Black Vulcan was a member of the Super Friends on the Hanna-Barbera cartoon series The Super Friends. This superhero team was essentially the cartoon version of DC Comics' premier super-team the Justice League of America. Black Vulcan was originally supposed to be the DC Comics character Black Lightning, but he was changed slightly and made into a new character for legal reasons. Despite the change in name and costume, Black Vulcan is clearly based on Black Lightning and can be thought of as this cartoon series' analog to Black Lightning.
Black Lightning was portrayed as a devout Protestant Christian. His creator, Tony Isabella, identified Black Lightning as a member of the American Baptist Convention (also known as "Northern Baptists"). This is a major Protestant denomination that split from the Southern Baptist Convention over the issue of slavery. The Southern Baptists believed slavery was acceptable and a Biblically-granted right while the Northern Baptists believed that slavery was antithetical to the teachings of Christianity. Most black Baptists who were members of the denomination at the time of the schism ended up becoming members of the American Baptist Convention (the "Northern Baptists") rather than the pro-slavery Southern Baptists. None of this really has anything to do with the Black Vulcan's history, which takes place many decades after the Baptist denominational schism which formed the Southern Baptist and American Baptist Conventions.
The religious affiliation of Black Vulcan was never overtly identified in the Super Friends animated series. Indeed, it was extremely rare at that time for cartoons intended for children to make explicit reference to precide religious affiliation. Black Vulcan is classified as a Northern Baptist purely because he is a slightly changed version of Black Lightning, who is a Northern Baptist.