Resistance Spot Welding (RSW)

Series Welding – RSW utilizes two electrodes positioned adjacent to each other
but separated by an air gap or other dielectrics. Each electrode contacts the same surface of the base material. This type of welding is utilized where access to both sides of the weld joint is physically restricted or if a component damage Resistance Spot Welding (RSW)would result if the welding current were to shunt through the system circuit or electrical component. Support tooling opposing the force of the electrodes is insulated from the welding circuit and therefore does not shunt current from the welding circuit and therefore does not shut current from the welding circuit.

Resistance spot welding (RSW) - UAV battery packsEach weld cycle produces two fused spots. The electrodes can be positioned parallel or at a fixed angle to each other.

Li-ion cells are comprised of smaller diameter cylindrical steel canisters which are inherently capable of handling greater force from the electrodes. Allowing higher electrode forces aids greatly in ensuring a consistent resistance network for the weld.

 

The configuration in serial and parallel.

The cells terminals are connected by thin nickel busbar (with 99,97% purity) through RSW (Resistance Spot Welding), according to the configuration needed.

In the series connection and the positive/negative terminals of the battery pack are reinforced to sustain high flow current. Strips in parallel can have a melting link (cell level fuse) or not.

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32P battery unit engineered with 20A fusible section on nickel stripe at the cell terminals, all connected to 1 mm thickness main busbar.