Case Study: Ballard Power Systems eliminates CVM solder-joint failures with ANSYS Multiphysics

Ballard Power Systems - Customer Case Study

Ballard Power Systems, a developer and manufacturer of zero-emission PEM fuel cell stacks, faced intermittent failures in its MK9 series cell voltage monitoring (CVM) assemblies: solder joint breaks in the CVM chips caused false failure signals that could shut down fuel cell engines. To diagnose thermal-expansion–driven stresses from the PCB and potting material, Ballard engaged ANSYS and used ANSYS Multiphysics to investigate the structural and thermal interactions inside the CVM box.

ANSYS performed thermal–structural coupled-field finite element analysis and used advanced submodeling to locate high-stress areas and quantify solder-joint loads; this pinpointed the root cause of failures. Using ANSYS results, Ballard selected a potting material with a coefficient of thermal expansion matching the PCB, which eliminated the bulging effect, reduced peak stress by more than 3X, and verified that CVMs potted with the new material showed no solder-joint failures.

Ballard Power Systems

Kemal Ozgur

Ballard Power Systems