the draw is coming from.
2- I admit I don’t understand the whole inverter/converter issue, but when I am on battery power, I can watch TV, run lights, etc… but I cannot plug my phone or laptop into a plug and charge them. How does the inverter run the TV but not the plugs? That is what I cannot get my head around!
Hi James,
Question #1, check out the video on finding a parasitic drain on the site. Disconnect the negative cable to the house battery and use a multimeter on 12-volt setting and apply one probe to the cable, the other to the empty post. You can also use a simple 12-volt test light. Have someone pull 12-volt fuses at the distribution center until the light goes off or it reads no voltage draw.
Question #2
There are several types of inverter brands and power available. The inverter takes 12-volt power from the house batteries and supplies 120-volt power to various appliances or circuits depending on the size of the inverter and how much battery power you have available. Small inverters (100 w) will only run a TV/DVD set up while larger (2000w) models can run the refrigerator with a large battery bank. So when you are on battery power, your inverter will supply 120-volt power to the TV, however your interior lights are powered by the 12-volt house batteries, not 120-volt so the inverter is not connected to them so the outlets would not work. The outlets in your rig are 120-volt power and most inverters do not connect to them as there is a microwave and other high impact appliances that would require to much power! Question #1, check out the video on finding a parasitic drain on the site. Disconnect the negative cable to the house battery and use a multimeter on 12-volt setting and apply one probe to the cable, the other to the empty post. You can also use a simple 12-volt test light. Have someone pull 12-volt fuses at the distribution center until the light goes off or it reads no voltage draw.
Question #2
There are several types of inverter brands and power available. The inverter takes 12-volt power from the house batteries and supplies 120-volt power to various appliances or circuits depending on the size of the inverter and how much battery power you have available. Small inverters (100 w) will only run a TV/DVD set up while larger (2000w) models can run the refrigerator with a large battery bank. So when you are on battery power, your inverter will supply 120-volt power to the TV, however your interior lights are powered by the 12-volt house batteries, not 120-volt so the inverter is not connected to them so the outlets would not work. The outlets in your rig are 120-volt power and most inverters do not connect to them as there is a microwave and other high impact appliances that would require to much power!
Hope this helps,
David
RV Repair Club Video Membership
Great article (reminder) about how the silver cable that we attach to our tow vehicle during each hookup is connected to a switch capable of killing all power to our unit. Great to know/will keep in mind/Thanks for sharing!
I just bought this unit and I plugged it into the house, it has a 30 amp plug, I have power to the trailer but none to the fridge, I think it runs on ac,lp,or 12nolt…I do no thave lp hooked up to it yet when I turn the power on the green on light comes on but I hear nothing, then about 10 seconds go by the lp and the on light and lp light start blinking together about every second help please
Slide out problem
What is your recommended brand of battery …LifeLine, Magna Power, Exide, ETC.
Hi Walter,
There are several good batteries on the market such as Trojan, Lifeline, Optima, US Battery, and even Napa which is being used by Winnebago. I would recommend any of the name brand models, but not discount brands found at home improvement stores or implements that state they are RV/Marine. More important is to maintain them and properly charge them with a multistage charge to reduce sulfation.
Hope this helps,
David RV Repair Club Video Membership
What’s the battery size
house battery will charge with generator on or when hooked to shore power,,,BUT not when engine running, ??what up
What are the best coach batteries
Hello John,
It all depends on how much dry camping you do and the amount of amp draw you have. Lead acid batteries are very common in the RV industry, however they do need more maintenance than Absorbed Glass Mat (AGM) batteries. Lead acid require a multistage charge every month which is a high voltage bulk stage (16-volts) that breaks up the sulfation and then goes into a float and equalizing stage. If you do not have a large inverter with this function or a converter with a desulfation feature, they become sulfated and lose storage capacity quickly. Lead acid batteries typically last 2-3 years for the average RVer due to sulfation when they should last 5-7. Another consideration is 12-volt vs 6-volt. A 6-volt system requires 2 batteries connected in series which is positive to negative and gives you 12-volts. A 12-volt system can power a rig with only 1 battery. When connecting 2 6-volt batteries in series, you do not double the amp hours or storage capacity, just the voltage. When connecting 2 12-volt batteries parallel which is positive to positive, negative to negative, you double the amp hours. The advantage of 6-volt batteries is they have more plates and will drain and recharge more often which is called cycling so they last more years if conditioned properly. If you are looking for a battery that will power more things longer, then you look for the group rating or amp hours. A group 24 will only have 85-125 amp hours and typically will not last more than one day. Group 27 is much higher and so is group 24. Going to an AGM battery means less sulfation, but is still rated in the same amp hours as the groups. Then you have to factor in brand! Trojan has been a trusted source for years, however Winnebago Ind did extensive research and found the NAPA brand batteries had thicker plates, better welds, and overall lasted longer? I would stick with Trojan, US Battery, or Napa and stay away from cut rate batteries as you get what you pay for. If you are looking at AGM batteries I would recommend Lifeline, Optima, Trojan, and US Battery.
