Grigorieva, 42, is said to be "extremely happy" about taking her music in this new direction, reported TMZ online.
According to her representative Steve Jaffe, the new song 'Dark Secret' will receive a music video, which is scheduled to go into production soon.
Grigorieva's new album will reportedly be released through iTunes sometime in February 2013.
Gibson and Grigorieva made headlines for their fiery romance and acrimonious split.
A year after they went public, the relationship was over with Grigorieva accusing Gibson of violence.
The "Braveheart" star pleaded no contest to misdemeanour battery charges in March, 2011. He had to undergo counselling and was sentenced to community service.
Recordings of the actor using racist and violent language were also leaked.
The former couple share a three-year-old daughter, Lucia, and settled a bitter custody dispute over the girl late last year.