Inspection of laser welded electrical connections for car batteries using eddy currents
The market for Electric Vehicles and Hybrid Electric Vehicles is growing rapidly, and, with this, the demand for electric batteries is growing too. Lithium ion batteries require several stages of construction, with one particular stage requiring the joining of highly conductive aluminium (or copper) busbars to the electrode cell ends of the battery. Laser welding has been considered for replacing the current mechanical screwing joining technique, which is considered too slow and produces too many imperfections. The cumulative aluminium weld area determines the electrical conductivity of the connection, and as such, the performance of the device. Laser welding offers the advantage of high speed, low heat input and lowdistortion compared with more conventional resistance spot or TIG welding processes.