Mixing different battery manufactures in parallel - some on canbus connection.

Hi, definitely use bus bar, as for splitting CAN not sure you can do that. I have 5K Solis with CAN connection to two WECO 5K's (master slave) with a 16Kwh Seplos connected to same bus bar, works great although currently don't have the separate rectifier connected to I can charge all three batteries to 100% during the 4hour EV window.

Originally I only had the Seplos connected to the second WECO which seemed ok balance wise but best advice was to use a bus bar.

Inverter is set for WECO so I find when I discharge in the evening once the WECO's reach their discharge soc the Seplos barely discharges, so most of the time never goes to the same discharge soc (which is set same on Seplos BMS), but its only 1-2% different.

Now I haven't tried connecting the Seplos to the inverter and using User defined and letting the WECO's take care of them selves.

I did run just the Seplos for a while to get a couple of charge discharge cycles in and was fine 6%-100%.

As long as the batteries chemistry are same with same number of cells all should be good.

Charge/discharge current is pretty much taken care of by the inverter, I charge at 100amps and discharge 30-100amps depending on how much energy is in the batteries.

Watching on Home Assistant the Seplos will normally be 3/5 of the total current either way.