Researchers at Lehigh University, with support from the United States Department of Energy (DOE), have developed a new thermal energy system – Lehigh Thermal Battery – which consists of engineered cementitious materials and thermosiphons in a combination that enables fast and efficient thermal performance at a low cost.

The technology is capable of operating with heat or electricity as the charging energy input.

The project is a collaboration between Lehigh’s Energy Research Center, Lehigh’s Advanced Technology for Large Structural Systems (ATLSS) Engineering Research Center and Advanced Cooling Technologies.

Thermal energy storage is becoming a go-to solution for enabling power grids to respond to variable supply and demand conditions.

Thermal energy storage systems are like batteries that use temperature shifts to store energy for later use or for use at another location.

These systems capture energy in different ways, and the most used techniques are based on latent and sensible heat transfers.

The researchers’ prototype combines the best of both these techniques.

Carlos Romero, a co-principal investigator on the study, said, “The technology offers the potential for adaptation over a broad range of temperatures, heat transfer media, and operating conditions. This makes it suitable for decarbonization opportunities in the industry, the flexibilization of conventional power plants, and advancements and penetration of concentrated solar power.”

The 150-kWhth prototype is a fully instrumented 5ft x 15ft tall structure containing 22 finned thermosyphons.

The prototype has been tested using compressed air at 480°C, producing an energy-to-energy charge/discharge efficiency of the solid media at better than 95%.

The average power rates achieved during charging and discharging were 16.4 and 19.8 kWth, respectively, with a very fast energy gradient of the thermal battery of 0.51 kWhth/min during the first hour of discharge.

The 3-kWhth system, consisting of an electrically charged design, was tested at Dominion Energy’s Mount Storm, which achieved repeatable electrical-to-heat round-trip efficiencies in the mid-70%.

The team said its work could advance the decarbonization of energy-intensive industry, currently responsible for about 30% of all greenhouse gas emissions in the U.S.

Two-thirds of greenhouse gas emissions are generated by the combustion of fossil fuels, leaks, and as by-products of the cement and concrete, iron and steel, chemicals, and the paper and food industry sectors, report the project’s leaders.

Current estimates by the Lehigh team anticipate round-trip efficiencies in the 50% range, and the team has said that after three years of research and development, the technology is both scalable and ready to be commercialized.

Recently, researchers from Stanford University and SLAC National Accelerator Laboratory said they have solved the mystery behind the persistent problem of short-circuit and failure in new lithium metal batteries. The team identified that the problem comes down to nanoscale defects and mechanical stress, especially during potent charging.

In January, researchers at the Daegu Gyeongbuk Institute of Science & Technology said they have developed a new electrolyte technology through magnetic nanoparticles that can improve both the stability and lifespan of next-generation lithium batteries.