Tenth-seeded Li of China rallied from a 1-5 deficit in the third set of her semifinal to post a 3-6, 6-3, 7-5 comeback victory over 16th-seeded Czech Lucie Safarova.
Li used five aces and made good on 4-of-6 break points in the victory.
Meanwhile, fifth-seeded Kvitova of the Czech Republic overcame a lengthy rain delay to best seventh-seeded Caroline Wozniacki of Denmark 3-6, 6-2, 6-3 in Sunday's other semifinal.
Kvitova recorded five aces in the triumph.
The pair will meet Monday evening in the finale.