Thanks,
David
RV Repair Club Video Membership
I want to connect my battery to a solar panel , we are going to dry camp for about 4 days and I want to keep my batteries full if possible, I have a 15 amp panel.
Should my lights work in RV when plugged in to shore power and house battery in in storage ?
Hi William. It depends on the make and model you have. Some run the positive and negative through the batteries to the converter and removing the battery creates an open circuit which does not allow the converter to provide 12-volt power to the interior components. Most use a separate circuit that will power the smaller items like lights and roof vents, but not slide room motors or leveling jacks.
Thanks
Dave-RVRC
I hooked up a back up camara to the running lights on my rig and after turning it on for the third time the camara and all my running lights went out. I checked the fuses up front and they all look good. Any suggestions on what to do?
Hello William,
To provide more specific information regarding your back up camera and running lights issue we need the make, model, and year of your rig. I would start by checking voltage to the camera and the lights? You may have a wire that disconnected? If this is a trailer, check to make sure you don’t have a separate set of fuses for the trailer wiring? If it’s a motorized, then there must be a second set of fuses for the running lights somewhere you have not seen?
Thanks,
David RVRC Video Membership
I have two AGM house batteries that are approximately four years old. They are completely drained while driving after 6-7 hours. The batteries are so low that I cannot even start the generator.
I believe the isolator relay is failing as I get intermittent charging of the house battery from the alternator – need to know the part number in order to replace it. Can you find that based on the RV model? I don’t want to open up the driver’s seat until I have the replacement part in had to install. Thanks – first time I’ve tapped you with a question.
Hello Paul,
To provide more specific information on the PN for the isolator you are
referring to we need the make, model, and year of your RV. Are you
referring to the battery disconnect/relay? If so, it could be
similar to the BIM Battery Isolator that Winnebago has used for
years.
Thanks,
David RVRC Video Membership
If I use a battery minder, and connect to engine battery will it also charge the house battery?
Hello William,
No, the house batteries will only be charged if you have a battery
solenoid that provides a charge from the engine alternator via the battery
when the engine is running. It creates an “open” circuit when not
running meaning no continuity to the house batteries.
Thanks,
David RVRC Video Membership
Is it feasible to obtain more battery life by hooking 2~6v batt’s to my 2~ 1yr. old 12~v batt’s on my trailer??
Hello Arthur,
It depends on what “battery life” you are referring to? If you are
looking for longer battery life meaning years of service, no. If you
are referring to longer amp hours to run things before the battery goes
dead, possibly, however if your existing batteries are sulfated and are
running at 50% or less of capacity, they will drain the new batteries down
and provide only a small increase in amp hours. Two 6-volt batteries
need to be connected in series meaning positive to negative which creates
a 12-volt battery bank. This does not double the amp hours for each
battery, just the voltage. So if you have a group 24 6-volt battery
you will only have the 80-100 amp hours of a single 12-volt group 24
battery. The advantage of a 6-volt battery series is they last
longer due to more plates and more cycling times. I would suggest
getting another 12-volt battery and adding a battery minder that will
condition the batteries and provide optimum efficiency meaning they will
hold the charge intended and not lose storage capacity due to
sulfation.
Thanks
David RVRC Video Membership
What’s the best battery system for me to use – I do also use a generator.
Hello Michel,
To provide more specific information on the best battery system we need the make, model, and year of your rig and how much dry camping you are planning to do. If you will be parked and connected to an electrical source, you will not need much battery storage as your converter will provide power to the batteries. If you are dry camping, then you will want a larger bank of batteries for more amp hours. There are basically 2 types of batteries used for the house (deep cycle) batteries, lead acid and absorbed glass mat (AGM). A big misconception in the industry is the AGM batteries provide more power, they do not. Both are available in group 24, group 27, group 31 and up, all of which refer to the amp hours available. AGM batteries require less maintenance and therefor have less sulfation which in time will reduce the batteries ability to store power. Lead acid batteries require a multi-stage charge once a month and most converters do not provide this charge.
Thanks,
David RVRC Video Membership
Generator won’t start clicking noise when pressing start .
I am new to raving. My lithium ion batteries tend shutdown overnight. We are not plugged in. When we press the reset everything comes back on and the battery is not drained. Is there something I’m doing wrong?
