Czech Kvitova, who won the Japan Open last weekend, overcame Italian fifth seed Sara Errani 6-4 6-7(3) 6-3 in their third round clash at the prestigious $5 million Beijing tournament.
"I felt like I played very well at the beginning of each set, but then there were some turning points and she would start playing better, and I would make some easy mistakes," Kvitova told the WTA website.
"It was really up and down today - a big fight - but I expected that. I just kept fighting and I'm happy to win today."
Li, the first Asian to win a Grand Slam singles title when she triumphed at the 2011 French Open, had the crowd happy as she scored a break in her 13th seeded opponent's first service game.
The world number five ran in to trouble though as she attempted to serve out the set as Lizicki broke back to level at 5-5 only for Li to break again and win it 7-5.
Another break came midway through the second set as Li wrapped it up 6-4 despite a match total of seven double faults. That serving issue will need to be resolved if she is to find a way past in-form Kvitova.
"It's always tough to play against her - she has a huge, big serve, and also forehand," Li said.
"She broke my rhythm a little bit today. I need three or four shots to get my rhythm, and sometimes she just comes and shoots the ball in one shot. So I was a little bit shocked, but I'm really happy to win.
"I don't think either of us played to the best of our ability, but we worked really hard on the court, and I'm very glad to see that no matter how close the score was, I stayed calm and controlled myself."
World number one Serena Williams is back in action on Thursday when she takes on Maria Kirilenko in the third round.
There were also several second-round matches on Wednesday as world number four Agnieszka Radwanska eased through to the last 16 courtesy of a 6-3 6-2 win over Madison Keys, while Ana Ivanovic was shocked by Polona Hercog.
Radwanska beat Keys at this year’s Wimbledon and saw off her challenge in one hour and 15 minutes.
In a ruthless first set, Radwanska converted her only break point to take the set 6-3 before three breaks of serve were enough to secure a straight sets win over her talented American counterpart.
"I played her at Wimbledon a few months ago, so I kind of knew what to expect, especially the big serve," Radwanska told the WTA website. "We played a really long three set match there. She was really serving unbelievable.
"So I knew I had to stand two steps backwards to reach that serve. But I don't think her percentage of first serves was as good as the matches before - it was a little bit easier for me today.
"But she's one of the youngest talented players coming out. Last year I was asked me to name which of the players can be the most dangerous to the top seeds, and I actually said it's Madison Keys, because she can play very good tennis.
"In a couple of years we're going to see her more often."
Former world number one Ivanovic, meanwhile, lost 6-4 6-4 to Slovenian qualifier Hercog, who broke once in each set and never faced a break point in a tight encounter.
"It was a big challenge for me to go out there on a big court and play against Ana Ivanovic, and I'm just really happy the way it turned out," Hercog said.
"It's probably one of the biggest victories for me. I beat (Marion) Bartoli before when she was Top 10, but Ana is on her way back so it's a very big win for me."
Other second-round matches on Wednesday saw eighth seed Jelena Jankovic beat Kazakh qualifier Galina Voskoboeva 6-3 5-7 6-3 in two-and-a-half hours, while Andrea Petkovic followed her first-round upset over Victoria Azarenka with a 4-6 6-4 6-1 win over twice China Open winner Svetlana Kuznetsova.