This application provides a top cover of a power battery and a power battery, the top cover includes a top cover sheet, a first electrode unit and a second electrode unit, the first electrode unit includes a turning sheet, an insulating piece and a current cutting-off structure, the current cutting-off structure is fixed in radial projection range of an assembling hole and is electrically connected with the top cover sheet, the turning sheet is fixed at an underneath of the top cover sheet through the insulating piece, the turning sheet is electrically connected with the top cover sheet merely through the current cutting-off structure, and the turning sheet is capable of turning and breaking the current cutting-off structure when an internal pressure of the power battery exceeds a reference pressure, so as to cut off an electrical connection of the current cutting-off structure with the top cover sheet.

Provided is an all-solid-state lithium battery including an oriented positive electrode plate composed of an oriented polycrystalline body made of lithium transition metal oxide grains, a solid electrolyte layer, a negative electrode layer, and an end insulator insulating and coating ends of the oriented positive electrode plate. The surface of the end insulator and the surface of the oriented positive electrode plate adjacent the solid electrolyte layer form one continuous surface no step exists. Alternatively, the height of the surface of the end insulator adjacent the solid electrolyte layer is lower than that of the surface of the oriented positive electrode plate adjacent the solid electrolyte layer to form a discontinuous surface with proviso that a step between the end insulator and the surface of the oriented positive electrode plate adjacent the solid electrolyte layer is smaller than the thickness of the solid electrolyte layer.

Provided is a lithium ion secondary battery which has a low internal resistance in a low-SOC region and a sufficiently large amount of gas generated during overcharge. The lithium ion secondary battery disclosed herein includes an electrode body having a positive electrode and a negative electrode, and a nonaqueous electrolytic solution. The lithium ion secondary battery further includes a pressure-type safety mechanism. The nonaqueous electrolytic solution includes a gas generating agent. The positive electrode has a positive electrode active material layer including a positive electrode active material. The positive electrode active material includes a lithium transition metal composite oxide represented by LiNi.sub.aCo.sub.bMn.sub.cO.sub.2 wherein a, b and c satisfy the following conditions: 0.35≦a≦0.45, 0.15≦b≦0.25, 0.35≦c≦0.45, and a+b+c=1, and a lithium transition metal composite oxide represented by LiNi.sub.xCo.sub.yMn.sub.zO.sub.2 wherein x, y and z satisfy the following conditions: 0.35≦x≦0.45, 0.45≦y≦0.55, 0.05≦z≦0.15, and x+y+z=1, and the mass ratio of the oxides is 60:40 to 85:15.

A double-sealed thin film electrochemical pouch cell, comprising a cathode current collector, a cathode, an electrolyte, an anode, and an anode current collector, which is double-sealed by a first inner laminate layer forming a primary seal covered by a second outer polymer layer forming a secondary seal. The second outer polymer layer comprises embedded particles to increase the thermal conductivity of the second outer polymer layer.

Disclosed herein is a battery pack which includes a plurality of battery modules housed in a housing. The battery modules are connected in series to each other via connecting members that connects external terminals of the battery modules to each other. The battery modules are classified into groups, each being comprised of at least two of the battery modules, two terminal ones of which have a potential difference of at most V or less between themselves. A first connecting member connects the external terminals of the battery modules to each other between two adjacent ones of the groups. A second connecting member connects the external terminals of the battery modules to each other within an identical one of the groups. If water penetrates into the housing, the first connecting member is electrically cut off, preferentially relative to the second connecting member.

A secondary battery includes a first electrode plate and a second electrode plate, a case accommodating the electrode plates, and a cap assembly to seal the case. The cap assembly has a short-circuit hole and a cap plate electrically connected to the first electrode plate. The battery also includes an inversion plate spaced from a short-circuit plate. The inversion plate is positioned in or over the short-circuit hole and bent toward the case. The short-circuit plate is electrically connected to the second electrode plate. When an internal pressure of the battery exceeds a value, the inversion plate moves to contact the short-circuit plate, which, in turn, breaks a fuse. A groove is included in the gap assembly adjacent the short-circuit plate. When the inversion plate moves under excessive pressure, an edge portion of the gap assembly deforms away from the short-circuit plate.

A battery pack assembly includes a first battery cell supplying electric current to an electronic load, a second battery cell supplying electric current to the electronic load, and a first switch operatively coupled with the first battery cell and the electronic load. The first switch stops conduction of the electric current to the electronic load responsive to an increase in electric demand of the electronic load above a designated threshold. A method of powering an electronic load using a battery pack assembly also is provided.

A high energy density rechargeable (HEDR) battery employs a combined current limiter/current interrupter to prevent thermal runaway in the event of internal discharge or other disruption of the separator. The combined current limiter/current interrupter is interior to the battery.

According to one embodiment, a nonaqueous electrolyte secondary battery includes a positive electrode, a negative electrode, and a nonaqueous electrolyte. The negative electrode includes a negative electrode current collector and a negative electrode mixed-material layer on the negative electrode current collector. The negative electrode mixed-material layer includes a titanium-containing metal oxide and a binder including an acrylic resin. The negative electrode satisfies α/β>1.36×10.sup.−2, where “α” is a peel strength (N/m) between the current collector and the negative electrode mixed-material layer, and “β” is a cutting strength (N/m) according to a surface and interfacial cutting method in the negative electrode mixed-material layer.

The battery pack includes a battery cell for supplying electric power to an external device connected thereto, a temperature sensor for sensing a temperature of a place on which the temperature sensor is arranged, a switch member for making and breaking an electric path between the external device and the battery cell; and a controller configured to control the switch member to turn on and off according to the temperature sensed by the temperature sense. The temperature sensor is arranged on a position between the battery cell and the switch member so as to be affected by the temperatures of both of the battery cell and the switch member.