Electrode for non-aqueous electrolyte rechargeable battery, non-aqueous electrolyte rechargeable battery, and battery pack

Abstract

[Problem] To provide a non-aqueous electrolyte rechargeable battery having an excellent retention capacity. An electrode for a non-aqueous electrolyte rechargeable battery of an embodiment of the present invention: has an active material layer, which contains an active material and a fluorine-containing binder, and a current collector that is bound to the active material layer; and, in pyrolysis gas chromatography mass spectrometry at a pyrolysis temperature of (T1 + T2) / 2 DEG C (where T1 DEG C represents the temperature at which pyrolysis of the binding material starts, and T2 DEG C represents the temperature at which pyrolysis ends), a peak exists in an ion chromatogram at any of the mass numbers selected from at least 81, 100, 132 and 200, and, if the peak area at T1 DEG C is denoted as X, and the peak area at T2 DEG C is denoted as Y, X and Y satisfy the condition, 2X>= Y. When the binding material is analyzed by thermogravimetry, the temperature at which pyrolysis of the binding material starts is the temperature at which, in the main weight loss process, there is a 5% loss of weight during the weight loss process. When the binding material is analyzed by thermogravimetry, the temperature at which pyrolysis of the binding material ends is the temperature at which, in the main weight loss process, there is a 95% loss of weight during the weight loss process. The peak area is the area of the peak at the mass number that provides the maximum area among ion chromatographs extracted at mass numbers 81, 100, 132 and 200 in pyrolysis gas chromatography mass spectrometry at a pyrolysis temperature of the binding material alone of (T1 + T2) / 2 DEG C.

Description

technical field [0001] The present invention relates to an electrode for a nonaqueous electrolyte secondary battery, a nonaqueous electrolyte secondary battery and a battery pack. Background technique [0002] Non-aqueous electrolyte secondary batteries represented by lithium-ion secondary batteries have high energy density, so they are used in everything from small portable devices such as personal computers and smartphones to large power supplies such as electric vehicles and power level adjustment power supplies It is used in various fields, but since it is more expensive than aqueous electrolyte secondary batteries such as nickel-hydrogen secondary batteries, it is required to extend its life in order to suppress the exchange frequency. [0003] The reaction mechanism of the deterioration of the non-aqueous electrolyte secondary battery during repeated charge and discharge is not yet clear, but the following reaction mechanism is proposed, for example. [0004] The non-...

AI Technical Summary

Problems solved by technology

The electrode of the non-aqueous electrolyte solution is produced by kneading the active material with the binder material and coating it on the current collector, but in the charged state, the reactivity of the active material is high, and the binder material reacts with the active material, thereby The bonding strength between the active material and the conductive material is weak, and the capacity may decrease

In addition, the binding material is swollen by the organic solvent constituting the non-aqueous electrolyte, and the binding force between the active material and the conductive material decreases, and the capacity may decrease with the increase in resistance.

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