An energy storage device includes: an electrode assembly; a positive electrode current collector and a negative electrode current collector connected to the electrode assembly; and a container configured to house the electrode assembly and the positive electrode current collector and the negative electrode current collector, wherein the container has recessed portions, a connecting portion of the positive electrode current collector and a connecting portion of the negative electrode current collector respectively connected to the electrode assembly are housed in the recessed portions, respectively, the electrode assembly has a tab portion which includes a connecting portion connected to the positive electrode current collector and a tab portion which includes a connecting portion connected to the negative electrode current collector, and the tab portions have a bent portion respectively.

A lithium-ion cell includes a ribbon-shaped electrode-separator assembly having an anode, a separator, and a cathode in a sequence anode/separator/cathode. The anode has a ribbon-shaped anode current collector having a first longitudinal edge, a second longitudinal edge, and two ends, wherein the anode current collector has a strip-shaped main region loaded with a layer of negative electrode material and a free edge strip extending along the first longitudinal edge that is not loaded with the electrode material. The cathode has a ribbon-shaped cathode current collector, wherein the cathode current collector has a strip-shaped main region loaded with a layer of positive electrode material and a free edge strip extending along the first longitudinal edge that is not loaded with the electrode material. The negative electrode material containing the at least one active material in a range of from 20 wt % to 90 wt %.

An electrochemical apparatus includes a housing, an electrode assembly disposed inside the housing, a first tab group, and a first adapting piece electrically connected to the first tab group and extending out from the housing. The electrode assembly is configured to be a winding structure including a first electrode plate. The first tab group includes M first tabs connected to the first electrode plate. A thickness direction of the electrode assembly is defined as a first direction. In the first direction, the electrode assembly includes N layers of the first electrode plate, N being greater than M. The M first tabs are each connected to the first electrode plate. A plane passing through a winding center axis of the electrode assembly and perpendicular to the first direction is defined as a winding center plane. The M first tabs are disposed on two sides of the winding center plane.

An electrochemical apparatus includes a housing, an electrode assembly disposed inside the housing, a first tab group, and a first adapting piece electrically connected to the first tab group and extending out from the housing. The electrode assembly is configured to be a winding structure including a first electrode plate. The first tab group includes M first tabs connected to the first electrode plate. A thickness direction of the electrode assembly is defined as a first direction. In the first direction, the electrode assembly includes N layers of the first electrode plate, N being greater than M. The M first tabs are each connected to the first electrode plate. A plane passing through a winding center axis of the electrode assembly and perpendicular to the first direction is defined as a winding center plane. The M first tabs are disposed on two sides of the winding center plane.

At one edge of a positive electrode plate in a winding axis direction of an electrode body, two positive electrode tabs per turn are provided to protrude from the edge. At the other edge of a negative electrode plate in the winding axis direction of the electrode body, two negative electrode tabs per turn are provided to protrude from the edge. The multiple positive electrode tabs provided to protrude from the positive electrode plate include multiple types of positive electrode tabs having different protrusion lengths and proximal end widths, and the multiple negative electrode tabs provided to protrude from the negative electrode plate include multiple types of negative electrode tabs having different protrusion lengths and base end widths.

At one edge of a positive electrode plate in a winding axis direction of an electrode body, two positive electrode tabs per turn are provided to protrude from the edge. At the other edge of a negative electrode plate in the winding axis direction of the electrode body, two negative electrode tabs per turn are provided to protrude from the edge. The multiple positive electrode tabs provided to protrude from the positive electrode plate include multiple types of positive electrode tabs having different protrusion lengths and proximal end widths, and the multiple negative electrode tabs provided to protrude from the negative electrode plate include multiple types of negative electrode tabs having different protrusion lengths and base end widths.

An electrode assembly comprises: a first electrode plate, a second electrode plate and a first layer containing an insulating material, the first layer is sandwiched between the first electrode plate and the second electrode plate, and the first electrode plate, the second electrode plate and the first layer are stacked and then partially folded back to form the electrode assembly; the first electrode plate includes a first surface and a second surface that are opposite to and connected with each other, the first surface and the second surface are formed by the folding-back and separated by an inflection point of the folding-back; a first distance is provided between the first surface and the second surface in a first direction; the first distance is different along a second direction perpendicular to the first direction.

An electrode assembly comprises: a first electrode plate, a second electrode plate and a first layer containing an insulating material, the first layer is sandwiched between the first electrode plate and the second electrode plate, and the first electrode plate, the second electrode plate and the first layer are stacked and then partially folded back to form the electrode assembly; the first electrode plate includes a first surface and a second surface that are opposite to and connected with each other, the first surface and the second surface are formed by the folding-back and separated by an inflection point of the folding-back; a first distance is provided between the first surface and the second surface in a first direction; the first distance is different along a second direction perpendicular to the first direction.

An electronic device includes an electrode assembly. The electrode assembly is configured to be a wound structure and is provided with a first bending section. The electrode assembly comprises a first electrode plate, a second electrode plate, and a conductive member. The first electrode plate includes a first current collector and a first active material layer, and along a winding direction, the first current collector includes a first part and a second part that are connected in sequence. Both surfaces of the first part are arranged with the first active material layer, an inner surface of the second part is provided with the first active material layer, and the second part includes a bending part located at an outermost layer of the first bending section. The conductive member connects the outer surfaces of the first part and the second part, and/or covers on the outer surface of the bending part.

An electronic device includes an electrode assembly. The electrode assembly is configured to be a wound structure and is provided with a first bending section. The electrode assembly comprises a first electrode plate, a second electrode plate, and a conductive member. The first electrode plate includes a first current collector and a first active material layer, and along a winding direction, the first current collector includes a first part and a second part that are connected in sequence. Both surfaces of the first part are arranged with the first active material layer, an inner surface of the second part is provided with the first active material layer, and the second part includes a bending part located at an outermost layer of the first bending section. The conductive member connects the outer surfaces of the first part and the second part, and/or covers on the outer surface of the bending part.