A secondary battery includes a current interrupt device (CID), a safety vent disposed on the current interrupt device and electrically connected to the current interrupt device, and a CID gasket for surrounding an edge of the current interrupt device. The CID gasket includes reinforcement material, and the reinforcement material includes at least one of glass fiber, carbon fiber, aramid fiber, cellulose, ceramic particles, and a filler.

An overcharge protection device cover assembly for use with a battery cell housing. The battery cell housing has a first terminal and a second terminal, the overcharge protection device cover assembly including a first terminal pad having a first length. The first terminal pad is contactable with the first terminal of the battery cell housing. The assembly also includes a second terminal pad having a second length that is greater than the first length. The second terminal pad is contactable with the second terminal of the battery cell housing. A reversal device of the assembly is deflectable toward the first and second terminal pads. A conductive element of the assembly is positioned between the reversal device and the first and second terminal pads.

An overcharge protection device cover assembly for use with a battery cell housing. The battery cell housing has a first terminal and a second terminal, the overcharge protection device cover assembly including a first terminal pad having a first length. The first terminal pad is contactable with the first terminal of the battery cell housing. The assembly also includes a second terminal pad having a second length that is greater than the first length. The second terminal pad is contactable with the second terminal of the battery cell housing. A reversal device of the assembly is deflectable toward the first and second terminal pads. A conductive element of the assembly is positioned between the reversal device and the first and second terminal pads.

The present disclosure provides a secondary battery configured such that an electrode assembly including a positive electrode, a separator, and a negative electrode is housed in a battery case together with an electrolyte solution, wherein the battery case is made of metal, and a conductive layer made of one selected from the group consisting of a conductive carbon layer, a conductive polymer layer, and a conductive epoxy layer is formed on a part or the whole of the inner surface of the battery case coming into contact with the electrolyte solution.

Various embodiments of the present invention pertain to a secondary battery, and a technical problem thereof to be solved is providing a secondary battery that is capable of equalizing internal/external pressure. To this end, disclosed in the present invention is a secondary battery comprising: an electrode assembly; a case that accommodates the electrode assembly; a cap plate that seals the case, and that has a safety vent that is ruptured when internal pressure of the case rises; a terminal portion that is electrically connected to the electrode assembly, and that extends outwardly from the cap plate; and a pressure equalization structure that is formed on the cap plate so as to equalize the internal pressure and external pressure of the case.

Various embodiments of the present invention pertain to a secondary battery, and a technical problem thereof to be solved is providing a secondary battery that is capable of equalizing internal/external pressure. To this end, disclosed in the present invention is a secondary battery comprising: an electrode assembly; a case that accommodates the electrode assembly; a cap plate that seals the case, and that has a safety vent that is ruptured when internal pressure of the case rises; a terminal portion that is electrically connected to the electrode assembly, and that extends outwardly from the cap plate; and a pressure equalization structure that is formed on the cap plate so as to equalize the internal pressure and external pressure of the case.

The present disclosure provides a cap assembly for a secondary battery, a secondary battery and a battery module. The cap assembly for the secondary battery includes a cap plate, a first electrode terminal, and a sealing member, wherein: the cap plate has an electrode lead-out hole; the first electrode terminal includes a first terminal board and a second terminal board connected with the first terminal board, wherein the first terminal board is located at a side of the second terminal board away from the cap plate, the second terminal board covers the electrode lead-out hole, and the material of the first terminal board and the material of the second terminal board have different base metals; the sealing member surrounds the electrode lead-out hole and is disposed between the cap plate and the first electrode terminal to seal the electrode lead-out hole.

The present disclosure provides a cap assembly for a secondary battery, a secondary battery and a battery module. The cap assembly for the secondary battery includes a cap plate, a first electrode terminal, and a sealing member, wherein: the cap plate has an electrode lead-out hole; the first electrode terminal includes a first terminal board and a second terminal board connected with the first terminal board, wherein the first terminal board is located at a side of the second terminal board away from the cap plate, the second terminal board covers the electrode lead-out hole, and the material of the first terminal board and the material of the second terminal board have different base metals; the sealing member surrounds the electrode lead-out hole and is disposed between the cap plate and the first electrode terminal to seal the electrode lead-out hole.

A cover assembly of a secondary battery. The cover assembly includes: a cover plate including a gas vent; a gas exhaust valve configured to seal the gas vent and deform in response to an increase in temperature to get out of a state of sealing the gas vent; and a sealing part arranged between the gas exhaust valve and the cover plate and surrounding the gas vent for sealing a gap between the gas exhaust valve and the cover plate.

A cover assembly of a secondary battery. The cover assembly includes: a cover plate including a gas vent; a gas exhaust valve configured to seal the gas vent and deform in response to an increase in temperature to get out of a state of sealing the gas vent; and a sealing part arranged between the gas exhaust valve and the cover plate and surrounding the gas vent for sealing a gap between the gas exhaust valve and the cover plate.