I have the battery that runs the van via gasoline. I have an alternator that converts the energy generated by the engine to 12V energy, sending said energy to this secondary (yellow) battery. But I don’t know when to plug in to my house to store additional energy for a trip. I don’t know how I should hook up various plugs when I’m just driving around town, when on a trip, etc. The van has a fridge, microwave, air conditioning, tv/DVDs player, etc. So the process shouldn’t be too difficult. I just can’t find information at this very beginner level. Can you help?
When plugged in to shoreline does the bat. disconnect need to be switched on in order to charge the batteries?
Typically the battery disconnect needs to be on for the converter to provide a charge to the batteries as it is an inline solenoid. Having said that, I’ve learned to never say “always” when it comes to how manufacturers build and engineer so I would recommend testing the charge with a multi-meter to verify. Set your meter to 12-volt DC and with the unit not plugged in, test the battery or batteries with the disconnect off and you should see 12.5 volts if they are charged. Plug the unit in to a 30-amp source, wait about 1 minute and check the batteries again. If it is charging, you should see about 14 volts at the batteries. We do have a video on the site showing how to check the charge in the electrical segment, however it does not cover the disconnect switch.
House batteries are too weak to start generator. I have a shore charger(110) but hopefully i can place the positive lead to the correct house battery. I have four.
Suggestions would be welcome.
Ty, ron
My house bank of batteries is comprised of four 6 volt batteries. Is it possible to go to two 12 volts? Why would they use the 6 volts instead of 12 volt? I may need to replace some of my 6 volt batteries
This has been a long standing argument between different RV manufacturers for years. It has also been a source of confusion and misinformation as well. There is a lot of talk about how the 6-volt batteries have more power and last longer. This is only half true, two 6-volt batteries connected in series (positive to negative) give you a 12-volt system but do not double the Amp Hours like many people think! If you have a group 27 battery, you will have the same Amp Hours in two 6-volt batteries as you have in one 12-volt battery! But you have to pay double for the 6-volt? Your system with four 6-volt batteries has no more Amp Hours than a rig with two 12-volt batteries at the same group rating. The advantage is the 6-volt batteries should last longer if properly stored and charged meaning you will get more “cylces” or recharges. The biggest problem with lead acid batteries in the RV industry is sulfation which occurs when the batteries are allowed to sit in a discharged stage for a period of time or are not conditioned properly. Lead acid batteries need to be charge once a month with a multi-stage charge which starts with a high voltage bulk charge that boils the acid and breaks up the sulfation, then it goes into a float and equalization stage. Just leaving it plugged in to a typical converter does not provide the proper charge, and leaving it sit in storage enhances the sulfation. The only rigs that have proper charging conditions are the ones with a large inverter such as the Freedom 2000 which does have a mulit-stage charge. Even charging them in your garage during storage is probably not a multi-stage charge as these chargers are very expensive!
So you can replace your batteries with the 12-volt deep cycle battery, however before you do that I would recommend visiting the site and reviewing the videos and blogs on battery maintenance and conditioning. Also, I would recommend getting a Battery Minder at Northern Tool which conditions batteries by sending in high impact waves to break up the sulfation and they claim to extend the life of batteries by 200 cycles. That could be 2-3 years! I have been using them for about 5 years on almost every type of battery available in RVs, dump trucks, skid loaders and I am a big fan! No gassing, loss of acid, and the batteries last. Take a look at Northern Tool as they seem to have specials on the various sizes that can not be found anywhere.
Hi – I am searching your videos and cant find one on checking the battery charging system in the trailer. Is is connected to the fuse panel system?
Hi, Bill. Checking your battery charge status in a trailer is the same as a motorhome which we do have video on? Check out the video showing how to use a multimeter to check the charge coming in here: https://www.rvrepairclub.com/video/rv-battery-maintenance-checking-battery-charge-007937/
Using a multimeter set on the 12-volt DC voltage setting, you can put the positive (+) lead on the positive battery post and negative (-) lead on the negative post and get a current battery voltage reading. Plug the unit in and you will see the charge coming to the batteries. Also, you can unplug the shoreline power, plug in your tow vehicle and if you have a 7 pin connection, you will see a charge coming from the engine alternator as well.
IN PROCESS OF LEARNING BEST & MOST EFFICIENT (INEXPENSIVE) METHOD FOR DOING SOLAR PANELS ON MY TRAILER
motor lost all battery power
lost all power to moter
Does an inverter on and RV act as a battery maintainer or is it just a battery charger. When sitting idle during the winter months, should you disconnect the battery switch or let the inverter do the work keeping the battery maintained.
