CN214625180U

CN214625180U - Battery module with thermal runaway safeguard function

Info

Publication number: CN214625180U
Application number: CN202120473673.4U
Authority: CN
Inventors: 何帆; 李小辉; 凌生斌; 朱斌; 吴庆; 李林阳; 鲁恒飞; 岑波; 田晓薇
Original assignee: Gotion High Tech Co Ltd
Current assignee: Gotion High Tech Co Ltd
Priority date: 2021-03-03
Filing date: 2021-03-03
Publication date: 2021-11-05
Anticipated expiration: 2031-03-03

Abstract

The utility model discloses a battery module with thermal runaway protection function in the battery field, which comprises an upper shell, a lower shell and a middle battery cell stacking assembly, wherein the battery cell stacking assembly comprises at least two groups of battery cell units which are stacked side by side along the left and right direction, and each group of battery cell unit comprises at least one battery cell; the left side and the right side of the electric core unit are both provided with a heat insulation layer, heat conduction glue is arranged between the bottom and the inner bottom surface of the lower shell, and the front end part and the rear end part of the heat conduction glue are provided with rubber pads fixed on the inner bottom surface of the lower shell; a mica upper cover plate is arranged between the battery cell stacking assembly and the upper shell, and the periphery of the mica upper cover plate is bent downwards and completely covers the upper edge of the battery cell stacking assembly. The utility model discloses can block up around electric core unit, prevent that single electric core unit from catching fire and destroying other electric core units and the peripheral bearing structure of external copper bar installation face etc. reach good effect that prevents the thermal runaway.

Description

Battery module with thermal runaway safeguard function

Technical Field

The utility model relates to a battery field specifically is a battery module with thermal runaway safeguard function.

Background

The battery module made of the NCM ternary soft package power battery is widely used due to high energy density. Generally set up multiunit electric core unit in the battery module, according to the customer's demand, set up the three-dimensional laminate polymer core of a plurality of quantity in a set of electric core unit. The ternary soft package battery cell is easy to generate thermal runaway and even fire under abnormal conditions caused by various reasons such as overcharge, overheating, internal short circuit, extrusion, impact and the like. After a single electric core is on fire, the thermal runaway of other electric cores in the electric core unit can be caused, the thermal runaway of other electric core units is caused inside the module, and then the thermal runaway of the whole module is caused to cause the fire or even the explosion, so that the safety of personnel in the whole vehicle and the vehicle is threatened. Therefore, how to prevent and delay the occurrence of thermal runaway of the battery module becomes a problem.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a battery module with thermal runaway safeguard function to solve the problem that proposes in the above-mentioned background art.

In order to achieve the above object, the utility model provides a following technical scheme:

a battery module with a thermal runaway protection function comprises an upper shell and a lower shell, wherein the upper shell and the lower shell are fixedly connected to form a cavity with a circumferential side surface closed, a battery cell stacking assembly is arranged in the cavity, the battery cell stacking assembly comprises at least two groups of battery cell units which are stacked side by side along the left-right direction, and each group of battery cell units comprises at least one battery cell; the left side and the right side of the electric core unit are both provided with a heat insulation layer, heat conduction glue is arranged between the bottom and the inner bottom surface of the lower shell, and the front end part and the rear end part of the heat conduction glue are provided with rubber pads fixed on the inner bottom surface of the lower shell; a mica upper cover plate is arranged between the battery cell stacking assembly and the upper shell, and the periphery of the mica upper cover plate is bent downwards and completely covers the upper edge of the battery cell stacking assembly.

As an improvement of the present invention, in order to further prevent the battery from affecting the external environment when the battery is on fire, the front end and the rear end of the battery cell stacking assembly are respectively provided with a front end cover and a rear end cover which are fixedly connected with the upper casing and the lower casing; the mica upper cover plate comprises an upper plate, a front turned edge for blocking the joint of the front end cover and the upper shell is arranged on the front side of the upper plate, a rear turned edge for blocking the joint of the rear end cover and the upper shell is arranged on the rear side of the upper plate, and side turned edges for respectively wrapping the edges above the battery cores at the left end and the right end are arranged on the left side and the right side of the upper plate.

As an improvement of the present invention, in order to improve the heat insulation effect between the cell units, the heat insulation layer is a first heat insulation layer, a second heat insulation layer or a third heat insulation layer; the first heat insulation layer is an aerogel cushion and is arranged between the two adjacent groups of the battery cell units; the second heat insulation layer is a composite heat insulation layer consisting of a mica side plate and foam cotton and is arranged between the battery cell unit and the left and right inner side walls of the lower shell; the third insulating layer is a foam layer, is arranged in the middle of the battery cell stacking assembly, and is divided equally into the battery cell units with the same number.

