Solid-state battery module and solid-state battery pack

Abstract

The utility model provides a solid-state battery module and a solid-state battery pack, the solid-state battery module comprises a shell, a battery stacking body and a stress rod, the battery stacking body and the stress rod are arranged in the shell, the shell comprises two end plates, and the two end plates are oppositely arranged; one end of the stress rod is connected with the end plate, the other end of the stress rod penetrates through the battery stacking body and is connected with the other end plate, and the stacking direction of the battery stacking body is the length direction of the stress rod. According to the utility model, the clamping stress of the end plate on the solid-state battery can be balanced, so that the solid-state battery module is light in weight.

Description

TECHNICAL FIELD

[0001] The utility model relates to solid state battery technical field especially relates to a kind of solid state battery module and solid state battery package. BACKGROUND

[0002] The solid-state electrolyte of solid-state battery needs to be in direct contact with the positive and negative electrode materials to conduct electricity. During the charging and discharging process of the solid-state battery, the negative electrode material undergoes volume change, resulting in a gap between the solid-state electrolyte and the negative electrode material, and the conductivity decreases.

[0003] To maintain electrical contact between the solid-state electrolyte and the positive active material, as well as between the solid-state electrolyte and the negative active material, a large external pressure needs to be applied during the use of the solid-state battery to maintain contact between the solid-state electrolyte and the positive and negative electrode materials. The external pressure is usually up to 300 MPa, which requires a thick clamping structure on the two main surfaces of the solid-state battery. However, a thick clamping structure will reduce the energy density of the solid-state battery package.

[0004] The invention with publication number CN114865205A discloses a solid-state battery module and a battery package. The solid-state battery module includes a shell and a cell stack body arranged inside the shell. The shell includes a top plate, a bottom plate, and two end plates. The top plate and the bottom plate are arranged oppositely. The two end plates are connected between the top plate and the bottom plate, and are arranged oppositely. At least one end plate can move relative to the top plate and the bottom plate in a first direction, which is the stacking direction of the cell stack body. However, during the charging and discharging process of the above-mentioned solid-state battery, there is a volume change, which will cause a gap between the solid-state electrolyte and the negative electrode material, and the conductivity decreases. SUMMARY

[0005] The utility model aims to solve the defects in the prior art and provides a solid-state battery module and a solid-state battery package. The clamping stress of the end plate on the solid-state battery is balanced, and the solid-state battery module is lightweight.

[0006] To achieve the above-mentioned purpose, the utility model provides a solid-state battery module, which includes a shell, a battery stack body arranged inside the shell, and a stress rod. The shell includes two end plates, and the two end plates are arranged oppositely.

[0007] One end of the stress rod is connected with the end plate, and the other end passes through the battery stack body and is connected with the other end plate. The stacking direction of the battery stack body is the length direction of the stress rod.

[0008] The thickness of the battery stack changes during the charging and discharging process, the stress generated by the thickness change of the battery stack forms a pressing force on the two end plates, the two end plates form a pulling force on the side plate, the top plate and the bottom plate, and the thickness of the battery stack in different areas changes differently, the thickness of part of the area of the battery stack changes more greatly, which further aggravates the deformation of the area where the two end plates are stressed more, and even causes the connection between the end plate and the side plate, the top plate and the bottom plate to fail, and there is a pressure difference between the area where the two end plates are stressed more and the area where the two end plates are stressed less.

[0009] The utility model discloses a stress rod is arranged between two end plates, when the thickness of battery stack changes, the both ends of stress rod are fixedly connected with two end plates respectively, make stress rod pull two end plates, reduce the area where two end plates are stressed more greatly and deform, stress rod directly bears the pressure of battery stack, equivalent to the pressure is transferred to the area where end plate is stressed less, shorten the stress arm, thereby play the effect of balancing the clamping stress of solid -state battery of end plate, i. e. the stress of two end plates is adjusted to two end plates and intermediate stress, reduce the pulling force of two end plates on side plate, top plate and bottom plate, and reduce the setting clamping mechanism outside end plate, make solid -state battery module light weight, thereby improve solid -state battery package energy density.

[0010] Optionally, the battery stack includes a plurality of batteries, and each battery is provided with a through hole for the stress rod to pass through.

[0011] Optionally, the battery includes an outer packaging edge and a central packaging portion, and the through hole is arranged on the central packaging portion.

[0012] Optionally, the stress rod is threadedly connected with the end plate.

[0013] Optionally, both ends of the stress rod are provided with threads, and the corresponding positions of the two end plates are provided with screw holes.

[0014] When the stress rod is connected with the end plate through a threaded nut, both ends of the stress rod are provided with threads, and the two ends of the stress rod pass through the end plate, the corresponding positions of the two end plates are provided with screw holes, the stress rod is screwed into the screw hole of the end plate, and the nut is screwed into the end of the stress rod.

[0015] Optionally, the stress rod is welded with the end plate.

[0016] Optionally, the stress rod is connected with the center of the end plate.

