How to Select Potting Compounds for OBC? Thermally Conductive Potting Solutions for On‑Board Charger Inductors, PCBs and Power Modules

Thermal conductivity is far from the sole criterion for selecting potting materials for new‑energy‑vehicle OBC systems. Inside an on‑board charger coexist power devices, inductors, transformers, PCBs and high‑voltage connection zones. Different locations impose divergent requirements for thermal conduction, electrical insulation, flame retardancy, stress performance and flowability. For OBC modules requiring low‑stress full potting, ELAPLUS SIPA 1850 series thermally‑conductive silicone potting compounds are recommended for evaluation. For constructions calling for a balance of flexibility and thermal performance, PUR 1680 thermally‑conductive polyurethane potting compound can be considered. For assemblies demanding high‑temperature performance and superior dimensional stability, EP 1710 epoxy potting system may be assessed according to design specifications. These represent the core principles for OBC electronic adhesive selection:First define heat sources and heat dissipation paths to determine the required thermal conductivity; identify stress‑sensitive components and structural constraints to specify the target hardness of the potting material. Why Do OBC Units Require Potting Compounds? An On‑Board Charger (OBC) converts alternating current into direct current for vehicle traction battery packs.As new‑energy‑vehicle high‑voltage platforms evolve and power density rises, OBC internal housings become increasingly compact, leading to concentrated heat buildup across power devices, inductors and high‑voltage circuits. Typical field challenges include:‑ Heat generation from inductors and transformers‑ PCBs enduring repeated thermal cycling‑ Vehicle‑borne vibration transmitted directly to solder joints‑ Moisture ingress risks within high‑voltage regions‑ Build‑up of internal stress in large‑volume potting sections‑ Interfacial thermal resistance between power components and metal housings OBC potting is therefore not a simple process of pouring resin into an enclosure.Its core objectives are multi‑fold: thermal dissipation, electrical insulation, vibration resistance, moisture protection and thermal‑stress buffering. Recommended Potting Compounds for Full‑Volume Thermally‑Conductive OBC Potting ELAPLUS SIPA 1850 Potting for Inductors For OBC assemblies needing low‑stress protection, the two‑component thermally‑conductive silicone potting compound SIPA 1850 series is a prime candidate.Upon cure, this silicone‑based material retains elastic…