An electrochemical device, including a housing and N separators. The N separators and the housing together define N+1 accommodating cavities arranged along a first direction. The N+1 accommodating cavities include a first accommodating cavity and a second accommodating cavity adjacent to each other, wherein N2. A first electrode assembly is accommodated in the first accommodating cavity, and a second electrode assembly is accommodated in the second accommodating cavity. The second electrode assembly is far from a reference surface relative to the first electrode assembly. The reference surface is a plane that passes through the 10 center of the electrochemical device along the first direction and is perpendicular to the first direction. The volume V1 of the first accommodating cavity and the volume V2 of the second accommodating cavity satisfy 0.5%(V2V1)/V15%, so that the safety performance of the electrochemical device is improved.

A connection pole for an accumulator, wherein the connection pole includes an inner hollow region configured to receive a pole shaft of the accumulator. The connection pole includes ribs on its inner wall in the inner hollow region, wherein the ribs run in the longitudinal direction of the connection pole and one or more or all of the ribs are integrally formed with the connection pole from the material of the connection pole and protrude from the inner side of the connection pole such that the ribs form a gap between the pole shaft and the inner surface of the connection pole.

A battery structure includes at least one electrode lamination layer, at least one first conductive member and at least one second conductive member. Each electrode lamination layer includes a plurality of first electrode layers, a plurality of second electrode layers and a plurality of insulating layers, wherein each insulating layer is disposed between any immediately-adjacent two of the first electrode layers and second electrode layers. The electrode lamination layer is disposed between the first conductive member and the second conductive member, wherein each first electrode layer or each second electrode layer is electrically connected with and substantially perpendicular to the first conductive member or the second conductive member.

A lithium ion battery cell includes a prismatic casing enclosing active components of the lithium ion battery cell. The lithium ion battery cell also includes a terminal having a terminal post extending through an opening in the casing and electrically connected to the active components; a primary sealing component configured to seal a first portion of the terminal post against the casing; and a secondary seal disposed around a second portion of the terminal post and against the primary sealing component. The secondary seal is formed from a curable adhesive resin and is configured to resist egress of the electrolyte out of the lithium ion battery cell and is configured to resist ingress of moisture into the lithium ion battery cell.

The present secondary battery includes: a first spacer disposed to face a first electrode tab; a second spacer disposed to face the second electrode tab; and an insulating sheet disposed to cover the electrode assembly, the first spacer, and the second spacer, wherein the insulating sheet and the first spacer are connected to each other, and the insulating sheet and the second spacer are connected to each other.

A secondary battery and a secondary battery pack, the secondary battery including a case; an electrode assembly inside the case; a cap plate coupled with the case, the cap plate having an inner side facing an inside of the case and an outer side facing an outside of the case; a flexible collecting tab electrically connected with the electrode assembly and extending through the cap plate from the inner side to the outer side thereof; and, a terminal plate outside of the case and adjacent to the outer side of the cap plate, the flexible collecting tab being electrically connected with the terminal plate.

A single battery includes a casing, a first cover plate, a first terminal, an electrode assembly, and a first insulating member. The casing includes a first opening. The first cover plate seals and is installed on the first opening. The first terminal is installed on the first cover plate. The electrode assembly is arranged in the casing and has a first tab extending from a side close to the first cover plate. The first tab is fixedly connected to the first terminal and is formed with a first tab free end. The first insulating member is installed on a side of the first cover plate close to the electrode assembly. The first insulating member is provided with a tab blocked structure. A side of the first terminal close to the electrode assembly and the tab blocked structure form a first accommodating space.

A single battery includes a casing, a first cover plate, a first terminal, an electrode assembly, and a first insulating member. The casing includes a first opening. The first cover plate seals and is installed on the first opening. The first terminal is installed on the first cover plate. The electrode assembly is arranged in the casing and has a first tab extending from a side close to the first cover plate. The first tab is fixedly connected to the first terminal and is formed with a first tab free end. The first insulating member is installed on a side of the first cover plate close to the electrode assembly. The first insulating member is provided with a tab blocked structure. A side of the first terminal close to the electrode assembly and the tab blocked structure form a first accommodating space.

A battery comprising a cover including a cover main wall and a first cover sidewall extending from the cover main wall at a first substantially perpendicular angle, a base including a base main wall and a first base sidewall extending from the base main wall at a second substantially perpendicular angle, a sidewall structure. A first end of the sidewall structure is coupled against the cover main wall and the first cover sidewall to define a first interior corner therebetween. A second end of the sidewall structure is coupled against the base main wall and the first base sidewall to define a second interior corner therebetween. The first and second interior corners include a substantially zero radius. The cover, the base, the sidewall structure, the first interior corner, and the second interior corner define an interior volume. The battery further comprises a battery cell stack positioned in the interior volume.

A battery comprising a cover including a cover main wall and a first cover sidewall extending from the cover main wall at a first substantially perpendicular angle, a base including a base main wall and a first base sidewall extending from the base main wall at a second substantially perpendicular angle, a sidewall structure. A first end of the sidewall structure is coupled against the cover main wall and the first cover sidewall to define a first interior corner therebetween. A second end of the sidewall structure is coupled against the base main wall and the first base sidewall to define a second interior corner therebetween. The first and second interior corners include a substantially zero radius. The cover, the base, the sidewall structure, the first interior corner, and the second interior corner define an interior volume. The battery further comprises a battery cell stack positioned in the interior volume.