Bringing Solder Paste Reliability to E-Mobility
By Claire Hotvedt, Indium
It’s not just about fun and helpful infotainment systems; next generation vehicles have power inverters and battery management systems that demand incredible reliability to keep the vehicle running and passengers safe. eMobility technology is a complex puzzle, and solder paste may be just one piece, but it’s one we cannot overlook. In every electric vehicle, circuit boards are controlling the components and systems necessary for operation, and solder paste is holding them together.
What are we paying attention to in regards to lifetime solder paste reliability and safety in electric vehicles?
- Electric vehicles require electrical reliability. There is enhanced testing available for solder paste fluxes to avoid current leakage or other serious concerns with small fine-pitched components and patterns in different environments and voltage conditions.
- Components handling high current and voltage (inverters anyone?) also handle areas with high heat. Solder alloys are not just a conduit for current but also need to handle the heat.
- Speaking of solder alloys and heat – the mechanical stresses from thermal expansion and cooling add up over a vehicle’s lifetime.
Before a vehicle gets to demonstrate its lifetime performance, solder paste materials science is essential for achieving reliability during circuit board manufacturing. Solder paste that is implemented well prevents defects:
- When unchecked, certain material characteristics like warpage during reflow can start causing real challenges. The Non-Wet-Open (NWO) defect, in which all the solder paste has been lifted off the PCB by warpage, is a growing issue. Fluxes with higher activity or oxidation barriers can help avoid NWO-driven open circuits.
- When ensuring flux compatibility with a given process, some process conditions are more unique than others. Vacuum reflow enables ultra-low voiding – but to get there without solder spatter and splash, both the process and the paste must be taken into account.
An electric vehicle is a massive, ultra-reliable system of interconnected computers. At Indium Corporation, we understand the high reliability needs of cars, electrification, and computing. Solder paste is a key component to achieve that reliability. Reach out to me or any of our global Indium Corporation team for solder paste or printed circuit board assembly advice and support.