Powertrain electrification has heightened the need for an energy management strategy, which has been a continuing concern in the development of electrified vehicles. The energy management control unit manages power flow between different energy sources in an electrified powertrain that directly affects vehicle performance. Developing an energy management strategy that is compatible with different real-world driving scenarios has opened a significant field of study for researchers. Recent advances and progress in intelligent control approaches have facilitated developing an intelligent energy management strategy. However, there are inadequate numbers of studies on the latest energy management strategies. The presented review paper aims to provide the requirements of intelligent energy management strategies as well as a new categorization of them into principle-based, data-driven, and composite methods. Besides, enabling technologies for implementing an energy management system with a comparison of different controller chips are described to give readers an experimental view. Future trends and existing challenges are presented, which generate fresh insight into energy management strategies.