She thrilled her hometown crowd at the Atos Markham Pan Am/Parapan Am Centre with a 2-0 victory over fellow Canadian Rachel Honderich in today's women's badminton final.
"It is tough to have to beat a friend," Li said. "To see her lose, it's not something I want. But I guess we're both mature enough to know that when we're on court, it's for yourself."
Li, who won gold four years ago at the 2011 Games in Guadalajara, Mexico, defeated Honderich 21-15, 21-9.
Li and Honderich teamed up together to win doubles bronze earlier in the week.
"It's tough because we both know each other's games so well," Honderich said.
Canada's Toby Ng and Alex Bruce settled for silver in the mixed doubles final. They dropped a 21-9, 21-23, 21-12 decision to Americans Phillip Chew and Jamie Subandhi.
Canadian Andrew d'Souza took silver in the men's singles final after losing to Guatemala's Kevin Cordon 21-13, 21-14.
"He didn't let me really play at the net when I wanted to," d'Souza said. "He didn't let me take the attack. He's very good at keeping his attack and I just had a lot of trouble getting out of it when I played him."
Canada's medal count rose to 97 with Thursday's results. The Canadians lead the medal haul at the Games once again after falling behind the United States.
Canada has earned 38 gold, 36 silver and 23 bronze thus far.
The U.S. had 96 total medals as of Thursday night, including 34 gold.
The Canadians men's and women's team sprint teams took double gold at the first day of track cycling at the Cisco Milton Pan Am/Parapan Am Velodrome.
Hugo Barrette of Cap-aux-Meules, Que., Victoria's Evan Carey and Joseph Veloce of St. Catharines. Ont., edged Venezuela in 44.241 seconds in the men's race while Kate O'Brien and Monique Sullivan topped Cuba in 33.959 seconds in the women's team sprint.
"I couldn't believe the support on every home backstretch you went on," O'Brien said. "You just heard masses of screaming and so to have family and friends and Canadians in general out and being able to support us at home was special."
Gaby Dabrowski and Carol Zhao added another gold medal to Canada's tally, taking first place in women's doubles tennis. They beat Mexico's Victoria Rodriguez and Marcela Zacarias in three sets.
In women's wrestling, Genevieve Morrison won gold in the freestyle 48 kilogram division, beating Peru's Thalia Mallqui.
Canada's streak of gold medals in the Pan American Games pool halted Thursday with a disqualification.
Emily Overholt of West Vancouver, B.C., out-touched Caitlin Leverenz of the U.S. to finish first in the women's 400-metre individual medley, but the youngest member of the Canadian swim team was disqualified for a "non-simultaneous" wall touch during the breaststroke leg of the race.
Swimming Canada appealed the disqualification, but it was upheld by officials.
Leverenz took gold in in 4:35.46, Canadian Sydney Pickrem was second in 4:38.03
Canada's women's basketball team roared to a 101-38 rout of Venezuela in its opening match of the Pan American Games.
Seven Canadians scored in double figures, with Lizanne Murphy leading the way with 15 points. Shona Thorburn had 14, Kim Gaucher and Kia Nurse added 12 each, Nayo Raincock-Ekwune had 11, and Tamara Tatham and Katherine Plouffe chipped in with 10 apiece.
In men's baseball, London, Ont., native Brock Kjeldgaard drove in four runs as Canada secured the tournament's top seed with an 11-4 win over Puerto Rico.
Chris Leroux of Mississauga, Ont., pitched six innings, allowing one earned run on three hits while striking out seven and walking two as Canada remained undefeated through five preliminary games. The Canadians close out round-robin action with a game against the U.S. on Friday. Semifinals begin Saturday with the gold- and bronze-medal games scheduled for Sunday.
In men's golf, Canadian Austin Connelly was tied for fourth after shooting a 2-under 70 in the first round. Teammate Garrett Rank was 27th at 7-over 79.
"They say you can't win on the first day, but you can certainly lose it," Connelly said. "I don't feel like I lost it."
Canada's men's field hockey team is 2-0 after a 1-0 victory over Chile.
Captain Scott Tupper scored on a second-half drag flick for the game's lone goal. The win put Canada in the driver's seat to finish first in Pool B.
The Canadian men's soccer team played to a 0-0 draw with Panama and the men's squash team topped Argentina 2-1 in the semifinal. Earlier, Canada's women's squash team downed Mexico 3-0 in their semi.