BACKGROUND

The present disclosure generally relates to a positive electrode active material, a positive electrode, a battery, a battery pack, an electronic device, an electric vehicle, a power storage device, and a power system.

Lithium ion secondary batteries characteristically have a higher energy density by use of a higher voltages than the other battery mechanisms, and therefore are popularly applied to mobile information terminals, electric tools, electric automobiles, stationary power storage systems, and the like. On the other hand, various studies have been conducted for the purposes of improving the lithium ion secondary batteries with higher performance and wider applicability. For examples, it has been studied to increase the energy density of a positive electrode active material by increasing a charging voltage or the like, in order to attain a high capacity of a lithium ion secondary battery.

However, such lithium ion secondary battery with a high capacity would have such a drawback that, in case where the lithium ion secondary battery has been repeatedly charged and discharged, capacity deterioration would occur, thereby deteriorating a charging and discharging cycle property. Furthermore, such lithium ion secondary battery would also have such a drawback that a heat-retaining property would deteriorate, that is, the capacity would be deteriorated due to internal resistance increases in a case where the battery is stored in a charged state.

SUMMARY

The present disclosure generally relates to a positive electrode active material, a positive electrode, a battery, a battery pack, an electronic device, an electric vehicle, a power storage device, and a power system.

The conventional technology is not sufficient in a cycle property in a high-temperature environment.

Therefore, an object of the present disclosure is to provide a positive electrode active material, a positive electrode, a battery, a battery pack, an electronic device, an electric vehicle, a power storage device, and a power system, each of which can improve the cycle property and the storage property at a high temperature.

According to an embodiment of the present disclosure, a positive electrode active material is provided. The positive electrode active material includes powder of composite particles including a lithium transition metal composite oxide having a lamellar rock-salt structure and a spinel phase. The spinel phase includes an oxide including lithium and at least a first element X1 selected from the group consisting of magnesium, aluminum, titanium, manganese, yttrium, zirconium, molybdenum, and tungsten, and the lithium transition metal composite oxide mainly includes nickel or cobalt and the first element X1.

According to an embodiment of the present disclosure, a positive electrode of the present disclosure includes a positive electrode active material according to an embodiment as described herein.

According to an embodiment of the present disclosure, a battery of the present disclosure includes the positive electrode having a positive electrode active material according to an embodiment as described herein, a negative electrode, and an electrolyte.

According to an embodiment of the present disclosure, a battery pack of the present disclosure includes the battery as described herein and a controller configured to control the battery.

According to an embodiment of the present disclosure, an electronic device of the present disclosure includes the battery as described herein and the electronic device being configured to receive power supply from the battery.

According to an embodiment of the present disclosure, an electric vehicle of the present disclosure includes the battery as described herein, a converter configured to receive power supply from the battery and convert the power into a driving power for the vehicle; and a controller configured to perform information processing for vehicle control on the basis of information on the battery.

According to an embodiment of the present disclosure, a power storage device of the present disclosure includes the battery as described herein, and the power storage device being configured to provide power supply to an electronic device connected to the battery.

According to an embodiment of the present disclosure, a power system of the present disclosure includes the battery as described herein and the power system being configured to receive power supply from the battery.

According to the present disclosure, an excellent charging and discharging cycle property with high capacity can be attained, while the deterioration during storage can be reduced at the same time. It should be noted that the advantageous effect described herein is not to limit the present invention, and the present invention may have only any one of advantageous effects described in the present disclosure, or may have an advantageous effect different from the advantageous effects described in the present disclosure.

