How many batteries do I need for my inverter?

To size a battery bank we take the hours needed continuously x watts = total watts/DC volts=amps needed.

Example: 3 hours of run time needed * 1500 watts = 4500 watts total / 12 volts DC = 375 amps. You will need a total of 375 amps of stored power in the batteries. We don’t recommend fully depleting your batteries so keep this in mind when you are calculating the number of batteries needed.

Here is another example: Let’s say you purchase a 2000 watt inverter 12 Volt. If you max out the inverter at 2000 watts, you are pulling 2000 watts /12 volts = 166.6 DC amps per hour. If you use  a 200 amp 12 volt battery you would divide 200 amp battery / 166.6 amps = 1.2 hours of run time. This is if you plan on fully depleting the battery, which we DON’T recommend. We recommend 50% depth of discharge. Since we recommend 50% depth of discharge, you would divide 1.2 hours /50%  = .60 hours. If you use 30% depth of discharge you divide 1.2 hours/30%=.36 hours.

By |2017-09-20T15:58:23-07:00September 20th, 2017||63 Comments

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  1. Cherilyn Marina Stanneart September 30, 2018 at 1:54 pm

    I just need to know how much battery I need for a 2000 watt inverter. I don’t want to do math. I want an answer.

    • Laura October 4, 2018 at 2:49 pm

      Hello,
      If you were to max out the inverter at 2000 watts, 12Volts, you will be pulling 166 DC amps an hour. If you purchased one of our 12Volt 100 amp batteries you would get 100amp battery /166 amp load = .60 hours of run time. I hope this helps!

  2. David October 10, 2018 at 7:18 am

    I have four 12vlts batteries 200amps if i connect them in series and parallel can i get 24v and 800amps? or will i get 24v and 400amps? please i need an an answer

    • Laura October 10, 2018 at 8:17 am

      Hello David,
      You will have two banks of 200 amps each. This will give you a total of 400 amps.

  3. Gary November 1, 2018 at 4:09 pm

    I need 500watts for 8 hrs 240 v ac and 12 volt batteries how many batteries will I need

    • Laura November 5, 2018 at 8:43 am

      Hello,
      You will need 2 of our 200 amp batteries or 4 of the 100 amp batteries.

  4. Ben November 4, 2018 at 5:50 pm

    Hey
    I just purchased a 2,300 watt inverter and am looking to power a speaker that pulls about 500 watts continuous, 1,300 watts peak. Which battery should I look into purchasing to power this? Will I need two?

    • Laura November 5, 2018 at 8:41 am

      I would recommend 2 of our 100 amp hour batteries. AGM or Lithium would work.

    • Laura November 14, 2018 at 10:40 am

      Hello Ben,
      How long do you plan on running the speaker before you will be able to recharge the battery?

  5. Laura November 14, 2018 at 10:39 am

    If you were to max out your 3500 watt inverter you would need a total of 3492 of stored amp capacity. The number of batteries will be determined by the size of the battery you plan on using.

  6. Wes November 27, 2018 at 12:33 am

    I need 1000 watts for 8 hrs 240 v ac and 12 volt batteries how many batteries will I need?

    • Chrissy December 26, 2018 at 3:19 pm

      If you are running 1000 Watts an hour for 8 hours on a 12 volt system you are consuming a total of approx. 667 DC amps. If you are using 200 AH 12 volt AGM batteries we would recommend 7 batteries. If you are using 200 AH 12 volt Lithium batteries we would recommend 4 batteries.

  7. Afwangs December 23, 2018 at 3:23 am

    Hello sir, please i have 12v, 100 amph battery, and 12v 1000 watts inverter, please how many hours can i run this load please help me sir i need urgent answer sir?

