The present application provides a zero-buoyancy cable, which comprises a cable; a plurality of floats sheathed on the cable; and a cladding layer configured to tightly wrap the plurality of floats and the cable so as to fix the floats onto the cable. The zero-buoyancy cable provided in the present application can effectively avoid the loss of the float or the sliding of the float on the cable, thereby improving the balance of the zero-buoyancy cable in the water.

The present application provides a zero-buoyancy cable, which comprises a cable; a plurality of floats sheathed on the cable; and a cladding layer configured to tightly wrap the plurality of floats and the cable so as to fix the floats onto the cable. The zero-buoyancy cable provided in the present application can effectively avoid the loss of the float or the sliding of the float on the cable, thereby improving the balance of the zero-buoyancy cable in the water.

An electric current supply system (20) is designed to be at least partially submerged in an electrically conductive liquid during operation thereof, and having at least one electrically conductive component (21, 22, 23, 24) enveloped in liquid-tight material (40). The component (21, 22, 23, 24) has a sacrificial material that is capable of reacting electrochemically with the liquid. Further, the component (21, 22, 23, 24) has at least one gas trap portion (50) at which the sacrificial material occupies a space in the liquid-tight material (40) that is thereby defined with a gas trapping shape. If, in case of damage to the system (20) in an actual submerged state thereof, the component (21, 22, 23, 24) gets exposed to the liquid, it is achieved that an electrochemical reaction occurring at the exposed area of the component (21, 22, 23, 24) and an outflow of electric current to the liquid are stopped.

A positive electrode disclosed herein includes: a positive electrode active material layer containing a first lithium-transition metal composite oxide in a form of secondary particles and a second lithium-transition metal composite oxide in a form of single particles; and a positive electrode current collector. In the first lithium-transition metal composite oxide, a boron compound is placed on the surfaces of the secondary particles, and a porosity of the secondary particles is 2% to 8%. In the second lithium-transition metal composite oxide, an aluminum compound is placed on the surfaces of the single particles. The first and second lithium-transition metal composite oxides each contain nickel at 70 mol % or more relative to the total amount of transition metal elements, and the mass ratio of the first lithium-transition metal composite oxide:the second lithium-transition metal composite oxide is 80:20 to 50:50.

An electric current supply system (20) is designed to be at least partially submerged in an electrically conductive liquid during operation thereof, and comprises at least one electrically conductive component (21, 22, 23, 24) enveloped in liquid-tight material (40). The component (21, 22, 23, 24) comprises sacrificial material that is capable of reacting electrochemically with the liquid. Further, the component (21, 22, 23, 24) comprises at least one gas trap portion (50) at which the sacrificial material occupies a space in the liquid-tight material (40) that is thereby defined with a gas trapping shape. If, in case of damage to the system (20) in an actual submerged state thereof, the component (21, 22, 23, 24) gets exposed to the liquid, it is achieved that an electrochemical reaction occurring at the exposed area of the component (21, 22, 23, 24) and an outflow of electric current to the liquid are stopped.

A self-supporting electric power cable is disclosed. The electric power cable includes an outer jacket portion and a core portion. The core portion includes at least one insulated conductor and at least one supporting cord. The at least one insulated conductor includes a number of individual wires, and the at least one supporting cord includes synthetic fibers. The number of individual wires, individually or arranged in bundles, are arranged in a first lay direction. The at least one insulated conductor and the at least one supporting cord are arranged in a second lay direction. The at least one supporting cord is arranged as a separate unit in a cross sectional sector of the self-supporting electric power cable. Thus flexible and durable power cable for sea use is provided. Also an offshore arrangement is disclosed herein.

A self-supporting electric power cable is disclosed. The electric power cable includes an outer jacket portion and a core portion. The core portion includes at least one insulated conductor and at least one supporting cord. The at least one insulated conductor includes a number of individual wires, and the at least one supporting cord includes synthetic fibres. The number of individual wires, individually or arranged in bundles, are arranged in a first lay direction. The at least one insulated conductor and the at least one supporting cord are arranged in a second lay direction. The at least one supporting cord is arranged as a separate unit in a cross sectional sector of the self-supporting electric power cable. Thus flexible and durable power cable for sea use is provided. Also an offshore arrangement is disclosed herein.

An electric cable includes at least one electric wire, and a plurality of string-shaped bodies each extending in a longitudinal direction of the electric cable and twisting with one another around the at least one electric wire being a core. The plurality of string-shaped bodies has connection parts twisting with one another excluding the at least one electric wire. The connection parts are connected to a frame of an underwater robot.

An electric cable includes at least one electric wire, and a plurality of string-shaped bodies each extending in a longitudinal direction of the electric cable and twisting with one another around the at least one electric wire being a core. The plurality of string-shaped bodies has connection parts twisting with one another excluding the at least one electric wire. The connection parts are connected to a frame of an underwater robot.

An electric cable includes at least one electric wire, and a plurality of string-shaped bodies each extending in a longitudinal direction of the electric cable and twisting with one another around the at least one electric wire being a core. The plurality of string-shaped bodies has connection parts twisting with one another excluding the at least one electric wire. The connection parts are connected to a frame of an underwater robot.