SBIR-STTR Award

The proposed program will improve the thermal management of a man-portable thermoelectric generator (TEG) by developing a heat pipe enhanced heat rejection heat exchanger that transfers heat directly to the air when the ambient temperature is low, but uses a small amount of water to promote evaporative cooling when the ambient temperature is high or when increased generating power is required.The use of evaporative cooling can reduce the heat rejection temperature from 110 C for the boiling water case to only 38 C for high heat flux evaporative cooling.In addition, Yankee will develop technology to improve the heat flow to and from the core thermoelectric module by utilizing thin dielectric coatings in place of the traditional ceramic insulating wafers commonly used.This will allow a greater level of power generation for a given available temperature difference.

Yankee Scientific completed a successful Phase I program that developed Thermal Management Technologies (TMTs) for improving how heat flows through a thermoelectric generator (TEG).In the Phase II program described in this proposal Yankee will utilize the improved TMTs to design and build man-portable TEGs products with 35 W and 70 W class outputs that will provide battery charging capabilities to dismounted warfighters.The TEGs will be able to operate on multiple-fuels, with the goal of using locally sourced fuels to recharge batteries.Three main design approaches are proposed for these battery charger TEG products.First, heat pipes will be implemented to transport the high heat flux from the TEG surface to an air cooled heat sink for efficient heat dissipation.Second, a novel TEG geometry will be used to form a cylindrical shaped TEG for capturing heat from a centrally located duct.Third, an ultra-compact TEG battery charger will be designed by taking full advantage of evaporative cooling to boost the TEG power output by 70% over that possible by boiling water.