A propulsion system for an aircraft as disclosed herein may include a nacelle, a shaft positioned centrally within a cylindrical passageway of the nacelle, a fan coupled to one end of the shaft, a turbine coupled to an opposite end of the shaft, an electric motor coupled to the shaft, a compressor positioned within the cylindrical passageway, and a solid oxide fuel cell positioned with a hollow ring-shaped interior of the nacelle. The hollow ring-shaped interior may surround and be isolated from the cylindrical passageway. The turbine may be configured to provide primary torque to the shaft while the electric motor may be configured to provide additional torque to the shaft. The electric motor may be powered an electric output of the solid oxide fuel cell while the turbine may be powered at least in part by output gases from the solid oxide fuel cell.

A power source assembly is provided having a fuel cell module configured to provide a first direct current power output; a battery configured to provide a second direct current power output; and an isolated DC/DC converter in electrical connection between the fuel cell module and a load. The isolated DC/DC converter includes a DC/AC portion, an AC/DC portion, and a transformer that connects the DC/AC portion and AC/DC portion. The battery can be electrically connected to the DC/AC portion or the AC/DC portion. The isolated DC/DC converter ensures that the fuel cell module is electrically isolated from the load via the transformer.

A power source assembly is provided having a fuel cell module configured to provide a first direct current power output; a battery configured to provide a second direct current power output; and an isolated DC/DC converter in electrical connection between the fuel cell module and a load. The isolated DC/DC converter includes a DC/AC portion, an AC/DC portion, and a transformer that connects the DC/AC portion and AC/DC portion. The battery can be electrically connected to the DC/AC portion or the AC/DC portion. The isolated DC/DC converter ensures that the fuel cell module is electrically isolated from the load via the transformer.

An electric component for an electric system that includes a working component, a housing that encloses the working component, and an electrical insulator that is disposed between the housing and the working component.

An electric component for an electric system that includes a working component, a housing that encloses the working component, and an electrical insulator that is disposed between the housing and the working component.

A propulsion system for an aircraft as disclosed herein may include a nacelle, a shaft positioned centrally within a cylindrical passageway of the nacelle, a fan coupled to one end of the shaft, a turbine coupled to an opposite end of the shaft, an electric motor coupled to the shaft, a compressor positioned within the cylindrical passageway, and a solid oxide fuel cell positioned with a hollow ring-shaped interior of the nacelle. The hollow ring-shaped interior may surround and be isolated from the cylindrical passageway. The turbine may be configured to provide primary torque to the shaft while the electric motor may be configured to provide additional torque to the shaft. The electric motor may be powered an electric output of the solid oxide fuel cell while the turbine may be powered at least in part by output gases from the solid oxide fuel cell.

A propulsion system for an aircraft as disclosed herein may include a nacelle, a shaft positioned centrally within a cylindrical passageway of the nacelle, a fan coupled to one end of the shaft, a turbine coupled to an opposite end of the shaft, an electric motor coupled to the shaft, a compressor positioned within the cylindrical passageway, and a solid oxide fuel cell positioned with a hollow ring-shaped interior of the nacelle. The hollow ring-shaped interior may surround and be isolated from the cylindrical passageway. The turbine may be configured to provide primary torque to the shaft while the electric motor may be configured to provide additional torque to the shaft. The electric motor may be powered an electric output of the solid oxide fuel cell while the turbine may be powered at least in part by output gases from the solid oxide fuel cell.

A battery system is provided that includes a plurality of battery strings, negative path electrical conductors, positive path electrical conductors, and string balancing resistors. The battery strings are disposed in a parallel configuration. Each battery string includes positive and negative terminals. The negative terminal of each battery string is selectively in electrical communication with a load through a respective negative path electrical conductor, and the positive terminal of each battery string is selectively in electrical communication with the load through a respective positive path electrical conductor. The battery system is configurable in a balancing state wherein the battery system is disconnected from the load and the battery system is configured such that the string balancing resistors cause the battery strings to balance in voltage relative to one another.

A battery system is provided that includes a plurality of battery strings, negative path electrical conductors, positive path electrical conductors, and string balancing resistors. The battery strings are disposed in a parallel configuration. Each battery string includes positive and negative terminals. The negative terminal of each battery string is selectively in electrical communication with a load through a respective negative path electrical conductor, and the positive terminal of each battery string is selectively in electrical communication with the load through a respective positive path electrical conductor. The battery system is configurable in a balancing state wherein the battery system is disconnected from the load and the battery system is configured such that the string balancing resistors cause the battery strings to balance in voltage relative to one another.

Embodiments of a propulsion system are provided herein. In some embodiments, a propulsion system for an aircraft may include an electrical power supply; a motor coupled to the electrical power supply, wherein the electrical power supply provides power to the motor; and a fan disposed proximate a rear portion of an aircraft and rotatably coupled to the motor, wherein the fan is driven by the motor.