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SOK batteries

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if i had 500 watt solar system with a 40A MPPT charge controller, would it be better to have 1 or 2 SOK 12v 100 ah batteries or have 1 SOK 12v 206ah battery ?
 
None of the following is specific to SOK batteries or your use of that SCC and your panel choice:

1 battery doesn't require any care to keep it balanced so that's simpler than setting up two batteries in parallel.

1 battery is simpler and cheaper due to less wiring.

2 batteries has the very slight advantage that if one battery goes bad, you can at least keep running on the remaining battery. I say it's a very slight advantage because it's unlikely a battery will go bad unless you abuse it through bad charge settings.

A few minor things specific to those SOK batteries:

The 1 206Ah battery has slightly more capacity than the 200Ah from the 2 100Ah batteries.

The 1 206Ah battery is cheaper ($1029) than two 100Ah batteries ($1140).
 
in fact, it depends on your inverter, if the inverter under 2000w, i suggest just one 206Ah, if 2000W~3000w, i would suggest you get 2 100Ah.
 
this is very helpful, could you explain why this is the case?
Both the 12V 100Ah and the 12V 206Ah SOK batteries have a max continuous discharge capacity of 100A, and a peak of 200A for 3 seconds. Two of the batteries in parallel double that to 200A continuous and 400A peak.

In a 12V system a 2000W inverter needs 167A. A 3000W inverter need 250A. Given these numbers, I'm not sure why Min suggests a single battery for a 2000W inverter since you need 167A which is obviously well above the rated 100A continuous.

Another option is to go to 24V. At 24V a 2000W inverter only needs 83A and a 3000W inverter needs 125A.
 
Thank you for the reply, very helpful to understand this.

So if we put this into practice, on a 24v 2.4kw (like the 2424) system a good , but close to max, solution would be two 12v Sok 100AH in series, which would keep the batteries at 100A continuous (series v parallel). Series being better for battery health long term v parallel? But a better solution would be 1 206Ah 12v Sok, best being 2 206ah 12v Sok?
 
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So if we put this into practice, on a 24v 2.4kw (like the 2424) system a good , but close to max, solution would be two 12v Sok 100AH in series, which would keep the batteries at 100A continuous (series v parallel).
For a 24V inverter you need two batteries in series to get 24V. A 2.4kW inverter at 24V is 101A. So it's fine to have either 2 100Ah or 2 206Ah SOK batteries in series since the two in series gives 24V and you get 100A continuous discharge with the batteries. You could put 4 100Ah or 4 206Ah in 2S2P if you needed 24V and you wanted more storage. You also happen to get twice the discharge amps due to the 2P aspect but it's not needed in this case. It just gives you twice the storage of just 2 batteries.

Series being better for battery health long term v parallel?
Don't think about series or parallel being better for battery health. You put batteries in series when you need higher volts. You put batteries in parallel when you need more amps. You can combine both when you need both more volts and more amps.

But a better solution would be 1 206Ah 12v Sok, best being 2 206ah 12v Sok?
You need 24V for the 24V inverter so you can't use just one 12V battery regardless of its capacity. You either need a 24V battery or you put 2 12V batteries in series. You can choose 2 100Ah or 2 206Ah based on how much capacity you need.
 
when i started this post i didnt and still dont know much about solar but i got 400 watt 12 volt solar premium kit from renogy and a 12v 206ah LiFePO4 Lithium Iron Phosphate bettery from SOK but went with a 3000 watt inverter
and i ALWAYS keep an eye on it but it never says battery over disc times or never says battery full charge times
when i wake up before the sun comes up i check what it says and on the renogy app it says about Battery volts 13.00 and Capacity is about 95%

is this good or bad ? lol
 
With 400 Watts of solar you are best off with one battery NOT two. It’s going to take a while to charge two batteries unless you purchase more panels. Get a 100 Amp fuse or breaker for between your inverter and battery and don’t ever plan on using more than 1000 Watts from that inverter until you purchase a second battery as well as more panels. Use what you have and use it the way it is until you can learn your limitations and understand what you currently have. You’ve got a good start but there is a little bit of a mismatch going on because of the inverter. You can certainly work with what you have as long as you don’t try to pull more than 100 Amps from that single battery.
As far as your latest question, you need to specify what your charge parameters are set up for before someone can give you a specific answer to that one.
I’d say that you need to read up on some of the Beginners Circle thread.
Here is a good read to start with: https://www.solacity.com/how-to-keep-lifepo4-lithium-ion-batteries-happy/
 
in fact, it depends on your inverter, if the inverter under 2000w, i suggest just one 206Ah, if 2000W~3000w, i would suggest you get 2 100Ah.
min is off a bit
Why?
You stated your inverter is 3000w. Your potential draw could be 3000w/12v = 250a (+ extra for inverter inefficiency)
a single SOK can't handle that load, even 2 would be pushing the batteries past their stated limits of 100a discharge

(properly) wired in parallel the batteries would share both charging and load currents.
The numbers suggest 3 batteries in parallel at 12v, 3000w load

Now if your actual use/load is less, say 2000w a pair of batteries would suffice
2000/12 = 167a /2 = 83a which is a nice sweet spot that doesn't push the batteries hard

as already said, 400w of panels isn't enough to keep the battery(s) charged if you're drawing such loads
400w charging can't keep up with a 3000w load
say your load is only 1000w, it would only take a bit over 2 hours to deplete the battery
206ah battery x 12v = 2472Wh/1000w = 2.47 hours
..with a 3000w load you won't even get an hour
400w of PV would take a bit over 6 hours to replace that load.
going with higher loads makes it even more unbalanced

on another note, it's not required to fully charge a LiFePo4 battery (80 to 90 % appears to be the consensus opinion)
lower charge levels won't hurt the LFP battery as in the case of La
 
you ALL lost me at ..... well just lost .. I'm sorry but i dont understand this 3000w 2000w 1000w .. when you start throwing numbers at me i get lost.

this is the beginners corner and only thing i know is im running 400watt solar to my 40a charger thats charging my 206ah battery thats running my 3000watt inverter and in turn its keeping my small fridge running and a house after the sun comes up i check on my app for renagy and it says 100% and its about 14volt
 
Not how much simpler I could have been. It might be time to buy Wills book and learn some basics. If you don’t understand what you have, then I suggest you might not want to use it for fear of ruining it. Im not sure if there was a question in your last comment to help you become a little less lost. Was there?
 
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