Hi, I am going to create a PCB to connect lithium-ion batteries and the parallel groups can reach current spikes up to 60 Amps, now I am wondering how I should place the vias the best way possible (2oz PCB and 18um Via plating)? As even as possible or right behind the connection point with the battery, or where the batteries are connected in series... I really don`t know and would appreciate the help a lot.
Thank you in advance, Jonas

Edit: I have used Saturn PCB, still don't know which diameter is the best and where to place the vias (small 0,3mm vias seem the best but if I want, could I fill them with solder or are they too small?)... I have an area of 30mm width x 70mm length and 30mm width x 140mm length.
I can post pictures if required.