What is the best way to charge multiple individual batteries then combine batteries before going to inverter. Instead of putting the batteries in parallel and losing voltage or in series and losing amperage I want to have 4 or 5 24volt 50ah lithium ion batteries. Equaling 96volt200ah with 4 batteries or 120 volt250ah with 5 batteries. My reasoning is to get the most voltage and amperage from my batteries and to keep the voltage closest to the voltage I'd be using which is 120voltac, so in theory it should be more efficient but maybe more costly.Do they sell combiner boxes post battery bank pre inverter? If a 120 volt dc to 120 volt ac inverter is to hard to find then I'm okay with a 96 volt battery bank equivalent with 96 volt inverter.
120volt battery bank
- Thread starter Sunray
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Or is it wiser to have multiple charge controllers and multiple inverters? My system will be 100% off grid if that helps. I currently have 6 425watt panels at 40volt 10 Amps. My plan was to get a 6 string combiner box to land the 6 panels in. That way I get a incoming of 240voltand60amps. Unless I go the multiple charge controllers route. Depends on advice given here. Thank you
DerpsyDoodler
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How do you expect to you wire 6x 40v 10a panels to achieve 240v 60a?
You have some studying to do. Beware, voltage over 30v can kill.
typically, pv output should go into a solar charge controller (scc), which will convert it to nominal useable output for a 12, 24, or 48 volt system (battery chemistry also need be taken into account when choosing a charger). I feel like you should go back to the drawing board by studying some of Will’s solar blueprints. You can find links at the top of the forum menus (DIY Solar Blueprints). You also need to study up on some electrical basics. Learn what series and parallel mean and how they change the electricity flowing through the circuit.
That alone is not enough to get you up to speed, but at least it’s a start. Remember, electricity is nothing to play with or get complacent when working with. Safety first must always be your philosophy. I strongly urge you to take plenty of time to learn before dropping any money. Ask plenty of questions. People here are knowledgeable and helpful.
You have some studying to do. Beware, voltage over 30v can kill.
typically, pv output should go into a solar charge controller (scc), which will convert it to nominal useable output for a 12, 24, or 48 volt system (battery chemistry also need be taken into account when choosing a charger). I feel like you should go back to the drawing board by studying some of Will’s solar blueprints. You can find links at the top of the forum menus (DIY Solar Blueprints). You also need to study up on some electrical basics. Learn what series and parallel mean and how they change the electricity flowing through the circuit.
That alone is not enough to get you up to speed, but at least it’s a start. Remember, electricity is nothing to play with or get complacent when working with. Safety first must always be your philosophy. I strongly urge you to take plenty of time to learn before dropping any money. Ask plenty of questions. People here are knowledgeable and helpful.
It's simple actual as stated in question. It's called a combiner box (photo below) For example aims sells them. Look up a 6 string combiner box. Then the outgoing of combiner box feeds the charge controller. I'm a certified electrician i understand electricity pretty well I'd say. I'm use to getting zapped with 240voltsac under load. No big deal. Yeah I'm not trying to build the typical 12 -24volt or even 48 volt battery bank. I have the money for a good powerful system. I'd rather not use large cable as would be needed with baby 12 volt systems. Most people dont go higher voltage is because of regulations regarding higher voltage. The typical solar setups your referring to is easy and cheap that anyone can do even if lazy with little skills. Dont get me wrong I have a lot to learn regarding electrical systems.Not arent necessarily the most productive system. I appreciate your reply though. So good ahead and study up! I'm willing to pay for help with my setup.
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They sell 250volt in 250volt out combiner boxes. The aims one is just so you can see the beast yourself
I don’t understand what you are stating here.
4 24V 50Ah batteries in series would be a 96V 50 Ah battery...
when you combine batteries in series, the Ah stays the same. The Wh accumulates series, or parallel, it doesn’t matter...
amps are not lost, watts are not lost.
I am not criticizing, I am trying to understand the question.
Batteries tend to take what they want, so the SAFEST way to charge batteries is in parallel, but that requires massive amps... huge wires, etc... in series, the amperage needed is much lower, to send the same watts, but the imbalance between cells can cause drift, overcharging some, and undercharging others, so a BMS is needed to keep stragglers and leaders from getting destroyed, and equalizing with a balance circuit...
not sure how you would do that with several 24V batteries...
John Frum
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The common system voltages are 12, 24 and 48VDC.
I think you will have a hard time finding system components including solar charge controller, inverter, etc in the range of 120VDC.
Especially for lifepo4.
A 32s or 102.4VDC nominal system could be interesting but I don't know of any components that support this system voltage.
With the popular big blue prismatic cells a battery would weigh ~400 pounds and have capacity of ~29kwh.
Again, here is the problem you are having with desire vs reality.
when you combine panels in series, the volts go up, but the amps stay the same.
when you combine in parallel, the amps go up, and the volts stay the same.
a combiner box is for paralleling strings.
no combiner is needed to series panels... they just clip to each other... but you don’t get amps, AND volts increasing... only one or the other... not both.
6 425 watts panels connected in Series is 240V and 10A
60A is not correct.
Is 40V Vmp?
What is Voc
You would not need a combiner box for series.
In series volts add and amps stay the same.
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To get 240V AND 60 amps, you need 36 panels...
Ok.
What you want is not possible without additional batteries, and additional panels.
Hey, don’t doubt the guy.
electricians deal with panels and wiring... not energy.
DerpsyDoodler
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His very clear lack of understanding may get him hurt or cost him a lot of money.
He just made the mistake of multiplying 6 panels x 10A in a Series array.
He would have. 6 panels at 240V 10A
6 425 watts panels connected in Series is 240V and 10A
60A is not correct.
Is 40V Vmp?
What is Voc
You would not need a combiner box for series.
Just connect the postive to negative of the 6 panels.
In series volts add and amps stay the same.
True! Charge controllers is the easy part. It's the 120voltdc to 120voltdc inverter, and charging seperate battery banks to feed one inverter is where I'm having trouble. Thanks for your reply. Once again I'm willing to pay for blueprint
No... he is here asking how to get what he wants.
It is OUR job to explain, and help... not to argue and attack.
nobody should get upset when asking or receiving assistance.
let’s just be concise with the teaching, and show the mistakes in his request.
I am an electrician, licensed, and have 35years of experience... watts, and batteries fall WAAAAY outside of what we do.
It is possible. Just not in the traditional setups you're probably use to. Mine will cost more and have more components. I've seen 120volt battery banks. I just didnt like there setup, they also used agm
Oh, certainly 120V is possible. Just not the 200Ah part, with only 4 50Ah batteries. To do that, you would need 16 24V 50Ah batteries...
It is simple math. You just have to remember to increase, BOTH amps and volts, you have to increase, series, And Parallel.
I never said it boost them. It combines them together. Thank you
John Frum
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Its not the blueprint you would have to pay for its the research, development and production for an inverter.
Lets say you went with a 32s lifepo4 battery.
A 32s BMS would also be required.
The voltage range is 80VDC to 116.8VDC.
