Abstract: A method of producing a secondary battery disclosed here includes forming a positive electrode active material layer containing a lithium- and manganese-containing composite oxide on a positive electrode current collector to produce a positive electrode; measuring a peel strength between the positive electrode active material layer and the positive electrode current collector; producing a secondary battery assembly including the positive electrode, a negative electrode, and a nonaqueous electrolyte using the positive electrode; and initially charging the secondary battery assembly. When the secondary battery assembly is initially charged, a charging rate is determined based on the measured peel strength, and in a predetermined peel strength range, a lower charging rate is set for a secondary battery assembly including a positive electrode having a low peel strength than for a secondary battery assembly including a positive electrode having a large peel strength.

Abstract: The present invention provides a positive electrode material for lithium secondary batteries, having: a positive electrode active material containing Li; and a cover disposed on the positive electrode active material, and containing Li and F, and further containing one or two or more cover elements from among Al, Ti, Zr, Ta and Nb. With a Point a as an arbitrary point of the cover in contact with the positive electrode active material, a Point c as a point on the surface of the cover at a shortest distance from the Point a, and a Point b as a midpoint between the Point a and the Point c, an analysis of the Point a, the Point b and the Point c by X-ray photoelectron spectroscopy yields a ratio of Li concentration at the Point a with respect to the Li concentration at the Point b is 1.1 or higher and lower than 10.8, and a ratio of F concentration at the Point c with respect to F concentration at the Point b is 1.1 or higher and lower than 51.1.

Abstract: A method of producing a secondary battery disclosed here includes forming a positive electrode active material layer containing a lithium- and manganese-containing composite oxide on a positive electrode current collector to produce a positive electrode; measuring a peel strength between the positive electrode active material layer and the positive electrode current collector; producing a secondary battery assembly including the positive electrode, a negative electrode, and a nonaqueous electrolyte using the positive electrode; and initially charging the secondary battery assembly. When the secondary battery assembly is initially charged, a charging rate is determined based on the measured peel strength, and in a predetermined peel strength range, a lower charging rate is set for a secondary battery assembly including a positive electrode having a low peel strength than for a secondary battery assembly including a positive electrode having a large peel strength.

Abstract: Provided is an oil separator built-in compressor, which prevents a drop in the separating ability of an oil separator while reducing a pressure loss in a communication hole formed between a discharge chamber and an oil separation chamber and which also considers the working feasibility of a casing. The oil separator built-in compressor comprises: a separation chamber arranged adjacent to the discharge chamber and formed entirely thereof into a space in order to separate an oil-containing gas being introduced, centrifugally into gas and oil so that the separated oil flows downward whereas the separated gas is released upward; and the communication hole formed between the discharge chamber and the separation chamber in order to introduce the oil-containing gas from the discharge chamber into the separation chamber.