There are many useable batteries that die an early death by being part of a pack where one cell dies. I have scavenged many of these packs and tested each cell, keeping those at 80-90% and have bought battery plastic carcasses for my power tools that have enable me to save a fair amount of $$ over the years. These were all spot welded cells. This indiegogo has cell mounts like flashlight, and cells are pushed into cell sockets and seem to make spring connections. As long as these spring connections are low resistance for the anticipated 5-10 Amp current = excellent idea. I would like similar cell carcasses for all common power tools to be made this way? I suspect battery sales are make lots of $$ for tool makers. The carcasses from Ali-Express use spot welded connections, but ali also sold me a spot welder and nickel straps for this use,