If this tiny bank can source 70 amps (1800w) with little voltage drop, can you imagine how much current you could pull from that bank without heat? 500A 26kw surge wouldnt even dip voltage. Your setup is far stronger than any grid supply.
I have 200A fuses on it (actually, 200A fuse on the 600AH pack, and another 200A fuse on the 300AH pack) - they tend to share current pretty nicely so far, about 2/3 of the amps to/from the 600AH pack and the rest from the old 300AH pack.
So I dare say I could easily pull 300A with it as it stands, but that's far more than I ever need or use.
And yes, it doesn't sag or drop so far I'm absolutely wrapped with them all.
GBS is a good battery but there are several to choose from how did you decide which brand to go
with?
In the end, when I simply could not get the same as my original bank, I went with a combination of:
* who had cells of the right physical dimensions to suit the space I had
* who was most responsive to my emails
* who seemed most technically competent, able to converse in english and sounded like they had some clue
* who offered the best price (consistent with all the above)
These are rated for 2000 cycles (im probably nearing that now) and i know of another review of these cells that shows degradation at 3 years. Yet some are claiming 20+ years. How many years are you expecting to get out of yours?
Most of the LFP cells seem to quote around that 2000-3000 cycles "useful life" (they don't die then, they're just down to 70% to 80% of original capacity). I was hitting my old bank pretty hard and I'd say I've probably taken something close to the equivalent of 800 cycles from them. By adding a decent chunk of extra capacity, and expecting only a modest increase in demand, I fully expect to get 15+ years out of this lot now, and won't be surprised if I get a lot more.
Defenitely a good battery technology, the price justification is in the performance and longevity calculations.
And the space savings, and the weight savings, and the elimination of potentially explosive gas and corrosive fumes, and the inevitable liability of "toxic waste" of all that lead in years to come. (I'm going to go out on a limb here, and say that right now, today, you can sell your old batteries and get 50-60c/Kg for them - in years to come, you'll be paying several dollars/Kg in "safe disposal" fees to dispose of them... factor THAT into your lead-acid storage equation!)
LFP are basically "completely maintenance free". Put decent continuous balancers on them, and some sort of monitoring so you can spot a problem early (I haven't had any on any of mine, but it's still comforting to know), and never have to touch them again.