Design method of lower box body, lower box body and power battery

Abstract

The invention discloses a lower box body design method, a lower box body and a power battery. The lower box body is used for a power battery and comprises a lower box body assembly and a force guiding anti-collision beam, and the force guiding anti-collision beam is arranged in front of the lower box body assembly; when collision occurs, collision energy is firstly transmitted to the force guiding anti-collision beam, and the force guiding anti-collision beam transmits and distributes the collision energy to the lower box body assembly and the automobile body in sequence. According to the technical scheme, the force guiding anti-collision beam is designed on the front portion of the power battery, collision energy is distributed and transmitted, the collision energy is transmitted to a vehicle body through a plurality of force transmission paths, and a battery cell of the power battery is prevented from being damaged; according to the technical scheme provided by the invention, a two-stage energy absorption buffer area is arranged between the force guiding anti-collision beam and the power battery and at the front part of the power battery to absorb the collision energy of the whole vehicle and protect the battery cell of the power battery; the anti-collision force guiding beam for the front portion of the power battery provides multi-scene and multi-working-condition daily protection for the power battery, such as bottom scraping working condition protection for the power battery, square brick and well lid and power battery front portion collision protection and the like.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of new energy vehicle power battery protection technology, in particular to a lower box design method, a lower box and a power battery. BACKGROUND

[0002] With the upgrading of automobile consumption and the improvement of energy saving and environmental protection requirements, electric vehicles are greatly supported by national policy, and automobile manufacturers continue to increase research and development efforts. However, the power battery of the electric vehicle is prone to thermal runaway in a collision accident due to its special structure, which may further cause fire and explosion, thereby seriously endangering the safety of the driver and passengers. Therefore, the collision protection of the power battery is crucial.

[0003] The existing power battery collision protection scheme only considers designing an energy absorption structure to achieve protection through energy absorption and collapse during collision, but the protection effect is not ideal.

[0004] Therefore, there is an urgent need for a power battery lower box structure and design method that takes into account collision energy conduction and absorption and meets the protection requirements of multiple scenarios to address the shortcomings of existing technology. SUMMARY

[0005] The purpose of the present application is to solve the technical problem of the insufficient protection of the existing lower box of the electric vehicle to the power battery in the prior art, and to provide a lower box design method, a lower box and a power battery, so that when the electric vehicle collides, the collision energy is transmitted to the vehicle body while absorbing energy to meet the protection requirements of the power battery during daily use.

[0006] To achieve the purpose of the present application, the technical solutions provided by the present application are as follows:

[0007] First aspect

[0008] The present application provides a lower box for a power battery, comprising a lower box assembly and a force guiding crash beam, the force guiding crash beam is arranged in front of the lower box assembly; when a collision occurs, the collision energy is first transmitted to the force guiding crash beam, and the force guiding crash beam conducts and distributes the collision energy to the lower box assembly and the vehicle body in turn.

[0009] Further, the force guiding crash beam is designed with a guide structure, and the height direction of the force guiding crash beam is lower than the lowest point of the power battery; when the power battery is scraped or collides with the front part of the power battery, the collision is guided to the bottom guard plate of the power battery.

[0010] Further, the guide angle of the guide structure is in the range of 90°-150°.

[0011] Furthermore, the lower housing assembly includes a right side frame assembly, a front frame assembly, a left frame assembly, and a rear frame assembly connected in a square shape; the force-guiding anti-collision beam is connected to the right side frame assembly and the left frame assembly, and a first energy-absorbing zone is designed between it and the front frame assembly, and a second energy-absorbing zone is designed inside the front frame assembly, forming a two-level energy-absorbing buffer for collision energy.

[0012] Furthermore, the first and second energy-absorbing zones are filled with cushioning material.

[0013] Furthermore, the front frame assembly weakens the strength of the second energy absorption zone, thus allowing it to collapse and absorb energy upon impact. At the same time, a high-strength cutoff structure is designed to interrupt the collapse deformation, forming protection for the inside of the power battery.

