Lakshmi is the mother goddess, and the consort of Vishnu. She is the patron of wealth (both material and spiritual), prosperity, good fortune and is the embodiment of beauty and grace. In this form, she is bestowing gold coins of prosperity and the elephants flanking her represent her royal power.
Kali is one of the many forms of Shakti. Maha Kaali is the fiercest of all goddesses of Hinduism. The word Kali has its roots in the Sanskrit word "Kaal", which means time. And nothing escapes from time. Goddess Kali is sometimes referred as the goddess of death. But actually Kali brings the death of the ego. Even in the scriptures, she has killed demons but not anyone else. Kali is also not associated with Yama (the Hindu God of Death). Kali is considered a form of mother too.