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WO-2026091473-A1 - BATTERY CASE, BATTERY COMPRISING CASE, AND ELECTRIC DEVICE COMPRISING BATTERY

WO2026091473A1WO 2026091473 A1WO2026091473 A1WO 2026091473A1WO-2026091473-A1

Abstract

The present application relates to the technical field of batteries, and more specifically to a battery case, a battery comprising the case, and an electric device comprising the battery. The material of the case comprises steel, and the components of the steel include Ti, Nb and Cr. Based on the total mass of the steel, the mass percentage content of Cr is greater than or equal to 16 wt.%. The case comprises a side wall and an end wall integrally formed with the side wall. The case satisfies the following relational expression: 50≤(h/d)/(b+c)≤7000, wherein h is the height of the case, in mm; d is the thickness of the end wall, in mm; b is the mass percentage content of Ti based on the total mass of the steel, in wt.%; and c is the mass percentage content of Nb based on the total mass of the steel, in wt.%. In the present application, by controlling the relationship between the Ti and Nb contents and the height and end wall thickness of the case, the steel with such Ti and Nb contents can meet the deep‑drawing performance requirements of the battery case, and the formed case has good pressure-bearing capacity.

Inventors

  • LIU, Congyi
  • QI, Binwei
  • DU, Guoyi

Assignees

  • 中创新航科技集团股份有限公司

Dates

Publication Date
20260507
Application Date
20250514
Priority Date
20241104

Claims (20)

  1. A battery casing (1) is made of steel, characterized in that the steel comprises Ti, Nb and Cr, wherein the mass percentage of Cr is ≥16 wt.% based on the total mass of the steel; The housing (1) includes a side wall (13) and an end wall (11) integrally formed with the side wall (13); The shell (1) satisfies the following relationship: 50≤(h/d)/(b+c)≤7000; Where h is the height of shell (1), in mm; d is the thickness of the end wall (11), in mm; b represents the mass percentage of Ti based on the total mass of the steel, expressed in wt.%. c represents the mass percentage of Nb based on the total mass of steel, expressed in wt.%.
  2. According to claim 1, the battery casing is characterized in that the casing (1) satisfies the following relationship: 142≤(h/d)/(b+c)≤2000.
  3. The battery casing according to claim 1 or 2 is characterized in that the range of h is 20-300 mm.
  4. According to claim 3, the battery casing is characterized in that the range of h is 50-270 mm.
  5. The battery casing according to claim 1 or 2, wherein the range of d is 0.2-1.5 mm.
  6. According to claim 5, the battery casing is characterized in that the range of d is 0.5-1.0 mm.
  7. The battery casing according to claim 1, wherein the range of b+c is 0.2-0.8 wt.%.
  8. The battery casing according to claim 7, wherein the range of b+c is 0.25-0.5 wt.%.
  9. The battery casing according to claim 7, wherein the range of b is 0.05-0.2 wt.%.
  10. The battery casing according to claim 7, wherein the range of c is 0.17-0.5 wt.%.
  11. According to claim 1, the battery casing is characterized in that the casing (1) also satisfies the following relationship: 0.5≤(f/d)/(b+c)≤5, where f is the thickness of the side wall (13) of the casing (1) in mm.
  12. According to claim 11, the battery casing is characterized in that the range of f is 0.1-1.2 mm.
  13. According to claim 11, the battery casing is characterized in that the range of d is 0.3-1.2 mm.
  14. According to claim 1, the battery housing is characterized in that a pressure relief structure is provided on the end wall (11) of the housing (1).
  15. According to claim 14, the battery casing is characterized in that the pressure relief structure includes a weak part (2), and the casing (1) also satisfies the following relationship: 0.004≤m×(b+c)≤0.12, where m is the residual thickness of the weak part (2) in mm.
  16. According to claim 15, the battery casing is characterized in that the range of m is 0.01-0.5 mm.
  17. According to claim 1 or 14, the battery housing is characterized in that an end cap (12) is provided on the other end of the housing (1) relative to the end wall (11), the end cap (12) is fixedly connected to the side wall (13), and the end wall (11) or the end cap (12) is provided with a through hole (3) for setting the pole assembly (5).
  18. According to claim 17, the battery casing is characterized in that the through hole (3) is provided on the end wall (11), and the casing (1) also satisfies the following relationship: 0.005≤k/(b+c)≤0.5, where k is the ratio of the area of the through hole (3) to the area of the end wall (11) where the through hole (3) is located.
  19. According to claim 18, the battery casing is characterized in that the range of k is 0.00125-0.1.
  20. According to claim 1, the battery casing is characterized in that an injection hole (4) is provided on the end wall (11), and the casing (1) also satisfies the following relationship: 0.004≤z/(b+c)≤0.3, where z is the ratio of the area of the injection hole (4) to the area of the end wall (11).

