Thermal Conversion and Storage in One Solid-State Device

Waste heat makes up a very large fraction of the energy produced today. The process chain of energy conversion of chemical energy into power is subject to up to 72% loss. Recovering this waste heat will be crucial for enhancing the efficiency of processes.

Today approaches such as thermoelectric energy conversion are receiving interest due to their ability to turn waste energy back into useful electrical energy.

However, the wider adoption of this technology is being held back due to the low efficiency (< 5-8%) of current thermoelectric devices, the need for a temperature gradient, and the scarcity of state-of-the-art materials. Recently, a new device, the 'thermal battery', was proposed. Until now, the thermal battery concept has been explored using liquid electrolytes.

However, liquid electrolytes severely restrict the operation temperature range to T<50 K.

In PowerPact, the goal is to create a pioneering prototype that features a high-temperature battery made of solid-state electrolytes and electrodes using ""artificial oxide heterostructures,"" which can stack together on demand.

This design will enable the battery to charge at high temperatures and discharge at low temperatures, effectively using waste heat recovery.

The overall goal is to achieve a proof of concept capable of storing energy within the range of milliampere-hours (mAh) to watt-hours (Wh) that is suitable for small consumer electronics.

Through this development, we seek to lay the basis for a new class of 'thermal battery' that directly captures and stores waste heat.

To realize this vision, we need to radically redesign the 'thermal battery' technology, where our thermal battery features a unique charging mechanism; it operates at a constant temperature.

This breakthrough advances a new concept in thermal batteries, designed to connect current thermoelectric technologies with solid-based thermal batteries. To date, however, solid-state thermal batteries have remained elusive.