[0014] Furthermore, the lower housing assembly also includes a front fixing point, a crossbeam, a middle fixing point, a rear fixing point, and a longitudinal beam; the force-guiding anti-collision beam is also connected to the front fixing point; the front fixing point, the middle fixing point, and the rear fixing point are connected to the vehicle body, and the longitudinal beam, the front fixing point, the middle fixing point, and the rear fixing point are arranged on the same axis in the left-right direction; the left frame assembly and the right frame assembly are symmetrical structures; the right frame assembly includes a frame, a frame fixing beam, and a connecting bushing; the right frame is connected to the vehicle body through the frame fixing beam and the connecting bushing; the frame fixing beam is connected to the force-guiding anti-collision beam, and the length of the frame fixing beam is greater than that of the frame.

[0015] Furthermore, when a collision occurs, the collision energy is first transferred to the force-guiding anti-collision beam, which then conducts and distributes the collision energy to the left and right side frame assemblies and the longitudinal beam force transmission path. The force transmission paths of the left and right side frame assemblies include symmetrically arranged left side frame assembly force transmission paths and right side frame assembly force transmission paths. In the right side frame assembly force transmission path, the collision energy is conducted to the vehicle body through the frame fixing beam and multiple connecting bushings. The longitudinal beam force transmission path involves the collision energy being conducted to the vehicle body sequentially through the front fixing point, the longitudinal beam, the middle fixing point, and the rear fixing point.

[0016] Second aspect

[0017] This invention provides a lower housing design method for realizing the lower housing, comprising the following steps:

[0018] Step S1: Design the guiding angle of the guiding beam. The guiding angle ranges from 30° to 75° and is used to transfer collision energy to the force transmission path.

[0019] Step S2: Design the cross-sectional structure of the force-guided anti-collision beam. The cross-sectional and longitudinal dimensions are determined based on the power battery layout space and protection requirements. The height of the force-guided anti-collision beam is lower than the lowest point of the power battery. The wall thickness of the force-guided anti-collision beam ranges from 1.0mm to 4mm.

[0020] Step S3: Design the guiding structure of the force-guided anti-collision beam. The guiding angle ranges from 90° to 150°. When the power battery scrapes the bottom or the front of the power battery collides, the collision will be guided to the bottom protection plate of the power battery.

[0021] Step S4: Connect the force-guiding anti-collision beam to the frame fixing beam and the front fixing point. The length of the frame fixing beam is greater than the frame, and the length of the frame fixing beam extending beyond the frame is 1mm-20mm.

[0022] Step S5: Design the collision force transmission path, including the force transmission paths of the left and right frame assemblies and the longitudinal beam force transmission path; the force transmission paths of the left and right frame assemblies include the symmetrically arranged force transmission paths of the left frame assembly and the right frame assembly, wherein the force transmission path of the right frame assembly is: force guiding anti-collision beam → frame fixing beam → connecting bushing → vehicle body; the force transmission path of the longitudinal beam is: force guiding anti-collision beam → front fixing point → longitudinal beam → middle fixing point, rear fixing point → vehicle body;

[0023] Step S6: Design the first energy-absorbing zone and the second energy-absorbing zone. The width of the first energy-absorbing zone is 50mm-120mm, and the width of the second energy-absorbing zone is 30mm-200mm. Filling buffer material is placed in the first energy-absorbing zone and the second energy-absorbing zone.

[0024] Step S7: The front frame assembly weakens the strength of the second energy absorption zone, so that it can collapse and absorb energy during a collision. At the same time, a high-strength cutoff structure is designed to cut off the collapse deformation and form protection for the inside of the power battery.

[0025] Third aspect

[0026] The present invention provides a power battery, including battery cells and a lower housing, wherein the battery cells are installed in the lower housing.

[0027] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0028] (1) The technical solution provided in this application designs a force-guiding anti-collision beam at the front of the power battery to distribute and conduct collision energy, and transmit the collision energy to the vehicle body through multiple force transmission paths to avoid damage to the power battery cells;

[0029] (2) The technical solution provided in this application absorbs the collision energy of the whole vehicle and protects the power battery cells in the two-level energy-absorbing buffer area at the front of the power battery between the force-guided anti-collision beam and the power battery.

[0030] (3) The front anti-collision guide beam of the power battery provided in this application provides daily protection for the power battery in multiple scenarios and working conditions, such as protection against scraping of the power battery bottom, and protection against collisions between bricks, manhole covers and the front of the power battery.

