Robust Seal for High Temperature Electrochemical Devices
APPLICATIONS OF TECHNOLOGY:
- Solid oxide fuel cells
- Oxygen generators
- Gas filtration
- Processes using ceramic membranes
- Greatly expands the choice of sealing materials
- Promises inexpensive manufacturing, high sealing quality, and long lifetime
- Applicable to devices of any geometry, including planar and tubular
- Allows alternative electrical and mechanical connection strategies between neighboring devices, manifolds, etc.
Sealing of high temperature electrochemical devices is a major technical barrier to their commercialization. No dominant sealing technology exists; all have drawbacks that have precluded their widespread acceptance.
Berkeley Lab researchers Craig Jacobson and Michael Tucker have invented a seal that overcomes many of the disadvantages of existing seals and sealing methods. The new seal allows manufacturers to choose from a broader array of sealing materials and has other features that may significantly reduce manufacturing costs, improve seal quality, and lead to longer lifetimes. The new seal can be used with almost any conceivable device design and should allow for alternative electrical and mechanical connection strategies between neighboring devices, manifolds, and electrical conduits.
- Available for licensing.
Easy Joining of Dissimilar Materials in Concentric Tubes
APPLICATIONS OF TECHNOLOGY:
- Electrochemical devices, e.g. solid oxide fuel cells
- Filter elements
- Gas sparger/bubbler/fluid manifold
- Wear coatings
- Thermal barrier layers
- Chemical resistance coatings
- Current collection
- More robust than current methods
- Promises easier manufacturing
- Allows inspection of the outside of an internal layer
Steven Visco, Mike Tucker and colleagues have invented an efficient method for joining concentric tubes of dissimilar materials to form a robust, composite tubular structure. The method was developed in the context of tubular solid oxide fuel cells but could be applied to filter elements, gas manifolds, or any other device with concentric tubes where the pore size, total porosity, chemical, mechanical, or electronic properties must vary in the radial direction.
Unlike current processes, the Berkeley Lab method makes it unnecessary for the tubes to display adhesive, chemical, or sintering bonding to each other. The inventors exploit radial shrinkage during sintering to join tubular layers to one another primarily by compressive and friction forces, and possibly some mechanical interlocking, thus “shrink-wrapping” an outer tube onto an inner tube. The new method is not only simple, but promises to produce more robust joining. It also enables inspection of the outside of an internal concentric layer before an external layer is applied. This is not possible in a manufacturing scheme where all of the layers are produced as a single green body and subsequently co-sintered.
- Published PCT Patent Application WO2008/016345 available at www.wipo.int. Available for licensing or collaborative research.