Provided are an electrolytic solution suitable for a lithium ion secondary battery that includes a positive electrode which has a positive electrode active material having an olivine structure, and includes a negative electrode having graphite as a negative electrode active material, and a superior lithium ion secondary battery having the electrolytic solution. The lithium ion secondary battery includes: a positive electrode that includes a positive electrode active material having an olivine structure; a negative electrode having graphite as a negative electrode active material; and an electrolytic solution. The electrolytic solution contains LiPF.sub.6, a cyclic alkylene carbonate selected from ethylene carbonate and propylene carbonate, methyl propionate, and an additive that starts reductive degradation at a potential higher than a potential at which the above components of the electrolytic solution start reductive degradation.

To suppress heat generation in a stacked battery including a plurality of electric elements in internal short circuits and an unstable reaction when the battery is operated while an energy level is increased, the stacked battery includes a stack comprising a first current collector layer, a second current collector layer, a plurality of bipolar current collector layers that are arranged between the first and second current collector layers at intervals in the stacking direction, a plurality of electric elements, an anode active material layer, and an electrolyte layer that is arranged between the cathode and anode active material layers, where the ratio h/S (cm.sup.−1) of a length h (cm) between the one end face and the other end face in the stacking direction of the stack to an electrode area S (cm.sup.2) on a cross section orthogonal to the stacking direction of the stack is more than 1.

A secondary battery for cycling between a charged and a discharged state, wherein a 2D map of the median vertical position of the first opposing vertical end surface of the electrode active material in the X-Z plane, along the length LE of the electrode active material layer, traces a first vertical end surface plot, EVP1, a 2D map of the median vertical position of the first opposing vertical end surface of the counter-electrode active material layer in the X-Z plane, along the length LC of the counter-electrode active material layer, traces a first vertical end surface plot, CEVP1, wherein for at least 60% of the length Lc of the first counter-electrode active material layer (i) the absolute value of a separation distance, SZ1, between the plots EVP1 and CEVP1 measured in the vertical direction is 1000 μm≥|SZ1|≥5 μm.

A pressure control valve structure includes a wall portion having a plurality of communication holes communicating with the internal space, a plurality of tubular portions surrounding the communication holes and extending outwardly from a wall surface of the wall portion as a proximal end, an elastic valve body disposed in each of the tubular portions and having a first end surface and a second surface opposite from the first surface, an outer peripheral wall surrounding the plurality of tubular portions collectively, and a cover fixed to the outer peripheral wall. The tubular portions are spaced from the cover. The tubular portions has an inner wall surface that includes an inclined surface that is inclined downwardly in a gravity direction from the proximal end of the tubular portion to a distal end of the tubular portion with a compression direction of the elastic valve body set extending horizontally.

Disclosed is a bipolar battery with which thermal deterioration of the electrode body due to the generation of heat of tabs can be suppressed. The bipolar battery of the present disclosure includes a first member, a second member, and a laminate electrode body arranged therebetween, wherein the laminate electrode body includes a first current collector constituting a lamination direction end surface, a second current collector constituting the other lamination direction end surface, at least one bipolar current collector arranged between the first current collector and the second current collector, and a plurality of power generating elements which are electrically connected in series via the bipolar current collector between the first current collector and the second current collector, the first current collector is arranged between the first member and the bipolar current collector, the second current collector is arranged between the second member and the bipolar current collector, the first current collector has a first tab, the second current collector has a second tab, an amount of heat generated by the first tab during energization of the battery is greater than an amount of heat generated by the second tab, the first member is a cooling member for cooling the first current collector, and a cooling performance of the first member is greater than a cooling performance of the second member.

A static battery with a non-conductive elastomeric or thermoplastic housing. The, battery housing is adapted to receive at least one anode assembly, at least one cathode assembly, and at least one bipolar electrode assembly. At least the bipolar electrode assembly is formed from a conductive plastic resin that is formed as a CPE sheet. A carbon material is affixed to the CPE sheet to form the bipolar electrode. The at least one cathode assembly, the at least one anode assembly and the at least one bipolar electrode assembly are received into the battery box such that a liquid, and/or gas seal is formed, between electrode assemblies. The battery housing has slots into which the electrode assemblies are received. When the electrode assemblies are received into the housing, cells are formed by the cooperation of the electrode assemblies and the battery housing. The cells are then filled with electrolyte such as zinc bromide and a lid is placed on the battery box. Once sealed the battery box is a liquid tight container for the battery.

A electric storage device that includes a device body having a first end face that has a first portion and a second portion, and second end face that has a third portion and a fourth portion. The second portion is inclined relative to the first portion, and the fourth portion is inclined relative to the third portion. A first electrode film extends from the first portion to the second portion, and a second electrode film extends from the third portion to the fourth portion.

A fabricating method of a unit structure for accomplishing an electrode assembly formed by a stacking method, and an electrochemical cell including the same are disclosed. The fabricating method of the electrode assembly is characterized with fabricating the unit structure by conducting a first process of laminating and forming a bicell having a first electrode/ separator/ second electrode/ separator/ first electrode structure, conducting a second process of laminating a first separator on one of the first electrode among two of the first electrodes, and conducting a third process of laminating second separator/second electrode one by one on the other first electrode among the two of the first electrodes.

A power storage module comprises: an electrode stacked body including a stacked body in which a plurality of bipolar electrodes are stacked, a pair of terminal electrodes located on an outer side of the stacked body in a stacking direction of the bipolar electrodes, and a plurality of metal plates which constitute the stacked body and the pair of terminal electrodes; and a sealing body provided to surround a side surface of the electrode stacked body. The sealing body includes a plurality of first sealing portions coupled to edge portions of the plurality of metal plates, and a second sealing portion that couples the first sealing portions to each other. A thickness adjustment member that adjusts the thickness of the electrode stacked body in the stacking direction is disposed in the electrode stacked body at a position of overlapping the first sealing portions when viewed from the stacking direction.

A battery is provided which includes a first power generating element, a second power generating element, and a first adhesion layer adhering the first power generating element to the second power generating element. A first positive electrode collector of the first power generating element and a second negative electrode collector of the second power generating element face each other with (i.e., via) the first adhesion layer. Between the first positive electrode collector and the second negative electrode collector, the first adhesion layer is disposed in a region forming a first positive electrode active material layer or a region forming a second negative electrode active material layer, whichever is smaller. The first positive electrode collector and the second negative electrode collector are not in contact with each other in a region in which the first positive electrode active material layer and the second negative electrode active material layer face each other.