This power storage system is provided with a secondary cell pack and a system protection unit having a system protection function of cutting off the secondary cell pack from the outside of the power storage system. This secondary cell pack is provided with a secondary cell and a cell protection unit having a cell protection function of cutting off the secondary cell from the outside of the secondary cell pack. The cell protection unit further monitors a state value that indicates the state of the secondary cell and controls implementation of the system protection function and the cell protection function on the basis of the state value.

A battery includes a case, first and second electrodes in the case, and a switch to change an electrical state of the case between a first state and a second state, when the first state corresponds to an electrically neutral state and the second state corresponds to an electrical polarity of the first electrode. The switch may reciprocally change the electrical state of the case between the first state and the second state.

A cylindrical nonaqueous electrolyte secondary battery having an electrode body which includes a negative electrode having a negative electrode active material, and the negative electrode active material contains a compound containing silicon (Si); a sealing body which has a current cutoff mechanism which includes an upper valve body and a lower valve body disposed below the upper valve body to be connected to the upper valve body, and in which when the gas pressure in a space formed between the upper valve body and the lower valve body is increased, a current path is cut off; and a bottom portion of the case body has a thin portion which forms at least a portion of a ring, and the thickness t of a portion deviating from the thin portion of the bottom portion is 0.25 mm<t<0.35 mm.

The present disclosure is directed to a convertible battery pack having an improved switching circuit. The switching circuit includes a converter element having a plurality of contacts positioned in the converter element such that as the converter element slides within the battery pack the contacts move from a first position to engage a first set of contact pads to a second position to engage a second set of contact pads. The converter element includes a pair of springs for each of the plurality of contacts that force the contacts into engagement with the contact pads but also allow the contacts to adjust for imperfections in the contact pad surface or the manufacturing tolerances of the contact pads or a support board that holds the contact pads.

A high voltage battery for vehicles includes an anode tab that is divided into a first part placed near a battery cell and a second part placed near a terminal. A first part extension extends from the first part and is fixed to a lower pouch. A second part extension extends from the second part, comes into contact with the first part extension, and is fixed at an upper end thereof to an upper pouch. An cathode extension extends from a cathode tab and is spaced apart from the upper end of the second part extension. A cushion is interposed between the second part extension and the cathode extension, with a reference level of pressure formed in the cushion.

A connecting element for at least two energy storage cells, having a metal sheet for the electrical connection of the energy storage cells. The metal sheet has at least two perforations for the uptake in each perforation of at least a part of an energy storage cell. Two lugs provided on the metal sheet project into the perforations.

A battery includes a bottomed cylindrical case body that accommodates an electrode body and a bottom-portion insulating plate (19) that is disposed between the electrode body and a bottom portion of the case body. The bottom portion of the case body has a gas discharge port that opens when an internal pressure of the battery reaches a predetermined pressure. The bottom-portion insulating plate (19) has a through hole. An aperture ratio, which is a ratio of an area of the through hole with respect to a total area of the insulating plate, is greater than or equal to 10% and less than or equal to 40%. A Young's modulus of the bottom-portion insulating plate at 25° C. is 10 GPa or greater.

A battery holder containing 2 or more batteries connected to allow multiple voltage outputs. Each output being protected by an automatically resettable circuit to limit maximum current under all possible external connections and sound an alarm or produce a visual indication or both if any output current is exceeded. Protection and alarm are designed to sense current levels and work in holders with weak batteries, alkaline cells, mercury cells, lithium cells, rechargeable cells, and any cell with voltage greater than 1 volt. Protection and alarm will also work when battery holder has some batteries not installed. Protection circuits are not part of the batteries and remain with the battery holder when batteries are changed.

A thin film battery package includes: a case having an open top side and defining a predetermined space therein, wherein the case has one side at which first and second electrodes formed of a metal material are exposed and electrically connected to the outside; a battery block on which a plurality of unit batteries are stacked so that the plurality of unit batteries is electrically connected between a first terminal and a second terminal, wherein the battery block is seated within the case so that the first and second terminals of the unit battery disposed at one end thereof are electrically connected to the first and second electrodes; and a cover sealed and coupled to the top surface of the case.

A battery management system for a battery module having at least one battery cell provides a current path between poles of the battery module in response to a tripping signal. The current path prevents or terminates an arc in a fuse of the at least one battery cell after the fuse has been tripped. The battery management system can further include an apparatus to trip the fuse and provide the tripping signal in response to identifying the tripping of the at least one fuse. The battery management system can further include an apparatus to receive the tripping signal.