BATTERY CASE CLOSING SYSTEM AND METHOD IMPLEMENTING SUCH A SYSTEM

Abstract

The invention relates to a system for assembling a battery case (1) intended for an electric or hybrid motor vehicle, said battery case comprising a first part (2a) and a second part (2b), said first part (2a) having a surface, said second part (2b) having a surface, the surface of the first part (2a) and the surface of the second part (2b) being in contact, the battery case (1) comprising a ventilation valve (3) adapted to ensure the evacuation of the air present inside said case (1), characterized in that said system comprises a means for bonding between the first part (2a) and the second part (2b) via their respective surfaces; a means for evacuating the battery case (1) by drawing air through said ventilation valve (3). Figure 1

Description

Title of the invention: BATTERY CASING CLOSING SYSTEM AND METHOD IMPLEMENTING SUCH A SYSTEM

[0001] The invention relates to electric or hybrid motor vehicles, in particular to the protection of their batteries.

[0002] Prior art is known French patent application FR3105596 describing a method for obtaining a thermal regulation device for at least one electrical or electronic component. This method is particularly applicable for the thermal regulation of a battery contained in a housing. The housing comprises a base and a lid covering said base. The battery is positioned in the base, on which the lid is placed. The base and the lid are joined by welding. A hydraulic coupler is incorporated into the housing wall. This coupler allows the connection of a vacuum system to the housing. Vacuuming is a method of extracting air from an enclosed space. The housing is therefore evacuated using this method. The housing is then filled with a two-phase dielectric fluid in the liquid phase.This type of fluid regulates the temperature of the cells that make up a vehicle's battery. When the vehicle is running or charging, the battery temperature rises, causing the fluid to change from a liquid to a gaseous state. This change of state occurs because heat is released into the casing as the battery warms up. The calorie is a unit of measurement for energy, similar to the joule. When the battery temperature drops, the heat is released back into the fluid, causing it to change from a gaseous to a liquid state. However, there are drawbacks. Initially, the casing was sealed by welding. This is a laborious process and requires considerable time, especially considering the number of casings that need to be welded.Furthermore, the injection of the two-phase dielectric fluid requires the installation of the hydraulic coupler in the housing wall, which could lead to a leak in the housing if mishandled or damaged.

[0003] The objective of the present invention is to remedy these drawbacks by proposing a quick-closing system for a battery case while ensuring the sealing of said case.

[0004] To achieve this objective, the invention proposes an assembly system for a battery case intended for an electric or hybrid motor vehicle, said battery case comprising a first part and a second part, said first part presenting a surface, said second part having a surface, the surface of the first part and the surface of the second part being in contact, the battery housing comprising a ventilation valve capable of ensuring the evacuation of the air present inside said housing, characterized in that said system comprises: - a means of bonding between the first part and the second part via their respective surfaces; - a means of evacuating the battery case by suction of air via said ventilation valve.

[0005] Thanks to the invention, the first part and the second part are assembled in such a way that the housing is effectively sealed. The battery contained in the housing is therefore not susceptible to damage due to the infiltration of a liquid that could cause a short circuit in the cells composing the vehicle's battery.

[0006] In addition, the surface of the first part and the surface of the second part are flat.

[0007] This configuration facilitates adhesion between the surface of the first part and the surface of the second part. This promotes better sealing of the housing during assembly.

[0008] Advantageously, the first part of the battery housing includes the ventilation valve.

[0009] The presence of the ventilation valve on the first part of the housing is more favorable for drawing air from the housing. Indeed, the first part is more easily accessible than the second part. Having the ventilation valve on the second part of the housing requires more steps during the design process, notably turning the housing over to access it. Furthermore, turning the housing over could damage the battery contained within it.

[0010] Advantageously, the ventilation valve has a diameter between 1 cm and 5 cm.

[0011] Such a diameter allows an efficient air aspiration flow for rapid vacuuming of the housing.

