Two Inverters on one Battery Bank

Yes, you can have two inverters connected to one battery bank. We can have two different kinds of inverters, these are:

  • Synchronized inverters running the same loads
  • Separate inverters running separate loads

You need to consider certain factors to ensure a safe and efficient setup, which we will discuss later in the article.

Key Takeaways
  • When connecting multiple inverters to a single battery bank, you can either use synchronized inverters for the same load or separate inverters for different loads.
  • It’s important to ensure the battery bank has enough capacity and the right C-rate to handle the total power demand of the inverters.
  • Never connect the outputs of two or more inverters that are not synchronized.

Synchronized Inverters

If you plan to use two inverters simultaneously to power the same appliances, you must choose inverters that can synchronize their outputs.

Some off-grid inverters are specifically designed to work together in parallel and include built-in synchronization features. They are usually connected with an ethernet cable to synch their output. That way, they can put out the same voltage and frequency, and their sinus waves are synched.

Below is a diagram of such a system running one or more appliances.

coupled and synchronized inverters connected to one battery
coupled and synchronized inverters connected to one battery

With synchronized inverters, you can create 3-phase systems. This is not possible with separate inverters.

Three Victron Quattro inverters wired for 3-phase output (source)

Separate Inverters

If you choose this setup, it can have two reasons:

  • You want to add an inverter to your existing system for more power.
  • You want a more efficient inverter to run your fridge 24/7

If the two off-grid inverters are meant to power different sets of appliances or loads, synchronization might not be necessary. In this case, you can use two separate inverters connected to the same battery bank, each serving a different load.

A diagram of such a system can be seen below:

separated outputs from to inverters coming from one battery
separated outputs from to inverters coming from one battery

Things to keep in mind when you wire two inverters to one battery

Connecting two inverters to the same battery is easy.

But there are some extra calculations and considerations we need to do.


The C-rate is how fast a battery can discharge. For example, a 12V, 100Ah lead-acid battery has a c-rate of 0.2.

0.2 x 100Ah = 20A

This means you can discharge the battery at 20 amps to achieve a long battery lifespan. The total power will be:

20A x 12V = 240W

So you can only have a 240W inverter on a 12V, 100Ah lead-acid battery.

Now, lithium has a C-rate of 1. Using the same example of a 12V, 100Ah battery:

1 x 100Ah = 100A

100A x 12V = 1.200W

We can see that we can have a larger inverter if we use lithium.

The point I want to make here is that you cannot just add another inverter. You need to calculate the C-rate of your batteries and the inverters.

Let’s say you have a 2000W inverter and want to add another 1000W inverter.

2000W + 1000W = 3000W

3000W / 12V = 250A

250A x 1C = 250Ah

You need a 12V, 250Ah battery to support a 3000W inverter power.

If you have a lead acid battery, multiply by 5 (C/5 or 0.2C):

250A x 5 = 1250Ah

Wiring and Safety

Proper wiring and safety precautions are essential when connecting multiple inverters to a single battery bank. Use appropriately sized cables, fuses, and circuit breakers to ensure a safe and efficient setup.

  • Read my guide on how to size wires here
  • Read my guide on how to size fuses here


It is possible to connect two inverters to the same battery bank. Either you choose inverters that can communicate with each other or you have two separate inverters powering a different load.

Never connect the output of two separate inverters.


How many batteries can be connected in parallel to an inverter?

You can have as many inverters in parallel as you want. Remember that the inverters need to communicate with each other OR have each their separate load. Never connect the output of two or more inverters that are not synchronized. You also need to keep in mind the C-rate of your batteries.

Read more: How many batteries for a 3000W inverter?

17 thoughts on “Two Inverters on one Battery Bank”

    • if you have a 48V battery, which I hope you do, then you will pull 400A+ from your batteries. If the battery is lithium and 15kW at 48V, I assume 3 100Ah, 48V server rack in parallel, then you can pull max 150A. So your setup is not properly balanced.

      • hi Nick. thanks for putting this up.
        you specified to
        “Never connect the output of two separate inverters together.”

        is that just a recommendation and yet it can still work somehow? or is it a definite no no and dangerous or potential to wreck the equipment?

        thanks in advance

  1. Hi nick my friend has a estaurant set up,i installed 2 inverters ,running different lines each with 2x 200ah batteries,the batteries are linked in series which means i only have 200ah with 2 x 200ah the power doesnt last long enough when its loadshedding, can i connect the 2 inverters and sonehow connect the batteries to get 400ah out of the system,thx

    • Two batteries in series or parallel have the same energy density. Series: voltage increases, parallel: capacity (ah) increases.
      12V, 200Ah x 2 batteries in series = 24V * 200Ah = 4.800Wh
      12V, 200Ah x 2 batteries in parallel = 12V * 400Ah = 4.800Wh
      The inverters will connect to the battery bank (two batteries in series or parallel). Look at my diagrams in the article.
      I assume you have a 24V inverter, so no you cannot have 400Ah, but that’s not important, it’s the Wh that counts.

  2. Hey nick, nice read! I recently ran 2 sun gold 6500w inverters in parallel and kept my old 5k up and running also, all pulling and charging the same set of batteries but They were feeding separate power boxes and worked great for about a week! Now the two parallel ones popped a fault 57 code and can’t find nothing on how to correct, tech support seems quite slow with them! Could the battery runs from both have possibly caused you know? Just seeking any answers now! Thanks in advance.

  3. Can you run the inverters in series from the battery? Ie is it possible to have a 96v battery source and use 2 48v inverters to split that 96v dc to the inverters.

    In my case it’s how to possibly utilise a 80v 3kwh electric motorbike battery to 24v inverters as trying to find a 80v one is not easy etc.


    • No, that is not possible. The voltage will be the same (96V) over the two inverters. You could split the battery if that is possible. But there are some other concerns involved with that.

  4. What about the charge settings on each inverter?
    Using two independent inverter/chargers, would they both be configured to charge the common bank of batteries?
    In my case, I’m considering two inverters, an MPP LV3048MK (which I already own) + a SolArk or EG4 15/18K model.

    I know that the BMS on most LiFE batteries can only communicate with one inverter…. so if I needed to only use one of them to charge the batteries, that’d be fine. But I guess if both were connected to different banks of solar panels too, it’d be nice to have both able to charge (using the same bulk/float voltages I assume!?)

  5. I have 2 x alpha ess 6S which do not parallel but can run as grid connect or offgrid.
    I am off grid,… is there a way of having one inverter as the off grid unit and the other inverter to think the first is a “grid” and so combine outputs and put into 1 circuit to power a heavier load than 1 can handle? Does the problem occur of perhaps setting the “grid connected inverter” to priority usage before taking power from the “grid forming” inverter, and so the battery of one would be cycled mostly with limited opportunity to charge as the other grid forming inverter would be fully charged unless the second went flat or could not provide the total load?
    Is there some other workaround apart from purchasing dedicated offgrid paralleled inverters?

  6. Good morning,
    I am Corrie Olivier, I want to know if I can do any damage to the inverter if the input voltage is sligthly higher than specified.
    In this case 102v input. can I do damage with say 110v.
    Thank you,
    For now.


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