Electrical Supercooling Mitigation in Erythritol

This report describes an experimental investigation into the effect of electric current in reducing the supercooling of erythritol. Previous studies have identified erythritol as a prime material candidate for moderate temperature thermal energy storage (TES) systems due to its high latent heat of fusion and melting temperature (118°C), but it has also shown excessive supercooling, sometimes exceeding 65°C [1]. Various methods for controlling or reducing supercooling are reviewed, including work by Shichiri and Hozumi showing that a small electric current passed through supercooled water is highly effective in initiating nucleation [2,3]. In the present study, the authors demonstrate a similar effect with erythritol by subjecting a sample to repeated thermal cycles with and without the application of a direct electric current. The control cases without electric current showed a highly variable recrystallization temperature ranging from 67°C to 109°C (or supercooling magnitudes from 9 to 51°C). Passing a direct current through the sample using silver wire electrodes significantly shifted the material’s nucleation behavior. The local nucleation temperature only varied from 108°C to 112°C (or 6–10°C of supercooling), and nucleation always occurred on the positive electrode surface. Control cases both before and after the electrical trials indicated no noticeable change in sample crystallization behavior.