Wevo Introduces Silicone Gap Filler for Tight Battery Pack Spaces
The WEVOSIL 26040 FL is designed for bondlines under 70 micrometers in compact EV battery and electronics assemblies.
German adhesives manufacturer Wevo-Chemie has launched a new thermally conductive silicone gap filler aimed at high-voltage battery packs and power electronics with tight spacing constraints.
What Happened
The company introduced the WEVOSIL 26040 FL, which is rated at 4 W/m·K thermal conductivity with a density of 2.22 g/cm³. According to Wevo, conventional paste-like gap fillers with high viscosity become difficult to apply when gaps measure only a few millimeters. The new material can be applied at bondlines of less than 70 micrometers and is designed for reliable use in compact assemblies. It can be laid down as a bead and compressed under low pressure or injected into gaps, and the company states its sag resistance prevents it from flowing back out. Wevo says the formulation works with standard dosing systems such as piston and eccentric screw pumps, avoiding the need for specialized extruders and barrel extrusion stations required by many highly filled alternatives. The material cures without by-products or volume shrinkage.
Why It Matters
For EV battery pack designers, thermal management in densely packed assemblies remains a persistent challenge. Wevo says the gap filler can support weight-optimized designs due to its lower density compared to comparable thermally conductive materials. The company states it is suitable for thermally bonding compact high-performance batteries and electronic components to outer skins in narrow areas with layers of 1 to 2 mm, supporting rapid and uniform heat dissipation. The material's compatibility with standard dosing equipment may lower adoption barriers for manufacturers already using similar systems for potting compounds.
The Bottom Line
Wevo-Chemie is targeting the EV battery thermal interface market with a gap filler designed for sub-millimeter-scale gaps in compact assemblies. Applications include batteries for electric vehicles and industrial environments, as well as power electronics components.
