A secondary battery includes an opening portion provided to a case. A first sealing body is provided to the opening portion, the first sealing body being displaced or deformed by a pressure difference between an inside and an outside of the case in such manners that the first sealing body is pressed by internal pressure to allow outflow of inside air from the opening portion when the internal pressure in the case is higher than external pressure and that the first sealing body is pressed by the external pressure to prevent entry of outside air from the opening portion when the internal pressure in the case is lower than the external pressure. Pressure in a space surrounded with the case and the first sealing body is set to be lower than pressure outside the space.

A lead-acid battery (100) is provided with a lid (14). An external flow passage (530) communicating with a communication chamber (520) through a vent hole (321) and communicating with a discharge port (405) of a lid (14) is formed inside the lid (14). A compartment fence (452, 454) continuously extending over the entire width of the external flow passage (530) is formed in the external flow passage (530). A residual volume is larger than the volume of the communication chamber (520), the residual volume being obtained by subtracting, from the total volume of a plurality of external spaces (460, 462, 464) divided by the compartment fence (452, 454), the volume of the discharge-side external space (464) closest to the discharge port among the plurality of external spaces.

A battery pack prevents an inflow of a leaking coolant. The battery pack includes a housing, in which at least one battery cell or battery module is mounted, a heat exchanger provided in the housing for cooling the battery cell or the battery module, and seal provided between the heat exchanger and the inner surface of the housing for preventing coolant leaking from the heat exchanger from flowing into a space in which the battery cell or the battery module is placed, whereby the stability and reliability of the battery pack are improved.

A battery includes a metal battery can that has a tubular portion having an opening edge portion at one end of the tubular portion and a bottom portion closing the other end of the tubular portion; an electrode body that is accommodated in the battery can; an electrolytic solution that fills the battery can; and a sealing member that has an outer peripheral surface disposed to face an inner peripheral surface of the opening edge portion of the tubular portion and seals the opening edge portion, in which a part of the inner peripheral surface of the opening edge portion and a part of the outer peripheral surface of the sealing member are joined by a melting portion, and a preventing portion, which prevents the electrolytic solution from rising toward a position, in which the melting portion is formed, between the inner peripheral surface of the opening edge portion and the outer peripheral surface of the sealing member, is provided on the outer peripheral surface of the sealing member, the preventing portion being closer to the bottom portion than the melting portion is.

Provided is an ampoule-type reserve battery including: an ampoule casing having an accommodation part formed therein; an electrolyte accommodated in a lower portion of the accommodation part; a leakage prevention liquid made of oil, which is phase-separated from the electrolyte without being mixed therewith so as to prevent the electrolyte from leaking through an upper portion of the accommodation part, and accommodated in the upper portion of the accommodation part; and a separation membrane mounted in the accommodation part and configured to separate the electrolyte from the leakage prevention liquid.

The present disclosure relates to an end cover assembly, a battery cell, a battery pack and a device. The end cover assembly includes a cover assembly, a terminal assembly, a sealing piece and a first connected flow channel. The cover assembly is provided with an installation hole, and the installation hole penetrates through the cover assembly along an axial direction of the installation hole; the terminal assembly is installed in the installation hole; the sealing piece is configured to seal the installation hole; the first connected flow channel is arranged in at least one of the terminal assembly and the cover assembly, and the first connected flow channel is configured as follows: when the sealing of the sealing piece is invalid, the first connected flow channel enables the inside and the outside of the housing to be communicated through the installation hole.

A manufacturing method for a secondary battery and a manufacturing apparatus for a secondary battery that are applicable to a secondary battery in which an electrolyte solution injection hole has a diameter of 1.5 mm or more are provided. The secondary battery includes a battery case including a cover plate provided with an electrolyte solution injection hole, and a sealing member sealing the electrolyte solution injection hole. The manufacturing method includes a preparing step and a press-fitting step. The preparing step is preparing a cell in which, after an electrolyte solution is injected to the battery case through the electrolyte solution injection hole, the sealing member is disposed on the electrolyte solution injection hole. The press-fitting step is press-fitting the sealing member into the electrolyte solution injection hole while applying press-fitting load and ultrasonic vibration with a frequency of 20 kHz or more in parallel to a press-fitting direction.

A power storage device includes: a power storage module in which an electrolytic solution is accommodated, the power storage module including a top face, a bottom face, and a plurality of side faces provided such that the side faces connect the top face to the bottom face; a liquid discharge valve provided on at least one of the side faces; a liquid collection unit configured to collect the electrolytic solution discharged from the liquid discharge valve; an accumulation portion in which the electrolytic solution collected by the liquid collection unit is accumulated; a corrosion portion configured to corrode due to the electrolytic solution; and a detection portion configured to detect breakage of the corrosion portion. The corrosion portion is placed in a passage route along which the electrolytic solution collected by the liquid collection unit reaches the accumulation portion.

A battery includes a metal battery can that has a tubular portion having an opening edge portion and a bottom portion; an electrode body that is in the battery can; an electrolytic solution that fills the battery can; and a sealing member that has an outer peripheral surface facing an inner peripheral surface of the opening edge portion of the tubular portion and is configured to seal the opening edge portion. A part of the inner peripheral surface of the opening edge portion and a part of the outer peripheral surface of the sealing member are joined by a melting portion, and a preventing portion is on the outer peripheral surface of the sealing member, the preventing portion being configured to prevent the electrolytic solution from rising toward a position, in which the melting portion is formed.

A lead-acid battery is provided with a lid. A communication chamber is formed inside the lid. In the communication chamber, a first distance between an inner wall and a vent hole in a sidewall is shorter than a second distance between the inner wall and an exhaust hole, and a tip of the inner wall is formed below the vent hole in a direction opposite to the first direction.