US-20260128281-A1 - Battery and Manufacturing Method Thereof

US20260128281A1US 20260128281 A1US20260128281 A1US 20260128281A1US-20260128281-A1

Abstract

One embodiment of the present invention provides a secondary battery that can be used in a wide temperature range and is not susceptible to the ambient temperature. In addition, a highly safe secondary battery is provided. The secondary battery is manufactured with the use of three kinds or two kinds of conductive additives without using a binder which is an organic resin. As a carbon material that functions as the conductive additive, graphene oxide, graphene oxide subjected to reduction treatment, or a carbon nanotube is selected.

Inventors

Shunpei Yamazaki
Masayuki Kimura
Taisuke Nakao

Assignees

SEMICONDUCTOR ENERGY LABORATORY CO., LTD.

Dates

Publication Date: 20260507
Application Date: 20231002
Priority Date: 20221007

Claims (8)

1 . A battery comprising: a positive electrode active material layer comprising lithium; and a negative electrode active material layer comprising graphite, silicon, graphene, and a carbon nanotube, wherein the silicon and the graphene are at least partly in contact with each other, and wherein the silicon and the carbon nanotube are at least partly in contact with each other.
2 . The battery according to claim 1 , wherein a content of the silicon included in the negative electrode active material layer is greater than or equal to 7.5 wt % and less than or equal to 37.5 wt %.
3 . The battery according to claim 1 , wherein the negative electrode active material layer comprises a content of a resin material lower than a content of the silicon, or does not comprise a resin material.
4 . The battery according to claim 1 , wherein the negative electrode active material layer further comprises acetylene black.
5 . The battery according to claim 1 , wherein the silicon included in the negative electrode active material layer is nanosilicon.
6 . The battery according to claim 1 , wherein an average particle diameter of positive electrode active material particles included in the positive electrode active material layer is smaller than an average particle diameter of the graphite included in the negative electrode active material layer.
7 . A battery comprising: a positive electrode active material layer comprising lithium; and a negative electrode active material layer comprising graphite, a particle comprising silicon, graphene, and a carbon nanotube, wherein the particle comprising silicon and the graphene are at least partly in contact with each other, and wherein the particle comprising silicon and the carbon nanotube are at least partly in contact with each other.
8 . The battery according to claim 7 , wherein the particle comprising silicon comprises oxygen.

Description

TECHNICAL FIELD One embodiment of the present invention relates to a battery and specifically, relates to a secondary battery. The present invention is not limited to the above field and relates to a semiconductor device, a display device, a light-emitting device, a power storage device, a lighting device, an electronic device, a vehicle, and manufacturing methods thereof. The secondary battery of one embodiment of the present invention can be used as a power supply necessary for the above semiconductor device, display device, light-emitting device, power storage device, lighting device, electronic device, and vehicle. Examples of the above electronic device include an information terminal device provided with the secondary battery. Furthermore, examples of the above power storage device include a stationary power storage device. BACKGROUND ART Among batteries, secondary batteries can be used repeatedly by being charged or discharged, and are also called storage batteries. Secondary batteries using lithium ions as carrier ions, which are called lithium-ion secondary batteries, can have a higher capacity and a smaller size and are under intensive research and development. One of the problems for secondary batteries is their susceptibility to the ambient temperature. For example, a decrease in the ambient temperature leads to a higher viscosity of an electrolyte of a secondary battery, which degrades carrier ion conducting performance. Degraded performance of an electrolyte causes degradation of capabilities, such as an increase in internal resistance, of a secondary battery. Examples of vehicles with motors driven by secondary batteries include electric vehicles; it has been difficult to spread electric vehicles to cold climate areas or tropical regions because of influences of ambient temperatures such as cold temperatures or hot temperatures on an electrolyte. Examples of vehicles including secondary batteries include, in addition to electric vehicles, hybrid vehicles having two power sources of an engine and a motor. Hybrid vehicles include plug-in hybrid vehicles that can be charged from outlets. Examples of electronic devices including secondary batteries include portable information terminals such as mobile phones, smartphones, and laptop personal computers, portable music players, digital cameras, and medical instruments. It is desired that the secondary batteries included in electric vehicles, hybrid vehicles, plug-in hybrid vehicles, or electronic devices can demonstrate stable performance irrespective of the ambient temperature at which the secondary batteries are used. In addition, the secondary batteries are required to be much safer. Patent Document 1 discloses a positive electrode active material layer or a negative electrode active material layer including graphene. REFERENCE Patent Document [Patent Document 1] Japanese Published Patent Application No. 2016-192414 SUMMARY OF THE INVENTION Problems to be Solved by the Invention A lithium-ion secondary battery has a problem in charging and discharging at low temperatures or high temperatures. A secondary battery is a power storage means utilizing a chemical reaction and thus has a difficulty in exhibiting sufficient performance at low temperatures especially below the freezing point. Moreover, at high temperatures, the lifetime of a lithium-ion secondary battery might be shorter and abnormality might occur. A secondary battery that can exhibit stable performance regardless of the ambient temperature in use or storage has been desired. One object of one embodiment of the present invention is to provide a secondary battery that can be used in a wide temperature range and is not susceptible to the ambient temperature. Note that the description of these objects does not preclude the existence of other objects. Note that one embodiment of the present invention does not necessarily achieve all these objects. Note that other objects can be derived from the description of the specification, the drawings, and the claims. Means for Solving the Problems The structure disclosed in this specification is a battery including a positive electrode active material layer including lithium; and a negative electrode active material layer including graphite, silicon, graphene, and a carbon nanotube. The silicon and the graphene are at least partly in contact with each other, and the silicon and the carbon nanotube are at least partly in contact with each other. In this structure, graphite and silicon particles are used as negative electrode active materials. The silicon particles refer to silicon powders that are negative electrode active materials of lithium-ion secondary batteries and have an average grain diameter in particle size distribution, that is, an average particle diameter, of around 100 nm; the silicon particles are referred to as nanosilicon particles in some cases. In order to obtain the silicon particles to be used, it is preferable that a silicon sou