Connecting batteries in series is a common practice in the electrical industry, especially in the energy storage field. Whether you're building an off-grid solar power system or trying to create a 24 volt energy source for your boat or RV, connecting 12V batteries in series is a simple and effective way to achieve your desired voltage output.
What you'll need
Four 12V DC batteries - Ensure all the batteries are of the same capacity and chemistry. It’s important to choose deep-cycle batteries, which are designed for long-term energy delivery. You can use any type of 12V battery with this tutorial, including lead-acid, Lithium-ion, AGM and Gel.
Battery cables - You will need four positive and four negative battery cables to connect the batteries in series. Make sure each cable is appropriately rated for the amperage you intend to draw.
A voltmeter - You'll need a voltmeter to check the voltage of your battery bank from time to time during the installation process.
A battery charger - You'll also require a charger to charge your batteries when they are depleted.
Step-by-step guide
Here's how to connect four 12V batteries to make 24V:
Step 1: Verify Battery Charge
Make sure all the batteries are fully charged before attempting to wire them in series. If you're not sure if your batteries are charged, use a battery voltage tester to verify their charge levels. Ensure all the batteries are close in charge level to ensure optimal performance.
Step 2: Disconnect All Batteries from Any Load or Charger
Before you connect your batteries in series, disconnect all loads and chargers from each battery. This is to ensure that you do not short-circuit any of the batteries.
Step 3: Arrange The Batteries In The Correct Order
Place four 12V batteries in a square and label them as Battery A, B, C, and D. Connect a battery cable from the positive terminal of Battery A to the negative terminal of Battery B. Repeat this with the remaining batteries until they're all connected; Battery B to Battery C, Battery C to Battery D, and Battery D back to the positive terminal of Battery A.
Step 4: Connect The Cables
Using battery cables, connect each battery to the one adjacent to it. For example, connect Battery A to Battery B with a positive cable, then connect Battery B to Battery C with a positive cable, and so on until you reach Battery D.
Step 5: Check Voltage
Check the voltage of the battery bank using a voltmeter. You should read about 24-26 volts for the four 12V batteries connected in series.
Step 6: Charging
To keep your battery bank charged, plug your battery charger into the battery bank's positive and negative terminals, ensuring that the charger's output is the same as your battery bank's voltage; 24V in this case. Charging should take place as usual.
Safety precautions when Connecting 4 12V Batteries To Make 24V
Here are some precautions that you need to consider when dealing with batteries:
- Wear rubber gloves, eye protection, and clothing that will protect against any acid spillage.
- Make sure that the batteries are not connected to any load or charger when wiring them together.
- Always connect the positive terminal of one battery to the negative terminal of the next battery, and vice versa
- Do not over-tighten the battery terminals as this may result in damage or disconnection which can be dangerous.
Final thoughts
Connecting four 12V batteries to make 24V is a cost-effective and convenient way to create a high-voltage battery bank for your off-grid power needs or RV. Following these steps carefully and taking necessary precautions will ensure a safe and successful project. Remember to always verify the condition of your batteries before connecting them, and don't hesitate to seek professional help if you're unsure about the process.
