Electrochemical device

An electrochemical device, comprising:

• a cell and a shell enclosing the cell;
• wherein the cell comprises a jelly roll comprising a first electrode, a second electrode spaced apart from the first electrode, and a separator disposed between the first electrode and the second electrode, and the first electrode and the second electrode are wound to form the jelly roll;
• the first electrode comprises a first current collector, the first current collector comprises a first surface and a second surface disposed oppositely;
• the first surface faces the shell and comprises a coated region coated with a first active material, and an uncoated region without the first active material;
• the uncoated region comprises a first uncoated region disposed at an end of the jelly roll, and the first uncoated region comprises alternating bent portions and straight portions;
• the bent portions comprise a first bent portion and a second bent portion;
• the first bent portion is a right side of the jelly roll, and the second bent portion is a left side of the jelly roll, the first bent portion and the second bent portion are provided with first insulating layers;
• and
• the straight portions include a first straight portion and a second straight portion, the first straight portion is an upper surface of the jelly roll, and the second straight portion is a lower surface of the jelly roll,
• wherein the bent portions further comprise a third bent portion corresponding to the first bent portion in the first uncoated region;
• and a third insulating layer is in direct contact with the third bent portion and is physically distinct from the separator.