Use a vegetable peeler to remove strips of peel from half of the lemon; set peel aside. Squeeze juice from lemon.
Combine apple juice, water, and 1 tablespoon of the lemon juice in a large saucepan. (Save remaining juice for another use.) For the spice bag, place cinnamon, cardamom, cloves, and the lemon peel strips in the center of a 6-inch square of double-thick 100-percent cotton cheesecloth. Bring corners together and tie with a clean string. Add bag to apple juice mixture.
Bring mixture to boiling; reduce heat. Cover and simmer 10 minutes. Remove from heat. Add tea bags; cover and let stand 5 minutes. Remove tea bags and spice bag and discard them. Stir in maple syrup. Serve in mugs. If desired, float apple slices on top of each serving. Makes 8 servings.