Cylindrical housing, battery and battery pack

Abstract

The utility model relates to new energy battery technical field discloses a kind of cylindrical shell, battery and battery pack, this kind of shell structure strength is high, end wall flatness is good, and the firmness of end wall and other structure of battery is connected is high.The cylindrical shell of the utility model, shell includes titanium element, the mass percentage content of titanium element of shell is greater than or equal to 90%, at least one end wall of shell is provided with convex structure, convex structure is set to protrude towards the inside of shell, other structure area is also set on end wall;In radial direction, the width of single convex structure is W1, unit is mm, the sum of the width of the rest part of convex structure and other structure area except end wall is W2, unit is mm, the height of convex structure along shell axial direction is H, unit is mm, the vickers hardness of shell is a, unit is kgf / mm 2 , the value range of relational expression (W1 / W2)×H / a is 1.8×10 ‑6 ~3×10 ‑3 .

Description

Technical Field

[0001] This utility model relates to the field of new energy battery technology, specifically to a cylindrical shell, a battery, and a battery pack. Background Technology

[0002] Currently, most new energy battery casings are made of metals such as aluminum, aluminum alloy, copper, nickel, stainless steel, and carbon steel. These casings are relatively heavy and cannot meet the lightweight requirements of new energy batteries. To address this, a battery casing containing titanium has emerged in existing technologies to reduce its weight. However, this type of casing has poor flatness, affecting the firmness of the connection between the casing and other structures, and can easily lead to instability when the casing is placed. Utility Model Content

[0003] In view of this, the present invention provides a cylindrical shell, a battery and a battery pack to solve the problems of poor flatness of existing battery shells, affecting the firmness of the connection between the shell and other structures, and poor shell stability.

[0004] In a first aspect, this utility model provides a cylindrical shell for use in a battery. The shell comprises titanium, with a titanium content of 90% or more by mass. The shell includes end walls and side walls. The end walls are located at both ends of the shell along the axial direction. At least one end wall has a protruding structure protruding towards the interior of the shell. Other structural areas are also provided on the end walls. In the radial direction, the width of a single protruding structure is W1 (mm), the sum of the widths of the remaining portions of the end walls excluding the protruding structure and the other structural areas is W2 (mm), the height of the protruding structure along the axial direction of the shell is H (mm), and the Vickers hardness of the shell is a (kgf / mm²). 2 The range of values ​​for the relation (W1 / W2)×H / a is 1.8×10. -6 ~3×10 -3 .

[0005] Beneficial effects: The cylindrical shell of this invention contains titanium, which reduces the weight of the shell and meets the requirements for lightweight battery shells. Furthermore, by providing a protruding structure on at least one end wall of the shell, the structural strength of that end wall can be enhanced. In the radial direction, the width of a single protruding structure is W1, and the sum of the widths of the remaining portion of the end wall excluding the protruding structure and other structural areas is W2. In the axial direction of the shell, the height of the protruding structure is H, and the Vickers hardness of the shell is a. These parameters are correlated to form the relationship (W1 / W2)×H / a, and the value range of the relationship (W1 / W2)×H / a is limited to 1.8×10⁻⁶. -6 ~3×10 -3Within the above-mentioned value range, the structural strength of the end wall of the casing is high, the end wall is not easily deformed by force, significantly improving its flatness. The subsequent connection between the end wall and other battery structures is strong, ensuring the quality of electrical connection. In addition, the end wall of this casing is flat, so it is stable and not easy to shake when placed, with good stability. Moreover, through the above-mentioned limitations, the protruding structure will not occupy too much internal space of the casing and will not affect the setting of other internal structures, so as to ensure that the battery capacity meets the requirements.

[0006] Secondly, the present invention also includes a battery, comprising a battery cell and the aforementioned cylindrical housing, wherein the battery cell is disposed within the housing.

[0007] Since the battery of this utility model includes the cylindrical shell of this utility model and has the same beneficial effects as the cylindrical shell, it will not be described again here.

[0008] Thirdly, the present invention also includes a battery pack, comprising a busbar and a plurality of batteries as described above. The busbar is used to connect adjacent batteries. A terminal post is provided on the end wall of the housing. The busbar includes a housing connection part and a terminal post connection part. The housing connection part connects to the end wall of one of the batteries, and the terminal post connection part connects to the terminal post of another battery.

[0009] Since the battery pack of this utility model includes the battery of this utility model and has the same beneficial effects as the battery, it will not be described again here. Attached Figure Description

[0010] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0011] Figure 1 This is a schematic diagram of the overall cylindrical shell of this utility model;

[0012] Figure 2 This is an overall schematic diagram of the cylindrical shell of this utility model from another perspective;

[0013] Figure 3 for Figure 2 An enlarged schematic diagram of part A in the middle;

[0014] Figure 4 This is a cross-sectional view of the cylindrical shell of this utility model;

[0015] Figure 5 for Figure 4 Enlarged schematic diagram of part B in the middle;

[0016] Figure 6 for Figure 5 An enlarged schematic diagram of section C;

[0017] Figure 7 This is a schematic diagram showing the dimensions of the cylindrical shell end wall protrusion structure in this embodiment.

