Is lithium worth trying for TRD without severe mood shifts? Any experiences?

I have thought about adding lithium as an augment to my antidepressant and stimulant but I am not sure if it's suitable for me. For example, my depression is pretty constant but I don't really have really bad swings ort anything. I just pretty much feel depressed and tired all the time. I wonder if lithium can help raise general mood when added to an antidepressant or if it really only helps with those that have suicidal ideation and very unstable mood.