Aligning jig for spot welding two 18650 Lithium cells in parallel

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I had already designed an aligning tool which worked but it was not very practical in use, so I made this new version: When paralleling 18650 Lithium ion cells by spot welding, it is often challenging to get the nickel strips straight and to precisely hit the poles with the spot welder, especially the smaller plus poles. This aligning tool is for paralleling two 18650 cells with 7mm wide nickel strip. How to use: Insert the batteries and nickel strip into the adapter, plus poles on the side with the smaller opening, minus poles at the larger one. There are two slots for using rubber bands to hold the cells at the bottom if necessary. Spot weld through the openings, then remove your paralleled pack from the jig. The openings at the bottom can be used for pushing them out. IMPORTANT NOTE: Before you start, be sure to measure the voltage on both batteries, there should be no more than 0.1V difference in voltage. Charge/discharge them to reach the same voltage before connecting them in parallel.