[0031] (4) The technical solution provided in this application has a simple structure and strong adaptability, and is fully compatible with power batteries with all materials of housing and all types of cells. Attached Figure Description

[0032] Figure 1 This is a top view of the lower housing structure provided in an embodiment of this application;

[0033] Figure 2 for Figure 1 Schematic diagram of cross section along the AA direction;

[0034] Figure 3 for Figure 1 Schematic diagram of the enlarged section;

[0035] Figure 4 for Figure 1 Schematic diagram of the cross section along the BB direction;

[0036] Figure 5 This is a schematic diagram of the collision force transmission path in the embodiments of this application;

[0037] In the diagram, the components are: lower box assembly 1, force-guiding anti-collision beam 2, right side frame assembly 11, front frame assembly 12, front fixing point 13, left frame assembly 14, crossbeam 15, middle fixing point 16, rear fixing point 18, longitudinal beam 19, rear frame 17, first energy-absorbing zone a, second energy-absorbing zone b, frame 111, frame fixing beam 112, connecting bushing 113, force-guiding angle n, enlarged part I, cross-sectional dimension w, longitudinal cross-sectional dimension l, wall thickness t, guide angle d, length h, high-strength cutoff structure 20, force transmission path of left frame assembly 21, and force transmission path of right frame assembly 22. Detailed Implementation

[0038] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0039] Example 1

[0040] like Figures 1-4 As shown, this embodiment provides a lower housing for a power battery, including a lower housing assembly 1 and a force-guiding anti-collision beam 2. The force-guiding anti-collision beam 2 is arranged in front of the lower housing assembly 1. In the event of a collision, the collision energy is first transferred to the force-guiding anti-collision beam 2, and the force-guiding anti-collision beam 2 conducts and distributes the collision energy to the lower housing assembly 1 and the vehicle body in sequence.

[0041] It should be noted that the lower housing 1 includes, but is not limited to, processes and materials such as aluminum alloy profile welding and roll-formed steel welding. The force-guiding anti-collision beam 2 includes, but is not limited to, processes and materials such as aluminum alloy profiles, roll-formed steel, and steel pipes.

[0042] It should be noted that, Figure 1 The left side is the front of the vehicle. The technical solution provided in this application designs a force-guiding anti-collision beam at the front of the power battery to distribute and conduct collision energy, transferring the collision energy to the vehicle body through multiple force transmission paths to avoid damage to the power battery cells.

[0043] Furthermore, the force-guiding anti-collision beam 2 is designed with a guiding structure, and its height is lower than the lowest point of the power battery. When the power battery scrapes against the bottom or collides with the front of the power battery, the impact is guided to the bottom protective plate of the power battery, preventing damage to the front and potential failures in airtightness, insulation, etc. The guiding structure of the force-guiding anti-collision beam 2 is not limited to... Figure 4 The cross-sectional view shown includes all structural forms with guiding functions. Preferably, the guiding angle d of the guiding structure is in the range of 90°-150°.

[0044] Preferably, the lower housing assembly 1 includes a right side frame assembly 11, a front frame assembly 12, a left frame assembly 14, and a rear frame assembly 17 connected in a square shape; the force-guiding anti-collision beam 2 is connected to the right side frame assembly 11 and the left frame assembly 14, and a first energy-absorbing zone a is designed between it and the front frame assembly 12, while a second energy-absorbing zone b is designed inside the front frame assembly 12, forming a two-stage energy absorption buffer for collision energy. The first energy-absorbing zone a and the second energy-absorbing zone b are filled with cushioning material to enhance the energy absorption effect. Preferably, the front frame assembly 12 weakens the strength of the second energy-absorbing zone b, so that it can collapse and absorb energy during a collision, and at the same time, a high-strength cutoff structure 20 is designed to cut off the collapse deformation, forming internal protection for the power battery and protecting the internal cells of the power battery from damage.

