Hokkaido University Research Profiles


High-temperature Latent Heat Storage Microcapsules

Core (alloy latent heat storage material) ? shell (Al2O3) type latent heat storage microcapsules capable of high-density heat storage in the high temperature range of over 500?C

The latent heat storage method, which utilizes latent heat generated during the solid-liquid phase change, is attractive for its high-density heat storage capacity. Microencapsulation of latent heat storage material enables not only heat storage but also heat transport and heat control applications, and we have developed latent heat storage microcapsules that can be used in the high temperature range of over 500°C.

Content of research

An Al-base alloy with a melting point above 500°C was newly discovered as a latent heat storage material. By skillfully applying chemical conversion/oxidation treatment to the micro-particles of this alloy (approx. 20 μm or larger), we have succeeded in developing core (Al-base alloy) and shell (Al2O3) type latent heat storage microcapsules (Fig. 1). These microcapsules have high heat storage capacity of approximately five times that of solid sensible heat storage materials, and have excellent mechanical properties. Since the shell is made of Al2O3, it can also be treated as a ceramic particle. In other words, it is an epoch-making heat storage material of which the performance can be upgraded while maintaining the current use of ceramic sensible heat storage technology.

Potential for social implementation

  • ・Industrial waste heat recovery
  • ・Thermal storage system for solar thermal power generation
  • ・High heat capacity heat transport medium
  • ・Microreactor

Appealing points to industry and local governments

Using the developed high-temperature latent heat storage microcapsules as a key material, it is expected to establish a new foundation for heat storage, heat transport, and heat control technology in the high-temperature region (Fig. 2). In the future, we plan to develop innovative heat utilization devices, regardless of their application to energy conservation or new energy.

Intellectual property related to this research

(日本:特願2016-514724 米国:15/305950 欧州:15782845.0)