How To Connect Two RV BatteriesAnthony Day
This article may contain affiliate links where we earn a commission from qualifying purchases.
- RV batteries can benefit from being connected with the positive terminals and negative terminals
- Battery banks are the result of using multiple batteries.
- Connecting two RV batteries involves connecting the positive terminals to each other first.
- The biggest benefit is being able to draw battery power from two batteries evenly.
When learning to operate your RV, you might learn about using multiple RV batteries. You might also wonder how to connect two RV batteries?
Connecting two TV batteries involves creating a parallel connection. You’ll want to link the 12 volt batteries together by linking the positive terminals on each battery, then connecting the negative terminals on each battery. Note that for a 6 volt battery, you can create a series connection too.
We’ve been connecting two RV batteries together for years. We’ll explain the basics behind how you connect two batteries and what it’s called. We’ll go in-depth about your negative terminal and your positive terminal, what they do, and what to look out for when creating a battery bank.
Types of Connections
As an RV owner, I know how important it is to have a reliable source of power when traveling. One way to ensure that your RV has enough power is to connect two batteries together. In this section, I will discuss the three ways to connect two RV batteries: series connection, parallel connection, and series-parallel connection.
When connecting two RV batteries in parallel, the amp hours of both batteries are added together while keeping the same amount of voltage. This method is useful when you need more amp hours to power your RV. Here's how to connect two RV batteries in parallel:
Step by step on how to create a parallel connection
Before starting the wiring process, ensure that you have the following tools:
- Wire cutters/strippers
- Jumper cables
- Wrench or pliers
- Safety glasses
Parallel Connection walkthrough
Follow these steps to wire two RV batteries in parallel:
- First, disconnect the negative cable from the first battery.
- Next, connect the positive or “+” cable from the first battery to the positive terminal of the second battery.
- Connect the negative cable from the first battery to the negative terminal of the second battery.
- Finally, connect the positive cable from the RV to the + or positive terminal of the first battery and the negative cable from the RV to the negative terminal of the second battery.
Note: You can skip this connection if you only have 12v batteries. The purpose of the series connection is to link two 6v batteries together for the purpose of getting more power.
When connecting two RV batteries in series, the voltage of both batteries is added together while keeping the same amount of amp hours. This method is useful when you need more voltage to power your RV. Here's how to connect two RV batteries in a series:
As shown in the table, connect the negative terminal of one battery to the positive terminal of the second battery using jumper cables.
A series-parallel connection is a combination of the series and parallel connections. This method is useful when you need both more voltage and more amp hours to power your RV. Here's how to connect two RV batteries in series-parallel:
As shown in the table, connect the negative terminal of the first battery to the positive terminal of the second battery using jumper cables. Then, connect the positive terminal of the first battery to the positive terminal of the third battery, and connect the negative terminal of the second battery to the negative terminal of the third battery using jumper cables.
It is important to note that when wiring two batteries in parallel, it is necessary to ensure that both batteries have the same voltage and amp-hour rating. This will ensure that both batteries will discharge and recharge at the same rate, maximizing their lifespan.
Additionally, it is important to use jumper cables that are the same gauge as the existing cables in your RV. This will ensure that the current flows evenly between the two batteries and prevents overheating or damage to the batteries.
Now that you have successfully wired two RV batteries in parallel, you can enjoy increased power capacity for your RV.
Charging Two RV Batteries
When it comes to charging two RV batteries, there are two main methods you can use: parallel and series. In parallel, you connect the two negative terminals to each other and the two positive terminals to each other. This keeps the voltage at 12V, which is ideal for RVs while doubling the capacity.
On the other hand, in series, you connect the negative terminal of one battery to the positive terminal of the other, which adds the voltage of the two batteries together while maintaining the amp hours.
While charging two RV batteries in parallel or in series can be a great way to increase your power supply, there are a few precautions you should take to ensure the safety and longevity of your batteries.
The right battery charger
First, make sure to use the right battery charger for your batteries. Using a charger with too high of a voltage can damage your batteries while using one with too low of a voltage can leave them undercharged.
Secondly, be sure to charge your batteries in a well-ventilated area, as lead-acid batteries can release hydrogen gas during charging, which is both flammable and toxic. A battery receiving electrical battery power can also get hot, so ventilation helps cool down the battery banks too.
Overcharging can damage batteries and shorten their battery life. A “smart” battery charger is an excellent investment to ensure that the battery charger itself is smart enough to shut off when it has detected a battery at capacity.
Connect them right
The negative terminal and the positive terminal are sensitive, and so is the RV’s electrical system. Connecting them incorrectly can be bad news. Be sure that the RV battery charger clamps are going on the right terminals or you could short out your whole electrical system.
What is a battery bank?
You should know - you just made one! The term battery bank applies to a collection of batteries that power a device - so basically it just refers to more than one battery that is connected via the battery terminals.
People also use the term “wire batteries” to describe the process of connecting batteries and they technically mean the same thing when referring to the connection of positive and negative terminals to ensure that they are sharing electricity.