A battery pack includes at least one battery cell; a protection circuit module electrically connected to the at least one battery cell; and a thermocompression bonding layer, the thermocompression bonding layer providing a disconnectable electrical connection between an electrode tab of the at least one battery cell and a connection tab of the protection circuit module, wherein the thermocompression bonding layer includes conductive particles and an insulating composite resin layer, the insulating composite resin layer surrounds the conductive particles, and the insulating composite resin layer includes at least one first resin layer and at least one second resin layer, the at least one first resin layer being different from the at least one second resin layer.

A battery pack, includes: a battery cell comprising a main body comprising an electrode assembly, and a terrace part from which electrodes connected to the electrode assembly are drawn out; and a protection module package seated on the terrace part of the battery cell and electrically connected to the battery cell, wherein the protection module package includes: a circuit board includes: a first surface facing the terrace part of the battery cell; a second surface opposite to the first surface; a third surface, which is between the first and second surfaces and faces the main body of the battery cell; and a fourth surface opposite to the third surface and on which a test port is formed; and a connection tab connecting the battery cell to the circuit board.

In one embodiment, a battery includes an exterior unit, an electrode group, an electrode terminal, tab bundles and a lead. The electrode group is housed in an interior cavity of the exterior unit, and the electrode terminal is exposed to an outside. Current collecting tabs are stacked in the thickness direction of the electrode group in each of the tab bundles having the same polarity. The tab bundles protrude from the electrode group to the same side in the length direction of the electrode group. The lead establishes an electric connection between the respective tab bundles and the electrode terminal. The tab bundles are bonded to the lead at positions deviated from one another in the thickness direction, and are mounted on the lead from the same side in the thickness direction.

In one embodiment, a battery includes an exterior unit, an electrode group, an electrode terminal, tab bundles and a lead. The electrode group is housed in an interior cavity of the exterior unit, and the electrode terminal is exposed to an outside. Current collecting tabs are stacked in the thickness direction of the electrode group in each of the tab bundles having the same polarity. The tab bundles protrude from the electrode group to the same side in the length direction of the electrode group. The lead establishes an electric connection between the respective tab bundles and the electrode terminal. The tab bundles are bonded to the lead at positions deviated from one another in the thickness direction, and are mounted on the lead from the same side in the thickness direction.

The present disclosure provides a secondary battery, which comprises an electrode assembly, a pouch, an electrode lead and an insulating tape. The electrode assembly is received in the pouch, the electrode lead is connected with the electrode assembly and extends to the outside of the pouch in a length direction. The electrode assembly comprises electrode plates and a separator, the separator separates the electrode plates. An outer surface of the electrode assembly comprises a first surface and a second surface, an area of the second surface is smaller than an area of the first surface. The first surface is provided as two in number, and the two first surfaces face each other in a thickness direction; the second surface is provided as two in number, and the two second surfaces face each other in a width direction, each second surface connects two first surfaces. At least a part of the insulating tape is provided on the second surface; in the length direction, at least one end of the insulating tape exceeds the electrode plate.

A secondary battery includes a protection module package including a tab bridge, an input/output terminal, and an insulating body that includes a middle block and side block, the middle block having the input/output terminal therein, the side block being spaced apart from the middle block, and the tab bridge connecting the middle block to the side block; and a bare cell including an electrode that is electrically connected to the tab bridge.

A secondary battery configured to effectively estimate the life or degradation of the secondary battery as the secondary battery degrades includes a packaging material, an electrode assembly, a first electrode lead, a second electrode lead, a first measuring lead, and a second measuring lead. The electrode assembly includes a stack having a plurality of first electrode plates at respective first locations within the stack and a plurality of second electrode plates at respective second locations within the stack, the first and second locations alternating with one another and having a separator interposed between each of the first and second locations. The electrode assembly further includes a first measuring plate and a second measuring plate having the same polarity as the first electrode plates and located at at least one of the first locations within the stack.

Provided a battery cell having a plurality of electrodes and a battery module using the same. In order to configure the battery module only by connections of the electrodes without including a separate bus bar and improve the degree of freedom of the connections, the battery cell having cathode terminals and anode terminals protruding to the outside includes: a plurality of electrode terminals selected from the cathode terminals or the anode terminals and formed on both sides of the battery cell opposing each other. The battery cell having the plurality of electrodes and the battery module formed is various forms according to a layout of a vehicle using the same may be configured.

A lithium ion battery and an electric vehicle with the same are provided. The lithium ion battery includes a cover plate assembly and a battery cell assembly, the cover plate assembly includes a pole and a polarity connecting piece, the pole is connected with the polarity connecting piece, the battery cell assembly is provided with a battery cell tab assembly, and the pole is connected and conducted with the battery cell tab assembly through the polarity connecting piece. As a hard connection, the polarity connecting piece is directly or indirectly connected with the battery cell tab assembly. The polarity connecting piece is in interference fit with the pole for laser welding, so that the connection reliability is high, the overcurrent capability is strong, and electronic conduction is easy.

To solve the above problem, a venting device inserted into a sealing part of a pouch of a secondary battery according to the present invention includes: a housing inserted between confronting surfaces of the sealing part and sealed together with the sealing part; an element made of a metal and disposed in the housing and through which a passage is defined providing gas communication between an inside and an outside of the pouch; and a ball disposed at an outlet-side of the passage, the ball configured to open and close the passage, wherein, in the element, an edge of an inner circumference of a surface of the outlet-side of the passage is chamfered or filleted so as to face the ball, and the element includes: a surface treatment layer formed on the chamfered or filleted surface; and a layer made of a polymer and fused to the surface treatment layer.