    • Chrissy December 26, 2018 at 3:23 pm

      1000 Watts / 12 Volts DC = 84 DC amps consumed. From fully charged to fully discharged this battery would last about 1 hour. We don’t recommend depleting AGM batteries below 50% to prolong the life of the battery. If you are using a 100 AH AGM battery we would recommend approx. 45 minutes of use at 1000 Watts on a 12 volt DC system

  8. Clifford Huntley December 27, 2018 at 2:45 pm

    I have a 3000 watt pure sine wave inverter. And right now I have 2 centennial agm CB12-260 batteries. I will be charging with both solar and wind. But my question is, i need to run at most 1500 watts none stop 24/7 i am thinking i need more batteries, these cost a bundle lol but if i need more? How many more and what do you recommend adding to this bank? Thank you.

    • Chrissy December 28, 2018 at 9:14 am

      If you are using a 12 volt DC inverter and AGM battery bank we recommend your bank be at least 6000 Amp hours for a 24 hour period. (1500 Watts per hour x 24 hours = 36000 Total Watts / 12 Volts DC = 3000 DC Amps consumed x 2 so as not to deplete your batteries below 50% = 6000 Amps).

  9. joshua January 4, 2019 at 1:27 pm

    I have a question I am looking to power a slurry vacuum at 1600 watts for 6 hours. This brings me to 9600 watts total. if i divided this by 12 it gives me 800 amps. would you recommend 5 200 AH batteries?

    • Chrissy January 4, 2019 at 2:04 pm

      We don’t recommend depleting your battery bank more than 50% to prolong the life of your batteries. With your draw of 800 amps we would recommend a bank that is at least 1600 amps to keep from over depleting your batteries. 8 of our 200 AH 12 volt batteries would create that bank.

  10. JEREMY GOLLYHORN January 7, 2019 at 4:57 pm

    I want to run a beverage fridge says it’s 80watts on the label for about 10 to 12 hours any advice on an inverter and batteries to do this?

    • Chrissy January 8, 2019 at 7:45 am

      We recommend running the inverter at 50% capacity to extend the life of the system. The pwri18012S would be a good fit for this beverage fridge that uses 80 Watts. For the battery your math looks like this: 80 Watts x 12 hours = 960 Watts used / 12 Volts DC (voltage of the recommended inverter) = 80 DC amps consumed in 12 hours of use. We don’t recommend depleting your AGM battery below 50% to prolong the life of your battery. With that in mind we would recommend a 200 AH 12 volt AGM battery. If you are using a lithium battery you can deplete it much more deeply without negatively impacting the life of your battery, so a 100 AH Lithium battery would be a good battery alternative to the AGM.

  11. JEREMY GOLLYHORN January 8, 2019 at 8:44 am

    Hey thanks a lot for your advice one more question now with this inverter if I wanted to plug in SE laptop and some LED strip lighting not too sure of the wattage but doesn’t seem like it would draw that much with this inverter still work or should I get a bigger one

    • Chrissy January 9, 2019 at 9:55 am

      It’s always better to err on the side of caution and have an larger inverter you are sure will work your devices. If you are adding more devices you may want to go to the 300 watt model pwri30012s. Using more power will deplete your batteries faster as well, please keep that in mind when planning your system.

  12. Naveed January 13, 2019 at 2:59 am

    Sir I have 24V,1500VA inverter and two batteries of 150Ah,12V each.Can I connect with them in series.Explain with formulae.plzzz help immediately.

    • Chrissy January 14, 2019 at 10:44 am

      To size a battery bank we take the hours needed continuously x watts = total watts/DC volts=amps needed. Example: 3 hours * 1500 watts = 4500 watts total / 24 volts DC = 187.5 amps. You will need a total of 187.5 amps of stored battery power to last 3 hours. Remember, we don’t recommend depleting AGM type batteries below 50% to prolong the life of the battery. Lithium batteries can be much more deeply depleted without having a negative effect on the battery. Keep this in mind when calculating the number of batteries needed. Please see our FAQ’s for diagrams showing how to connect your batteries in series.

