What happens to the chemical energy of a lithium-ion battery as it is discharge to power a laptop computer? does it increase, decrease, or remain unchanged?

The answer to this question would be decreased.

When a battery discharged, it will produce electrical energy that will power up your laptop. Law of conservation of energy state that the total energy should be constant since you cant make energy but can transform it.

In this case, the chemical energy would be decreased as it was transformed into electrical energy.