By Katie Marsal

Published: 11:45 AM EST

Last-minute claims would have Apple launching an update to its largest MacBook Pro model as early as Macworld -- and potentially with a crucial change to the computer's battery.

Claiming to have Asian sources, 9 to 5 Mac alleges that a 17-inch MacBook Pro with the sturdier, unibody aluminum design is believed due at the trade event, whose show floor opens Tuesday.

While a major revision of Apple's flagship portable has long been expected, the late rumor asserts that the company won't use the same panel-covered battery layout as with the 13-inch MacBook and 15-inch MacBook Pro. Instead, the 17-inch notebook is said to have a "super slim" battery that can't be removed, not unlike the MacBook Air.

Although a likely concern for professionals who may want the option of swapping batteries, the system design would supposedly make up for its fixed nature through a battery that runs for "much longer" than the five hours of the current model, though it's not known whether silver-zinc batteries or other new energy technology would be used to accomplish this feat.

While the report has yet to be fully corroborated, Mac Rumors also says it has heard whispers of a similar plan. AppleInsider's own sources were the first to suggest the 17-inch MacBook Pro would be delayed but did warn that the gap between the release of this and the 15-inch version could span "several months" as Apple works out design kinks.

Regardless, the electronics maker's keynote at Macworld is increasingly expected to be heavy on computer updates and will likely include a new Mac mini.