How does the Cold Bond™ Manufacturing Process enhance Wire Mesh?
Cold Bond™ is a unique metallic bonding process developed to stabilize wire mesh for batteries, fuel cells, green hydrogen production and other processes.
Woven wire meshes are becoming key components in current and emerging electrical energy generation and storage technologies – serving as anodes and cathodes, catalytic surfaces, permeable membranes, or chemical deposition substrates. In order for these technologies to advance from prototype to production, engineers must consider not just the science, but also the manufacturability, ensuring the mesh is fit for function. A mesh that works in one of these devices must maintain its both its shape and electrical continuity far beyond the proof-of-concept phase, while keeping costs competitive. Depending on the application, the mesh must withstand any number of chemical, vibrational, electrical, and fabrication stresses. The two traditional choices for fortifying a mesh to meet these requirements are calendaring and sintering.
- Calendaring is a process where a length of mesh is fed between two high pressure rolling pins that flatten the mesh, decreasing its overall thickness, flattening the outer faces of the knuckles, and nesting the mating faces of the knuckles into one another. This nesting mechanically interlocks the warp and shute wires in the mesh, stabilizing the overall pore structure and reducing fraying at the edges. Even though calendaring will increase contact between intersecting wires, the lack of metallic bonding means electrical continuity can deteriorate as the contact surfaces develop corrosion or accumulate impurities.
- Sintering is a process where a piece of mesh is heated in a furnace to just below melting temperature. Even though the metal does not melt, at near-melt temperature metal surfaces in contact will metallically bond with one another. Mesh is usually calendared prior to sintering in order to increase the surface area in contact, making for even more robust metallic bonding. The advantages of sintering over calendaring alone are even greater stabilization, fray resistance, and rigidity. The disadvantages of sintering are that it requires more labor and energy, and therefore is a much more expensive process. It can also require additional heat treating to restore hardness lost during the annealing temperatures reached during sintering.
There is a third, lesser-known method available to stabilize wire mesh, providing superior contact between surfaces over calendaring, without incurring the cost or production headaches of sintering. This process is known as Cold Bond™
Cold Bond™ was developed about 20 years ago and has been used extensively by one manufacturer providing wire mesh to the battery, fuel cell and most recently electrolyzer manufacturing industry. Cold Bond™ is the process of stabilizing a mesh which imparts some of the desirable characteristics of sintering along with the simplicity and cost effectiveness of calendaring. As with calendaring, the weave is mechanically locked together, stabilizing the pore structure and the edges. In addition, Cold Bond™ also achieves some metallic bonding between interfacing surfaces, enough that all parts of the mesh maintain full electrical continuity.
Characteristics that make Cold Bond™ wire mesh ideal for electrical applications:
- As a room temperature process, Cold Bond™ does not reanneal the mesh.
- Metallic bonding means that all parts of the mesh maintain electric equipotential.
- Consistent thickness of mesh is achieved – key to meeting specified tolerances required in a cell stack.
- Optimal results on square weave mesh with at least 50% open area.
- Metallically bonds both ferrous and non-ferrous alloys.
- Cold Bond™ is a continuous process applicable to mesh of unlimited length, up to 24” wide – much easier to process than the batch production of sintering.
|Comparison Chart||Cold Bond™||Sinter||Calender|
|Flattens mesh to lock weave||Slightly||Yes||Yes|
|Metallically bonds weave||Yes||Yes||No|
|Reliable electric equipotential||Yes||Yes||No|
|Mesh size limitations||24″W x ∞L||Furnace capacity||60″W x ∞L|
If you work with fuel cells, batteries, electrolyzers, or other clean energy sources, speak with a wire mesh expert about the advantages of Cold Bonded™ wire mesh for your membranous conductors, cell stacks and electrolyte substrate applications.
Gerard Daniel Expertise
At Gerard Daniel, we’ve been sourcing, weaving, and distributing wire mesh for 70 years and stock the largest range of inventory in North America. Our application engineers use their deep expertise in woven mesh and components to develop the most effective solution, collaborating with your design, development, and production teams to ensure the lowest cost to manufacture.