One big or multiple small batteries?

[Patman923]

Hello all, very new to the forum and trying learn solar stuff!

I was curious if there are any advantages/disadvantages to having multiple smaller batteries or one big battery?
For this scenario we'll say going for 200Ah on a 12V system. Can I have one 200Ah battery or should I have two 100Ah batteries?

 

[snoobler]

Welcome to the forum.

Relative to a big battery:

Advantages to multiple smaller batteries:
Redundancy. One battery fails, you still have limited function with the remainder.
Given that BMS current is a common limiting factor, multiple batteries with lower current BMS add up to higher current that can be easily be obtained with a single high current BMS

Disadvantages:
Sensitive to proper wiring and configuration to ensure current is equally distributed between batteries, but can be done ("Wiring" in link #2 in my signature)