Thin-film batteries having a novel encapsulation system.

An electrochemical cell is provided comprising a thin metal foil packaging made from at least one sheet of metal foil and having a perimeter extending around at least a portion of the electrochemical cell, as well as an electrochemical cell stack contained within the thin metal foil packaging, and a metal-to-metal welded seal around at least a portion of the perimeter of the thin metal foil packaging. The metal-to-metal welded seal is hermetic or nearly hermetic. Furthermore, the metal-to-metal welded seal is narrow, having a width of less than about 1 mm, and is less than about 5 mm away from the electrochemical cell stack. In some embodiments, the thin metal foil packaging functions not only as a hermetically or near hermetically sealed packaging, but also as either the negative or positive current collector, with one electrode of the cell bonded to the foil packaging. A method for making the foregoing electrochemical cell is also provided and involves using laser energy the metal-to-metal welded seal, wherein the laser energy is applied to the foil at high speed using a scanning laser.

An electrochemical cell is provided comprising a thin metal foil packaging made from at least one sheet of metal foil and having a perimeter extending around at least a portion of the electrochemical cell, as well as an electrochemical cell stack contained within the thin metal foil packaging, and a metal-to-metal welded seal around at least a portion of the perimeter of the thin metal foil packaging. The metal-to-metal welded seal is hermetic or nearly hermetic. Furthermore, the metal-to-metal welded seal is narrow, having a width of less than about 1 mm, and is less than about 5 mm away from the electrochemical cell stack. In some embodiments, the thin metal foil packaging functions not only as a hermetically or near hermetically sealed packaging, but also as either the negative or positive current collector, with one electrode of the cell bonded to the foil packaging. A method for making the foregoing electrochemical cell is also provided and involves using laser energy the metal-to-metal welded seal, wherein the laser energy is applied to the foil at high speed using a scanning laser.

A secondary battery includes: an electrode assembly; a case including a bottom part, a pair of side parts integrally formed with the bottom part and bent so as to extend from the bottom part, and a cover part coupled to the pair of side parts to face the bottom part and including a vent, the case accommodating the electrode assembly; and a pair of cap assemblies coupled to open ends of the case to seal the case.

A unit stack-cell structure and an all-solid-state secondary battery including the same, the unit stack-cell structure includes a plurality of stacked unit cells, each unit cell of the plurality of stacked unit cells including a laminate in which a cathode layer; a solid electrolyte layer; an anode layer; and an elastic layer are sequentially arranged, wherein the elastic layer has a compressive strength of greater than or equal to about 0.28 MPa and less than about 0.6 MPa in a compressibility interval in a range of about 40% to about 70%.

A unit stack-cell structure and an all-solid-state secondary battery including the same, the unit stack-cell structure includes a plurality of stacked unit cells, each unit cell of the plurality of stacked unit cells including a laminate in which a cathode layer; a solid electrolyte layer; an anode layer; and an elastic layer are sequentially arranged, wherein the elastic layer has a compressive strength of greater than or equal to about 0.28 MPa and less than about 0.6 MPa in a compressibility interval in a range of about 40% to about 70%.

The present invention provides a nickel-plated heat-treated steel sheet for a battery can (1), having a nickel layer with a nickel amount of 4.4 to 26.7 g/m.sup.2 on a steel sheet (11), wherein when the Fe intensity and the Ni intensity are continuously measured along the depth direction from the surface of the nickel-plated heat-treated steel sheet for a battery can, by using a high frequency glow discharge optical emission spectrometric analyzer, the difference (D2-D1) between the depth (D1) at which the Fe intensity exhibits a first predetermined value and the depth (D2) at which the Ni intensity exhibits a second predetermined value is less than 0.04 μm.

The present invention provides a nickel-plated heat-treated steel sheet for a battery can (1), having a nickel layer with a nickel amount of 4.4 to 26.7 g/m.sup.2 on a steel sheet (11), wherein when the Fe intensity and the Ni intensity are continuously measured along the depth direction from the surface of the nickel-plated heat-treated steel sheet for a battery can, by using a high frequency glow discharge optical emission spectrometric analyzer, the difference (D2-D1) between the depth (D1) at which the Fe intensity exhibits a first predetermined value and the depth (D2) at which the Ni intensity exhibits a second predetermined value is less than 0.04 μm.

A secondary battery includes an outer package member, an electrode terminal, and a battery device. The outer package member has a flat and columnar shape and includes a first bottom part and a second bottom part opposed to each other. The electrode terminal is supported by the first bottom part and is insulated from the first bottom part. The battery device is contained inside the outer package member and includes a first electrode and a second electrode. The first bottom part has a recess around the electrode terminal.

A battery cell is configured such that a jelly-roll type electrode assembly is accommodated in a battery casing, and includes: the battery casing including upper, lower, and side surfaces, wherein the side surface of the battery casing includes an isolation wall providing a buffer space between the battery casing and the electrode assembly. The buffer space accommodates deformation of the electrode assembly when the electrode assembly is expanded, such that deformation of the side surface of the battery casing is prevented from occurring.