Innovation Sphere



Project TitleClay-Ionic Liquid Electrolytes for High Temperature Energy Storage
Track Code2012-063
Short Description
Tagsbattery, lithium ion, electrolyte, High-Temperature, clay, capacitor
Posted DateMay 25, 2016 10:34 AM


At high temperatures the electrolyte material used in most batteries and energy storage devices breaks down, greatly decreasing battery efficiency, preventing the transfer of charged ions, and possibly resulting in catastrophic failure. Additionally, the separator that electrically isolates the battery cathode and anode can deform at high temperatures causing breakdown of the battery. In order for batteries to be operable at elevated temperatures, specialized heat shielding is often used, greatly adding to the size and weight of the device, and reducing usability. New materials with enhanced thermal stability are greatly needed to expand the operating conditions for energy storage devices.


One such material discovered by researchers at Rice University is a Bentonite clay - ionic liquid electrolyte. This novel composite material consists of a tailored ratio of Bentonite clay and a room temperature ionic liquid (RTIL) consisting of various molten salts. Suitable molten salts are chosen based on the cation size and the clay properties while the clay – RTIL weight ratios are optimized for uniform dispersion and temperature stability.  

Benefits and Features

  • The Bentonite clay-based electrolyte achieves better high temperature performance and shows demonstrated stability at 200°C
  • Two order of magnitude increase in power density at 200°C compared to room temperature
  • Stability has been demonstrated over thousands of charge and discharge cycles at elevated temperatures

Market Potential / Applications

A potential market for this technology could be the oil and gas industry where devices are routinely exposed to high temperature operating conditions. In these harsh environments with elevated temperatures the operating life of batteries is greatly reduced and battery breakdown can occur. To avoid this, many devices are engineered to have large amounts of shielding or insulation to limit the exposure of the battery to the external environment. This not only adds cost but it also increases the size and weight of devices, which may limit their usability in the field. Another market that could be envisioned is in medical environments where sterilization of devices is often employed before use with each patient. A battery capable of operating at high temperatures could be sterilized with the rest of the device or instrument, rather than being detached.

Development and Licensing Status

Patent pending; available for licensing from Rice University. Tested at the laboratory scale.

Rice Researcher

Pulickel Ajayan is the Benjamin M. and Mary Greenwood Anderson Professor in Engineering at Rice University.

Technology Relevant Papers and Web Links

“Clay key to high-temperature supercapacitors,”


R. S. Borges, A. L. M. Reddy, M. T. F. Rodrigues, H. Gullapalli, K. Balakrishnan, G. G. Silva, and P. M. Ajayan, “Supercapacitor Operating at 200 Degrees Celsius”, Scientific Reports, 3 (2013);

Case #


Inquiries to:

Andy Gapin,, (713) 348-6272