It depends on what type of inverter you have AND if you are connected to shoreline power or solar panels? An inverter is designed to take 12-volt battery power and “invert” it to 120-volt to run items like the TV, refrigerator on electricity, and other items. The larger inverters also have built in converters which are basically battery chargers but they need to be plugged in to an electrical source to charge the batteries. Check to see if your inverter has a multi-stage charger and make sure it’s plugged in, otherwise your batteries will go dead and sulfate.
I have read what you said about batteries, but I am still confused. We only use our trailer once a year, and it is on shore power at that time for about a week. We do open the slide outs using the battery a few times a month to clean and inspect. When it is plugged into shore power, is it charging the battery during that time, and is that enough to keep it charged for a whole year? Should we plug it in more often, or should it periodically be on a battery minder? We have had this trailer for five years and the battery still opens the slide-outs. We are not handy with these things and we just assumed that we didn’t have to do anything to keep the battery working….just plug it in once a year. Thank you.
Just plugging the unit in for one week will not “condition” the batteries, rather just keep them topped off and leaving it sit the rest of the year will drain them and cause sulfation which means they can store less energy. Since you are only using the unit for one week and keeping it plugged in, the batteries probably have enough storage to last the week being plugged in, however I would bet if you tried dry camping, you would be without power in less than one day. I would suggest connecting a battery minder and leave it on when in storage, or maybe get the solar panel version and just let it condition, it will extend the life of your batteries for a long time.
I enjoy your presentations. I wonder why I am asked to pay for something I pay yearly for? My refrigerator stops after a few days. I up the temperature, and then it works again. What does this mean.
Hi, Helen. No additional payment would be required to view the Premium content, as long as you are logged into your Premium Membership account. Please contact us at 1-855-706-3536 if you still experience issues with this.
Typically if your refrigerator stops working and then starts again after you raise the temperature, your monitor panel is getting false readings typically from the thermistor. Depending on your model and year, the thermistor is clipped to the fins inside the regular refrigerator compartment and sends the temperature to the monitor panel which starts and stops the cooling process. Several things could cause a faulty reading such as poor air circulation which causes warm air to rise and create a pocket at the top which would send warmer temps and typically cause to much cooling and ice forming which is not your situation. The thermistor can get covered in ice and it would sense the cold temperature and tell the monitor panel that the temp is ok so it won’t start until you raise the temperature. The thermistor could be too far down on the fins again sensing a cooler temperature? Or the thermistor is getting weak? First, locate the thermistor and make sure it is not covered in ice. Next, remove it and place in a cup of ice water for about 5 minutes. Get a multimeter and check the ohm resistance to see if it’s within the manufacturer’s specification. There is a video on this in the appliance section. Check your owner’s manual for the proper reading. If you can not find it, provide the make, model, and year of your refrigerator and we will get one for you. I would bet your thermistor is starting to get weak and needs to be replaced.
I am trying to FIND my ‘house battery’. It’s not under the hood, nor under the fridge. Not under the passenger seat, nor in the bathroom. Not in the doghouse…… where is it?
Hi, Kathy. Please see your email for a response from our expert!
I’ve learned over the past 34 years in the RV industry to never say NEVER! However I do believe your rig has a house battery somewhere as the engine battery is a cold cranking start battery that can not withstand the discharge and recharge required for lights and other components. Typically the engine battery is located under the hood in the engine compartment and the house battery can be almost anywhere. It needs to be vented due to gassing while charging so the compartment or location needs to have an access to the outside. I have seen some models located under the driver’s seat with an open vent under the chassis, some inside a side compartment, and others in a step well.You should have a distribution center with circuit breakers for the 120-volt appliance. This also has a converter to charge the house battery. You should be able to find the red and black 12-volt wire and follow it to the battery.
inverter went bad 55 watt. what is a good replacement for my camper?
Hi, Bill. I believe you might have incorrect specs? The smallest inverter typically used in an RV is a 135 watt model that will just run a 20” TV? Some inverters such as the Progressive Dynamics 125 watt models can be rebuilt by the factory! If you can provide the make and model, we should be able to match up a replacement or find out if yours can be repaired. Also, make sure you are not referring to the converter which only charges your batteries?
Why no mention of 6 volt batteries in series which is the best option with golf cart batteries outlastIing any deep cycle 12 volt batteries.
We don’t the generators in RV’s have an emergency manual pull starter? We have had both chassis and house batteries go dead and had to get jump start. A pull starter generator would have saved the day. That should be standard on any RV with a generator.