  13. Jay Henry January 14, 2019 at 6:27 pm

    Electrical is not my strong point I just bought a hundred watt solar panel with a solar charge controller I have a vector 2500 watt power inverter that powers up to 21.2 amps 2 deep cycle battery group 24. One of the batteries is 915 cold cranking amp and the other one is 625 MCA. I have them hooked up parallel to the inverter and the solar controller and I’m wanting to power a full size freezer in my garage Arrow refrigerator freezer in my house and perhaps a coffee maker from time to time if the power goes out. Any idea how long the existing one will last at full charge and what is the best lithium battery size model for my needs and how many do I need thank you

    • Chrissy January 15, 2019 at 2:39 pm

      We recommend keeping your batteries the same composition. If you plan to use lithium batteries, all of the batteries in your bank should be lithium. That holds true for any battery type. We calculate battery size and longevity based on Amp Hours, the cold cranking amps of your battery is a completely different measurement. You will need the Amp Hour (AH) rating for your battery for sizing your power use on an inverter. To size a battery bank we take the hours needed continuously x watts = total watts/DC volts=amps needed. Example: 3 hours * 1500 watts = 4500 watts total / 12 volts DC = 375 amps. You will need a total of 375 amps of stored battery power to last 3 hours on a 12 volt system. Remember, we don’t recommend depleting AGM type batteries below 50% to prolong the life of the battery. Lithium batteries can be much more deeply depleted without having a negative effect on the battery. Keep this in mind when calculating the number of batteries needed. Here is a link for our AGM and Lithium type batteries: https://theinverterstore.com/product-category/bdc/

  14. Elias January 16, 2019 at 9:13 pm

    I need 400watts for about 8hrs. I have 2 pcs of 12V/150Ah and inverter of 2kW. Is it possible? And if not possible for how long will I get 400watts?

    • Chrissy January 17, 2019 at 1:06 pm

      400 Watts x 8 hours = 3200 Watts / 12 Volts DC = 267 DC amps. For most batteries we don’t recommend depleting below 50% to prolong the life of your batteries. With that in mind we wouldn’t recommend using 400 Watts on a 300 AH bank at 12 Volts DC for more than 4.5 hours. If you are using lithium type batteries you could go for the full 8 hours. Here is a link for our AGM and Lithium type batteries: https://theinverterstore.com/product-category/bdc/

  15. Danny Hutsell January 21, 2019 at 3:12 am

    I am trying to decide on buying a power generator or just getting a large invertor for us when the electricity goes out. If I buy a 5000 watt invertor, and then hook it up to my car battery in my car, which is just outside my front door, could I then run some extension cords from the invertor into my house and power the lights and a small appliance or two? And use my car as the battery recharger? Just start the car and let it run and keep the battery charged that way? I’m assuming I might have to buy a better battery (possibly a deep cycle) to install in my car? Or am I going to have to buy several batteries and hook them up on the ground, outside of my car, by the invertor, and then run charging cables (maybe #2 gauge wire) from my car to the battery bank that I have set up outside my car that is hooked up to the invertor? Is this a feasible way to approach supplying my emergency power? Would it save me any money? Or am I going to spend just as much or more on a high capacity invertor and batteries as I would just a good quality generator? Because I’m really not wanting to spend more than a thousand dollars on this emergency power situation. Please let me know & thanks you very much.

