Thermal batteries put the “sun in a box”. They allow solar/renewable energy to be stored and used at night or whenever there’s demand.


Thermal batteries are thermal storage and conversion systems that serve the function of grid scale rechargeable batteries. A thermal battery takes in electricity from the grid, and supplies electricity back to the grid whenever needed (i.e., with a roundtrip efficiency targeted at 50%).

Low Cost

Thermal battery costs are projected to be less than $20/kWh-e and $0.35/W-e.


Thermal batteries are cost effective at scales as small as 50 MWh with a 10 MW discharge rate, and become increasingly cost effective at larger scales.


The system is highly flexible and configurable for specific applications, since the charging rate, discharging rate and amount of energy stored are essentially independent.

Long Life

Thermal batteries are engineered to have a 30+ year life.

Fast Response

The response rate can be extremely fast to enable load following. The system can ramp from minimum to maximum power output in several seconds.

Depth of Discharge

A thermal battery can also achieve a deeper depth of discharge than the nominal design point when needed, with somewhat lower efficiency, to enable maximum flexibility.

R&D Breakthroughs

High Temperature Pumping

TBC’s technology is based on the ability to pump liquid metal at extreme temperatures using all ceramic or graphite mechanical pumps. This advance was pioneered by TBC’s founder Prof. Asegun Henry, who holds the Guinness World Record.

High Efficiency Thermophotovoltaics (TPV)

TBC’s technology leverages advances in TPV cells designed and fabricated at the National Renewable Energy Lab (NREL) and tested at MIT, that demonstrated a new world record TPV efficiency of 41%.

Emitter Deposition Prevention

TBC’s technology is based on patented strategies, that were first demonstrated at MIT, that prevent deposition of the hot side emitter onto the TPV.


TBC is a MIT spin out commercializing a new low cost ($10-20/kWh-e), grid scale rechargeable battery technology that has been developed at MIT and Georgia Tech over the last 10 years. TBC is currently working on scaling up the technology, with a 1 MWh pilot and commercial demonstrations in the future.



TBC is expanding its team, and is looking for the most talented, creative and experienced engineers. If you’re interested in potentially joining TBC, please send us your resume, and we’ll get in touch if we think you’re a good fit for one of our open positions, or another role.

current Job listings

Senior Mechanical Engineer

Senior Electrical/Controls Engineer

Mechanical Engineer


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