[0045] The lower housing assembly 1 also includes a front fixing point 13, a crossbeam 15, a middle fixing point 16, a rear fixing point 18, and a longitudinal beam 19; the force-guiding anti-collision beam 2 is also connected to the front fixing point 13; the front fixing point 13, the middle fixing point 16, and the rear fixing point 18 are bolted to the vehicle body; the longitudinal beam 19, the front fixing point 13, the middle fixing point 16, and the rear fixing point 18 are arranged on the same axis in the left-right direction (Y-direction of the whole vehicle); the left frame assembly 14 and the right frame assembly 11 are paired. The structure is described as follows: The right side frame assembly 11 includes a frame 111, a frame fixing beam 112, and a connecting bushing 113; the right side frame is bolted to the vehicle body through the frame fixing beam 112 and the connecting bushing 113; the frame fixing beam 112 is connected to the force-guiding anti-collision beam 2, and the length of the frame fixing beam 112 is greater than that of the frame 111, so as to ensure that the collision energy is conducted to the vehicle body through the frame fixing beam 112 and the connecting bushing 113 without damaging the frame 111, thereby protecting the lower housing assembly 1 and the internal cells of the power battery.

[0046] It should be noted that the number of longitudinal beams 19, front fixing points 13, middle fixing points 16, and rear fixing points 18 is determined according to the power battery layout scheme, with a preferred number of ≥2.

[0047] It should be noted that the longitudinal beam 19 includes integral and segmented forms, and the connection method between the longitudinal beam 19 and the lower box assembly 1 includes, but is not limited to, welding, bolting, and bonding.

[0048] It should be noted that the connection methods between the force-guided anti-collision beam 2 and the right side frame assembly 11, the left side frame assembly 14, and the front fixing point 13 include, but are not limited to, bolt connection, welding, and bonding.

[0049] like Figure 5 As shown, Figure 5 The left arrow indicates the direction of the collision. When the vehicle collides, the collision energy is first transferred to the force-guiding anti-collision beam 2. The force-guiding anti-collision beam conducts and distributes the collision energy to the left and right side frame assemblies and the longitudinal beam force transmission path. The force transmission paths of the left and right side frame assemblies include the symmetrically arranged left side frame assembly force transmission path 21 and right side frame assembly force transmission path 22. In the right side frame assembly force transmission path, the collision energy is conducted to the vehicle body through the frame fixing beam 112 and multiple connecting bushings 113. In the longitudinal beam force transmission path, the collision energy is conducted to the vehicle body sequentially through the front fixing point 13, the longitudinal beam 19, the middle fixing point 16, and the rear fixing point 18.

[0050] Example 2

[0051] This embodiment provides a lower housing design method for implementing the lower housing of Embodiment 1, including the following steps:

[0052] Step S1: Design the guiding angle η of the guiding force anti-collision beam 2, such as... Figure 1The guiding angle η shown is selected based on the arrangement and structural scheme. The principle of this invention is to conduct the vast majority of collision energy to the force transmission path. For example... Figure 5 As shown, the preferred range of the guiding angle n is 30°-75°;

[0053] Step S2: Design the cross-sectional structure of the force-guiding anti-collision beam 2, such as... Figure 4 As shown, the cross-sectional dimension w and longitudinal dimension l are determined according to the power battery layout space and protection requirements. The height of the force-guided anti-collision beam 2 is lower than the lowest point of the power battery, and the wall thickness t of the force-guided anti-collision beam 2 ranges from 1.0mm to 4mm.

[0054] Step S3: Design the guiding structure of the force-guided anti-collision beam 2 to enable it to have guiding function. The value range of the guiding angle d is 90°-150°. When the power battery scrapes the bottom or the front of the power battery is hit by bricks, manhole covers, etc., the collision will be guided to the bottom protection plate of the power battery.

[0055] Step S4: Connection design of the force-guiding anti-collision beam 2. It is connected to the frame fixing beam 112. The connection method includes, but is not limited to, welding, screwing, and bonding. The length of the frame fixing beam 112 is greater than that of the frame 111, ensuring that collision energy is transmitted to the vehicle body through the frame fixing beam 112 and the connecting bushing 113. Figure 3 As shown, the preferred length h is 1mm–20mm. The force-guiding anti-collision beam 2 is connected to the front fixing point 13, as shown. Figure 4 As shown, the connection methods include, but are not limited to, welding, screwing, and bonding; Figure 3 for Figure 1 The diagram shows the structure of the enlarged section I.