[0018] Explanation of reference numerals in the attached figures:

[0019] 1. End wall; 2. Side wall; 3. Protruding structure; 4. Pressure relief structure; 5. Injection hole step; 6. Injection hole. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0021] Currently, battery casings are mostly made of metals such as aluminum, aluminum alloy, copper, nickel, stainless steel, and carbon steel. These materials result in heavy casings that cannot meet the lightweight requirements of new energy batteries. While titanium-containing casings can reduce weight, surface processing, such as stamping grooves or through holes, can easily cause significant deformation, leading to poor flatness. This results in poor welding of the casing to other structures, and the poor flatness can cause poor adhesion and welding failure. Furthermore, if the bottom end wall of the casing is too flat, it can cause instability, making the casing prone to shaking and tipping, thus affecting battery performance.

[0022] Based on this, the present invention provides a cylindrical shell with good shell flatness, a battery, and a battery pack.

[0023] The following is combined Figures 1 to 7 This describes embodiments of the cylindrical housing, battery, and battery pack of this utility model.

[0024] According to an embodiment of this utility model, a cylindrical shell is provided for use in a battery. The shell includes titanium, with a titanium content of 90% or more by mass. The shell includes end walls 1 and side walls 2. The end walls 1 are located at both ends of the shell along the axial direction. At least one end wall 1 has a protruding structure 3 protruding towards the interior of the shell. Other structural areas are also provided on the end walls 1. In the radial direction, the width of a single protruding structure 3 is W1 (mm), the sum of the widths of the remaining portions of the end wall 1 excluding the protruding structure 3 and other structural areas is W2 (mm), the height of the protruding structure 3 along the axial direction of the shell is H (mm), and the Vickers hardness of the shell is a (kgf / mm²). 2 The range of values ​​for the relation (W1 / W2)×H / a is 1.8×10. -6 ~3×10 -3 .

[0025] This cylindrical shell contains titanium, which reduces the weight of the shell and meets the requirements for lightweight battery casings. Furthermore, by providing a protruding structure 3 on at least one end wall of the shell, the structural strength of the end wall 1 is enhanced. In the radial direction, the width of a single protruding structure 3 is W1, and the sum of the widths of the remaining portion of the end wall 1 excluding the protruding structure 3 and other structural areas is W2. In the axial direction of the shell, the height of the protruding structure 3 is H, and the Vickers hardness of the shell is a. These parameters are correlated to form the relationship (W1 / W2)×H / a, and the value range of the relationship (W1 / W2)×H / a is limited to 1.8×10⁻⁶. -6 ~3×10 -3 Within the above-mentioned value range, the end wall 1 of the casing has high structural strength and is not easily deformed by force, which significantly improves its flatness. The subsequent connection between the end wall 1 and other battery structures is strong, ensuring connection quality. Furthermore, the end wall 1 of this casing is flat, making it stable and not easy to shake when placed, thus exhibiting good stability. Moreover, through the above-mentioned limitations, the protruding structure 3 will not occupy too much internal space of the casing and will not affect the setting of other internal structures, thereby ensuring that the battery capacity meets the requirements.

[0026] This cylindrical casing, used in cylindrical batteries, serves as a supporting and protective structure. The casing contains internal space where the battery cells and other core components are housed. The casing possesses a certain degree of rigidity to resist external impacts, thereby protecting the battery's core components and ensuring its lifespan.

[0027] In this embodiment, the Vickers hardness of the casing is 'a', and the Vickers hardness 'a' of the casing can be measured by the finished battery product.

[0028] The Vickers hardness α of end wall 1 can be measured using the following method:

[0029] (1) Place the sample stably on the hardness tester table so that the indenter axis is perpendicular to the sample surface.

[0030] (2) Apply the selected test force. The test force should be applied smoothly without impact or vibration. The loading time is generally 2-10s. The time to maintain the test force depends on the material and the magnitude of the test force, usually 10-15s.

[0031] (3) After removing the test force, measure the lengths of the two diagonals of the indentation using a reading microscope, take the arithmetic mean as the diagonal length d of the indentation, and calculate the hardness value. The formula for calculating Vickers hardness a is: a = 0.1891(F) / (d) 2 ), where F is the test force (in N) and d is the diagonal length of the indentation (in mm).

[0032] In this embodiment, the casing is made of a metal material containing titanium. This titanium-containing casing is lightweight, significantly reducing the overall weight of the battery, achieving a lightweight design, and improving battery energy density and range. Furthermore, this titanium-containing casing has high compressive strength, effectively resisting external impacts, compression, and vibration, and more effectively protecting the internal structure of the casing, preventing damage to core battery components due to mechanical stress.

[0033] In this embodiment, the titanium content of the shell is greater than or equal to 90%, for example, the titanium content of the shell is 90%, 92%, 95%, 98%, 99%, etc.

[0034] In this embodiment, the casing is applied to a cylindrical battery, and the positive and negative electrodes of this cylindrical battery are led out on the same side. This cylindrical battery includes a cell, and the cell includes tabs, each tab including a positive tab and a negative tab, which are disposed on the same side of the cell to achieve the same-side lead-out of the battery's positive and negative electrodes. This cylindrical battery with the positive and negative electrodes led out on the same side has a compact structure, small size, and wide applicability.

