Soldering flux for energy storage batteries

Are selective soldering fluxes reliable?

The reliability of the fluxes designed for the selective soldering application was assessed using well known industry standards, where the flux was subjected to various thermal conditioning conditions (Table 1).

Why is surface energy important for selective soldering fluxes?

Finally, the surface energy of the solder mask is another critical parameter: lower surface Energies are favored for selective soldering fluxes compared to conventional wave soldering fluxes (35mN/m vs >50mN/m) to increase the contact angle of the flux on the substrate.

How does thermal history affect the performance of selective soldering machines?

In this application, thermal history of the flux residues (from room temperature to solder liquidus) is a key performance driver. Finally, it is necessary to conduct statistically designed experiments on industrial selective soldering machines in order to map the relationships between flux characteristics and selective process friendliness.

How are batteries soldered?

But also for industrial productions, batteries are soldered as for example the battery modules of the full electric MINI E by the BMW AG . In principal, soldering and brazing are based on a joining process where the joining partners are connected by melting and putting a filler metal, the solder, into the joint , .

Are water soluble fluxes good for soldering?

Water Soluble fluxes are excellent for soldering, and provide the best soldering possible. They have a great amount of activity that readily cleans the metals to be soldered, and virtually never burn off during the soldering process.

What is soldering & brazing a battery cell?

As defined by the American Welding Society, soldering is done with solders that melt below 450 °C and brazing with solders melting above this temperature . For battery cells the heat input of the connection process has to be relatively low to not damage the battery cell’s internal electrochemical components.