They'll be joined by 42-year-old Swede Mattias Ekstroem, a 2 times winner of this Germany Touring Car (DTM) championship and planet rallycross winner, at the Jan 2-14 occasion in Saudi Arabia.
Audi expect are the first producer to take overall victory with an electrified powertrain.
"The Dakar is one of the final experiences on the planet. And it's on the point of a radical shift: the future is electric," said Peterhansel.
"The Dakar is an intense test with this particular technology. We are interested in being the first team to win the Dakar Rally with a electric powertrain."
Sainz is currently competing in electrical racing along with his own team from the Intense E off-road SUV show which began this season.
"At 59, I am still hungry, I would not have obtained with this new challenge," he explained.
The model automobiles will utilize an electric drivetrain provided by a high-voltage battery that can be charged by means of a combustion motor.
The yearly rally began in 1978 because of race from Paris to the Senegalese capital, Dakar, but proceeded from Africa for security reasons in 2009.
Among motorsport's very dangerous and gruelling occasions, the rally is currently held completely in Saudi Arabia following a stint at South America.