A battery pack includes: a cover plate, a cell module, a first resin layer, a battery pack housing, and at least one first monitoring member. The cell module is accommodated inside the battery pack housing and fastened by the first resin layer, the cover plate is fastened to the battery pack housing, the cell module includes a plurality of cells stacked in a first direction. Each cell includes an electrode assembly, a cell housing configured to accommodate the electrode assembly, and a tab electrically connected to the electrode assembly. The cell housing includes a sealing portion, and the tab extends out of the cell housing from the sealing portion in a second direction. One of the at least one first monitoring member is disposed between sealing portions of the adjacent cells. The first monitoring member is connected to the cell module and monitor temperature of the tab of the cell.

Electrochemical device for storing electrical energy in rectangular geometric cells, narrow stack geometry, according to the above claims wherein for being built from a sturdy housing (4) in the form of a straight rectangular parallelepiped and where hollow metal rods (5) run on the metal substrate (14) of the base (1) and through the through holes (16) of the base (16) and through the through holes (16) of it run hollow metal rods (5) and on each one of them, the positive electrode is inserted followed by a separating element and so on, while the other hollow metal bar (5) is inserted the negative electrode, followed by a separating element and so on forming a “stack” of electrodes (6) which would fit into the base (1) forming the central structure of the device, with the hollow metal rods (5) serving as current collectors. The rectangular narrow stack geometry electrode (6) allows to carry out the pre-metallisation stage necessary to create the SEI, and the subsequent cycle stage in the same device, without reopening it.

Electrochemical device for storing electrical energy in rectangular geometric cells, narrow stack geometry, according to the above claims wherein for being built from a sturdy housing (4) in the form of a straight rectangular parallelepiped and where hollow metal rods (5) run on the metal substrate (14) of the base (1) and through the through holes (16) of the base (16) and through the through holes (16) of it run hollow metal rods (5) and on each one of them, the positive electrode is inserted followed by a separating element and so on, while the other hollow metal bar (5) is inserted the negative electrode, followed by a separating element and so on forming a “stack” of electrodes (6) which would fit into the base (1) forming the central structure of the device, with the hollow metal rods (5) serving as current collectors. The rectangular narrow stack geometry electrode (6) allows to carry out the pre-metallisation stage necessary to create the SEI, and the subsequent cycle stage in the same device, without reopening it.

In one embodiment, a connecting lead connecting between a current collecting tab of an electrode group and an electrode terminal in a battery is provided. The connecting lead includes a top plate portion and a leg portion, a leg portion is bent relative to the top plate portion to one side in a thickness direction of the top plate portion, and a bend line at a bend position to the top plate portion is along a width direction of the top plate portion. The leg portion includes an extension portion located apart from the bend position to the top plate portion. The extension portion includes, on an outer surface, a side face relaying between a pair of main faces and facing one side in the width direction of the top plate portion. The side face is joined to the current collecting tab.

An electrochemical device includes a packaging shell having a first packaging body provided with a first dent and a first flange connected to a sidewall of the first dent, and a second packaging body provided with a second dent and a second flange connected to a sidewall of the second dent; a first electrode assembly disposed in the first dent; a second electrode assembly disposed in the second dent; and a partition plate including a partition layer and a first bonding layer located on a first surface of the partition layer. The partition plate is located between the first packaging body and the second packaging body. The flange overlaps the partition plate and extends beyond an edge of the partition plate. The partition plate fits with the first packaging body and the second packaging body to form mutually independent cavities on two sides of the partition plate.

An electrochemical device includes a packaging shell having a first packaging body provided with a first dent and a first flange connected to a sidewall of the first dent, and a second packaging body provided with a second dent and a second flange connected to a sidewall of the second dent; a first electrode assembly disposed in the first dent; a second electrode assembly disposed in the second dent; and a partition plate including a partition layer and a first bonding layer located on a first surface of the partition layer. The partition plate is located between the first packaging body and the second packaging body. The flange overlaps the partition plate and extends beyond an edge of the partition plate. The partition plate fits with the first packaging body and the second packaging body to form mutually independent cavities on two sides of the partition plate.

W1/T1 is equal to or greater than 5, assuming that the width of an electrode body in a direction perpendicular to a winding axis direction and a thickness direction of the electrode body is W1 (mm) and the thickness of the electrode body 3 is T1 (mm).

W1/T1 is equal to or greater than 5, assuming that the width of an electrode body in a direction perpendicular to a winding axis direction and a thickness direction of the electrode body is W1 (mm) and the thickness of the electrode body 3 is T1 (mm).

An electrochemical device includes a negative electrode plate, a positive electrode plate and a separator provided between the negative electrode plate and the positive electrode plate. There are m negative tabs electrically connected to the negative electrode plate, wherein m is a positive integer greater than or equal to 1. There are n positive tabs electrically connected to the positive electrode plate, wherein n is a positive integer greater than 1, and n>m. The electrochemical device is charged with a multi-stage constant current charging method.

An electrochemical device includes a negative electrode plate, a positive electrode plate and a separator provided between the negative electrode plate and the positive electrode plate. There are m negative tabs electrically connected to the negative electrode plate, wherein m is a positive integer greater than or equal to 1. There are n positive tabs electrically connected to the positive electrode plate, wherein n is a positive integer greater than 1, and n>m. The electrochemical device is charged with a multi-stage constant current charging method.