Fuel Cell Stacks

Fuel Cell Stacks

Although still under development, NexTech anticipates that SOFC fuel cell stacks and fuel cells will be sold into various markets including military, stationary combined heat and power (CHP), automotive power for hybrid vehicles, and large-scale stationary for utility-scale power production. The key drivers for the markets include price and technology specific benefits, such as quiet operation and improved efficiency.

NexTech is developing a number of manufacturing technologies and designs for SOFCs including:

Electrolyte Supported Planar Stacks
NexTech Materials is developing solid oxide fuel cell and stack technology based on a new planar cell design, called the FlexCell^TM This cell design offers a number of important advantages relative to contemporary cell and stack designs, primary among them being the ability to design SOFC power systems with high gravimetric and volumetric power density, high electrical efficiency, and the ability to use sulfur-containing fuels.
Enabling attributes include:

Mechanical integrity and flexibility

Thin electrolyte for high performance

Small repeat units for high power density

Dense perimeter for ease of sealing

Thin anodes for high fuel utilization

Thin anodes for redox cycling tolerance

Anode flexibility - sulfur tolerance

For more information about our FlexCell^TM, please click here.

Tubular Fuel Cells
Fuel cell stacks based on Anode Supported Electrolyte Tubes consist of bundles of interconnected tubes which are typically sealed into common fuel delivery and exhaust manifolds. This bundling approach simplifies sealing and interconnnection, as these interfaces can be maintained either at or below the operating temperature of the stack. By virtue of the thin electrolyte layer, performance of anode-supported electrolyte tubes can be high even at low temperatures. The relatively thick electrode support and the tubular geometry make anode supported tubes mechanically robust and a candidate for portable power sources and auxiliary power units, where ruggedness is of primary concern.

Fuel cell stacks based on Cathode Supported Electrolyte Tubes consist of bundles of interconnected tubes which are typically sealed into a common air plenum, with oxidant being delivered down the axis of the tube to a closed end. Depleted air is collected at the open end of the tube. NexTech's cathode supported electrolyte tubes are produced using in-house extrusion and co-firing technology. Cathode supported tubes have been evaluated for many years in centralized power systems where hybridization with turbines allow very high efficiencies to be achieved, as well as in decentralized stationary power systems where combined heat and power are provided to a residence. In addition to conventional SOFC operation, cathode supported electrolyte tubes are of interest in the development of direct carbon fuel cells for a range of system concepts.

For more information about our tubular fuel cells, please click here