As the utility model discloses an improvement scheme, in order to strengthen the protection to battery module and circuit board, be provided with the FPC assembly between mica upper cover plate and the epitheca, and set up the NTC patchhole that makes the FPC assembly be connected with electric core on the mica upper cover plate, NTC patchhole coats and is stamped the mica patch.

As an improvement scheme of the utility model, tab supports are arranged between the front end and the front end cover and between the rear end and the rear end cover of the cell stacking assembly, copper bars are fixed on the tab supports, and the copper bars are connected with the electrode leading-out ends of each cell; in order to further improve the insulation safety performance, an insulation cover is arranged between the lug support and the copper bar and is installed on the lug support through a buckle, and avoidance parts are respectively arranged on the front end cover, the rear end cover and the insulation cover corresponding to the installation parts of the copper bar on the front side and the rear side.

As the utility model discloses an improvement scheme, for further protection copper bar, prevent that the front end housing of copper bar and module, rear end cap contact from leading to the module short circuit, still include copper bar ceramic sheath, copper bar ceramic sheath adopts embedded structure to install the position of dodging at the insulating boot corresponding copper bar installation position.

As the improved scheme of the utility model, in order to facilitate the air current that produces when discharging the thermal runaway, the air guide hole has all been seted up on front end housing, rear end cap, insulating boot and the utmost point ear support.

As the utility model discloses an improvement scheme, for reinforcing fire behavior, epitheca, inferior valve are the sheet metal component, through welded fastening, and the medial surface of epitheca orientation electric core stack assembly scribbles the fire prevention lacquer, and the medial surface of inferior valve orientation electric core stack assembly scribbles insulating varnish.

As the utility model discloses an improvement scheme, for reinforcing fire behavior, front end housing, rear end cap are the die casting, all pass through welded fastening with epitheca, inferior valve, and all are scribbled insulated paint on front end housing, rear end cap towards electric core stack assembly's the medial surface.

As the utility model discloses an improvement scheme, in order to keep lasting of data acquisition when thermal runaway, the FPC assembly includes the main connector, the ceramic sheath of main connector is installed to utmost point ear support, and the parcel of main connector ceramic sheath the main connector is just to the face of electric core.

Has the advantages that: when single electric core unit takes place the thermal runaway trouble, the inside air current that produces of module, smog, mars and flame, the utility model discloses can prevent to catch fire the welding seam of back flame destruction module, front end housing, rear end cap and epitheca through the mica upper cover plate, prevent that flame from influencing other electric core units and the peripheral bearing structure of external copper bar installation face etc. through the thermal-conducting resin of insulating layer and the bottom on left and right sides, because all around of electric core unit by the shutoff, consequently can reach good delay, prevent the effect of thermal runaway.

Drawings

Fig. 1 is a schematic view of the overall external structure of the present invention;

fig. 2 is a schematic diagram of the explosion structure of the present invention;

FIG. 3 is a schematic structural view of the mica upper cover plate of the present invention;

fig. 4 is a schematic structural view of the tab holder of the present invention;

fig. 5 is a schematic structural view of the tab holder of the present invention when connected to the insulating cover;

fig. 6 is a schematic structural view of the tab holder of the present invention when connected to the insulating cover and the front end cap.

In the figure: 1-upper shell; 2-a lower shell; 3-front end cover; 4-rear end cap; 5-electric core; 6-a third insulating layer; 7-a first thermally insulating layer; 8-a second thermally insulating layer; 9-copper bar; 10-a tab support; 11-an insulating cover; 12-mica upper cover plate; 1201-front crimping; 1202-side hemming; 1203-upper plate; 1204-rear curling; 1205-NTC insertion hole; 13-rubber pad; 14-heat conducting glue; 15-copper bar ceramic sheath; 16-main connector ceramic sheath; 17-mica patches; 18-FPC; 19-main connector.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.

Referring to fig. 1-2, a battery module with thermal runaway safeguard function, includes epitheca 1 and inferior valve 2, epitheca 1, inferior valve 2 fixed connection constitute circumference side confined cavity, are provided with electric core stack assembly in the cavity, and as an preferred embodiment, epitheca 1 is the sheet metal component with inferior valve 2, through welded fastening, the medial surface of epitheca 1 towards electric core stack assembly all scribbles the fire prevention lacquer, and inferior valve 2 scribbles the insulating varnish towards the medial surface of electric core stack assembly.