[0017] Generally, the thickness of the battery changes during the charging and discharging process, the thickness of the middle area of the battery changes more greatly, which aggravates the deformation of the middle area of the end plate, and there is a pressure difference between the middle area and the surrounding area of the end plate, so the stress rod is connected to the central area of the two end plates and directly bears the middle pressure of the battery.

[0018] Advantages:

[0019] The thickness of the battery stack changes during the charging and discharging process, the stress generated by the thickness change of the battery stack forms a pressing force on the two end plates, the two end plates form a pulling force on the side plate, the top plate and the bottom plate, and the thickness of the battery stack in different areas changes inconsistently, the thickness of part of the area of the battery stack changes more greatly, which further aggravates the deformation of the area where the two end plates are stressed more, and even causes the connection between the end plate and the side plate, the top plate and the bottom plate to fail, and there is a pressure difference between the area where the two end plates are stressed more and the area where the two end plates are stressed less.

[0020] The utility model discloses a stress rod is arranged between two end plates, when the thickness of the battery stack changes, the stress rod two ends are fixedly connected with two end plates respectively, make the stress rod pull two end plates, reduce the area where two end plates are stressed more and deform, the stress rod directly bears the pressure of the battery stack, equivalent to the pressure transmission to the area where the end plate is stressed less, shorten the stress arm, thereby play the effect of balanced end plate to solid -state battery clamping stress, i. e. by two end plate stress adjustment is two end plate and intermediate stress, reduce the pulling force of two end plates on the side plate, the top plate and the bottom plate, and reduce the setting clamping mechanism outside the end plate, make solid -state battery module light weight, thereby improve solid -state battery package energy density. BRIEF DESCRIPTION OF DRAWINGS

[0021] In order to more clearly illustrate the technical scheme in the embodiments of the present application or the prior art, the drawings needed to be used in the following embodiment or prior art description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained according to the structures shown in these drawings without creative labor for those skilled in the art.

[0022] Figure 1 A structural diagram of a solid-state battery module is disclosed in the utility model.

[0023] Figure 2 A structural diagram of a battery in a solid-state battery module is disclosed in the utility model.

[0024] Reference signs: 1 housing; 2 end plate; 3 screw hole; 4 stress rod; 5 battery; 6 outer packaging edge; 7 center packaging part; 8 through hole.

[0025] The implementation, functional features and advantages of the utility model will be further described with reference to the embodiments and the drawings. DETAILED DESCRIPTION

[0026] The technical solutions in the embodiments of the present application will be clearly and completely described with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of the present application.

[0027] In the description of the present application, unless otherwise explicitly limited, the words such as setting, installing, connecting, etc. should be understood broadly, and the skilled in the art can reasonably determine the specific meaning of the above words in the present application in combination with the specific content of the technical solutions.

[0028] In the description of the present application, the description of the reference terms "one embodiment", "some embodiments", "illustrative embodiment", "example", "specific example" or "some examples" means that the specific features, structures, materials or characteristics described in combination with the embodiment or example are included in at least one embodiment or example of the present application. In the present specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the described specific features, structures, materials or characteristics can be combined in any one or more embodiments or examples in a suitable manner.

[0029] Embodiment 1:

[0030] Referring to Figure 1 and 2 According to the first embodiment of the present application, a solid-state battery module comprises a shell 1, a battery stack and a force rod 4 arranged in the shell 1, the shell 1 comprises two end plates 2, and the two end plates 2 are arranged opposite to each other.

[0031] One end of the force rod 4 is connected with the end plate 2, and the other end penetrates through the battery stack and is connected with the other end plate 2, and the stacking direction of the battery stack is the length direction of the force rod 4.

[0032] Specifically, the shell 1 comprises two end plates 2, two side plates, a top plate and a bottom plate, the upper and lower ends of the end plate 2 and the side plate are respectively connected with the top plate and the bottom plate, the two end plates 2 are arranged opposite to each other at the two ends of the battery stack along the stacking direction, and the two side plates are arranged opposite to each other at the two sides of the battery stack.

[0033] The thickness of the battery stack changes during the charging and discharging process, the stress generated by the thickness change of the battery stack forms a pressing force on the two end plates 2, the two end plates 2 form a pulling force on the side plate, the top plate and the bottom plate, and the thickness of the battery stack in different areas changes inconsistently, the thickness of part of the battery stack changes more greatly, which further aggravates the deformation of the area where the two end plates 2 are stressed more, and even causes the connection between the end plate 2 and the side plate, the top plate and the bottom plate to fail, and there is a pressure difference between the area where the two end plates 2 are stressed more and the area where the two end plates 2 are stressed less.

[0034] The utility model discloses a stress rod 4 is arranged between two end plates 2, when the thickness of the battery stack changes, the stress rod 4 is fixedly connected with two end plates 2 respectively at both ends, the stress rod 4 holds two end plates 2, reduces the area where two end plates 2 are stressed more and deforms, the stress rod 4 directly bears the pressure of the battery stack, equivalent to the pressure being transferred to the area where the end plate 2 is stressed less, and the stress arm is shortened, thereby the effect that the end plate 2 is balanced to the clamping stress of solid-state battery is achieved, that is, the stress of two end plates 2 is adjusted to the stress of two end plates 2 and the middle, the pulling force of two end plates 2 on the side plate, the top plate and the bottom plate is reduced, and the clamping mechanism is arranged outside the end plate 2, so that the solid-state battery module is lightened, thereby the energy density of solid-state battery pack is improved.