Hi, Steve. I have referred your question to my technical contact at Onan and he indicated it was a space and compartment logistics issue. To be able to pull start a 3000-5000 kw generator you need a very large winding housing and amble space for an RV owner to actually pull the cord. Then, if the cord breaks, it’s an expensive repair to drop or remove the entire generator to replace a cord. And his final comment was, it wouldn’t sell! Guess they would sell at least one? If you have experienced dead batteries on both the house and engine side I would investigate the culprit of the drain immediately. Plus, I always bring along a portable emergency battery pack when I hit the road. I can hook this direct to the leads on the genset and jump start it if needed!
I have 2 six volt batteries wired together with the connection between at the + of one to the – other. What should a multimeter read end to end.
Hi, Gray. Your 6-volt batteries are connected in “Series” meaning positive (+) to negative (-) which creates a 12-volt system. When you connect a multi-meter it should read 12.5 volts at full charge. A 12-volt system is connected parrallel, which means positive to positive which still gives you 12-volts but doubles the amp hours. If you were to connect a 12-volt battery in series, it would create a 24-volt system!
How does the battery charge? I have one 12v battery to start appliances etc. and also used to start generator. Does the inverter charge this battery or do I need to run the generator to charge this battery???
Hi, Russell. I assume you are talking about the house battery which is a 12-volt deep cycle battery and is used to run 12-volt operations such as the lights, vent fans, water pump, and is needed to open the gas valve and provide spark for LP appliances. And if you have a generator, usually this starts off the house battery as well. Typically the 12-volt house battery is charged by the converter which is either part of the distribution center, or in a separate location but wired to it. The converter provides a charge to the house battery when plugged into 120-volt power, or when your generator is running and providing power to the distribution center. Check out our videos and blog on proper battery charging as just having the unit plugged in is not providing proper charging unless you have a multistage charger in one of the larger inverters. Your battery needs a high voltage initial charge known as the “Bulk Stage” charge, then equalizing and float charges which is does not get from the typical converter. I would recommend getting a Battery Minder from Northern Tool which conditions batteries with a high impact wave rather than boiling so there is less gassing and less acid loss. They claim it will extend the life of your batteries by over 200 cycles! Visit http://www.northerntool.com
changing the house battery tray.
My generator stops every time load is decreased. Otherwise runs fine. Example – when a/c shuts off generator stops. What causes this?
Hi, Michael. Thank you for visiting the RV Repair Club site and the opportunity to assist with your generator issue. To provide more specific troubleshooting info, we need to know the make, model, and year of your RV as well as the generator. Here are some other questions that could be important. Is your generator connected to an autostart system such as the Hughes or other energy management system? Are you connected to shoreline power and using your generator to run two roof AC units? It looks like you might have an autostart system that recognizes the need for more power when the AC unit or microwave oven is operating and it shuts off after the power is not needed?
Should my inverter be on all the time or is it unnecessary when I am connected to shore power?
Thank you for visiting the RV Repair Club site and the opportunity to assist with your inverter question. You can leave the inverter on at all times, if it’s the smaller 130 watt version for just the TV, it senses the 120-volt power available and basically shuts down itself. If it’s the larger 2000 watt version, it’s also the battery charger and will need to keep them conditioned.
how do you convert your van from having one leisure battery to two
Thank you for visiting the RV Repair Club site and the opportunity to assist with your battery question. You can increase battery capacity by connecting another 12-volt deep cycle battery in parallel to your existing battery which is positive to positive, and negative to negative. This keeps the system at 12-volts and doubles the Amp Hours. Use the same gauge wire as the original battery has going from the posts to the ground and negative side.
Regarding the video about installing the battery minder.. nice idea. However, the video didn’t describe the connections to the battery from the power converter. Is this set up assuming that the unit is stored with power? I have that battery minder but would like a battery to last longer than three years. Is there a way that was not described that the battery minder was connected while the charging system from the power converter was shut off? Maybe at the breaker box? With thanks, great vid!!!
Hi David. Thanks for visiting the RV Repair Club site and the opportunity to assist with your question concerning the battery minder. There are a couple of different systems you can get starting with the stand alone version that simply plugs into an outlet or extension cord from a 120-volt source. This is designed for temporary conditioning one battery during extended down times. The larger unit can be permanently mounted in a compartment and eyelets used to connect to the house batteries rather than the clips of the single unit. This also has to be plugged into an outlet or extension cord connected to a 120-volt power source. Neither unit is connected to the converter on the coach, rather a separate 120-volt power source. If you do not have a 120-volt source at the storage facility, I would recommend getting the solar panel option, again it does not connect to the converter. Visit http://www.batteryminder.com to see the different systems.
Is there a slid out try that can be installed for the house Batteries.
