I ordered some copper sheet , 2p nickel plated steel H strip and 21700 insulator rings to day as have decided for the extra cost in total of £7 or so to go with 21700 cells.
For 2p 13s the stand out cell is the moli p42 and out performs the Sam 40T by a bit.
With 2p of moli's at 8.4ah, I can...