[0035] The shell includes end walls 1 and side walls 2. End walls 1 are located at both ends of the shell along the axial direction, therefore there are two end walls 1, one located at the top end of the side wall 2 and the other at the bottom end of the side wall 2. The shell can be integrally formed, in which case end walls 1 and side walls 2 are a single structure. Alternatively, the shell can be formed separately, in which case end walls 1 and side walls 2 are manufactured separately, and then end walls 1 and side walls 2 are fixed together by welding to form a complete shell.

[0036] like Figure 1 and Figure 2As shown, in this embodiment, the housing is applied to a cylindrical battery, and the housing is cylindrical in shape. The housing includes an end wall 1 and a side wall 2. The side wall 2 is a cylindrical side wall of the housing, and the end wall 1 is a circular end wall provided at both ends of the side wall 2. During the manufacturing process of the housing, the end wall 1 needs to be formed with other structural areas (such as injection holes, pressure relief grooves, etc.), so the end wall 1 is more prone to deformation than the side wall 2.

[0037] There are two end walls 1, and at least one end wall 1 is provided with a protruding structure 3. For example, the protruding structure 3 can be provided on one of the end walls 1, or the protruding structure 3 can be provided on both end walls 1. The protruding structure 3 can be formed during the manufacturing process of the shell, that is, the protruding structure 3 can be integrally formed with the shell.

[0038] It should be noted that the radial direction is Figure 1 The direction indicated by the middle arrow x is the axial direction of the shell. Figure 1 The direction indicated by the middle arrow y.

[0039] In this embodiment, as Figure 7 As shown, in the radial direction, the number of protruding structures 3 is unlimited, and may be one or more. In the radial direction, the width of a single protruding structure 3 is W1, in mm. The sum of the widths of the remaining parts of the end wall 1 excluding the protruding structures 3 and other structural areas is W2, in mm. In the axial direction of the shell, the height of the protruding structure 3 is H, in mm.

[0040] It should be noted that, in the radial direction, the remaining part of the end wall 1 excluding the protruding structure 3 and other structural areas refers to the part of the end wall 1 excluding the protruding structure 3 and other structural areas such as the injection hole and pressure relief groove in the radial direction.

[0041] In this embodiment, by setting the relationship (W1 / W2)×H / a, the W1 of a single protruding structure 3, the sum of the widths of the end wall 1 excluding the protruding structure 3 and other structural areas, W2, the height H of the protruding structure 3, and the Vickers hardness a of the shell are associated. By controlling the range of values ​​of the above relationship, the flatness of the shell is improved while meeting the requirements for lightweighting. This ensures a high degree of firmness in the connection between the end wall 1 of the shell and other battery structures, guaranteeing the quality of electrical connection. Furthermore, the flatness of the end wall 1 of the shell makes it stable and not easy to shake when placed, resulting in good stability. Moreover, through the above limitations, the protruding structure 3 will not occupy too much internal space of the shell and will not affect the setting of other internal structures of the shell, thus ensuring that the battery capacity meets the requirements.

[0042] If the value of (W1 / W2)×H / a is too small, the overall flatness of the casing will still be poor. When the casing end wall 1 is subsequently connected to other battery structures (such as busbars) (e.g., by welding), the connection strength cannot be guaranteed, increasing the risk of welding failure. Furthermore, when the flatness of the bottom end wall 1 of the casing is very poor, the casing will be unstable when placed and prone to wobbling and tipping. If the value of (W1 / W2)×H / a is too large, it will significantly reduce the size of the internal storage space of the casing, affecting the arrangement of structures such as the battery cells inside the casing, affecting the size of the battery cells, and resulting in low battery capacity that fails to meet performance requirements.

[0043] In this embodiment, the value range of the relation (W1 / W2)×H / a is 1.8×10. -6 ~3×10 -3 Within the aforementioned range, the protruding structure 3 has a moderate size, which can significantly improve the overall flatness of the housing, ensure the firmness of the connection between the subsequent end wall 1 and other battery structures, ensure the quality of electrical connection, and the end wall 1 of the housing is flat, so it is stable and not easy to shake when placed, with good stability. Moreover, the protruding structure 3 does not occupy too much internal space of the housing and does not affect the setting of other internal structures of the housing, so as to ensure that the battery capacity meets the requirements.

[0044] For example, the value of the relation (W1 / W2)×H / a can be 1.8×10. -6 2.5×10 -5 6.4×10 -4 3×10 -3 wait.

[0045] In this embodiment, the protruding structure 3 is continuously arranged along the circumference of the shell, and the protruding structure 3 surrounds the center of the circular end wall 1. The radial cross-sectional shape of the protruding structure 3 can be rectangular, trapezoidal, etc. Figure 3 As shown, the width of the protruding structure 3 in the radial direction is W1, which is the dimension of the protruding structure 3 on the outer surface of the end wall 1. Figure 5 and Figure 7 Taking a perspective example, on the radial section of the shell, the protruding structure 3 has two widths, that is, two width dimensions W1.

[0046] In other embodiments, the protruding structure 3 may also be other structural forms, such as intermittently arranged convex hulls.

[0047] In this embodiment, as Figure 3 , Figure 5As shown, the protruding structure 3 protrudes inward toward the housing to make the external structure of the housing regular and avoid flatness differences on the outer surface of the housing, which is beneficial to the stable installation of the housing. In particular, when the protruding structure 3 is provided on the bottom end wall 1 of the housing, the protruding structure 3 protrudes inward toward the housing, and the bottom end wall 1 of the housing has a regular structure with no obvious flatness differences, which allows the housing to be installed stably, thereby improving the stability of the battery.