    • Chrissy January 21, 2019 at 9:51 am

      It is possible to power your home in a set up like you have described here. Your inverter needs to be within 12 feet of the battery, but you can run a good quality extension cable from the inverter to your appliances up to 100 feet. You’ll need to figure out your power consumption, the capacity of your battery, and the recharging power of your alternator to see if you will need additional batteries. To size a battery bank we take the hours needed continuously x watts = total watts/DC volts=amps needed. Example: 3 hours * 1500 watts = 4500 watts total / 12 volts DC = 375 amps. You will need a total of 375 amps of stored battery power to last 3 hours on a 12 volt system. Remember, we don’t recommend depleting AGM type batteries below 50% to prolong the life of the battery. Lithium batteries can be much more deeply depleted without having a negative effect on the battery. Keep this in mind when calculating the number of batteries. Remember, that AH (Amp Hours) are different than cold cranking amps. You will need to find the AH rating for your car battery for this equation. In this scenario you are using 125 DC amps per hour (1500 / 12 = 125). To keep up with that we would recommend an alternator that is approx. 250 amps. Your numbers may be different based on your actual power use. It is possible to add auxiliary battery(s) to your system for more battery capacity. Please contact us at customerservice@theinverterstore.com for more details and assistance.

  16. Danny Hutsell January 21, 2019 at 12:17 pm

    Wow…. Thank you so much for getting back to me so soon. I will do all the calculations and then get back to you with any questions I have. WE WILL BUY OUR EQUIPMENT FROM YOU ALL….. THE EXPERTS…. I imagine we will need to get a new lithium battery and of course we need an invertor….. but how do I know if the alternator in my vehicle is a 250 amp alternator. Is it stamped on the alternator somewhere? The vehicle is a 2018 Kia Sorento, so I doubt seriously that it has that big of an alternator. Please let me know how to check the alternator capacity, and I’ll start working on the rest of the calculations. Thanks! Danny Hutsell

    • Chrissy January 21, 2019 at 2:29 pm

      If your vehicle manual doesn’t tell you the amps for your alternator you may need to stop at your mechanic who can tell you the size of your alternator, your dealer may be able to tell you as well. Your alternator is most likely not 250 amps. That’s fine it just means you’ll be depleting your battery as you use power, just not as fast as you would without the alternator. The inverter will shut off once the battery voltage gets to low. This helps safe guard you against over depleting your starter battery. If you’re using auxiliary battery(s) we also recommend a battery isolator. This allows you to use your alternator to charge your auxiliary batteries without depleting your starter battery.

  17. Latrina Dakota January 23, 2019 at 1:42 pm

    I have a 5000 watt inverter by strongway for my food truck please help me understand how many batteries are required to push this monster. The hot water heater is 2000 watts. The water pump says 120vac/2A/60Hz. A flat screen tv, a refrigerator, small deep freezer and and, a double warmer with oven elements.

    • Chrissy January 24, 2019 at 1:33 pm

      Your battery need really depends on the watts you are using and for how long. To size a battery bank we take the hours needed continuously x watts = total watts/DC volts=amps needed. Remember, we don’t recommend depleting AGM type batteries below 50% to prolong the life of the battery. Lithium batteries can be much more deeply depleted without having a negative effect on the battery. Keep this in mind when calculating the number of batteries needed. We’d be happy to help you estimate your battery bank needs, just let us know your total watts used per hour, how many hours you’ll be powering them from battery and the DC voltage of your system.

  18. Paul February 10, 2019 at 1:32 am

    I need to power a 3kva inverter, how many 12v batteries do I need to do such?

    • Chrissy February 11, 2019 at 10:12 am

      That depends on the power you are using and for how long. To size a battery bank we take the hours needed continuously x watts = total watts/DC volts=amps needed. Example: 3 hours * 1500 watts = 4500 watts total / 12 volts DC = 375 amps. You will need a total of 375 amps of stored battery power to last 3 hours. Remember, we don’t recommend depleting AGM type batteries below 50% to prolong the life of the battery. Lithium batteries can be much more deeply depleted without having a negative effect on the battery. Keep this in mind when calculating the number of batteries needed.

  19. Seun February 12, 2019 at 9:43 pm

    Helo, have a 1kva inverter and 200mah battery but my supply is not bringing light to my house,the voktmeter(output) keep blinking,what can be the problem

    • Chrissy February 13, 2019 at 2:25 pm

      If this is an AIMS power inverter the AIMS technical support team will be happy to help you troubleshoot your inverter. They can be reached by phone at 888-417-8673 option 2 Monday – Friday from 7:00 am to 4:00 pm Pacific time.