The battery cell stacking assembly comprises a plurality of groups of battery cell units stacked side by side along the left and right directions, and each group of battery cell units comprises at least one battery cell 5. The number of the battery cells 5 is set according to actual requirements, for example, the total number of the battery cells 5 is 24, the battery cell units are set to 6 groups, and a group of battery cell units comprises 4 stacked battery cells, so that the nominal voltage of 50V can be reached. The total number of the battery cells 5 may also be set to 20, 18, 12, etc.

The front end and the rear end of the battery cell stacking assembly are respectively provided with a front end cover 3 and a rear end cover 4. As a preferred embodiment, the front end cap 3 and the rear end cap 4 are die-cast parts, and are fixed to the upper casing 1 and the lower casing 2 by welding, and the inner sides of the front end cap 3 and the rear end cap 4 facing the cell stack assembly are coated with insulating varnish for improving the electrical insulation performance of the battery module.

As shown in fig. 4-6, tab supports 10 are disposed between the front end of the cell stacking assembly and the front end cap 3, and between the rear end of the cell stacking assembly and the rear end cap 4, the tab supports 10 are plastic open-type components, copper bars 9 are fixed above the tab supports, and the copper bars 9 are connected to electrode leading-out ends of each cell.

The left side and the right side of the battery cell unit 5 are respectively provided with a heat insulation layer, specifically, the heat insulation layer may be a first heat insulation layer 7, a second heat insulation layer 8 or a third heat insulation layer 6. The inner space of the battery module is limited, and every two battery cores 5 cannot be isolated by the heat-insulating layer, so that the first heat-insulating layer 7 is arranged between every two adjacent battery core units, and the first heat-insulating layer 7 is an aerogel pad and used for preventing the battery core assembly of other groups from being influenced when the thermal runaway of the single-group battery core assembly is prevented. In order to prevent the flame from burning the cavity formed by the upper shell 1 and the lower shell 2 from inside to outside, the second heat insulation layer 8 is a composite heat insulation layer formed by mica side plates and foam cotton, and is arranged between the battery cell unit and the left inner side wall and the right inner side wall of the cavity to play a protection role. Third insulating layer 6 is the cotton layer of bubble, sets up in the middle of electric core stack assembly, divides the electric core unit of each 6 groups about dividing equally, and when 5 operation inflation of electric core, the pressure that receives of the left and right surface (the surface area is the biggest) of electric core 5 is very big, consequently adopts cotton 6 of bubble to cushion, also can play thermal-insulated effect. The composite heat insulation layer, the aerogel pad and the foam layer can prevent flame and high temperature from burning through and melting the side surface of the lower shell 2 of the module and the welding line between the upper shell 1 and the lower shell 2 from inside to outside.

And a heat-conducting glue 14 is arranged between the bottom of the battery cell 5 and the inner bottom surface of the lower shell 2, and the heat-conducting glue 14 plays a role in protecting the bottom of the battery cell 5. The front end and the rear end of the heat conducting glue 14 are provided with rubber pads 13 fixed on the inner bottom surface of the lower shell 2, the rubber pads 13 are used for preventing the heat conducting glue 14 from overflowing from the bottoms of the front end cover 3 and the rear end cover 4, and the bent sharp corners at the front edge and the rear edge of the bottom of the battery cell 5 can be protected from being broken due to abrasion with the lower shell 2 to cause liquid leakage.

A mica upper cover plate 12 is arranged between the battery cell stacking assembly and the upper shell 1, the mica upper cover plate 12 is a die sinking component, and the periphery of the mica upper cover plate is bent downwards and completely covers the upper edge of the battery cell stacking assembly. Specifically, as shown in fig. 3, the mica upper cover plate 12 includes an upper plate 1203, a front curled edge 1201 is provided on the front side of the upper plate 1203, a rear curled edge 1204 is provided on the rear side, and side curled edges 1202 are provided on the left and right sides, respectively. The front curled edge 1201 covers and blocks the joint of the front end cover 3 and the upper shell 1, the rear curled edge 1204 covers and blocks the joint of the rear end cover 4 and the upper shell 1, the left side curled edge 1202 on the left side wraps the left edge above the battery cell 5 on the left end (the left edge and the right edge of the battery cell 5 adopt a smooth design and are in an arc surface), and the right side curled edge 1202 on the right side wraps the right edge above the battery cell 5 on the right end. The upper ends of the tab brackets 10 are also covered by the front curled edges 1201 and the rear curled edges 1204, so that flame is prevented from damaging the supporting structure on the periphery of the copper bar mounting surface and the welding seams of the front end cover 3, the rear end cover 4 and the upper shell 1.

