1000W Inverter: How Many Batteries You Really Need

In today's video, I'm diving into a common question in the off-grid solar world: How many batteries do you actually need for a 1000W inverter? You might be surprised to know that many guides out there get this wrong. I'm here to set the record straight with detailed calculations and comparisons.

We'll start by revisiting the concept of limiting current to 100A by adjusting the battery voltage, as discussed in my previous video about 3000W inverters. Then, we'll specifically analyze what's needed for a 1000W inverter.

Lead-Acid vs Lithium Batteries:
I'll compare lead-acid batteries, known for their .2C C-rate, with the more robust 1C C-rate of lithium batteries. You'll see how the amount of batteries required varies greatly between these two types, and why getting this right is crucial for the efficiency and longevity of your system.

Wire and Fuse Sizing:
An often overlooked but crucial aspect! I'll guide you through selecting the appropriate wire and fuse sizes for your system, explaining why these choices matter and how they contribute to overall safety and efficiency.

Why Size Matters:
Under or over-sizing your battery can lead to inefficiency and even damage. I'll break down why it's important to match your battery size accurately to your inverter's requirements.

Free Resources:
Also, don’t miss out on my free diagrams to help simplify your DIY solar power projects. Check the first link in the description to sign up and receive these valuable resources directly in your inbox.

00:00 Introduction
00:19 Calculating current
00:59 Lead-acid
02:07 Lithium
02:47 Why do we size like this?
03:39 Wire and fuse size

[sheds]

Thank you for simplifying and sharing your knowledge. As a direct result of your previous video, I have abandoned my Lead Acid, and moved to a Lithium to power my 1000w Inverter. It works perfectly. All I need now is for spring sunshine to come 🤣

[italianoboy]

Ok, I'm new to inverter, solar-powered, and batteries. Your video explained it well. I WAS going to get 3k watt inverter with just one LiFePO4, rated at 100a. I know now that I would need at least 3 100amp batteries to work with a 3k w inveter.

[robertcollins]

Great info possible the first video I have been able to understand Thank you

[budmartin]

To get 1000W from the AC output of the inverter, the input power to the inverter will be higher than 1000W due to the inverter efficiency, 80% is typical, so the current draw from the battery will be 83A/0.8 = 103A.

[nattapongsookrojnirun]

very great video !!!
at 2:42 what should we concern if we use 12V, 100ah lithium x 2 pleazzze ? or should it be better to use 12V 200ah ? cant figure it out that part, been watching this over 5 times now 😂

[jerryndembeka]

Please do another calculation video with 2000W inverter with 24V batteries. Your videos are very helpfully. Thank

[faisalalhashar]

Hello, thank you for excellent and outstanding videos. I have a question, I have 4 100 Amps AGM batteries on my boat. I also have a Victron MultiPlus 2000VA and Digital Multi Control 200/200A GX. From your video, it seems that I will need an additional 400 Amps to cope with my 2000w inverter - right? My question is, until I do add the needed batteries can I still use 1000 w appliances in the current setup without the overheating or any other risks?

[Abiola-yz]

Your videos are so succinct and serve as refresher for me as an experienced Solar PV Professional. However, this particular video needs reveal. For example, if an inverter is rated 12V/1000W (assuming 100% efficiency), it means it can supply max. 83A. Then a typical Lithium battery rated 12V/100AH at 1 C rate will draw maximum of 100A. The system will definitely overheat because what is required for the battery charging 100A is higher than what the inverter can supply which is 83A at 100% efficiency. Thanks.

[TUVIX]

I like your video but I can't figure out how many batterys I need. I want to power a computer pulling 1500w at the wall at night. If I have a solar pannel charging the batterys during the day? Is it even posible to power for that amount of time?

[jackfromthes]

I like your videos. I just received your free diadgrams and am working my way through them. On page 5 of the free diagrams you say a lithium battery can provide a current of 0.5C. But at 2:10 in this video you say a lithium battery can provide 1C. Can you please clarify?

[loumusa]

Thanks for the video. As a result I want to replace both my deep cycle 100amp lead acid batteries with 2 Lithium 100ah batteries. My inverter is a Sensata Technologies CSW1012 1000W Inverter. Will this set up work for my situation?

[AntSmartFV]

I just bought A 12v 4000w power inverter im planning to parrallel 6 lead acid batteries that i have , what busbar do i need ? I have an RV truck, what are you recomendations?

[victorgallardo]

Thank you very much for the video, I am learning a lot, but it is not clear to me if a 200Ah (lithium) battery would be better than a 100Ah? Would it be more efficient?

[victorjoseph]

IF i only charge my lipo4 12v 100ah battery with solar panels i do not need the invertor right? for i just want to only charge the battery for augmenting my Bluetti EB3A 268Ahcapacity and have 1080 usable Wh with my EB3A battery. is this correct? or am i mistaking? 1080+268= approx 1300Wh. instead of just the 268 watts. since the EB3A has a charge controller mppt integrated.

[RobinMuric]

Can you tell me how many batteries I need for a 8000 watt inverter? I tried to start up a shallow well 110 water pump but it would not work. I only have 4 rv lead acid batteries in parallel. Do I need more? Thank you.

[tedjelsema]

does battery amps effect pv controllers?

[JD-rpfx]

Is that the required battery sizes if you run the inverter at max power? If your load is only say 200A (a fridge and some lights) you won't place a big draw on the battery, mostly inverter on idle.

[realflow]

I have a super budget cheap universal brand 100 amp hour capacity 12 volt sealed agm lead acid battery paired with a 1000 watt pure sinewave inverter and it works beautifully. No problems. Never took the battery below 80% depth of discharge. and it handles loads like window air conditioners. vacuum cleaners. computers. and more. with no problems. powering it for a few hours.
Doesn't get hot. Voltage drop is not a problem. I used thick 1/0 awg gauge cable so even under the load of a full size window air conditioner it powers it like it's not even there.
It is about 3 years old and still works like new.
I respect the batteries maximum capabilities by checking the manufacturers specifications on it. and it is fully capable of handling anything I throw at it when properly set up and used correctly.
I use it as a backup emergency power generator setup. where it is kept charged and maintained when not in use. and fully charged and ready for use if there is a power outage or other emergency where we need significant portable power. it is very cheap and budget but works great.

[brandonraybern]

400ah lifepo4 with 2000W intverter...should I experience any issues being that much more on my battery bank?

[BenjieEng]

Thanks for this video... I've got the answer to my question 😂