Abstract: It is arranged to obtain charging voltage when charging voltage is applied to a nonaqueous electrolyte type lithium ion secondary battery and discharging voltage when a discharging current is generated by the battery. A coefficient of a quadratic term of an approximated curve of a quadratic function with respect to changes in value within a sampling period for each of the charging voltage and the discharging voltage is calculated. This calculation is repeated over a plurality of the sampling periods. Based on occurrence situations of symmetry phenomenon and intersection phenomenon in the calculated coefficients, it can be determined whether or not there is a possibility of lithium deposition without disassembling the battery.

Abstract: The lithium secondary battery provided by the present invention includes a negative electrode having a negative electrode collector and a negative electrode layer including a negative electrode active material and formed on the surface of the negative electrode collector, and is characterized in that the negative electrode layer comprises a negative electrode active material layer composed primarily of a negative electrode active material, and an insulating layer composed primarily of an insulating filler and formed on the negative electrode active material layer, and the ratio (Sb/Sa) of a pore specific surface area of the insulating layer (Sb: m2/g) to a pore specific surface area of the negative electrode active material layer (Sa: m2/g), as measured by a mercury porosimeter, satisfies the relationship 1.2?(Sb/Sa)?2.5.

Abstract: It is arranged to obtain charging voltage when charging voltage is applied to a nonaqueous electrolyte type lithium ion secondary battery and discharging voltage when a discharging current is generated by the battery. A coefficient of a quadratic term of an approximated curve of a quadratic function with respect to changes in value within a sampling period for each of the charging voltage and the discharging voltage is calculated. This calculation is repeated over a plurality of the sampling periods. Based on occurrence situations of symmetry phenomenon and intersection phenomenon in the calculated coefficients, it can be determined whether or not there is a possibility of lithium deposition without disassembling the battery.

Abstract: This invention provides an optical recording material comprising a base and a thin film formed on the base and composed of oxides which are represented by the formula (V.sub.2 O.sub.5).sub.1-x. (M.sub.y O.sub.z).sub.x wherein M.sub.y O.sub.z is at least one of metal oxides, metalloid oxides and non-metal oxides, and 0.ltoreq.x<1 and which have an amorphous or layer structure and a process for preparing an optical recording material, the process comprising the steps of applying to a base a solution, sol solution or gel solution of amorphous oxides represented by the formula (V.sub.2 O.sub.5).sub.1-x.(M.sub.y O.sub.z).sub.x wherein M.sub.y O.sub.z is at least one of metal oxides, metalloid oxides and nonmetal oxides, and 0.ltoreq.x<1, and evaporating off the solvent.

Abstract: This invention provides an amorphous ferromagnetic oxide represented by the formulaA.sub.x.(MmOn).sub.y.(Fe.sub.2 O.sub.3).sub.zwherein A represents at least one of Bi.sub.2 O.sub.3, V.sub.2 O.sub.5, TeO.sub.2 and GeO.sub.2 ; M represents at least one of Mn, Fe, Co, Ni, Cu, Mg, Zn, Cd, Ca, Pb, Ba, Sr and rare earth elements; when M is not a rare earth element, m=1 and n=1; when M is a rare earth element, m=2 and n=3; O<x.ltoreq.80, O<y.ltoreq.60 and 5.ltoreq.z.ltoreq.60 and x+y+z=100, provided that when M is Co, O<x<60, O<y<60 and 40.ltoreq.z.ltoreq.60, and processes for preparing the same.