[joe_db]

Originally Posted by edwardc

Neil,

I must admit that this is one of the thoughts that weighs heavily on my mind during this planning process. As Joe pointed out, I'm trying to design as redundant a system as possible. The better option might be two independent, paralleled banks with two separate BMSs, but this would get more expensive. Re-configuring underway from a 2P4S configuration to a 1P4S configuration would suck but would be possible.

As for unavailability of stuff in the Exumas, I'm already in that "boat" Gel Cells are also impossible to source in the Bahamas. Hell, they're difficult to source in the US!

My ultimate fallback would be to temporarily replace them with a pair of cheap flooded Lead-Acid batteries. The highly programmable charge controllers would have no trouble accommodating that.

Before our first trip, I thought long and hard about what engine spares to bring. There isn't enough space to bring everything, so I tried to confine myself to critical things I couldn't repair. This included a spare alternator (with its own regulator), a spare starter, and a spare EI module.

Most commercially available lithium batteries can be connected in parallel, I don't see any reason you can't make two batteries with two BMSs. Speaking of, are you SURE you have a good source for cells? I looked into that and it seems a crapshoot at best, apparently almost all cells are rejects that Renogy and the rest of the battery companies didn't want.