CN-122000425-A - Battery and lithium ion battery

Abstract

The invention provides a battery capable of inhibiting the generation of cracks of a solid electrolyte layer. The battery includes a positive electrode, a solid electrolyte layer, and a negative electrode in this order along the 1 st direction. In this battery, at least one of the positive electrode and the negative electrode has a plurality of 1 st electrode composite material portions having a cylindrical shape and a plurality of 2 nd electrode composite material portions having a cylindrical shape. The plurality of 1 st electrode composite material portions are arranged on the central portion side of the battery with respect to the plurality of 2 nd electrode composite material portions as viewed from the 1 st direction. And a plurality of 1 st electrode composite material portions, wherein two adjacent electrode composite material portions are arranged at intervals. The diameter of the 1 st electrode composite material portion is smaller than the diameter of the 2 nd electrode composite material portion.

Inventors

• CHAO CANGLIANG
• Haritani Shinya
• HIROSHI NOZAKI

Assignees

• 丰田自动车株式会社

Dates

Publication Date

20260508

Application Date

20251104

Priority Date

20241106

Claims (4)

1. 1. A battery comprising a positive electrode, a solid electrolyte layer and a negative electrode in this order along the 1 st direction, characterized in that, At least one of the positive electrode and the negative electrode has a plurality of 1 st electrode composite material portions having a cylindrical shape and a plurality of 2 nd electrode composite material portions having a cylindrical shape, The plurality of 1 st electrode composite material portions are arranged on the central portion side of the battery with respect to the plurality of 2 nd electrode composite material portions as viewed from the 1 st direction, A plurality of the 1 st electrode composite material portions and adjacent two of the 2 nd electrode composite material portions are arranged at intervals, The diameter of the 1 st electrode composite material portion is smaller than the diameter of the 2 nd electrode composite material portion.
2. 2. The battery of claim 1, wherein the battery is configured to provide the battery with a plurality of cells, The length of the 1 st electrode composite material part in the 1 st direction is the same as the length of the 2 nd electrode composite material part in the 1 st direction, The shortest interval G between the 1 st electrode composite material portion and the 2 nd electrode composite material portion adjacent to the 1 st electrode composite material portion is longer than the length of the 1 st electrode composite material portion in the 1 st direction.
3. 3. The battery of claim 2, wherein the battery is configured to provide the battery with a plurality of cells, The shortest interval G is longer than a length 2 times the expansion amount of the 2 nd electrode composite material portion.
4. 4. A lithium ion battery comprising a positive electrode, a solid electrolyte layer and a negative electrode in this order along the 1 st direction, characterized in that, At least one of the positive electrode and the negative electrode has a plurality of 1 st electrode composite material portions having a cylindrical shape and a plurality of 2 nd electrode composite material portions having a cylindrical shape, The plurality of 1 st electrode composite material portions are arranged on a central portion side of the plurality of 2 nd electrode composite material portions as viewed from the 1 st direction of the lithium ion battery, A plurality of the 1 st electrode composite material portions and adjacent two of the 2 nd electrode composite material portions are arranged at intervals, The diameter of the 1 st electrode composite material portion is smaller than the diameter of the 2 nd electrode composite material portion, The interval is an interval at which two adjacent ones of the 1 st electrode composite material portions and the 2 nd electrode composite material portions are not in contact when the positive electrode or the negative electrode occludes lithium to a near maximum amount.

Description

Battery and lithium ion battery Technical Field The invention relates to a battery and a lithium ion battery. Background In recent years, development of a sulfur battery using sulfur as a positive electrode active material has been advanced. Sulfur has a high theoretical capacity (i.e., 1675 mAh/g). Patent document 1 discloses a positive electrode composite material. The positive electrode composite material contains a positive electrode active material having an S element, a sulfur-containing compound having a P element and an S element, and a conductive auxiliary agent, and does not substantially contain an Li element. The positive electrode composite material has a specific specification value. Patent document 1 Japanese patent application laid-open No. 2019-212615 Disclosure of Invention However, in a battery including a positive electrode composite layer including the positive electrode composite disclosed in patent document 1 and a solid electrolyte layer, stress is easily applied to the solid electrolyte layer due to a volume change (i.e., expansion or contraction) of the positive electrode active material caused by charge or discharge of the battery. As a result, cracks may occur in the solid electrolyte layer. The present invention has been made in view of the above circumstances. An object of an embodiment of the present invention is to provide a battery and a lithium ion battery capable of suppressing the occurrence of cracks in a solid electrolyte layer. Means for solving the above problems include the following embodiments. <1> The battery according to embodiment 1 of the present invention is the following battery: which comprises a positive electrode, a solid electrolyte layer and a negative electrode in this order along the 1 st direction, At least one of the positive electrode and the negative electrode has a plurality of 1 st electrode composite material portions having a cylindrical shape and a plurality of 2 nd electrode composite material portions having a cylindrical shape, The plurality of 1 st electrode composite material portions are arranged on the central portion side of the battery with respect to the plurality of 2 nd electrode composite material portions as viewed from the 1 st direction, A plurality of the 1 st electrode composite material portions and adjacent two of the 2 nd electrode composite material portions are arranged at intervals, The diameter of the 1 st electrode composite material portion is smaller than the diameter of the 2 nd electrode composite material portion. The battery reaction tends to progress more easily in the central portion of the battery as viewed from the 1 st direction than in a portion other than the central portion of the battery. In other words, at least one of the positive electrode composite material portion and the negative electrode composite material portion (hereinafter, also referred to as "composite material portion") in the central portion of the battery tends to have a larger volume change than a portion other than the central portion of the battery. If the volume of the composite material portion in the 2 nd direction changes, stress is generated in the solid electrolyte layer in the 2 nd direction. Since the structure of the embodiment 1 is described above, the stress in the 2 nd direction applied to the solid electrolyte layer accompanying the volume change of the composite material portion is relaxed. As a result, the battery according to embodiment 1 can suppress the occurrence of cracks in the solid electrolyte layer. In addition, in the 1 st aspect, by adjusting the arrangement of the plurality of 1 st electrode composite materials, the volume of the pores that do not participate in the battery reaction can be reduced. Thereby, the energy density of the battery can be improved. <2> The battery according to the 2 nd aspect of the present invention is the battery according to the <1>, wherein, The length of the 1 st electrode composite material part in the 1 st direction is the same as the length of the 2 nd electrode composite material part in the 1 st direction, The shortest interval G between the 1 st electrode composite material portion and the 2 nd electrode composite material portion adjacent to the 1 st electrode composite material portion is longer than the length of the 1 st electrode composite material portion in the 1 st direction. In order to reduce the interfacial resistance of each of the positive electrode, the solid electrolyte layer, and the negative electrode, a restraint pressure is generally applied to the battery in the 1 st direction. By this restraining pressure, the composite material portion may be crushed and deformed (expanded in diameter). Since the structure of the 2 nd aspect has the above-described structure, even if a restraining pressure is applied to the battery, the adjacent two composite material portions are not easily brought into physical contact. As a result, the battery according to claim