Lee thrashed 101 from only 60 balls and Sune Luus made an unbeaten 61 as South Africa posted a huge total of 195-3 from their 20 overs.

Pace bowler Shabnim Ismail (3-8) took two wickets in two balls before a superb one-handed grab from Laura Wolvaardt had Thailand teetering at 15-4.

Luus also impressed with the ball, taking 3-15 with her leg-spin as Thailand were bundled out for 82 with five balls remaining.

The Proteas are now top of Group B, having won both of their matches and with a superior net run-rate to second-placed England.

South Africa produced a stunning display at Manuka Oval to post the highest total in the competition's history, hitting a combined total of 22 fours and seven sixes.

Lee alone hit 16 fours as she registered her first T20 international century, and the second hundred of the tournament.

South Africa are next in action against West Indies on Tuesday, when Thailand play Pakistan earlier on the same day, also at the Sydney Showground.

Proteas shine as both sides drop catches

This was not a classic encounter by any means, with both sides dropping easy catches and stumbling in the field.

A century for Lee felt almost inevitable as she clubbed two boundaries from the first over, and she pierced the field with ease as Thailand's heads dropped.

Captain Dane van Niekerk was furious to fall in the second over, hitting a full toss straight to mid-wicket, but Lee bludgeoned the attack with ease, despite being dropped twice.

Her century celebration was muted - a gentle raise of the arms to the South Africa dugout - before she chipped her next delivery back to bowler Sulepoorn Laomi.

Luus took the initiative after Lee fell, hitting five fours and two sixes in her 41-ball innings, and she was supported by Chloe Tryon's rapid 24 from 11 balls.

There was some farcical fielding from South Africa, with two terrible dropped catches in the first two overs, but Ismail's pace accounted for the Thailand top order.

Nattakan Chantam was superbly run out off the first ball of Ismail's second over before the right-armer, probably the quickest bowler in the women's game, bowled Nannapat Koncharoenkai and Naruemol Chaiwai with consecutive balls.

It was a superb spell, with Ismail touching the 76mph mark, before Wolvaardt's stunning catch, diving to her right at cover, added to Thailand's woes.

All-rounder Onnicha Kamchomphu provided some entertainment for Thailand, including hitting their first six of the tournament, but there was just not enough firepower in their line-up.

'The dropped catches are a worry' - what they said

South Africa opener Lizelle Lee: "It was one of those days when it came off for me. We struggled a bit in the powerplay but then I had a really good partnership with Sune Luus.

"It hasn't come off for me in the last few games but I'm happy it did today and it gives me confidence for the rest of the tournament."

Thailand captain Sornnarin Tippoch: "All credit to Lizelle, she hit the ball really hard, but we didn't get the lines and lengths right so there are things to improve on with our bowling and our fielding as well.

"It was a big score on the board but we tried to go out there and play with courage."

South Africa captain Dane van Niekerk: "Our fielding let us down, we want to be at our best whoever we play.

"The dropped catches are a worry. My team-mates are disappointed in that but there isn't much time before the next game so we can't dwell on it."