Method and apparatus for adding electrolyte to a fuel cell stack

Patent · Tue Jun 24 04:00:00 EDT 1986

OSTI ID:5404813

Congdon, J V; English, J G

A process is described for adding electrolyte to a fuel cell stack, the stack comprising sheet-like elements defining a plurality of fuel cell units disposed one atop the other in abutting relationship, the units defining a substantially flat, vertically extending face, each unit including a cell comprising a pair of sheet-like spaced apart gas porous electrodes with a porous matrix layer sandwiched therebetween for retaining electrolyte during cell operation, each unit also including a sheet-like substantially non-porous separator, the separator being sandwiched between the cells of adjacent units. The improvement described here consists of: extending at least one of the sheet-like elements of each of a plurality of the fuel cell units outwardly from the stack face to define horizontal tabs disposed one above the other; depositing dilute electrolyte directly from electrolyte supply means upon substantially the full length, parallel to the stack face, of at least the uppermost tab, the tabs being constructed and arranged such that at least a portion of the deposited electrolyte cascades from tab to tab and down the face of the stack, the deposited electrolyte being absorbed by capillary action into the elements of the stack, the step of depositing continuing until all of the electrodes and matrix layers of the stack are fully saturated with the dilute electrolyte; and thereafter evaporating liquid from the saturated elements under controlled conditions of humidity and temperature until the stack has a desired electrolyte volume and electrolyte concentration therein.

• Assignee: United Technologies Corp., Hartford, CT
• Patent Number(s): US 4596749
• OSTI ID: 5404813
• Country of Publication: United States
• Language: English

Related Subjects

30 DIRECT ENERGY CONVERSION
300503* -- Fuel Cells-- Materials
Components
& Auxiliaries
CONTROL
DIRECT ENERGY CONVERTERS
ELECTROCHEMICAL CELLS
ELECTRODES
ELECTROLYTES
EVAPORATION
FLUIDS
FUEL CELLS
HUMIDITY CONTROL
LAYERS
LIQUIDS
MATERIALS
PHASE TRANSFORMATIONS
POROUS MATERIALS
TEMPERATURE CONTROL