Hi, Scott. We would be happy to assist you; we just need some more information. What is the make/model/year of your RV?
Hi, Scott. Thanks for visiting the RV Repair Club site and the opportunity to assist with your battery tray question. Kwikee, which is now owned by Lippert Components Inc (LCI) makes the most popular battery tray in the RV market. They have single and double models available through most RV dealers and supply companies.
What is recommended for replacing the batteries on this Nexus Model?
Hi Brian. Thanks for visiting the RV Repair Club site and the opportunity to provide assistance with your battery question. To provide more specific information on the correct battery replacement we would need the model and year of your Nexus. However, if you are referring to the house batteries, you have several options. The house batteries need to be a deep cycle battery capable of being drained and recharged rather than an automotive type battery that would have a higher cold cranking capacity. Some manufacturers use a 12-volt deep cycle battery with either one or two depending on the amount of amp hours required. Others use 2 Six-volt batteries connected in series (positive to negative) which creates 12-volt power. I’m not sure what Nexus used, however since it was a smaller unit, I would believe they went with the 12-volt single battery? Your next option is lead acid, or AGM which is absorbed glass mat. Both will give the same amount of power at the rated “group”, however the AGM is less maintenance and will last longer but will cost more. We have several videos showing the different battery types and usage.
replaing the 2 6 vote battery’s
My RV has 2 batteries but are not connected to each other. Should they be bridged together.
I do not know what I am doing to cause the house batteries to lose their charge so quickly. It seems like I have to charge them after each trip even though I turn off the batteries while vehicle is in storage. I have tested batteries and they test good under a load. Any suggestions?
Hi, Michael. Thanks for visiting the RV Repair Club site and the opportunity to assist with your battery issue. The only way to actually test the charge capacity of a deep cycle battery is do a full charge and connect them to a 25 amp draw machine and count the time! The digital load testers are state of current charge, not capable of checking amp hours. The problem with most RV batteries is they are not charged properly over time and start to sulfate which diminishes the capacity. To properly charge the batteries you would need to connect to a multi-stage charger that initially “boils” the batteries at high voltage which breaks up the sulphation then goes into a float and equalizing charge mode. Most converters simply throw a charge when they sense the battery is low. A good product to try is the Battery Minder available at Northern Tool. This will introduce a high impact wave that conditions the battery and extends the life.
Our auto lovelers have been acting strange. Today when we returned to our unit we were loading up to move locations and the leveler panel says Low Voltage. We started the RV and let it run for 30 min. Everything else works fine. Re have tried to reset the panel by holding down the retract and enter button at the same time. We have turned the unit on and off and the leveler panel on and off. Any suggestions?
Hi, Terri. Thanks for visiting the RV Repair Club site and the opportunity to provide assistance with your leveling jack issue. To provide more specific troubleshooting information we need to know the make, model, and year of your leveling jacks and also the rig as there are some units that the RV Manufacturer adds proprietary items to.
My second try for an answer. I just recently purchased a new house battery as described above. It discharges in about three days with only the fridge running. Is this normal? Class C motor home with one house battery.
Hi, John. We apologize for the delayed response. Thanks for visiting the RV Repair Club site. The length of time a battery will hold a charge depends on several things. Even though you think you’re only running the refrigerator, you are also using battery power to run lights, vents, water pump, and other “occasional” items. If you only bought a group 24 battery, three days is normal. Your battery has an amp draw rating in hours and you can calculate the time by testing your amp draw and doing the math. I would recommend installing LED lights which will draw 10 times less power and maybe a solar panel?
Just replaced the house battery with a new one. Much like described above. I find that it only holds up about three days with only the fridge running. Is this normal? I expected it would last at least a week or ten days after being fully charged. I discovered that when it is down the step will not deploy when the door is opened.
Hi John. Thanks for visiting the RV Repair Club site. The length of time a battery will hold a charge depends on several things. Even though you think you’re only running the refrigerator, you are also using battery power to run lights, vents, water pump, and other “occasional” items. If you only bought a group 24 battery, three days is normal. Your battery has an amp draw rating in hours and you can calculate the time by testing your amp draw and doing the math. I would recommend installing LED lights which will draw 10 times less power and maybe a solar panel?
We have 2 new Trogen 6V. Deep cell hocked together. We start at 12.6. Sitting overnight it drops to 11.4. Not using anything. This seems like a big drop. We had them tested and told they were good. This doesn’t seem right.
