RE: Big Scale with A123 power
The cells are not soldered or welded. They are held to the 3" PVC pipe base by the bar across the top of 2 cells in each bank that serves as the electrical connection between the two. The bar is clamped to the pipe with a screw that screws into a five fingered 1/4" plywood base mounted on the pipe. Electrical connection from bank to bank is provided by sheet brass glued to the pipe at the apropriate places.
The cells are also stuck to the five fingers with double stick carpet tape and the two cell bank is covered with 95mm heat shrink tubing.
There are two dummy cells. (1 in dowell) The motor is limited to 8 cells by the voltage limitation of the ESC
I have about 25 flights on the motor in a 62" Lazy Ace.
I usually fly about 3 min. but the recharge at 3A is only 30 min so I could fly at least 5 min.