Place the sweet potatoes, chickpeas, onion, garlic, chili powder, cumin, tomatoes, broth and salt in a 6-quart crockpot.
Stir well, cover, and cook on low for 5 hours until the sweet potatoes yield to a fork but still hold their edges.
Whisk the peanut butter with 1 cup of hot broth from the crock until completely smooth.
Stir the peanut mixture back into the chili and cook uncovered on high for 20 minutes until the sauce looks uniform and glossy.
Add the lime juice and rest for 10 minutes before serving or cooling for the freezer.