Lawyers of former Chadian dictator
Lawyer Ibrahim Diawara said Senegal's President Macky Sall should intervene and request the release of Habre, who was sentenced to life in prison by a Senegalese court at the end of May.
The trial against 73-year-old Habre had been unfair due to a technicality, Diawara said.
The jury empanelled to try the case had not been appointed in accordance with the law, the attorney said.
The chamber was created in 2013 amid criticism that the International Criminal Court in The Hague has in the past unfairly targeted African leaders.
The case against Habre was the first-ever trial of a former head of state in sub-Saharan Africa.
Habre was found guilty of having coordinated crimes against humanity, which included illegal detention, repression and sexual slavery.
He was also convicted for war crimes, torture and sexual slavery.
The judges concluded that Habre had systematically hunted down opponents, personally committed rape and torture and given written orders for execution.
Rights groups estimate that Habre is responsible for the deaths of around 40,000 people during his rule.
About 200,000 people were reportedly tortured by his regime.
After living freely in exile in Senegal for 22 years, Habre was detained in Dakar in July 2013.
The US President Barack Obama had during a visit to Senegal expressed his support for Habre to be tried.
Habre's arrest had been delayed for years by Senegal's administration, ignoring Belgian courts' efforts to speed up the process and try him in Europe.