The IRS says, "If you cannot use part of the personal portion of the credit because of the tax liability limit, the unused credit is lost." That is, Line 21 on the 8936 says, "Enter the total, if any, credits from Schedule 3 (Form 1040), lines 48 through 51"; this amount is subtracted from the tax on line 11 (1040).
So the Electric Drive Motor Vehicle Credit that you take in this year is the lesser of the calculated credit or the tax due after the credits on line 48-51 are subtracted.
Any unused Electric Drive Motor Vehicle Credit is lost.
Please see form 8936 and its instructions at https://www.irs.gov/forms-pubs/about-form-8936