Thanks for visiting the RV Repair Club site. The first thing I would suggest is to look for a parasitic drain from something inside the coach. Remove the negative cable from a battery and use a test light putting the alligator clip on the cable end and touching the probe to the battery terminal. If the light comes on, you have something that is drawing from the battery even if you think there is nothing on. This could be the LP leak detector, radio, or other component. You can pull the 12-volt fuses in the distribution panel to isolate what circuit the draw is coming from. If the light does not come on, you have no draw/drain and your batteries are not holding a charge which could be due to sulfation. Check out the videos on proper charging and checking battery condition with a hydrometer. This will tell you if your batteries are at 100%. (ZD: 3715)
When i’m hooked to shore power do i need to turn on the inverter to charge the batteries. I also have a kill battery switch near the passenger seat, does this need to be on for batteries to charge when hooked to shore power. I’m a little unclear what needs to be on(battery switch/inverter) when hooked to shore power
I have a 2001 Manoco Diplomat 50 amp
Hi Joey. Thanks for visiting the RV Repair Club and the opportunity to assist with your inverter. Typically when connected to shore power, your inverter will sense the presence of 120v AC so you do not have to turn anything on. The larger inverters are also battery
chargers/conditioners which will sense the 120v power and start to charge the batteries. You will want the battery disconnect switch on, only turn it off when storing the unit or not using it for a period of time.
I am having trouble with a high amp drain on my battery. After full charge my four batteries only last for about 4 hours and not enough left to start the generator. Noticed the line from the generator creates a large arc when connected to batteries and generator is off. I am thinking the battery isolator or some relay or maybe the 12 volt inverter may be the problem. I want to solve this before the batteries are ruined. Any ideas?
Hi Daniel. Thanks for visiting the RV Repair Club site and the opportunity to assist with your battery issue. The first thing I would start with is getting the batteries checked as they may have sulfated and will not keep and hold a charge? Next, pull off the negative cable to one of the batteries and using a test light, connect the clip to the cable and the light point to the terminal. If you have a parasitic drain, or amp draw from something in the coach, the light will come on. If you use a multi-meter, it will tell you how much draw. Once you verify the drain, start to disconnect components to isolate where the drain is coming from.
what is the feasibility of recharging the R V batteries with the truck batteries while driving and having a battery isolator with shutoff switch? re: slide in pickup camper.
Hi Richard. Thanks for visiting the RV Repair Club site. Some truck campers do have the ability to provide a charge from the truck engine alternator to the campers house battery system using a 7 pin plug. You can test your system using a multimeter on the house battery. Start with the engine off and check the voltage at the battery. Start the engine and see if the voltage increases. If not, you will need to retro fit the system starting with a 7 pin plug on your truck and adding the charging system to your camper which will include a battery isolator. Several companies use the Battery Isolator Manager from Precision Circuits.
I I would like to know if there is a RV club for Solar system….
Hi Tony. I do not know of any RV Club for solar however there are several good threads in the various RV forums.
Hello, any thoughts or experiences on Lithium batteries? I need to replace my Trojan deep cycle 6v and will do a lot of drycamping. My plan is to install 5 or 6 solar panels each 160W and use lithium batteries because of their low weight, long lasting, more flexible charge-uncharge cycle capacities…etc. Anyway thats what i read but need to know real life experiences.
Thx
Claude G.
Hi Claude. Thanks for visiting the RV Repair Club site and your interest in Lithium Batteries. Several RV manufacture’s are testing and offering limited options for Lithium Batteries for smaller vehicles that are designed for more boondocking adventures. I personally do not have any experience with the batteries, but have been watching closely the efforts of Roadtrek and others with their testing and sampling. The advantage of the Lithium Batteries is they typically provide more cycles, from 2000-5000 while the average Lead Acid will provide only 500-1000. The Lithium can use more amp hours typically 80% of the available power and the Lead Acid can only use a fraction of that amount. Lithium are lighter in weight which is sometimes critical for carrying capacity in smaller vehicles. Lithium does not utilize Lead Acid or other type of “liquid” so there is no gassing during recharge and they can be installed at any angle without leaking. So the advantages stack up pretty high for the Lithium, the disadvantage is the cost. You need to decide the amount of dry camping you will be doing, your power needs, how long you intend to keep the rig, and the price comparison vs a set of Absorbed Glass Mat (AGM) batteries that are very popular with “boondockers” at a fraction of the cost. If the price doesn’t scare you…by all means go with the Lithium Iron Phosphate version of the Lithium Ion Batteries.
How many solar panne does it take to run a rv one aircondition
Thanks for visiting the RV Repair Club site. As far as I know, the only company that currently has a system to run the roof AC is RoadTrek using the Lithium Ion batteries and a small AC unit on the B Vans. You can only use the solar panels to assist in charging the batteries, not used directly for the AC units.