[0048] Furthermore, the Vickers hardness α of the shell ranges from 120 kgf / mm². 2 ~600kgf / mm 2 The height H of the protruding structure 3 along the axial direction of the shell ranges from 0.1mm to 1.5mm. The ratio of the width W1 of a single protruding structure 3 to the sum of the widths W2 of the remaining parts of the end wall 1 excluding the protruding structure 3 and other structural areas ranges from 0.01 to 0.3.

[0049] In this embodiment, the Vickers hardness α of the shell ranges from 120 kgf / mm². 2 ~600kgf / mm 2 Within the aforementioned range, the Vickers hardness α of end wall 1 is moderate, which can reduce the degree of deformation of end wall 1 during subsequent stamping processes and improve the flatness of end wall 1. Moreover, it can ensure the structural strength of end wall 101 of the casing, thereby ensuring the overall structural strength of the casing, enabling the casing to effectively support and protect the internal structure of the battery, and ensuring the service life of the battery.

[0050] For example, the Vickers hardness α of the shell can be 120 kgf / mm². 2 260kgf / mm 2 350kgf / mm 2 480kgf / mm 2 560kgf / mm 2 600kgf / mm 2 wait.

[0051] If the height H of the protruding structure 3 is too small, the protruding structure 3 will have limited effect on enhancing the structural strength of the casing. If the height H of the protruding structure 3 is too large, it will occupy too much space inside the casing, affecting the arrangement of structures such as the battery cells inside the casing, and affecting the battery capacity and performance.

[0052] In this embodiment, the height H of the protruding structure 3 ranges from 0.1mm to 1.5mm. Within this range, the height H of the protruding structure 3 is moderate, which can significantly improve the structural strength of the shell, enhance the flatness of the shell, make the shell stable and less prone to shaking or tipping, and at the same time, it will not occupy too much space inside the shell, nor will it affect the arrangement of the battery cells and other structures inside the shell, so that the battery capacity and performance meet the requirements.

[0053] For example, the height H of the protruding structure 3 along the axial direction of the shell can be 0.1mm, 0.5mm, 0.8mm, 1.0mm, 1.3mm, 1.5mm, etc.

[0054] The ratio of the width W1 of a single protruding structure 3 to the sum of the widths W2 of the remaining parts of the end wall 1 excluding the protruding structure 3 and other structural areas is in the range of 0.01 to 0.3. Within the above range, the width of the protruding structure 3 is moderate, does not occupy too much end space, and does not affect the setting of other structural areas and other structures.

[0055] For example, the ratio of the width W1 of a single protruding structure 3 to the sum of the widths W2 of the remaining parts of the end wall 1 excluding the protruding structure 3 and other structural areas can be 0.01, 0.05, 0.1, 0.2, 0.3, etc.

[0056] Furthermore, in the radial direction, the protruding structure 3 is spaced apart from the sidewall 2.

[0057] like Figure 7 As shown, in the radial direction, the protruding structure 3 and the side wall 2 are spaced apart, and there is a certain distance between them, so that the protruding structure 3 is not located at the edge of the shell end wall 1. When forming the protruding structure 3, it is not easy to cause damage to the shell edge, and at the same time, both the protruding structure 3 and the shell edge are easier to form.

[0058] Furthermore, the distance d1 between the protruding structure 3 and the sidewall 2 ranges from 7mm to 29mm.

[0059] like Figure 7 As shown, the protruding structure 3 is spaced apart from the side wall 2. If the distance d1 between the protruding structure 3 and the side wall 2 is too small, the protruding structure 3 will be too close to the edge of the shell, which will easily cause deformation of the shell edge during the molding of the protruding structure 3, increasing the processing difficulty. If the distance d1 between the protruding structure 3 and the side wall 2 is too large, the protruding structure 3 will be relatively centered on the end wall 1, affecting the setting of other structures on the end wall 1 and reducing the space utilization rate.

[0060] In this embodiment, the radial distance d1 between the protruding structure 3 and the sidewall 2 ranges from 7mm to 29mm. Within this range, the distance d1 between the protruding structure 3 and the sidewall 2 is neither too small nor too large, and the protruding structure 3 is not too close to the edge of the shell. When forming the protruding structure 3, it is not easy to cause deformation of the shell edge, which reduces the processing difficulty. Moreover, the position of the protruding structure 3 will not affect the setting of other structures on the endwall 1, thus improving the space utilization rate.

[0061] For example, the distance d1 between the protruding structure 3 and the sidewall 2 can be 7mm, 12mm, 16mm, 21mm, 26mm, 29mm, etc.

[0062] Furthermore, the other structural areas are pressure relief structures 4, with protruding structures 3 and pressure relief structures 4 arranged alternately.

[0063] like Figure 3 As shown, in this embodiment, the protruding structure 3 is disposed on the bottom end wall 1 of the housing. The other structural area disposed on the bottom end wall 1 is a pressure relief structure 4, which is a battery explosion-proof valve. The battery explosion-proof valve is a core structure for ensuring battery safety, and its function is to cope with the surge in internal pressure under abnormal conditions such as battery thermal runaway. When a large amount of gas is generated inside the battery due to thermal runaway (such as short circuit, overcharge, etc.), causing a sudden increase in pressure, the explosion-proof valve automatically opens to relieve pressure, preventing the battery housing from exploding due to overpressure.