Description

A battery casing, a battery including the casing, and an electrical device thereof. Cross-reference of related applications This application claims priority to Chinese Patent Application No. 202411556207.7, filed on November 4, 2024, entitled "A Battery Housing, a Battery Including the Housing and an Electrical Device Thereof", the entire contents of which are incorporated herein by reference. Technical Field This application relates to the field of battery technology, specifically to a battery casing, a battery including the casing, and an electrical device thereof. Background Technology With the increasing popularity of new energy vehicles, the power battery, as a core component of new energy vehicles, directly determines the vehicle's range, performance, and overall safety. Among these components, the battery casing, as an important part of the power battery, is related to various battery performance aspects such as safety, energy density, and lifespan. Therefore, the battery casing is required to be lightweight while possessing excellent mechanical properties. Deep drawing of metals involves using stamping, ring forming, or metal die-cutting processes to deform sheet metal materials into cylindrical or box-shaped parts. Deep drawing offers high productivity and material utilization, provides dimensional accuracy and low surface roughness, and can manufacture thin-walled and complex parts that are difficult to form using other methods. With increasingly fierce price competition, deep drawing is now widely used for battery casings to reduce raw material and process costs, requiring the casing material to possess excellent tensile ductility. Currently, stainless steel is widely used in products requiring deep drawing due to its high elongation, allowing for the forming of complex shapes with few defects, and its excellent work hardening ability. However, when stainless steel is used for deep drawing, its strength continuously increases due to work hardening, and stress concentration occurs locally, leading to fracture. Summary of the Invention The purpose of this application is to overcome the shortcomings of the prior art in which steel is prone to fracture during deep drawing when used as the material for battery casing, and to provide a battery casing, a battery including the casing, and an electrical device thereof. To achieve the above objectives, in a first aspect of this application, this application provides a battery casing, the casing being made of steel, the steel comprising Ti, Nb and Cr, wherein, based on the total mass of the steel, the mass percentage of Cr is ≥16 wt.%. The housing includes end walls; The shell satisfies the following relationship: 50≤(h/d)/(b+c)≤7000; Where h is the height of the shell, in mm; d represents the thickness of the end wall, in mm; b represents the mass percentage of Ti based on the total mass of the steel, expressed in wt.%. c represents the mass percentage of Nb based on the total mass of steel, expressed in wt.%. As an optional implementation of this application, the shell satisfies the following relationship: 142≤(h/d)/(b+c)≤2000. As an optional implementation of this application, the range of h is 20-300 mm. As an optional embodiment of this application, the range of h is 50-270 mm. As an optional implementation of this application, the range of d is 0.2-1.5 mm. As an optional implementation of this application, the range of d is 0.5-1.0 mm. As an optional embodiment of this application, the range of b+c is 0.2-0.8 wt.%. As an optional embodiment of this application, the range of b+c is 0.25-0.5 wt.%. As an optional embodiment of this application, the range of b is 0.05-0.2 wt.%. As an optional embodiment of this application, the range of c is 0.17-0.5 wt.%. As an optional embodiment of this application, the housing further includes a sidewall, and the housing also satisfies the following relationship: 0.5≤(f/d)/(b+c)≤5, where f is the thickness of the sidewall of the housing in mm. As an optional implementation of this application, the range of f is 0.1-1.2 mm. As an optional embodiment of this application, the range of d is 0.3-1.2 mm. As an optional embodiment of this application, a pressure relief structure is provided on the end wall of one end of the housing. As an optional implementation of this application, the pressure relief structure includes a weak part, and the shell also satisfies the following relationship: 0.004≤m×(b+c)≤0.12, where m is the residual thickness of the weak part in mm. As an optional implementation of this application, the range of m is 0.01-0.5 mm. As an optional embodiment of this application, the housing is provided with an end cap at the other end opposite to the end wall, the end cap is fixedly connected to the side wall, and the end wall or the end cap is provided with a through hole for setting the pole assembly. As an optional implementation of this application, the through hole is provided on the end wall, and the hous