[0035] Referring to Figure 1 and 2 In some embodiments of the utility model, the battery stack includes a plurality of batteries 5, and each battery 5 is provided with a through hole 8 for the stress rod 4 to pass through. The batteries 5 are tightly attached to each other and are bonded by heat-conducting glue or double-sided adhesive tape. In order to better show the positional relationship between the stress rod 4 and the battery 5, Figure 1 The batteries in the battery stack are not all shown in the figure.

[0036] Referring to Figure 2 In some embodiments of the utility model, the battery 5 includes an outer packaging edge 6 and a center packaging part 7, and the through hole 8 is arranged on the center packaging part 7.

[0037] The electrode tab of the battery 5 is formed by die stamping. The through hole in the middle of the electrode tab can be formed together with the electrode tab or separately formed by die stamping. The electrode tab and the isolation film form a bare cell in a lamination manner. The through hole in the middle of the bare cell of the battery 5 can be formed by heat cutting the isolation film, wherein the through hole 8 in the middle of the isolation film is axially aligned with the through hole in the middle of the electrode tab.

[0038] During the aluminum plastic film stamping forming process of the battery 5, the outer shape of the center packaging part 7 is stamped and formed together. After the battery 5 and the aluminum plastic film are completed three-edge heat sealing packaging, the center packaging part 7 is heat sealed. By using a stamping die, the aluminum plastic film in the middle of the center packaging part 7 is cut off to form a through hole 8. After the battery 5 is completed, the subsequent process is performed to form an outer packaging edge 6.

[0039] Referring to Figure 1 In some embodiments of the utility model, the force bearing rod 4 is screwed with the end plate 2, or the force bearing rod 4 is welded with the end plate 2.

[0040] In the embodiment, the force bearing rod 4 is a metal rod, and the force bearing rod 4 is connected with the end plate 2 through laser welding or threaded nut.

[0041] Referring to Figure 1 In some embodiments of the utility model, the force bearing rod 4 is screwed with the end plate 2, or the force bearing rod 4 is welded with the end plate 2.

[0042] When the force bearing rod 4 is connected with the end plate 2 through the threaded nut, the force bearing rod 4 is screwed with the end plate 2, and the both ends of the force bearing rod 4 are threaded out of the end plate 2, the both ends of the force bearing rod 4 are screwed into the threaded hole 3 of the end plate 2 and threaded out of the end plate 2, and the nut is screwed into the end of the force bearing rod 4.

[0043] Referring to Figure 1 In some embodiments of the utility model, the force bearing rod 4 is screwed with the end plate 2, or the force bearing rod 4 is welded with the end plate 2.

[0044] Generally, the thickness of the battery 5 will change during the charging and discharging process, and the thickness of the middle region of the battery 5 will change more, which will aggravate the deformation of the middle region of the end plate 2, and there is a pressure difference between the middle region and the surrounding region of the end plate 2, so the force bearing rod 4 is connected to the central region of the two end plates 2 and directly bears the middle pressure of the battery 5.

[0045] Embodiment 2:

[0046] A solid-state battery module according to the second embodiment of the utility model, comprising a box body, and the above-mentioned solid-state battery module is arranged in the box body.

[0047] The above is only the preferred embodiment of the utility model, and does not limit the patent range of the utility model, and any equivalent structural transformation or direct / indirect application in other related technical fields under the utility model concept of the utility model is included in the patent protection range of the utility model.

Claims

1. A solid-state battery module, characterized by, The application relates to a solid-state battery module, comprising a shell, a battery stack and a force-bearing rod arranged in the shell, wherein the shell comprises two end plates arranged oppositely. One end of the force-bearing rod is connected with one end plate, and the other end of the force-bearing rod is connected with the other end plate through the battery stack, and the stacking direction of the battery stack is the length direction of the force-bearing rod.

2. The solid-state battery module of claim 1, wherein, The battery stack comprises a plurality of batteries, and each battery is provided with a through hole for the force-bearing rod to pass through.

3. The solid-state battery module of claim 2, wherein, The battery comprises an outer packaging edge and a central packaging part, and the through hole is arranged on the central packaging part.

4. The solid-state battery module of claim 1, wherein, The force-bearing rod is threadedly connected with the end plate.

5. The solid-state battery module of claim 3, wherein, Both ends of the force-bearing rod are provided with threads, and the two end plates are provided with screw holes at corresponding positions.

6. The solid state battery module of any one of claims 1-5, wherein, The force-bearing rod is welded with the end plate.

7. The solid state battery module of any one of claims 1-5, wherein, The force-bearing rod is connected with the center of the end plate.

8. A solid state battery pack characterized by, The application further relates to a solid-state battery module box, wherein the solid-state battery module as claimed in any one of claims 1-7 is arranged in the box.

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