A secondary battery includes a laminate in which a positive electrode, a separator, and a negative electrode are stacked in stated order. Resistance A per unit area of a central region P that has a similar shape to a shape of a surface Z that is either or both of an affixing surface X of the positive electrode and the separator and an affixing surface Y of the negative electrode and the separator, that has a center at the same position as a center of the surface Z, and that has an area equivalent to 10% of area of the surface Z is larger than resistance B per unit area of a region Q other than the central region P at the surface Z.

A secondary battery includes a laminate in which a positive electrode, a separator, and a negative electrode are stacked in stated order. Resistance A per unit area of a central region P that has a similar shape to a shape of a surface Z that is either or both of an affixing surface X of the positive electrode and the separator and an affixing surface Y of the negative electrode and the separator, that has a center at the same position as a center of the surface Z, and that has an area equivalent to 10% of area of the surface Z is larger than resistance B per unit area of a region Q other than the central region P at the surface Z.

A secondary battery includes a jelly roll-type electrode assembly impregnated with an electrolyte solution; a battery case for housing the electrode assembly and the electrolyte solution; a cap assembly coupled with an upper portion of the battery case; and a reference electrode in which one end is immersed with the electrolyte solution and the other end is exposed to the outside through the battery case and the cap assembly.

A secondary battery includes a jelly roll-type electrode assembly impregnated with an electrolyte solution; a battery case for housing the electrode assembly and the electrolyte solution; a cap assembly coupled with an upper portion of the battery case; and a reference electrode in which one end is immersed with the electrolyte solution and the other end is exposed to the outside through the battery case and the cap assembly.

A lithium-ion battery, including a battery cell, an electrolytic solution, and a packaging film. The battery cell is formed by winding a positive electrode plate and a negative electrode plate that are separated by a separator. The lithium-ion battery is half-charged to obtain a half-charged full battery. The half-charged full battery is stripped of the packaging film to obtain a half-charged cell. When a width of the half-charged full battery is w.sub.1, a width of the half-charged cell is w.sub.2, and g=w.sub.2/w.sub.1, the following conditional expression (1) is satisfied: 0.4<g<0.997. A negative active material of the negative electrode plate includes a silicon-based material. When a capacity per unit volume of the negative electrode plate is a, a and g satisfy the following conditional expression (2): 420 mAh/cm.sup.3<g×a<2300 mAh/cm.sup.3, where 619 mAh/cm.sup.3<a<3620 mAh/cm.sup.3. The present invention further provides an electronic device.

A lithium-ion battery, including a battery cell, an electrolytic solution, and a packaging film. The battery cell is formed by winding a positive electrode plate and a negative electrode plate that are separated by a separator. The lithium-ion battery is half-charged to obtain a half-charged full battery. The half-charged full battery is stripped of the packaging film to obtain a half-charged cell. When a width of the half-charged full battery is w.sub.1, a width of the half-charged cell is w.sub.2, and g=w.sub.2/w.sub.1, the following conditional expression (1) is satisfied: 0.4<g<0.997. A negative active material of the negative electrode plate includes a silicon-based material. When a capacity per unit volume of the negative electrode plate is a, a and g satisfy the following conditional expression (2): 420 mAh/cm.sup.3<g×a<2300 mAh/cm.sup.3, where 619 mAh/cm.sup.3<a<3620 mAh/cm.sup.3. The present invention further provides an electronic device.

An electrochemical device includes a negative electrode plate, a positive electrode plate and a separator provided between the negative electrode plate and the positive electrode plate. There are m negative tabs electrically connected to the negative electrode plate, wherein m is a positive integer greater than or equal to 1. There are n positive tabs electrically connected to the positive electrode plate, wherein n is a positive integer greater than 1, and n>m. The electrochemical device is charged with a multi-stage constant current charging method.

Provided is a pouch type secondary battery including a jelly roll in which a plurality of unit cells including a structure of a separator interposed between a positive electrode and a negative electrode are laminated, wherein a unit cell positioned in an outermost layer of the jelly roll includes a carbon dioxide adsorbent.

Provided are a secondary battery and a battery pack including the secondary battery. A sealing plate has a positive electrode terminal attachment hole. A positive electrode terminal penetrates the positive electrode terminal attachment hole. An external conductive member is connected to a portion of the positive electrode terminal located on the battery outer side with respect to the sealing plate. The conduction path between a positive electrode plate and the positive electrode terminal is provided with a current interrupting mechanism. A first insulating member made of resin is disposed between the sealing plate and the positive electrode terminal. A second insulating member having higher thermal resistance than the first insulating member is disposed between the external conductive member and the sealing plate.

An aspect of the present invention is a nonaqueous electrolyte energy storage device that includes a negative electrode including a lithium alloy and a nonaqueous electrolyte containing a fluorinated solvent, in which the lithium alloy contains silver, and the content of silver with respect to the total content of lithium and silver in the lithium alloy is 3% by mass or more and 20% by mass or less. Another aspect of the present invention is a nonaqueous electrolyte energy storage device that includes a negative electrode including a lithium alloy and a nonaqueous electrolyte including a lithium salt containing fluorine, in which the lithium alloy contains silver, and the content of silver with respect to the total content of lithium and silver in the lithium alloy is 3% by mass or more and 20% by mass or less.