I've seen on designs where there is a TVS transient suppression diode on the voltage supply. For example, when the voltage supply is say a wall plug.
However, are such diodes really necessary in a battery powered system? I can't think of any way where the battery supply could "overshoot" the rated voltage.
Best Answer
It could still happen. Static discharge is one method, inductive switching is another, or perhaps some odd grounding issues bumping up voltages. I would still use TVS diodes on sensitive components.