[0064] In this embodiment, the protruding structure 3 and the pressure relief structure 4 are spaced apart so that the protruding structure 3 and the pressure relief structure 4 do not affect each other, which can strengthen the shell structure strength, ensure the shell flatness, and at the same time ensure the normal operation of the pressure relief structure 4.

[0065] Furthermore, in the radial direction, the interval d2 between the protruding structure 3 and the pressure relief structure 4 ranges from 1 mm to 6 mm.

[0066] The protruding structure 3 and the pressure-relieving structure 4 are spaced apart. If the distance d2 between the protruding structure 3 and the pressure-relieving structure 4 is too small, the protruding structure 3 will strengthen the structural strength of the end wall 1 after molding. If the distance between the protruding structure 3 and the pressure-relieving structure 4 is too close, the force-bearing area between them will be small, and deformation will easily occur when the pressure-relieving structure 4 is stamped. If the distance d2 between the protruding structure 3 and the pressure-relieving structure 4 is too large, the effect of the protruding structure 3 in strengthening the structural position of the pressure-relieving structure 4 will be poor, and it will not effectively prevent the deformation of the end wall 1 caused by the pressure-relieving structure 4.

[0067] like Figure 7 As shown, in this embodiment, the distance d2 between the protruding structure 3 and the pressure relief structure 4 ranges from 1 mm to 6 mm. Within this range, the distance d2 between the protruding structure 3 and the pressure relief structure 4 is moderate, the stress-bearing area between the protruding structure 3 and the pressure relief structure 4 is moderate, and deformation is not easily caused. Moreover, the protruding structure 3 has a good reinforcing effect on the area near the pressure relief structure 4, preventing deformation of the end wall 1 caused by the pressure relief structure 4.

[0068] For example, the distance d2 between the protruding structure 3 and the pressure relief structure 4 can be 1mm, 2mm, 3mm, 5mm, 6mm, etc.

[0069] Furthermore, the pressure relief structure 4 is a groove, and the residual thickness t of the end wall 1 after the groove is formed ranges from 0.04mm to 0.1mm. The value range of the relationship (W1 / W2)×H / a is 2.0×10. -6 ~2×10-3 .

[0070] like Figure 3 As shown, the pressure relief structure 4 is a groove, which is usually stamped into the end wall 1. The groove is formed by recessing from the outer surface of the end wall 1 inward, and the thickness of the groove is reduced, thereby forming a weak area, which is the pressure relief structure 4. In this embodiment, the pressure relief structure 4 is arranged around the center of the end wall 1, forming an annular groove structure.

[0071] like Figure 6 As shown, after the groove is formed in the end wall 1, the residual thickness t of the end wall 1 is in the range of 0.04mm to 0.1mm. Within the above range, the residual thickness t of the end wall 1 will not be too large or too small. When abnormal situations such as thermal runaway occur inside the battery casing, the pressure relief structure 4 can automatically open to relieve pressure, prevent the casing from exploding, and improve the safety of battery use.

[0072] For example, the residual thickness t after the end wall 1 is formed into a groove can be 0.04mm, 0.05mm, 0.07mm, 0.09mm, 0.1mm, etc.

[0073] To ensure the proper functioning of the pressure relief structure 4 and guarantee battery safety, the residual thickness t of the end wall 1 after forming the groove will be relatively small compared to the thickness of the end wall 1. Therefore, it is necessary to further strengthen the structural strength of the casing, i.e., strengthen the structural strength of the end wall 1. This narrows the range of the relationship (W1 / W2)×H / a to 1.8×10⁻⁶. -6 ~2×10 -3 This is to increase the strength of the shell structure, prevent severe deformation of the shell during the molding of the pressure relief structure 4, and improve the flatness of the shell.

[0074] At this point, the value of the relation (W1 / W2)×H / a can be 2.0×10. -6 5.7×10 -5 8.4×10 -4 2×10 -3 wait.

[0075] Furthermore, the other structural area is the injection hole step 5, the height h of the injection hole step 5 ranges from 0.2mm to 0.8mm, and the value of the relationship (W1 / W2)×H / a ranges from 1.9×10 -6 ~2×10 -3 .

[0076] like Figures 2-3As shown, in this embodiment, the protruding structure 3 is provided on the bottom end wall 1 of the housing. A liquid injection hole step 5 is also provided on the bottom end wall 1. A liquid injection hole 6 is provided in the liquid injection hole step 5. The liquid injection hole 6 is a through hole. The liquid injection hole 6 is the inlet for injecting electrolyte into the battery. After the electrolyte is injected through the liquid injection hole 6, the liquid injection hole 6 is sealed by a sealing member. The sealing member is provided in the liquid injection hole step 5 to prevent electrolyte leakage inside the battery.

[0077] The height h of the injection hole step 5 is in the range of 0.2mm to 0.8mm. Since a sealing element for sealing the injection hole 6 needs to be installed inside the injection hole step 5, and the sealing element has a certain thickness, in order to accommodate the insulating element and ensure its stable position, the height h of the injection hole step 5 should match the thickness of the insulating element. Optionally, after the insulating element is installed into the injection hole step 5, the bottom of the insulating element and the injection hole step 5 are flush.

