I know I saw it somewhere lol

[myersfamilyhome]

So I'm reevaluating going 48v because I believe I had seen it somewhere that it is possible to build a large stable balanced charge/draw 12v battery bank (for example 24 12v deep cycle 100ah batteries in parallel) if it's designed right. 48v sounds great but though I have funds to build the initial setup right now for either, in 2 years from now when a deep cycle battery goes out my available power is impacted much more because it pulls a whole series (400ah) out of service until the 1 battery is replaced. In a 12v bank I'm only out that one battery (100ah). I'm aware of some of the common limitations to my build but the one I cannot figure out is even draw and charge of all the batteries.

If I have multiple charge controllers (because they are limited to how much they can handle at a 12v config), could I have a negative and positive copper bus bar that the charge controllers, and the inverter connect to, and instead of connecting the batteries in parallel to each other I use the same guage and length wire to connect each battery separately to the positive and negative bus bar?

 

[snoobler]

Welcome to the forum.

Your proposed solution is essentially ideal. See "Wiring" in link #2 in my signature. That Victron resource details the best practices for connecting batteries.

12V may drastically limit you on total power output. For 3000W, you'll have to push 250A to drive it. 3000W is generally the upper limit for using 12V.

24V may be a better option as you'd only lose 100Ah @ 24V (2400Wh) instead of the 100Ah @ 48V (4800Wh).

 

[MichaelK]

I can not understand why some people cling so desperately to 12V as if it was a Commandment from God? I will never go back to 12V for anything that is not on wheels. Build your 48V system and be happy! Why jump through so many hoops just to make 12V work, when there are better solutions right in front of you?

 

[myersfamilyhome]

I can not understand why some people cling so desperately to 12V as if it was a Commandment from God? I will never go back to 12V for anything that is not on wheels. Build your 48V system and be happy! Why jump through so many hoops just to make 12V work, when there are better solutions right in front of you

Better is all a matter of interpretation and need.

I don't need more than 3000w.
I want piece of mind knowing that 20 years down the road it can be easily understood, repaired, and maintained without any issue. Be able to readily find resources as needed. No dependency on waiting for it to be shipped, or have my system down quarter power because of a bad battery.

I'm fully aware there are many ways to skin this cat. I was asking because I am seeking knowledge so I can determine what's best for me. Every installation and its purpose has an ideal design.

 

[MichaelK]

Then why do you need 24 12v deep cycle 100ah batteries in parallel?

 

[myersfamilyhome]

Then why do you need 24 12v deep cycle 100ah batteries in parallel

"for example" does not mean "I need" or "I have". It helps define an understanding of intent.