I put a 3D diesel truck battery in my travel trailer after the regular size(24) was stolen. It weighs in at 98#s, fits in the battery tray, and is tough to steal. It also has lasted for 5 days with no recharge.
Great info. I do have quick question on small solar panel with a small led light on the dash. Have a 2008 Newmar Dutchstar 43’ coach. The solar panel is to help batteries stay charged. The red light no longer is illuminated? We’re would I go to find the control and start to check the system? I have electrical knowledge and DVOM’.s but no knowledge of solar systems?
I live in Central Oregon with freezing temps. I am storing my motorhome in a heated (50F) garage for 6 months. I do plan on taking it out for a drive and running the generator monthly when there is no snow. The rest of the time it is plugged into shore power. Is this OK for the battery to be charging while stored or should I use the battery disconnect switch while stored?
By the way, this is a 2015 Minnie Winnie 22-ft Class C with original factory battery.
Hi, Joseph. Thanks for visiting the RV Repair Club site. It’s better to leave the batteries connected and charged rather than disconnecting them with the switch as batteries will naturally lose charge and start to sulfate when not charge. However, the converter in your ‘15 Winnie is just a constant charger, not a multi-stage model and you will get some sulfation as it does not do the bulk charge, float, and equalizing stage. It would be a good idea to add the Battery Minder which sends high impact waves to break up the sulfation and will extend the life of your batteries.
I have a 2004 Dolphin motor home. Should there be a indicator for the solar panel on the roof?
Where can you buy replacement panel?
Thanks for visiting the RV Repair Club site. The 2004 Dolphin was a National RV product produced in Perris CA and a great coach. There were several types of solar panels available for that model starting with the basic smaller unit that would provide a low amp charge designed simply to keep the batteries topped off when sitting in storage or on the dealer lot. Most of these systems did not have a monitoring system, light, or LED panel showing the charge. National RV also offered various larger systems that would have these features and most dealers had them as well. I would need the model and amperage to provide more specific information, however you can buy replacement parts from any RV dealer.
I always thought that my vehicle battery will charge my generator battery, well this year, I had which I thought a major problem,. When I arrived at the Rv Camp site and hooked up all appliance worked, I thought that the
Gen battery was the problem. Had it checked and it showed fully charged, I checked everything that I thought was the problem to no avail. Finally took it into a RV shop and left unit there. Next day was called and said everything was repaired… The problem was the cables connecting the battery to the unit was corroded, once cleaned, everything worked… Simple job that caused me much headaches… Never thought of it…
Having an issue with solar panels. They charge but then when plugged into AC electric, it drains the batteries, Then have to unplug and go back to solar to charge batteries up. Any thoughts to why it is doing this?
Hi, Kenneth. Thanks for visiting the RV Repair Club site and the opportunity to assist with your solar panel issue. If your house battery is draining when plugged into electric, you have a problem with your converter in the distribution center. When plugged in, depending on the make, model, and year of your rig, the distribution center has a converter that should charge the batteries at a small amperage in older units and more in the newer digital models. Since you did not state the size of solar panels, I assume they are typical panels that usually only provide a minimal charge? Either way, the batteries should not drain when plugged into a 30 amp service. I suggest you have someone test the voltage coming to the batteries with a multimeter. Hope this helps.
Check out this site for answers to your question. https://handybobsolar.wordpress.com/
Hey Kenneth,
In some solar installations, if they also installed an INverter for 120 V AC power your on board Converter may have been disabled by disconnecting it. I have seen them unplugged or their AC breaker turned off. This is to avoid a loop where your batteries run the inverter which winds up powering the Converter which then charges the battery. Os sometimes an installer with good electrical knowledge thinks that there can only be ONE charging system and disconnects the converter.
Be sure that the installer didn’t disable the converter. If it is hooked up, then simply it is not working and with all different makes and models failures are possible so Google your brand and troubleshooting procedures.
All 3 rv batterys stolen.How do I hook up new ones ? Has 3 batterys=2001 Winnebago brave
Hello Rick,
Thank you for contacting us.
It depends on if they were 6v or 12v batteries. If they were 6v batteries two of them would have to be connected together in series to create the 12v needed. 12v batteries just need to be connected together in parallel which means all positives are connected together and then all negatives are connected together. You then have the RV positives connected to the positive on the first battery and the RV negative connected to the negative on the last battery. This allows for equal charge and draw of the system. If there were 3 batteries connected together most likely they were 12v and all connected in parallel. If you just had two they could be 6v in series. I will share a diagram showing what these configurations look like.
If you have any other concerns, please contact us at 1-855-706-3536, or chat with us on our site.
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Sincerely,
Lindsay
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