  20. Melvin Thomas February 17, 2019 at 2:15 am

    i have 300 watts total power load and my inverter is 1000 Watts. i need to work this 3 hours total. kindly let me know how much amp battery i need to fix for the same.

    • Chrissy February 18, 2019 at 7:29 am

      We would need to know the DC voltage of your inverter to answer this question. For example if you are using a 12 volt DC inverter and AGM type batteries we would recommend a bank of at least 150 AH (300×3=900 Total Watts 900/12Vdc=75 DC amps consumed 75×2 (so you don’t over deplete AGM batteries)=150 AH recommendation).

  21. Mark February 26, 2019 at 8:10 am

    Please i have 4 battery which is 200ah and 3kva 24v inverter, i want to know what watt and how many solar panel module, also will i connect it in series or parallel,

    • Chrissy February 26, 2019 at 12:59 pm

      The amount of solar panels you will need is based on wattage used per day. Here is an example on how to determine the amount of solar panels you will need: If you use 7000 watts/5 hours of direct sun (US average) you need 1400 watts per hour of sun that would equal 6 of the 265 watt panels. Our inverters do not connect directly to solar panels. You will also need a solar charge controller to charge your batteries from solar panels in this set up.

  22. Peceli savou junior February 26, 2019 at 12:26 pm

    I’ve got a 3000 watts inverter an a 12v 70ah duracell batter how many battery do I need for my refrigerator It’s 90w

    • Laura February 26, 2019 at 1:46 pm

      Hello, your refrigerator pulls 7.5 amp per hour. If you have a 70 ah battery, it will last 70/7.5=9.3 hours if you fully deplete your battery. We don’t recommend fully depleting your battery because it hurts the overall life of your battery. If you use 50% depth of discharge you will have about 4.6 hours of run time. Refrigerators run intermittently so it will also depend how often your refrigerator kicks on to cool.

  23. Amin March 3, 2019 at 9:39 pm

    Hi
    I have a 3000w inverter do i need a second battery?
    I just need to run my sawzall or my vacuum for less than 5 min! Still need second battery?
    My current battery is 70 amp

    • Chrissy March 4, 2019 at 9:27 am

      To start 3000 Watts on a 12 volt system you would need a battery bank that is at least 250 AH (3000 / 12 = 250). Based on this you would need additional battery(s).

  24. Anthony March 4, 2019 at 12:37 pm

    I have 16 batteries, 4 in parrallel each with 200 amp hours. Connected to a 48 volt inverter . How many hours will it run for ? Thanks

    • Chrissy March 7, 2019 at 8:51 am

      Unfortunately we can’t answer this question without knowing you power draw. If each of your 16 batteries are 12 volts 200 AH and you have used them to create groups of 48 volts each your total bank is 48 volts 800 AH. The run time would depend on how many AH you are using per her and how deeply you deplete your batteries. To figure your AH used take the hours needed continuously x watts = total watts/DC volts=amps used.

  25. Du Toit Le Roux March 6, 2019 at 12:09 am

    Hi ive got a 2.5 kw 24volt inverter if i put 6 x 170a/h batteries with it how long can i use it if my demand is a 300watt?

    • Chrissy March 7, 2019 at 9:10 am

      Without knowing the DC voltage of your batteries we can’t accurately answer your question. If we assume that your batteries are each 12 volt DC you could create a 24 volt bank that is a total of 510 AH. If you only deplete this to 50% that means you have 255 usable DC amps before over depleting your battery. 300 Watts on 24 volts consumes 12.5 DC amps per hour, so about 20 hours if your batteries are 12 volts each and you don’t deplete more than 50%

  26. Harrison March 16, 2019 at 2:41 pm

    Hello, I have 5Kv inverter and 8 batteries of 200Ah each and yet it doesn’t last for more than 4 hours before it goes off at night. What could be the cause?

