the EV credit is non-refundable so you need a tax liability equal to it, (before withholding) to get the full benefit. the usual strategy employed to increase tax liability is to take steps to shift 2022 income into 2021 or to defer expenses from 2021 to 2022 (if you itemize).
example
2021 taxes $5,300
ev credit - 5,300 (limited)
2022 taxes 5,300
total taxes two years $5,300
income/expense shifting
2021 taxes $7,500
ev credit - 7,500
2022 taxes 3,500 (income/expense shifting has lowered 2022 taxes. but because of graduated taxes, you save less than the amount you increased 2021 taxes
total taxes two years $3,500
so you see the benefit is that you get to use more of the credit which saves you taxes.