Therefore, in the battery module, the top of all the electric core units is covered by the upper plate 1203, the bottom is protected by the heat conducting glue 14, the welding seams of the exposed upper shell 1 and the upper end cover 3 are shielded by the front turned edge 1201, the welding seams between the rear end cover 4 and the upper shell 1 are shielded by the rear turned edge 1204, the side turned edges 1202 at the two sides cover the upper side bending edges of the electric core 5 at the left and right ends, and the middle electric core units are flame-retardant and isolated through the aerogel pads. When a certain battery cell 5 in the module is ignited, the front curled edge 1201, the rear curled edge 1204, the side curled edge 1202, the upper plate 1203, the third heat insulation layer 6, the first heat insulation layer 7, the second heat insulation layer 8 and the heat conduction glue 14 are matched, flame is limited at the battery cell unit on fire, and the flame is prevented from affecting other battery cell units and the whole battery module from inside to outside. The upper plate 1203 cooperates with the fire-retardant paint on the inner side of the upper shell 1 to prevent flames and high temperature from burning through and melting the module upper shell 1.

An FPC assembly is arranged between the mica upper cover plate 12 and the upper shell 1, and the FPC assembly comprises an FPC 18, a main connector 19, a PCB, an NTC (negative temperature coefficient) thermistor, NTC protective foam, a welding nickel sheet, a safety device and the like. The upper plate 1203 is provided with an NTC insertion hole 1205 for connecting the FPC assembly to the electric core 5, and the NTC insertion hole 1205 is covered with a mica patch 17. The mica patch 17 prevents the upper case 1 from being damaged by flame and high temperature through the NTC insertion hole 1205.

In a preferred embodiment, an insulating cover 11 is arranged between the tab support 10 and the copper bar 9, and the insulating cover 11 is likewise a plastic split-die piece. The insulating cover 11 is installed on the lug support 10 through a buckle and used for enhancing the electrical insulating performance of the module, and avoidance parts are respectively arranged on the front end cover 3, the rear end cover 4 and the insulating cover 11 corresponding to the installation parts of the copper bars 9 on the front side and the rear side.

As a preferred embodiment, in order to protect the plastic of the leading-out electrode of the copper bar 9 from being damaged by flame and high temperature within a period of time, the copper bar 9 is in contact with the front end cover 3 to cause short circuit outside the module, the copper bar 9 is protected by the copper bar ceramic sheath 15, the copper bar ceramic sheath 15 is a die sinking piece, adopts an embedded structure, and is installed at an avoiding position of the insulating cover 11 corresponding to the installation position of the copper bar 9.

In a preferred embodiment, the tab support 10 is provided with a main connector ceramic sheath 16, and the main connector ceramic sheath 16 is an open mold and wraps the surface of the main connector 19, which faces the battery cell 5. When the battery module is in thermal runaway, the main connector ceramic sheath 16 protects the main connector 19 from being damaged by flame and high temperature for a period of time, so that the data acquisition function of the module can still be kept normal for a period of time after the thermal runaway occurs.

As a preferred embodiment, in order to reduce the explosion risk of the battery module in thermal runaway, air vents are formed in the front end cover 3, the rear end cover 4, the insulating cover 11 and the tab support 10. When the battery module thermal runaway trouble appears, when battery module inside production air current, smog, mars and flame need outside blowout, through the air guide hole discharge of front end housing 3 and rear end housing 4, prevent that the module internal gas pressure from too big producing the explosion, the air guide hole of utmost point ear support 10 and the air guide hole of insulating boot 11 ensure that the escape route is unobstructed, do not blockked by the material that the burning produced.

The utility model discloses well electric core unit all around by the shutoff, can reach good effect that prevents the thermal runaway.

Although the present description is described in terms of embodiments, not every embodiment includes only a single embodiment, and such description is for clarity only, and those skilled in the art should be able to integrate the description as a whole, and the embodiments can be appropriately combined to form other embodiments as will be understood by those skilled in the art.

Therefore, the above description is only a preferred embodiment of the present application, and is not intended to limit the scope of the present application; all changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.