    • Chrissy March 18, 2019 at 8:41 am

      Without knowing your DC voltage or your actual power draw it’s hard to say. If you are pulling 5000 Watts per hour on 12 volts DC that is 417 DC amps per hour. If your batteries are 12 volts DC each set up in a 12 volt bank your total bank is 1600 DC amps. From fully charged to fully discharged that would be less than 4 hours of use. Your inverter will shut down before the batteries are fully discharged, once the voltage drops too low.

  27. starstern May 22, 2019 at 11:48 pm

    Cuisinart STM-1000 Digital Glass Steamer, Stainless Steel uses 1800 watts would like to operate this by dc ,so guess will get KRIËGER-2000-Watt-Power-Inverter/dp/B07572PPR3 24 volt ,now which and how many battery to use ?

    • Chrissy May 30, 2019 at 9:48 am

      1800 / 24 = 75 DC amps consumed per hour. The size of your battery or battery bank would depend on how long you drew this power for. Remember, we don’t recommend depleting most deep cycle batteries below 50%.

  28. DAvid Sheals June 6, 2019 at 3:12 pm

    I just purchased a 12,000 invert ,what kind of batteries size and how many do I need

    • Chrissy June 7, 2019 at 10:31 am

      That depends on your use and the voltage of your inverter. To size a battery bank we take the hours needed continuously x watts = total watts/DC volts=amps needed. Example: 3 hours * 1500 watts = 4500 watts total / 12 volts DC = 375 amps. You will need a total of 375 amps of stored battery power to last 3 hours. Remember, we don’t recommend depleting AGM type batteries below 50% to prolong the life of the battery. Lithium batteries can be much more deeply depleted without having a negative effect on the battery. Keep this in mind when calculating the number of batteries needed.

  29. Charlie June 8, 2019 at 7:56 am

    I have a 2000w inverter and I need to know what battery to get to run at least 1500w for 10 hours. For a solar panel system.

    • Chrissy June 11, 2019 at 8:41 am

      We would need to know your DC voltage to answer this question. 1500 x 10 = 15000 / DC Voltage = DC amps consumed. Remember, we don’t recommend depleting AGM type batteries below 50% to prolong the life of the battery. Lithium batteries can be much more deeply depleted without having a negative effect on the battery. Keep this in mind when calculating the number of batteries needed.

  30. Kpaynejr86 July 19, 2019 at 12:37 pm

    I wave a swamp cooler I would like to run fully on solar and batteries. I have two 300w 36v panels, an epever 30amp charge controller, and a 24v 800w inverter. The swamp cooler uses about 280-350w when running. How many batteries would I need to power this 24/7? I’m hoping that while the panels are charging during the day that it will also provide enough power to run the swamp cooler all day and have the batteries take over when the panels lose sun power. Thanks for any and all advice.

    • Chrissy July 23, 2019 at 11:55 am

      If you are using 350 Watts per hour for 24 hours on a 24 volt system you would consume 350 DC amps from battery. To avoid over depleting the battery we would recommend using lithium batteries or having a bank that is 700 AH.

  31. np2fz July 23, 2019 at 5:47 am

    would like to purchase an inverter and batters to handle 2580 watts running for 12 hours per day for a solar project. Can you recommend how many batteries I would need as well as the inverter.

    thanks.

    • Chrissy July 23, 2019 at 12:00 pm

      We recommend running the inverter at 50% capacity to extend the life of the system. So we would recommend a 6000 Watt inverter like this one: https://theinverterstore.com/product/6000-watt-pure-sine-inverter-charger/ As for batteries 2580 x 12 = 30960 Total Watts / 24 Volts DC = 1290 DC amps consumed. We would recommend a 24 volt DC bank about twice that size to keep from over depleting your batteries (this is too large of a bank for our current lithium batteries).

  32. np2fz July 23, 2019 at 5:49 am

    DC voltage is probably going to be 24 volts coming in from the solar panels

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