Tuesday, October 3, 2023


What is the best option to connect six 6-volt batteries for RV?

Dear Dave,
I wonder about the best way to configure six 6-volt batteries. I have the traditional method of connecting two 6-volt batteries in series and then connecting them parallel to two additional pairs. But I wonder about the option of connecting the first three batteries in parallel and a second set in series. Does either setup provide a better, stronger, or longer-lasting power supply, or do both configurations yield identical results? —Colin

Diagram provided by Colin:

Dear Colin,
Your RV needs 12-volt power to run items such as lights, vents, water pump, and appliances that run on LP such as the refrigerator and furnace. When you connect two 6-volt batteries in series it is positive to negative, which creates a 12-volt bank but does not double the amp hours.

According to your diagram, the amp hours is 200, so when you connect the first two in series you get 12 volts and 200 amps. When you do this for the second and third pairs, you have three 12-volt banks with 200 amp hours each. Then, when you connect those pairs parallel, it is positive to positive and negative to negative, which keeps the voltage at 12 volts but now doubles and triples the amp hours. In your traditional method, you have 12 volts and 600 amp hours.

Optional method

If you connect the left side three 6-volt batteries in series, which is positive to positive and negative to negative, you create a 6-volt bank with 600 amp hours. Same with the right side three 6-volt batteries. When you connect the two, three-battery banks, you get 12 volts but still 600 amp hours.

So you are getting the same results in voltage and amp hours but adding three more cables and much more maintenance, in my opinion. Therefore, I do not see any advantage, but I do not see anything that would not make this work.

Let’s put it out there to see if anyone has used this optional setup. I wonder whether one method produces optimal power for a longer period or do both methods produce the same results?

 You might also enjoy this from Dave 

6-volt or 12-volt batteries for RVs—Which is better?

Dear Dave,
I keep reading about using two 6-volt batteries in series for RVs. Why? It seems like it would be simpler to have one 12-volt or two 12-volt batteries in parallel. Sorry, still a newbie trying to figure all this stuff out. —Richard, 2023 Geo Pro 19FDS

Read Dave’s answer.

Dave Solberg is a leading expert in the RV industry and the author of the “RV Handbook.”

Read more from Dave here


We have a popular forum for Ask Dave. Please be as brief as possible. Attach a photo or two if it might help Dave with his response. Click to visit Dave’s forum. Or send your inquiries to him using the form below.

Click or drag a file to this area to upload.


Dave Solberg
Dave Solberghttp://www.rv-seminars.com/
Dave Solberg is a leading expert in the RV industry and author of the “RV Handbook” as well as the Managing Editor of the RV Repair Club. He has been in the RV Industry since 1983 and conducts over 15 seminars at RV shows throughout the country.


3.5 2 votes
Article Rating
Subscribe to comments
Notify of

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Inline Feedbacks
View all comments
David Solberg
26 days ago

Yes, I did slip! I meant to say the two 6-volt batteries that are now connected in series to create a 12-volt bank should be connected parallel which would be positive to positive, negative to negative.

I said “series” which was not correct

2 months ago

I was under the impression that positive to positive is parallel, not series. Did I miss something?

26 days ago
Reply to  Russ

You’re correct. Dave slipped up.

Sign up for the

RVtravel Newsletter

Sign up and receive 3 FREE RV Checklists: Set-Up, Take-Down and Packing List.