[0078] Therefore, the height h of the injection hole step 5 should meet the above range. For example, the height h of the injection hole step 5 can be 0.2mm, 0.4mm, 0.5mm, 0.7mm, 0.8mm, etc.

[0079] To ensure reliable sealing, the height h of the injection hole step 5 cannot be too small. Therefore, it is necessary to further strengthen the structural strength of the shell, specifically the end wall 1. This narrows the range of the relationship (W1 / W2)×H / a to 1.8×10⁻⁶. -6 ~2×10 -3 This is to increase the structural strength of the shell, prevent severe deformation of the shell when forming the injection hole step 5, and improve the flatness of the shell.

[0080] At this point, the value of the relation (W1 / W2)×H / a can be 1.9×10. -6 4.9×10 -5 8.6×10 -4 02×10 -3 wait.

[0081] Furthermore, in the radial direction, the protruding structure 3 is spaced apart from the injection hole step 5.

[0082] In this embodiment, the protruding structure 3 and the injection hole step 5 are spaced apart so that the protruding structure 3 and the injection hole step 5 do not affect each other, which can strengthen the shell structure, ensure the shell flatness, and at the same time ensure that a sealing element can be reliably installed in the injection hole step 5 to ensure the sealing effect of the injection hole 6.

[0083] In this embodiment, the protruding structure 3 is provided on the bottom end wall 1 of the housing, and the end wall 1 is also provided with a pressure relief structure 4 and a liquid injection hole step 5.

[0084] by Figure 7 For example, the sum of the widths of the remaining parts of the end wall 1 excluding the protruding structure 3 and other structural areas is W2. This means that in the radial direction, the overall width of the end wall 1 is W3, the width of a single protruding structure 3 is W1, there are two width dimensions of the protruding structure 3, and there are three other structural areas: two pressure relief structures 4 and one injection hole step 5. The width of the pressure relief structure 4 is W6, the width of the injection hole step 5 is W5, and the sum of the widths of the other structural areas is W4 (W4 = W5 + W6 + W6). Therefore, the sum of the widths of the remaining parts of the end wall 1 excluding all the protruding structures 3 and other structural areas is W2 = W3 - W1 - W1 - W4.

[0085] Furthermore, the distance d3 between the protruding structure 3 and the injection hole step 5 ranges from 22mm to 26mm.

[0086] The protruding structure 3 and the injection hole step 5 are spaced apart. If the distance d3 between the protruding structure 3 and the injection hole step 5 is too small, the force-bearing area between them is small, and deformation is likely to occur when the injection hole volume 5 is pressed. If the distance d2 between the protruding structure 3 and the injection hole step 5 is too large, the reinforcement effect of the protruding structure 3 on the injection hole step 5 is poor, and it cannot effectively prevent the deformation of the end wall 1 caused by the injection hole step 5.

[0087] like Figure 7 As shown, in this embodiment, the distance d3 between the protruding structure 3 and the injection hole step 5 ranges from 22mm to 26mm. Within this range, the distance d2 between the protruding structure 3 and the injection hole step 5 is neither too large nor too small. The area between the protruding structure 3 and the injection hole step 5 forms a reinforcing structure, reducing the risk of shell deformation and affecting shell flatness when the injection hole step 5 is installed. At the same time, it does not affect the installation of other structures on the end wall 1, ensuring the utilization rate of shell space.

[0088] For example, the distance d3 between the protruding structure 3 and the injection hole step 5 can be 22mm, 23mm, 24mm, 25mm, or 26mm.

[0089] Furthermore, in the radial direction, the width W1 of a single protruding structure 3 ranges from 2 mm to 4 mm.

[0090] To improve the strength of the shell structure and enhance the flatness of the shell, the width W1 of the protruding structure 3 is in the range of 2mm to 4mm.

[0091] If the width W1 of the protruding structure 3 is too small, the protruding structure 3 will be difficult to set up and will have a limited effect on enhancing the strength of the shell structure. If the width W1 of the protruding structure 3 is too large, it will affect the setting of other structures on the end wall 1 and affect the space utilization.

[0092] In this embodiment, the width W1 of the protruding structure 3 is in the range of 2mm to 4mm. Within the above range, the width W1 of the protruding structure 3 is moderate, neither too large nor too small, which can significantly improve the structural strength of the shell, enhance the flatness of the shell, and ensure a high degree of firmness in the connection between the end wall and other battery structures. The shell is placed stably and is not easy to shake or tip over, while not affecting the setting of other structures on the end wall 1.

[0093] For example, the width W1 of the protruding structure 3 can be 2mm, 2.5mm, 3mm, 3.7mm, 4mm, etc.

[0094] This embodiment also provides a battery, including a battery cell and the aforementioned cylindrical casing, with the battery cell disposed inside the casing.

[0095] The battery cell includes a battery cell body and a tab. The tab extends from the end of the battery cell body and is electrically connected to one end wall 1 of the housing. The end wall 1 of the electrically connected tab is provided with a protruding structure 3.

