Okay, so thats good that you used silicone wire as a flex point.
This guy pavel is using a bit of antiquated method. Ideally, you solder to nickel and then spot weld it to the cells. This reduces the amount of heat going into the cell. The better you are at soldering and the more powerful your iron is; the less of an issue this is.
So just keep that in mind. Consider following this thread and picking up some of the latest and greatest in battery building technique.
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