Lithium is the light metal that stores energy, read as charge, power and keeping going. Dream books link it to recharging and to balancing energy levels.
When this appeared in your dream, what were you feeling?
My Cosmic Code has a private dream journal. Write a dream down and the app picks out the symbols in it, shows what dream books say about them and, over time, which words recur across your entries. The journal is stored on your device only.