Abstract: A battery module 1 includes a group battery 2 in which batteries 30 (31 to 33) are connected in series, and an assessment evaluation unit 3 configured to calculate respective states of health of battery cells 10, in which the group battery 2 includes label elements 20 respectively connected in parallel with the battery cells 10 and configured such that respective impedance characteristics of the batteries 30 differ from one another, and the assessment evaluation unit 3 includes a measurement unit 42 configured to measure a first Cole-Cole plot of the group battery 2, a first calculation unit 44 configured to decompose the first Cole-Cole plot into respective second Cole-Cole plots of the batteries 30, a second calculation unit 44 configured to calculate respective third Cole-Cole plots of the battery cells 10 from the second Cole-Cole plots, and a third calculation unit 45 configured to calculate respective states of the battery cells 10 from the third Cole-Cole plots.

Abstract: A battery module 1 includes a group battery 2 in which batteries 30 (31 to 33) are connected in series, and an assessment evaluation unit 3 configured to calculate respective states of health of battery cells 10, in which the group battery 2 includes label elements 20 respectively connected in parallel with the battery cells 10 and configured such that respective impedance characteristics of the batteries 30 differ from one another, and the assessment evaluation unit 3 includes a measurement unit 42 configured to measure a first Cole-Cole plot of the group battery 2, a first calculation unit 44 configured to decompose the first Cole-Cole plot into respective second Cole-Cole plots of the batteries 30, a second calculation unit 44 configured to calculate respective third Cole-Cole plots of the battery cells 10 from the second Cole-Cole plots, and a third calculation unit 45 configured to calculate respective states of the battery cells 10 from the third Cole-Cole plots.

Abstract: An electrochemical analysis apparatus 1 includes a power controller 20 that generates a rectangular wave signal having a first frequency (f1) and applies the rectangular wave signal to an electrochemical cell 10 including a plurality of electrodes 11 to 13 and an electrolyte 14, a Fourier transform section 30 that Fourier-transforms a response signal of the electrochemical cell 10 to the rectangular wave signal and calculates frequency characteristics including a component of a second frequency f2 of an integer multiple of the first frequency f1, and a calculating section 40 that calculates an impedance characteristic of the electrochemical cell 10 based on the frequency characteristics calculated by the Fourier transform section 30.

Abstract: A battery system includes: a secondary battery; a memory portion that stores information which includes a measurement frequency, a measurement temperature, and an initial limiting capacitance of one secondary battery; a temperature measuring section; a power supply section which applies an AC signal of 0.5 mHz to 10 mHz, to the secondary battery at 40° C. to 70° C.; a measuring portion which measures an impedance of the secondary battery by the AC signal; and a calculating portion that calculates the degree of degradation of the secondary battery.

Abstract: An electrochemical analysis apparatus 1 includes a power controller 20 that generates a rectangular wave signal having a first frequency (f1) and applies the rectangular wave signal to an electrochemical cell 10 including a plurality of electrodes 11 to 13 and an electrolyte 14, a Fourier transform section 30 that Fourier-transforms a response signal of the electrochemical cell 10 to the rectangular wave signal and calculates frequency characteristics including a component of a second frequency f2 of an integer multiple of the first frequency f1, and a calculating section 40 that calculates an impedance characteristic of the electrochemical cell 10 based on the frequency characteristics calculated by the Fourier transform section 30.

Abstract: A battery system includes: a secondary battery; a memory portion that stores information which includes a measurement frequency, a measurement temperature, and an initial limiting capacitance of one secondary battery; a temperature measuring section; a power supply section which applies an AC signal of 0.5 mHz to 10 mHz, to the secondary battery at 40° C. to 70° C.; a measuring portion which measures an impedance of the secondary battery by the AC signal; and a calculating portion that calculates the degree of degradation of the secondary battery.

Abstract: A lithium sulfur secondary battery includes a positive electrode containing a sulfur-based positive electrode active substance, an electrolytic solution, a negative electrode containing a negative electrode active substance that occludes and releases lithium, and a polymeric film that covers a surface of the positive electrode and allows lithium cations to pass but does not allow polysulfide anions to pass.

Abstract: An electrochemical analysis apparatus includes a power controller, a Fourier transform unit, and a calculating unit. The power controller generates a rectangular-wave signal, a first frequency F and a duty ratio D, and applies the signal to an electrochemical cell. The Fourier transform unit performs Fourier transform on first data obtained by sampling a response signal of the cell to calculate a first frequency characteristic including a component of a second frequency integer times as high as the first frequency. The Fourier transform unit performs Fourier transform on second data, a sampling start time of which is (1/F)·D (seconds) different from the first data from which the first frequency characteristic is calculated, to calculate a second frequency characteristic including a component of the second frequency. The calculating unit calculates an impedance characteristic of the cell based on the first frequency characteristic and the second frequency characteristic.

Abstract: A battery system 1 includes a secondary battery 10 including a positive electrode 11, a negative electrode 15, and electrolytes 12 and 14, a storing section 23 configured to store peculiar information of the secondary battery 10 measured in advance including an initial resistance value and an evaluation frequency, a power supply section 20 configured to apply an alternating current signal having the evaluation frequency stored in the storing section 23 to the secondary battery 10, a measuring section 22 configured to measure impedance of a solid electrolyte interphase 17 of the secondary battery 10 from the alternating current signal, and a calculating section 24 configured to calculate at least one of a deterioration degree and a charging depth of the secondary battery 10 from the impedance and the peculiar information.

Abstract: An active material for a lithium secondary battery includes an amorphous and metastable phase which contains silicon, oxygen, and more than 30 at % and 80 at % or less of carbon.