[0056] Step S5: Collision force transmission path design, such as Figure 5 As shown. The force transmission paths of the left and right frame assemblies include a symmetrically arranged force transmission path 21 for the left frame assembly and a force transmission path 22 for the right frame assembly. In the force transmission paths of the left and right frame assemblies, the collision energy is first transmitted to the force guiding anti-collision beam 2. The force guiding anti-collision beam 2 conducts and distributes the collision energy to the left and right frame assemblies. Taking the right frame assembly 11 as an example, the collision energy is transmitted to the vehicle body through the frame fixing beam 112 and multiple connecting bushings 113. The force transmission path of the left and right frames is: force guiding anti-collision beam 2 → frame fixing beam 112 → connecting bushings 113 → vehicle body. In the longitudinal beam force transmission path, the longitudinal beam 19, the front fixing point 13, the middle fixing point 16, and the rear fixing point 18 are arranged on the same axis in the left and right direction (the Y direction of the whole vehicle). The collision energy is transmitted to the vehicle body through the front fixing point 13, the longitudinal beam 19, the middle fixing point 16, and the rear fixing point 18. The force transmission path of the longitudinal beam is as follows: force guiding anti-collision beam 2 → front fixed point 13 → longitudinal beam 19 → middle fixed point 16, rear fixed point 18 → vehicle body;

[0057] Step S6: Energy absorption zone design, such asFigure 4 As shown, a first energy-absorbing zone a is designed between the force-guiding anti-collision beam 2 and the front frame assembly 12, and a second energy-absorbing zone b is designed inside the front frame assembly 12, forming a two-stage energy absorption buffer for collision energy. Based on the specific layout of the power battery and protection requirements, a = 50mm-120mm and b = 30mm-200mm are preferably selected. The first energy-absorbing zone a and the second energy-absorbing zone b can be filled with buffer material to enhance the energy absorption effect.

[0058] Step S7: High-strength cutoff structure design, such as Figure 4 As shown, based on the power battery structure and protection requirements, the front frame assembly 12 is equipped with a high-strength cutoff structure to interrupt energy absorption and collapse deformation, protecting the internal cells of the power battery from damage.

[0059] Example 3

[0060] This embodiment provides a power battery, including battery cells and a lower housing, wherein the battery cells are installed in the lower housing.

[0061] The technical solution provided in this application has a simple structure and strong adaptability, and is fully compatible with power batteries of all materials and cell types.

[0062] Finally, it should be noted that the above embodiments are merely illustrative and explanatory of the present invention, and are not intended to limit the present invention to the scope of the described embodiments. Furthermore, those skilled in the art will understand that the present invention is not limited to the above embodiments, and many more variations and modifications can be made based on the teachings of the present invention, all of which fall within the scope of protection claimed by the present invention.

Claims

1. A lower housing, said lower housing being used for a power battery, characterized in that, It includes a lower box assembly (1) and a force-guided anti-collision beam (2), wherein the force-guided anti-collision beam (2) is arranged in front of the lower box assembly (1); when a collision occurs, the collision energy is first transferred to the force-guided anti-collision beam (2), and the force-guided anti-collision beam (2) conducts and distributes the collision energy to the lower box assembly (1) and the vehicle body in sequence.

2. The lower housing according to claim 1, characterized in that, The guiding anti-collision beam (2) is designed with a guiding structure, and the height of the guiding anti-collision beam (2) is lower than the lowest point of the power battery; when the power battery scrapes the bottom or collides with the front of the power battery, the collision will be guided to the bottom guard plate of the power battery.

3. A lower housing according to claim 2, characterized in that, The guide angle (d) of the guide structure ranges from 90° to 150°.

4. A lower housing according to claim 1, characterized in that, The lower housing assembly (1) includes a right side frame assembly (11), a front frame assembly (12), a left frame assembly (14), and a rear frame assembly (17) connected in a square shape; the force-guiding anti-collision beam (2) is connected to the right side frame assembly (11) and the left frame assembly (14), and a first energy-absorbing zone (a) is designed between it and the front frame assembly (12), and a second energy-absorbing zone (b) is designed inside the front frame assembly (12), forming a two-level energy-absorbing buffer collision energy.

5. A lower housing according to claim 4, characterized in that, The first energy-absorbing zone (a) and the second energy-absorbing zone (b) are filled with cushioning material.

6. A lower housing according to claim 4, characterized in that, The front frame assembly (12) weakens the strength of the second energy absorption zone (b), so that it can collapse and absorb energy during a collision. At the same time, a high-strength cutoff structure is designed to cut off the collapse deformation and form protection for the inside of the power battery.

