Trident™ Thermal Conductivity Application Highlight Characterizing Performance of a Thermal Adhesive for EV Battery Packs

The following Application Highlight addresses the measurement of both an uncured and cured thermal adhesive material using the Modified Transient Plane Source (MTPS) method in collaboration with HB Fuller. HB Fullers EV Therm 420 is described as a structural acrylic adhesive with excellent thermal conductivity and strength performance properties across a wide range of temperatures and substrates. It is a two-component mixture specified at a 10:1 volume mix ratio. In its uncured state, the material has an open time of 6-9 minutes, fixture time of 15-20 minutes and a room temperature cure time of 24 hours. In its cured state the material is specified to have a thermal conductivity greater than 1.0 W/mK. C-Therm’s MTPS was used to characterize performance in both the uncured and cured states. Due to the mixing requirement of the two-part system, consistency after mixing was assessed over 3 trials. The uncured, freshly mixed material was extruded directly onto the MTPS sensor, and 3 consecutive measurements were taken for each trial (n=3). As shown in figure 2 below, the material exhibited excellent consistency indicating no inhomogeneities were forming during the extrusion/mixing process of the two-components, nor where there any issues related to filler distribution. It should be noted that the curing process had not began to any significant degree during the measurement period.