18650 Cell Connections for ebike Triangle Battery Pack?

[markisses]

I'm attempting to construct a 11P13S triangle battery pack (w/ BMS) out of 18650 Li-ion laptop cells. This will be connected to a 48V 750W BBS02 (25A current limit).

In the diagram above:
-Each number is an 11P unit that will be spot welded together with 8mm X 0.15mm Pure Ni Plate Nickel Strip.
-Red is the positive and Black is the negative terminals of each unit.
-The orange arrows show the order that each unit will be connected to each other (the order they will be connected in series).
-A dotted line represents a connection below the pack.
-The magenta lines are the connections between each unit (made with 8mm X 0.15mm Pure Ni Plate Nickel Strip).
-An insulating material will be placed between units, represented by the green lines.
-All the positive terminals of each 18650 will have a gasket (from FastTech).

Questions:
-Are there enough connections between each numbered unit for the series connections?
-If there is not enough connections, what are my options? (I assume, I could always double or triple the nickel strip between each unit.)
-Are there any flaws with the pack design?
-What are some recommendations for making the pack safer, more functional, or generally better?

 

[markisses]

What kind of copper - wire, braided, flat?
Do you have a source for the copper?

 

[9lives]

What kind of copper - wire, braided, flat?
Do you have a source for the copper?

Markisses, I stuffed around with copper plate but found some electrical cable in the hardware shop that had 2mm solid copper wire in it. The wire soldered much easier than plate and minimised heat going into cells. The cable is the high amp type they wire houses with (at least here in Australia) Active and neutral had the solid wire and the ground has finner copper cable which is great for joining cables. You can tell it had solid copper by how hard it is to bend.

If you are building a low amp pack I'd recommend spot welded nickel tabs as it is much easier. I only doubled up with copper and it was time consuming compared to spot welding.