Resistance welding: new technology for the lowest possible contact resistance

The specialist in connectors and electromechanical contact solutions, Yamaichi Electronics, is using the relatively new technology of resistance welding in its Frankfurt (Oder) plant to implement perfect contacts with the lowest possible contact resistance for customers with special requirements. This technology is used in Yamaichi´s “hermetic sealed” photovoltaic junction boxes for solar panels, among other places.

As an innovative provider of technical solutions in the area of electrical connections, Yamaichi’s products and machining processes must always correspond to the latest state of the art. Yamaichi Electronics is therefore always expanding its palette of processing technologies and products. This permits fast, flexible reactions to customer needs. With their many years of experience and technically ideally equipped fabrication facilities in Germany, Yamaichi is thus a very reliable partner.

The resistance welding process is a relatively new technology, but one seeing ever more frequent use. It permits contacting to be made without additional material such as solder or contacts. That reduces contact resistance and prevents corrosion.

Fully automated processing of large lot sizes

Wires are cut fully automatically, their insulation stripped and inserted into the compacting unit. Large lots can be produced fully automatically with no problems.

Flexible fabrication of small lots

A manual compactor that can be used flexibly also permits the fabrication of customer-specific small lots with very low costs in terms of time and investment. Cut and stripped wires are fed manually in this process.

The resistance welding process

After insertion of the prepared wires into the compacting unit, the lateral ceramics move into their end position, defining the width of the compaction. The electrodes then press the wires together and electricity is applied after a defined setting period. During the subsequent cooling phase, the pressure is maintained in order to avoid the formation of pores.

Process monitoring

For monitoring of the welding process, the values and progress over time of the following parameters can be evaluated:

  • Welding current
  • Welding voltage
  • Electrode force
  • Electrode penetration distance

Process documentation is simultaneously possible.

Advantages of the technology

Resistance welding offers advantages in the fabrication process and in the technical implementation of the contact. The contact characteristics are improved due to:

  • The gas-tight connection
  • Reduction of corrosion
  • Lower contact resistances
  • Different shapes possible
  • Many options for additional contacts, such as hard and soft soldering, screw terminals, welding with various contacts.

The fabrication process is optimised due to:

  • Completely amenable to automation
  • Flexible degree of automation that also permits small series
  • Reproducibility with measurable, documentable parameters

Yamaichi Electronics uses this technology in its hermetic-sealed photovoltaic junction boxes for solar modules, among other places. With its considerable experience in numerous customer projects and the know-how in resistance welding it has obtained during those projects, the manufacturer confirms its role as a competent technology leader and project partner.

Additional information about this technology can be obtained by sending an email to