Write a chemical equation representing the first ionization energy for lithium while using e as a symbol for electron.

It's likely what's wanted is

Li → Li 2 + + 2 e-

The reason is because IEs are usually reported from the neutral atom, that is, IE2 is the energy required to remove two electrons from a neutral Li atom, as above, rather than the additional energy required to remove one more electron from an Li + cation.