Claims

1. A battery module with a thermal runaway protection function comprises an upper shell (1), a lower shell (2) and a middle battery cell stacking assembly, wherein the battery cell stacking assembly comprises at least two groups of battery cell units which are stacked side by side along the left and right directions, and each group of battery cell units comprises at least one battery cell (5); the battery is characterized in that the left side and the right side of the battery cell unit are both provided with a heat insulation layer, heat conduction glue (14) is arranged between the bottom and the inner bottom surface of the lower shell (2), and rubber pads (13) fixed on the inner bottom surface of the lower shell (2) are arranged at the front end part and the rear end part of the heat conduction glue (14); a mica upper cover plate (12) is arranged between the battery cell stacking assembly and the upper shell (1), and the periphery of the mica upper cover plate (12) is bent downwards and completely covers the upper edge of the battery cell stacking assembly.

2. The battery module with the thermal runaway protection function according to claim 1, wherein a front end cover (3) and a rear end cover (4) fixedly connected with the upper casing (1) and the lower casing (2) are respectively arranged at the front end and the rear end of the cell stacking assembly; the mica upper cover plate (12) comprises an upper plate (1203), a front curled edge (1201) for blocking the joint of the front end cover (3) and the upper shell (1) is arranged on the front side of the upper plate (1203), a rear curled edge (1204) for blocking the joint of the rear end cover (4) and the upper shell (1) is arranged on the rear side, and side curled edges (1202) for respectively wrapping the upper edges of the battery cores (5) at the left end and the right end are arranged on the left side and the right side.

3. The battery module with the thermal runaway protection function according to claim 1, characterized in that the thermal insulation layer comprises a first thermal insulation layer (7), a second thermal insulation layer (8) and a third thermal insulation layer (6); the first heat insulation layer (7) is an aerogel cushion and is arranged between the two adjacent groups of the battery cell units; the second heat insulation layer (8) is a composite heat insulation layer consisting of a mica side plate and foam cotton and is arranged between the battery cell unit and the left and right inner side walls of the lower shell; and the third heat insulation layer (6) is a foam layer, is arranged in the middle of the battery cell stacking assembly and is equally divided into the left battery cell unit and the right battery cell unit with the same number.

4. The battery module with the thermal runaway protection function as claimed in claim 2, wherein an FPC assembly is arranged between the mica upper cover plate (12) and the upper shell (1), an NTC insertion hole (1205) for connecting the FPC assembly with the battery core (5) is formed in the mica upper cover plate (12), and the NTC insertion hole (1205) is covered with a mica patch (17).

5. The battery module with the thermal runaway protection function according to claim 4, wherein tab brackets (10) are arranged between the front end of the cell stacking assembly and the front end cover (3) and between the rear end of the cell stacking assembly and the rear end cover (4), copper bars (9) are fixed on the tab brackets (10), and the copper bars (9) are connected with electrode leading-out ends of the cells; be equipped with between utmost point ear support (10) and copper bar (9) insulating boot (11), insulating boot (11) are installed on utmost point ear support (10) through the buckle, correspond the installation position of front and back both sides copper bar (9) on front end housing (3), rear end cap (4), insulating boot (11) and have seted up respectively and dodge the position.

6. The battery module with the thermal runaway protection function according to claim 5, further comprising a copper bar ceramic sheath (15), wherein the copper bar ceramic sheath (15) adopts an embedded structure and is installed at an avoiding part of the insulation cover (11) corresponding to the installation part of the copper bar (9).

7. The battery module with the thermal runaway protection function as claimed in claim 5, wherein the FPC assembly comprises a main connector (19), a main connector ceramic sheath (16) is mounted on the tab support (10), and the main connector ceramic sheath (16) wraps the surface, facing the battery cell (5), of the main connector (19).

8. The battery module with the thermal runaway protection function as claimed in claim 5, wherein the front end cover (3), the rear end cover (4), the insulation cover (11) and the tab support (10) are all provided with air vents.

9. The battery module with the thermal runaway protection function according to claim 2, wherein the front end cover (3) and the rear end cover (4) are die-cast parts and are fixed to the upper casing (1) and the lower casing (2) by welding, and insulating paint is coated on inner side surfaces, facing the cell stack assembly, of the front end cover (3) and the rear end cover (4).

10. The battery module with the thermal runaway protection function of claim 1, wherein the upper casing (1) and the lower casing (2) are sheet metal parts and are fixed by welding, the inner side surface of the upper casing (1) facing the battery cell stacking assembly is coated with fireproof paint, and the inner side surface of the lower casing (2) facing the battery cell stacking assembly is coated with insulating paint.