Wigan become the 10th club of Bent's career, which includes spells at Blackburn, Ipswich, Leicester, Everton and the Addicks.
However, Bent endured a lean time at The Valley following a £2.5million move from Everton in January last year, scoring just five goals in 52 appearances.
Latics boss Chris Hutchings, though, feels Bent's experience will prove invaluable and said: "It's a great deal. We've got him on loan, which is a convenient arrangement for us.
"Marcus has played the majority of his career in the top flight, he's been there and done it, and knows how to look after himself at this level.
"He is a clever player who can fulfil a number of roles and whose game is far more than just about scoring.
"He's lively and brings others into play. He's a streetwise sort of player, who never gives any less than 100% and is one of those lads you want on your side.
"I've always said that I'll only bring in players who I think will add a new dimension to the squad and I think Marcus fits the bill."