Abstract: A high electron mobility transistor device including a channel layer, a first barrier layer, and a P-type gallium nitride layer is provided. The first barrier layer is disposed on the channel layer. The P-type gallium nitride layer is disposed on the first barrier layer. The first thickness of the first barrier layer located directly under the P-type gallium nitride layer is greater than the second thickness of the first barrier layer located on two sides of the P-type gallium nitride layer.

Abstract: The present disclosure relates to hub apparatuses and associated systems. An embodiment of the hub apparatus includes a rotor assembly, a shaft, and a stator assembly. The rotor assembly includes first/second housing components and multiple magnets mounted on one or both of the first and second housing components. The stator assembly includes (1) a coil assembly positioned corresponding to the magnets; (2) a main circuit board fixedly coupled to the coil assembly; and (3) a battery assembly positioned inside the coil assembly and carried by the main circuit board.

Abstract: A portable electrical energy storage device is provided with a frame that includes a plurality of receptacles for receiving a portion of a portable electrical energy storage cell. A cap is provided over the plurality of receptacles and the portion of the portable electrical energy storage cells received in the frame. In some embodiments, a passageway extends between adjacent receptacles. Disposed within the passageway is a plug which exhibits more resistance to thermal energy migration than other portions of the frame that define the adjacent receptacles.

Abstract: The present disclosure relates to hub apparatuses and associated systems. An embodiment of the hub apparatus includes a rotor assembly, a shaft, and a stator assembly. The rotor assembly includes first/second housing components and multiple magnets mounted on one or both of the first and second housing components. The stator assembly includes (1) a coil assembly positioned corresponding to the magnets; (2) a main circuit board fixedly coupled to the coil assembly; and (3) a battery assembly positioned inside the coil assembly and carried by the main circuit board.

Abstract: A portable electrical energy storage device is provided with a frame that includes a plurality of receptacles for receiving a portion of a portable electrical energy storage cell. A cap is provided over the plurality of receptacles and the portion of the portable electrical energy storage cells received in the frame. In some embodiments, a passageway extends between adjacent receptacles. Disposed within the passageway is a plug which exhibits more resistance to thermal energy migration than other portions of the frame that define the adjacent receptacles.

Abstract: A portable electrical energy storage device is provided with a frame that includes a plurality of receptacles for receiving a portion of a portable electrical energy storage cell. A cap is provided over the plurality of receptacles and the portion of the portable electrical energy storage cells received in the frame. In some embodiments, a passageway extends between adjacent receptacles. Disposed within the passageway is a plug which exhibits more resistance to thermal energy migration than other portions of the frame that define the adjacent receptacles.

Abstract: A portable electrical energy storage device is provided with a frame that includes a plurality of receptacles for receiving a portion of a portable electrical energy storage cell. A cap is provided over the plurality of receptacles and the portion of the portable electrical energy storage cells received in the frame. In some embodiments, a passageway extends between adjacent receptacles. Disposed within the passageway is a plug which exhibits more resistance to thermal energy migration than other portions of the frame that define the adjacent receptacles.