I currently have a 24v system running 2 LifePO4 24v,100ah batteries in parallel. I wanted to add another battery, but noticed it's quite a bit cheaper to get 2 12v, 100ah batteries (same manufacturer) rather than another single 24v 100ah battery. I realize these would need wired in a series and then in parallel with the rest of the bank to be 24v. Looking at the ratings of the 12v batteries, they are exactly half of the 24v batteries I currently have. I assume it's essentially just 2 of those in a case to make the 24v ones I have anyways. Now I know it's generally not recommended to mix batteries, but since these are the same manufacturer and would end up with the same specs running the 2 12v in series, is there any foreseeable issues that would cause a recommendation of not mixing them as I'm considering? Again, I'd like to do this because in the end, its quite a bit cheaper and also allows more versatility/flexibility, should I later change to another voltage. This pic hopefully clarifies what I'm talking about.
