How to solder energy storage chip capacitor video

Capacitors with nickel barrier terminations, which have a solder coat over the nickel, (or solder coated terminations) are restricted to the reflow temperature of the solder. Temperature cycling causes a change in the mean interatomic spacing of the atoms in the crystal lattice, due to variations in thermal energy.

Capacitors with such terminations will survive molten solder at 260°C with no discernible leaching effect for several minutes versus less than twenty seconds for the best Pd-Ag alloys (since nickel is relatively insoluble in Sn, Pb or Ag and therefore acts as a barrier to solder leaching).

Total immersion in flux and molten solder is attained by pumping them through a fixture to create a constantly flowing crest or “wave” of sufficient height to cover the circuit in its entirety as it is conveyed through. Controlled heating and cooling cycles are required to minimize thermal stresses within the components and bonds.

Solders are the most common bonding alloys used in capacitor attachment. “Low temperature” solders (with flow points under 250°C) are generally tin-lead alloys, with or without silver additions.

Tip1: If a capacitor has long enough leads exposed on the front side of the board, you can cut the capacitor off leaving the old leads and solder the new capacitor to the old leads. This method is even faster. See the last picture for an example. Tip 2: You should replace all the electrolytic capacitors, not just the visibly bad ones.

KEMET Ceramic chip capacitors should be stored in normal working environments. While the chips are quite robust in other environments, solderability will be degraded by exposure to high temperatures, high humidity, corrosive atmospheres, and long-term storage.