Non-aqueous electrolyte for electrochemical thermocells containing lithium salt and glyme-based solvent

Non-aqueous electrolyte for electrochemical thermocells with enhanced Seebeck coefficients using glyme-based single solvents and LiFSI

This technology utilizes a non-aqueous electrolyte combining lithium salts (LiFSI/LiTFSI) with glyme-based solvents, such as monoglyme or diglyme, in electrochemical thermocells. This approach achieves a higher Seebeck coefficient than aqueous electrolytes and expands the operating temperature range.

Conventional aqueous electrolyte-based thermocells have been limited by low Seebeck coefficients, a narrow operating temperature range of 0–100°C, and relatively high thermal conductivity, which reduces energy conversion efficiency.

This technology uses LiFSI or LiTFSI at a concentration of 0.5–2 M, combined with ethylene glycol dimethyl ether (monoglyme) or diethylene glycol dimethyl ether (diglyme) as a single solvent. This configuration achieves a Seebeck coefficient of 2–3.0 mV/K and an operating range of -50 to 150°C. It can be applied to industrial waste heat recovery, self-powered sensors for polar or space exploration, and wearable body-heat energy harvesters, allowing waste heat to be converted into electricity in environments ranging from sub-zero temperatures to high-heat industrial processes using a single electrolyte.

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Key Features:

• Electrolyte for electrochemical thermocells with a Seebeck coefficient of 2 mV/K to 3.0 mV/K, capable of operating between -50 and 150°C
• Lithium salt composed of LiFSI (Lithium bis(fluorosulfonyl)imide) dissolved at a concentration of 0.5 M to 2 M
• Glyme-based solvent selected from monoglyme (ethylene glycol dimethyl ether) or diglyme (diethylene glycol dimethyl ether)
• Electrochemical thermocell device comprising an electrolyte interposed between a first electrode and a second electrode, both consisting of lithium

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