Positive electrode active material for electric device, positive electrode for electric device, and electric device

Abstract

This positive electrode active material for an electric device contains a first active material and a second active material. The first active material comprises a transition metal oxide represented by formula (1): Li1.5[NiaCobMnc[Li]d]O3 (in formula (1), a, b, c, and d satisfy the relationships: 0 < d < 0.5; a + b + c + d = 1.5; and 1.0 < a + b + c < 1.5). The second active material comprises a spinel transition metal oxide that has a crystal structure assigned to the space group Fd-3m and that is represented by formula (2): LiMa'Mn2-a'O4 (in formula (2), M indicates at least one metal element having an atomic valence of 2-4, and a' satisfies the relationship 0 <= a'< 2.0). Also, the fraction content of the first active material and the second active material by mass ratio satisfies the relationship represented by formula (3): 100:0 < MA:MB < 0, MA indicates the mass of the first active material and MB indicates the mass of the second active material).

Description

technical field [0001] The invention relates to positive electrode active materials, positive electrodes for electric devices and electric devices. Specifically, the positive electrode active material of the present invention is generally suitably used as a positive electrode active material of lithium ion secondary batteries and lithium ion capacitors of electric devices. In addition, the electrical device of the present invention is suitably used as an electrical device for vehicles such as electric vehicles, fuel cell vehicles, and hybrid electric vehicles. Background technique [0002] In recent years, in order to cope with air pollution and global warming, it is urgent to reduce carbon dioxide emissions. In the automotive industry, attention is expected to be paid to the reduction of carbon dioxide emissions achieved by the introduction of electric vehicles (EV) and hybrid electric vehicles (HEV). Therefore, development of electric devices such as secondary batteries ...

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Problems solved by technology

However, with Li [Li x Ni y mn ｚ 〕O 2－a The crystal structure of the lithium-nickel-manganese composite oxide shown cannot be stabilized, and there is a problem that a high capacity cannot be maintained.

[0010] In addition, in the studies of the present inventors, even a lithium ion storage battery using the cathode composition for a lithium ion storage battery described in Patent Document 2 has problems such as insufficient discharge capacity, discharge operating voltage, and initial rate characteristics.

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