[0096] A battery cell is the energy storage unit of a battery, storing and releasing electrical energy through electrochemical reactions within the cell (the interaction of the positive electrode material, negative electrode material, and electrolyte). A battery cell consists of a positive electrode sheet, a negative electrode sheet, and a separator between them, formed by winding or stacking. The positive electrode sheet includes a positive current collector and a positive active material. The positive current collector can be made of metals such as aluminum foil, nickel foil, or stainless steel, or it can be a composite foil formed by combining metals and insulating materials. The positive active material includes the main positive active material, conductive agent, and binder. The main positive active material includes one or more lithium-containing positive active materials such as lithium iron phosphate, ternary materials containing nickel, cobalt, and manganese, and lithium manganese iron phosphate. Similarly, the negative electrode sheet includes a negative current collector and a negative active material. The negative current collector can be made of metals such as copper foil, aluminum foil, or stainless steel, or it can be a composite foil formed by combining metals and insulating materials. The negative electrode active material includes the negative electrode active material, conductive agent, binder, etc. The negative electrode active material includes one or more of the following: artificial graphite, natural graphite, silicon carbide, silicon oxide, lithium titanate, etc.

[0097] A battery cell consists of a cell body and tabs. The tabs are led out from the end of the cell body and are electrically connected to the cell body. The tabs are the current output terminals of the cell, that is, the tabs serve as conductive electrodes connecting the cell body to the external circuit to transmit current.

[0098] The electrode tab is electrically connected to one end wall 1 of the housing by welding. The end wall 1 of the electrode tab is provided with a protruding structure 3. In this embodiment, the top end wall 1 of the housing is electrically connected to the electrode tab. The top end wall 1 is provided with a protruding structure 3 to enhance the structural strength of the top end wall 1 of the housing, improve the flatness of the top end wall 1, thereby ensuring the connection between the electrode tab and the housing and avoiding welding failures.

[0099] In this embodiment, the battery is a cylindrical battery, with the positive and negative terminals leading out on the same side. This cylindrical battery also includes terminals and current collectors. The battery cell includes tabs, specifically a positive tab and a negative tab, both located on the same side of the cell to ensure that the positive and negative terminals are led out on the same side. This type of cylindrical battery with both positive and negative terminals on the same side has a compact structure, small size, and wide applicability. The current collector is electrically connected to the tabs and terminals to facilitate the transmission of current within the battery. Of course, the battery in this embodiment also has other structures common to existing batteries, which will not be elaborated upon here.

[0100] This battery, using the casing of this embodiment, can improve the structural strength and flatness of the casing while meeting the requirements for lightweight casing. This results in a high degree of firmness in the connection between the end wall and other battery structures, ensuring the quality of electrical connection. Furthermore, the flat end wall of this casing makes it stable and not easy to shake when placed, providing good stability. Moreover, the protruding structure 3 does not occupy too much internal space of the casing and does not affect the setting of other internal structures, thus ensuring that the battery capacity meets the requirements.

[0101] In other embodiments, the electrode is led out from the end of the cell body and electrically connected to one end wall 1 of the housing. The other end wall 1 of the housing is provided with a protruding structure 3 to optimize the installation space, avoid structural interference, and make full use of the installation space.

[0102] Furthermore, in the axial direction of the shell, the height H of the protruding structure 3 ranges from 0.1 mm to 1 mm.

[0103] In this embodiment, since the tab is electrically connected to the top end wall 1, sufficient space needs to be reserved. At this time, the range of the height H of the protruding structure 3 is narrowed. The range of the height H of the protruding structure 3 is 0.1mm to 1mm, so as to avoid the height H of the protruding structure 3 being too large and affecting the electrical connection between the tab and the top end wall 1.

[0104] For example, the height H of the protruding structure 3 can be 0.1mm, 0.3mm, 0.5mm, 0.7mm, 1mm, etc.

[0105] This embodiment also provides a battery pack, including a busbar and a plurality of batteries as described above. The busbar is used to connect adjacent batteries. A terminal post is provided on the end wall 1 of the housing. The busbar includes a housing connection part and a terminal post connection part. The housing connection part is connected to the end wall 1 of one of the batteries, and the terminal post connection part is connected to the terminal post of another battery.

[0106] The battery pack includes multiple batteries according to this embodiment. Each battery is a single cell, and the number of batteries is selected according to the power demand of the battery. For example, the battery pack may include two, three, four, or five single cells, etc. The individual cells are electrically connected to form the battery pack.

[0107] Busbars are used to connect adjacent batteries. They can collect the current from each individual battery cell to form a unified current output, thereby improving battery system efficiency and optimizing the internal space layout of the batteries. Busbars can be made of materials such as copper, aluminum, iron, stainless steel, aluminum alloy, and nickel.

[0108] A terminal post is provided on the end wall 1 of the casing. The busbar includes a casing connection part and a terminal post connection part. The casing connection part connects to the end wall 1 of one battery, and the terminal post connection part connects to the terminal post of another battery, thereby realizing the electrical connection between adjacent batteries. All of the above electrical connection methods are welding.

[0109] Of course, this battery pack also has other structures that are present in existing battery packs, which will not be elaborated here.

[0110] Furthermore, the housing connection part is electrically connected to one of the end walls 1 of the housing, and the end wall 1 of the electrically connected housing connection part is provided with a protruding structure 3.

