anode and cathode in lithium ion battery? By definition, the anode is the electrode where oxidation takes place, the cathode is the electrode where reduction takes place.

When I am charging the Li-ion battery, positive electrode undergoes oxidation and hence I may call it the anode. When I am discharging the Li-ion battery, negative electrode undergoes oxidation and I may call it the anode. Is this correct?

Do the anode and cathode interchange for charging and discharging?
This is indeed correct, since, as you said, the cathode is per definition the site for reduction and the anode for oxidation, both names have to be "switched" when viewing electrolysis (charging of the Li-ion battery) and galvanic cells (discharging of the Li-ion battery). What does not change is the location of the + and - pole.

A good way to remember the site of oxidation and reduction is the word pair an-ox /cat-red.