7. A lower housing according to claim 1, characterized in that, The lower housing assembly (1) also includes a front fixing point (13), a crossbeam (15), a middle fixing point (16), a rear fixing point (18), and a longitudinal beam (19); the force-guiding anti-collision beam (2) is also connected to the front fixing point (13); the front fixing point (13), the middle fixing point (16), and the rear fixing point (18) are connected to the vehicle body, and the longitudinal beam (19), the front fixing point (13), the middle fixing point (16), and the rear fixing point (18) are located on the left side. The right side is arranged on the same axis; the left side frame assembly (14) and the right side frame assembly (11) are symmetrical; the right side frame assembly (11) includes a frame (111), a frame fixing beam (112) and a connecting bushing (113); the right side frame is connected to the vehicle body through the frame fixing beam (112) and the connecting bushing (113); the frame fixing beam (112) is connected to the force-guiding anti-collision beam (2), and the length of the frame fixing beam (112) is greater than that of the frame (111).

8. A lower housing according to claim 7, characterized in that, When the vehicle is involved in a collision, the collision energy is first transferred to the force-guiding anti-collision beam (2). The force-guiding anti-collision beam conducts and distributes the collision energy to the left and right side frame assemblies and the longitudinal beam force transmission path. The force transmission path of the left and right side frame assemblies includes the symmetrically arranged left side frame assembly force transmission path and right side frame assembly force transmission path. In the right side frame assembly force transmission path, the collision energy is conducted to the vehicle body through the frame fixing beam (112) and multiple connecting bushings (113). The longitudinal beam force transmission path is that the collision energy is conducted to the vehicle body through the front fixing point (13), longitudinal beam (19), middle fixing point (16), and rear fixing point (18) in sequence.

9. A method for designing a lower housing, used to implement the lower housing as described in any one of claims 1-8, characterized in that, Includes the following steps: Step S1: Design the guiding angle (n) of the guiding force anti-collision beam (2). The value range of the guiding angle (n) is 30°-75°, which is used to transmit the collision energy to the force transmission path. Step S2: Design the cross-sectional structure of the force-guided anti-collision beam (2). The cross-sectional dimensions (w) and longitudinal dimensions (l) are determined based on the power battery layout space and protection requirements. The height of the force-guided anti-collision beam (2) is lower than the lowest point of the power battery. The wall thickness (t) of the force-guided anti-collision beam (2) is in the range of 1.0mm-4mm. Step S3: Design the guiding structure of the force-guided anti-collision beam (2). The value range of the guiding angle (d) is 90°-150°. When the power battery scrapes the bottom or the front of the power battery collides, the collision will be guided to the bottom guard plate of the power battery. Step S4: Connect the force-guided anti-collision beam (2) to the frame fixing beam (112) and the front fixing point (13). The length of the frame fixing beam (112) is greater than that of the frame (111), and the length (h) of the frame fixing beam (112) extending beyond the frame (111) is 1mm-20mm. Step S5: Design the collision force transmission path, including the force transmission path of the left and right frame assemblies and the force transmission path of the longitudinal beams; the force transmission path of the left and right frame assemblies includes the symmetrically arranged force transmission path of the left frame assembly and the force transmission path of the right frame assembly, wherein the force transmission path of the right frame assembly is the force guiding anti-collision beam (2) → frame fixing beam (112) → connecting bushing (113) → vehicle body; the force transmission path of the longitudinal beams is the force guiding anti-collision beam (2) → front fixing point (13) → longitudinal beam (19) → middle fixing point (16), rear fixing point (18) → vehicle body; Step S6: Design the first energy absorption zone (a) and the second energy absorption zone (b). The width of the first energy absorption zone (a) is 50mm-120mm, and the width of the second energy absorption zone (b) is 30mm-200mm. Filling buffer material is placed in the first energy absorption zone (a) and the second energy absorption zone (b). Step S7: The front frame assembly (12) weakens the strength of the second energy absorption zone (b), so that it can collapse and absorb energy during a collision. At the same time, a high-strength cut-off structure is designed to cut off the collapse deformation and form protection for the inside of the power battery.

10. A power battery, characterized in that, It includes battery cells and a lower housing as described in any one of claims 1-8, wherein the battery cells are installed in the lower housing.

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