[0111] The busbar housing connection is electrically connected to one of the end walls 1 of the housing. To enhance the structural strength of the end wall 1 and improve its flatness, and to ensure the connection between the housing connection and the end wall 1, a protruding structure 3 is provided on the end wall 1 to enhance its structural strength, improve its flatness, and avoid welding failures.

[0112] Furthermore, there is a welding area between the end wall 1 and the shell connection, and the welding area is spaced apart from the protruding structure 3.

[0113] There is a welding area between the end wall 1 and the housing connection of the busbar. The protruding structure 3 is spaced apart from the welding area. The position of the protruding structure 3 avoids the welding area so as to avoid the protruding structure 3 affecting the electrical connection between the end wall 1 and the housing connection and to ensure the welding quality of the end wall 1 and the housing connection.

[0114] Although embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A cylindrical shell, characterized in that, For use in batteries, the housing includes titanium, the titanium content of the housing is greater than or equal to 90% by mass, the housing includes an end wall (1) and a side wall (2), the end wall (1) is disposed at both ends of the housing in the axial direction, at least one end wall (1) is provided with a protruding structure (3), the protruding structure (3) is provided to protrude toward the interior of the housing, and other structural areas are also provided on the end wall (1); In the radial direction, the width of a single protruding structure (3) is W1 in mm, the sum of the widths of the end wall (1) excluding the protruding structure (3) and the other structural areas is W2 in mm, the height of the protruding structure (3) along the axial direction of the shell is H in mm, and the Vickers hardness of the shell is a in kgf / mm. 2 The range of values ​​for the relation (W1 / W2)×H / a is 1.8×10. -6 ~3×10 -3 .

2. The cylindrical shell according to claim 1, characterized in that, The Vickers hardness α of the shell is in the range of 120 kgf / mm². 2 ~600kgf / mm 2 The height H of the protruding structure (3) along the axial direction of the shell ranges from 0.1mm to 1.5mm, and the ratio of the width W1 of a single protruding structure (3) to the sum of the widths W2 of the remaining parts of the end wall (1) excluding the protruding structure (3) and the other structural areas ranges from 0.01 to 0.

3.

3. The cylindrical shell according to claim 1, characterized in that, In the radial direction, the protruding structure (3) is spaced apart from the sidewall (2).

4. The cylindrical shell according to claim 3, characterized in that, In the radial direction, the distance d1 between the protruding structure (3) and the sidewall (2) ranges from 7 mm to 29 mm.

5. The cylindrical shell according to claim 1, characterized in that, The other structural areas are pressure relief structures (4), and the protruding structures (3) and the pressure relief structures (4) are spaced apart.

6. The cylindrical shell according to claim 5, characterized in that, In the radial direction, the distance d2 between the protruding structure (3) and the pressure relief structure (4) ranges from 1 mm to 6 mm.

7. The cylindrical shell according to claim 5, characterized in that, The pressure relief structure (4) is a groove, and the residual thickness t of the end wall (1) after forming the groove ranges from 0.04 mm to 0.1 mm. The value range of the relationship (W1 / W2)×H / a is 2.0×10. -6 ~2×10 -3 .

8. The cylindrical shell according to claim 1, characterized in that, The other structural area is the injection hole step (5), the height h of which ranges from 0.2 mm to 0.8 mm, and the relationship (W1 / W2)×H / a ranges from 1.9×10. -6 ~2×10 -3 .

9. The cylindrical shell according to claim 8, characterized in that, In the radial direction, the protruding structure (3) is spaced apart from the injection hole step (5).

10. The cylindrical shell according to claim 9, characterized in that, In the radial direction, the distance d3 between the protruding structure (3) and the injection hole step (5) ranges from 22mm to 26mm.

11. The cylindrical shell according to any one of claims 1-9, characterized in that, In the radial direction, the width W1 of a single protruding structure (3) ranges from 2 mm to 4 mm.

12. A battery, characterized in that, It includes a battery cell and a cylindrical housing as described in any one of claims 1-11, wherein the battery cell is disposed within the housing.

13. The battery according to claim 12, characterized in that, The battery cell includes a battery cell body and a tab. The tab extends from the end of the battery cell body and is electrically connected to one end wall (1) of the housing. The end wall (1) electrically connected to the tab is provided with a protruding structure (3).

14. The battery according to claim 12, characterized in that, The battery cell includes a battery cell body and a tab. The tab extends from the end of the battery cell body and is electrically connected to one end wall (1) of the housing. The other end wall (1) of the housing is provided with a protruding structure (3).

15. The battery according to claim 13, characterized in that, In the axial direction of the housing, the height H of the protruding structure (3) ranges from 0.1 mm to 1 mm.

16. A battery pack, characterized in that, The device includes a busbar and a plurality of batteries as described in any one of claims 12-15, the busbar being used to connect adjacent batteries, and a terminal post being provided on the end wall (1) of the housing, the busbar including a housing connection portion and a terminal post connection portion, the housing connection portion connecting to the end wall (1) of one of the batteries, and the terminal post connection portion connecting to the terminal post of another battery.

17. The battery pack according to claim 16, characterized in that, The housing connection portion is electrically connected to one of the end walls (1) of the housing, and the end wall (1) electrically connected to the housing connection portion is provided with a protruding structure (3).

18. The battery pack according to claim 17, characterized in that, There is a welding area between the end wall (1) and the housing connection portion, and the welding area is spaced apart from the protruding structure (3).

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