Rapid temperature transients sustained during the operation of high-voltage electronics can be difficult to manage by relying solely on uniform heat removal mechanisms. Phase-change materials (PCMs) can be useful as a buffer against these intermittent temperature spikes when integrated into electronic packages. However, their integration poses challenges of both physical and electrical interactions within the package, particularly in high-voltage systems. This study aims to evaluate electrical and thermal properties of nano-enhanced PCMs to inform their integration in high-voltage systems. The nanocomposites are obtained by seeding 3 × 10−5 and 3 × 10−4 wt % of gold and iron oxide particles to sorbitol. Improvements in thermal properties including thermal conductivity as high as 8% are observed; however, this comes at the expense of the dielectric strength of the PCM. Additionally, an implementation scheme for the nano-enhanced PCMs in a high-voltage-capable power module is proposed with accompanying computational and experimental performance data.