Believe it or not, Busbars are a simple thing yet there are sheisters out there flogging crud which can cause issues.
There are different kinds of Busbars... Those for interconnecting cells, those for inter-connecting battery packs & DC Equipment.
Use ONLY DC Rated Equipment for DC Systems ! Busbars for cells are usually supplied by Vendors/Suppliers providing the cells. Many of us do make our own cell busbars from Aluminium or Copper flat stock as well.
NB:
- It is suggested to use Busbars which have protective covers which can certainly help prevent an accidental short.
- Always make sure the busbar selected can handle the Maximum Amperage Demand possible from the system including Max Surge the Inverter can demand. So if you have a 4000W Inverter that can handle a 12,000W Surge, busbar should handle 12,000W÷Volts = AMPS