Abstract: Disclosed is an electrode assembly, a battery, and a battery pack and a vehicle including the same. In the electrode assembly, a first electrode, a second electrode, and a separator interposed therebetween are wound based on a winding axis to define a core and an outer circumference. The first electrode includes a first active material portion coated with an active material layer and a first uncoated portion not coated with an active material layer along a winding direction. At least a part of the first uncoated portion is defined as an electrode tab by itself. The first uncoated portion includes a first portion adjacent to the core of the electrode assembly, a second portion adjacent to the outer circumference of the electrode assembly, and a third portion interposed between the first portion and the second portion. The first portion or the second portion has a smaller height than the third portion in the winding axis direction.

Abstract: An electrode assembly, a battery, a battery pack and a vehicle including the same are provided. In the electrode assembly, the uncoated portion of an electrode includes a segment region divided into a plurality of segments, and the segment region includes a plurality of segment groups separated by a group separation pitch along a winding direction. One end of the electrode assembly includes a plurality of segment alignments. In winding turns corresponding to the plurality of segment alignments, group separation pitches of segment groups disposed in a same winding turn are substantially identical, and separation pitches of the segment groups is greater in a winding turn of a region adjacent to the outer circumference of the electrode assembly than in a winding turn of a region adjacent to the core of the electrode assembly.

Abstract: A fixed angle hybrid centrifuge rotor includes an outer portion of composite material reinforced with fiber at least along a peripheral direction, an inner portion having stiffness less than ? of stiffness of the outer portion and provided with a plurality of slots receiving specimens, and a reinforcer of composite material mounted into the slots of the inner portion, the reinforcer fabricated from material having higher stiffness than that of the inner portion and reinforced with fiber along at least peripheral direction of the slot. The reinforcer penetrates the inner portion and at least a part of the reinforcer downwardly protrudes from the inner portion. The rotor can rotate at a high speed and provides improved safety.

Abstract: A resonance generating apparatus for testing blade fatigue with reduced side load includes a mounting portion comprising a saddle including a groove corresponding to an external surface of a blade, and an assembling portion positioned on an external side of the saddle and joined by tightening members so that the saddle presses against the blade, a resonance generator including an actuator to generate a linear movement, a coupler(s) to maintain phase of a blade motion the same as an actuator rod, and a linear guide to guide a direction of linear reciprocating motion of an actuator body, and weights mounted on opposite faces of the actuator body to move in association therewith, and varied in a lengthwise direction of the blade so a center of gravity of moving masses of the actuator body in linear reciprocation and the additional weights is positioned on an axis of the actuator rod.

Abstract: The present invention relates to a resonance generating apparatus with maximized moving mass ratio for a blade's fatigue testing, which includes a light-weighted mounting portion provided in contact with an external surface of the blade, a plurality of actuators provided on an external side of the mounting portion, and a resonance generator configured to generate bending loads in association with displacement of rods of the actuators, and to reciprocate in parallel relationship with a moving direction of the actuator rod and simultaneously to prevent the resonance generator's motions in all directions except for a direction of testing, and a fatigue testing method using the same.

Abstract: A fixed angle hybrid centrifuge rotor includes an outer portion of composite material reinforced with fiber at least along a peripheral direction, an inner portion having stiffness less than ? of stiffness of the outer portion and provided with a plurality of slots receiving specimens, and a reinforcer of composite material mounted into the slots of the inner portion, the reinforcer fabricated from material having higher stiffness than that of the inner portion and reinforced with fiber along at least peripheral direction of the slot. The reinforcer penetrates the inner portion and at least a part of the reinforcer downwardly protrudes from the inner portion. The rotor can rotate at a high speed and provides improved safety.