Aligning jig for spot welding two 18650 Lithium cells in parallel

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I had already created a precise aligning tool which worked but it was not very efficient in use, so I developed this new version: When pairing 18650 Lithium ion cells by spot welding, it is often difficult to get the nickel strips straight and to accurately hit the poles with the spot welder, especially the smaller plus poles. This aligning tool is designed for pairing 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 paired pack from the jig. The openings at the bottom can be used for pushing them out. IMPORTANT NOTE: Before you start, make 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.