A lead-acid battery is disclosed. The lead-acid storage battery has a container with a cover, the container including one or more compartments. One or more cell elements are provided in the one or more compartments. The one or more cell elements include a positive plate, the positive plate having a positive grid and a positive electrochemically active material on the positive grid; a negative plate, the negative plate having a negative grid and a negative electrochemically active material on the negative grid, wherein the negative electrochemically active material comprises barium sulfate and an organic expander; and a separator between the positive plate and the negative plate. Electrolyte is provided within the container. One or more terminal posts extend, from the cover and are electrically coupled to the one or more cell elements.

A lead-acid battery is disclosed. The lead-acid storage battery has a container with a cover, the container including one or more compartments. One or more cell elements are provided in the one or more compartments. The one or more cell elements include a positive plate, the positive plate having a positive grid and a positive electrochemically active material on the positive grid; a negative plate, the negative plate having a negative grid and a negative electrochemically active material on the negative grid, wherein the negative electrochemically active material comprises barium sulfate and an organic expander; and a separator between the positive plate and the negative plate. Electrolyte is provided within the container. One or more terminal posts extend, from the cover and are electrically coupled to the one or more cell elements.

The present invention relates to a battery cell for evaluating an internal short circuit, and a method for evaluating using the battery cell, wherein an internal short circuit state of a battery cell can be easily induced and, at the same time, an effective internal short circuit evaluation is possible, and the battery cell comprising: first and second electrodes which comprise a coated region on which an electrode mixture layer is coated on a metal current collector and a non-coated region on which an electrode mixture layer is not coated, and which comprise first and second electrode tabs which protrude in one direction from the coated region and do not have an electrode mixture layer coated thereon.

A separator for a rechargeable battery includes a porous substrate and a heat resistance layer on at least one surface of the porous substrate. The heat resistance layer includes an acryl-based copolymer, an alkali metal, and a filler. The acryl-based copolymer includes a unit derived from (meth)acrylate or (meth)acrylic acid, a cyano group-containing unit, and a sulfonate group-containing unit.

A separator for a rechargeable battery includes a porous substrate and a heat resistance layer on at least one surface of the porous substrate. The heat resistance layer includes an acryl-based copolymer, an alkali metal, and a filler. The acryl-based copolymer includes a unit derived from (meth)acrylate or (meth)acrylic acid, a cyano group-containing unit, and a sulfonate group-containing unit.

A heat-resistant separator for an electrochemical element in which the thickness of the separator is reduced while maintaining the balance between the short circuit resistance, resistance, electrolyte impregnation performance, and electrolyte retention performance of the separator. A separator for an electrochemical element includes beaten cellulose fibers, wherein the value obtained by dividing the average value for the distance between the center point of a cellulose stem fiber constituting part of the separator and the center point of another cellulose stem fiber nearest to said cellulose stem fiber by the thickness of the separator is 0.80 to 1.35.

A heat-resistant separator for an electrochemical element in which the thickness of the separator is reduced while maintaining the balance between the short circuit resistance, resistance, electrolyte impregnation performance, and electrolyte retention performance of the separator. A separator for an electrochemical element includes beaten cellulose fibers, wherein the value obtained by dividing the average value for the distance between the center point of a cellulose stem fiber constituting part of the separator and the center point of another cellulose stem fiber nearest to said cellulose stem fiber by the thickness of the separator is 0.80 to 1.35.

A separator includes a substrate and a coating layer on at least one surface of the substrate, wherein the coating layer includes first organic particles and second organic particles, and an average particle diameter of the first organic particles is larger than an average particle diameter of the second organic particles. The first organic particles protrude or extend to a height of about 0.1 μm to about 0.5 μm from a dented portion of a surface of the coating layer, and are distributed on the surface of the coating layer in an area ratio of about 5% or greater to less than 30% with respect to a total surface area of the coating layer. The separator may have improved adhesion to electrodes, insulation characteristics, and air permeability, and a battery including the separator may have improved lifespan characteristics.

A separator includes a substrate and a coating layer on at least one surface of the substrate, wherein the coating layer includes first organic particles and second organic particles, and an average particle diameter of the first organic particles is larger than an average particle diameter of the second organic particles. The first organic particles protrude or extend to a height of about 0.1 μm to about 0.5 μm from a dented portion of a surface of the coating layer, and are distributed on the surface of the coating layer in an area ratio of about 5% or greater to less than 30% with respect to a total surface area of the coating layer. The separator may have improved adhesion to electrodes, insulation characteristics, and air permeability, and a battery including the separator may have improved lifespan characteristics.

An embodiment is directed to a separator with a ceramic-comprising separator layer. The ceramic-comprising separator layer comprises porous metal oxide fibers with diameters in the range from around 3 nm to around 2 microns, aspect ratios in the range from around 20 to around 100,000, and a total open pore volume among the porous metal oxide fibers in the range from around 0.01 cm.sup.3/g to around 1 cm.sup.3/g.