A battle carrier has two hangar bays to launch wings of fighters and/or frigates from. In the early 25th century, the difference between carriers and battle carriers were the superior maneuverability but weaker shielding of the latter. In 2409, the Kar'Fi-class battle carrier was in service of the Fek'Ihri Horde and the Klingon Empire. (STO mission: "Afterlife", Fek'Ihri ship description on the Official Homepage)
Heavy Escort CarrierEdit
Heavy escort carriers were heavy escorts modified to house a single hangar bay. This carrier variant was introduced by Starfleet with the Armitage-class heavy escort carrier in 2409. Older Starfleet heavy escort classes, such as the Akira-class, were also capable of serving as heavy escort carriers. (Season 6 Dev Blog #5: Heavy Escort Carrier).