Let's address a few things first so communication is clear.
A Battery bank is a set of Batteries set into either series/parallel or combo thereof. A Battery Pack is a complete independent battery and one places multiple packs into a "bank". Batteries in Series increase Voltage, Batteries in Parallel increase Stored Energy (AH). Battery Packs in Parallel Divide & Share both Load & Charge proportionately*.
Unlike Lead Acid battery variants, you can add LFP packs in parallel at any time without negative consequences. With Lead, the weakest battery drags down the rest, this is not teh case with LFP due to teh management systems and the very flat voltage curve. You can even have 100AH, 200AH & 300AH Battery packs within a Bank without issues (albeit some careful math is required during design & implementation). Note that if using different AH packs, the EndAmps/Tailcurrent Calculations have to be adjusted. Also with Different AH Packs the way they Charge & Discharge is proprotionate to their capacity.
Battery Packs that have SmartBMS' that interconnect & communicate with the Inverter does change the picture somewhat. Generally, it is best to stick with Same Brand & Similar Model of Battery/BMS to ensure that it works. There are several BMS' in se which can interconnect & communicate BUT they are not all compatible with each other... There are no default set Communications Standards or Protocols as yet for this particular sector.
Below is a Generic Template for an AIO (All-In-One) based system... which includes Solar Controller/Inverter/Charger in one unit. This shows 3-AIO's in Parallel but it is the same for 1-AIO just eliminate the upper pair of bars.
Each pack uses an Identical Length Same Gauge wire from Pack to Busbar.
The Fuse is in-between and not calculated for length difference. Up to 36V you can use MRBF, after 36V, use of Class-T or MEGA fuses. For a 100AH Battery a 150A Fuse is appropriate.
NOTE - WARNING !
Not ALL Busbars are equal and the cheapo's out there WILL burn your house down ! I Very Strongly urge you to buy only Quality Busbars from Bluesea, Victron, Pike Industries and so on.... AVOID those cheaper "pairs" on Ebay/amazon.