Place chicken wings on 2 jelly-roll pans coated with cooking spray.
Bake wings for 1 hour or until browned.
Place wings in a stockpot.
Pour 1/2 quart water into each jelly-roll pan, scraping to loosen browned bits.
Pour water mixture into stockpot.
Add remaining 4 quarts water, celery, and remaining ingredients to stockpot. Bring to a boil. Reduce heat to low, and simmer 4 hours, skimming off and discarding foam as needed. Strain stock through a fine sieve into a large bowl; discard solids. Cool stock to room temperature. Cover and refrigerate 8 hours. Skim solidified fat from surface of stock; discard fat.