Abstract: The present invention relates to a compound capable of lowering the flammability of a non-aqueous electrolyte when included in the non-aqueous electrolyte and improving the life properties of a battery by forming an electrode-electrolyte interface which is stable at high temperatures and low in resistance, and relates to a compound represented by Formula I descried herein, a non-aqueous electrolyte solution and a lithium secondary battery both including the compound, n, m, Ak, and X are described herein.

Abstract: A disc brake enables a parking apparatus to be operated via actuation of an electric motor, thereby permitting easy operation of the parking apparatus. The disc brake comprises a piston to compress a friction pad used for braking of a disc, a caliper housing to receive the piston such that the piston moves linearly therein, and having a cylinder section to which a hydraulic pressure for braking is applied, an actuation shaft rotatably installed within the cylinder section, and having a male screw formed thereon, a compression sleeve installed within the piston to compress or release the piston while linearly moving therein by rotation of the actuation shaft, and having a female screw formed thereon to engage with the male screw of the actuation shaft, an electric motor to rotate the actuation shaft, a multi-stage reduction gear train to transmit rotational force of the electric motor to the actuation shaft.

Abstract: An electric parking brake system capable of achieving efficient operation while reducing generation of noise. The electric parking brake system comprises first and second parking cables to be connected to brakes that are used to stop rotation of wheels of a vehicle, a motor to generate a drive force required to selectively operate the parking cables, a drive gear adapted to rotate in accordance with operation of the motor, a planetary gear unit, and a screw-nut unit. The planetary gear unit includes a sun gear connected to the drive gear in a power transmittable manner, a plurality of planetary gears gearedly connected with the sun gear and adapted to revolve along a periphery of the sun gear, an internal gear formed along a revolving path of the planetary gears and adapted to be gearedly connected with the planetary gears, and an output carrier connected to the planetary gears in a power transmittable manner and adapted to rotate about the same rotating center as that of the sun gear.