[0012] The invention also relates to a closing method implementing a battery case assembly system according to any one of claims 1 to 3, characterized in that said method comprises the following steps: - a step of gluing the first part of the battery case and the second part of the battery case by spreading glue on their respective surfaces; - a step of drawing air from the battery case by the ventilation valve, compressing the first part onto the second part of the case.

[0013] The invention will be further detailed by describing a non- limiting, and based on the attached figure the invention, in which [Fig.1] schematically illustrates a battery case for which a method of closing said case according to the present invention is implemented.

[0014] A battery housing is schematically illustrated in [Fig. 1]. The housing 1 comprises a first part 2a and a second part 2b. Inside the housing 1 is located a battery (not shown in the figure). The first part 2a has a surface (not shown in the figure). The second part 2b has a surface (not shown in the figure). When the first part 2a and the second part 2b are positioned one on top of the other, the surface of the first part 2a and the surface of the second part 2b are in contact. The first part 2a and the second part 2b may have several sections so that the contact areas between the first part 2a and the second part 2b are multiple. Preferably, the surface of the first part 2a and the surface of the second part 2b are flat so that their adhesion is facilitated and they promote better sealing. The first part 2a includes a vent valve 3.An air extractor 4 is connected to the ventilation valve 3. During a bonding step, glue is spread on the surface of the first part 2a and on the surface of the second part 2b. The air extractor 4 is positioned on the ventilation valve 3. When the air extractor 4 is in operation, the air inside the housing 1 is drawn out of the housing 1, passing through the air extractor 4. In [Fig. 1], the ventilation valve 3 is located on the first part 2a of said housing 1. When the air extractor 4 is in operation, a force is created to guide the air inside the housing 1 towards the air extractor 4 (in the direction indicated by the arrows in [Fig. 1]). The air is then expelled by the air extractor 4 into the environment around said box 1, without the air being able to re-enter said box 1.The vacuum sealing process removes at least 95%, or even 99%, of the air present within the housing 1. Vacuum sealing the housing 1 causes a decrease in pressure within the housing. This pressure reduction compresses the first part 2a and the second part 2b. This compression results in the application of two forces, directed from the outside to the inside of the housing, on the first part 2a and the second part 2b. These forces compress the first part 2a and the second part 2b, allowing the adhesive to be distributed evenly over the surface of both parts 2a and 2b. Thus, the first part 2a and the second part 2b are completely sealed at their respective surfaces. The housing 1 is therefore completely airtight.There is no risk of battery deterioration due to liquid seeping between the first part 2a and the second part 2b to enter the casing 1.

Claims

Claims

1. System for assembling a battery housing (1) intended for an electric or hybrid motor vehicle, said battery housing comprising a first part (2a) and a second part (2b), said first part (2a) having a surface, said second part (2b) having a surface, the surface of the first part (2a) and the surface of the second part (2b) being in contact, the battery housing (1) comprising a ventilation valve (3) capable of ensuring the evacuation of the air present inside said housing (1), characterized in that said system comprises: - a means of bonding between the first part (2a) and the second part (2b) via their respective surfaces; - a means of placing the battery housing (1) under vacuum by sucking air via said ventilation valve (3).

2. System according to claim 1 characterized in that the surface of the first part (2a) and the surface of the second part (2b) are flat.

3. System according to claim 1 or 2 characterized in that the first part (2a) of the battery housing (1) comprises the ventilation valve (3).

4. System according to any one of claims 1 to 3, characterized in that the ventilation valve (3) has a diameter of between 1 cm and 5 cm.

5. Closing method implementing a system for assembling a battery case (1) according to any one of claims 1 to 4, characterized in that said method comprises the following steps: - a step of bonding the first part (2a) of the battery case and the second part (2b) of the battery case (1) by distributing an adhesive on their respective surfaces; - a step of sucking air from the battery case (1) by the ventilation valve (3) compressing the first part (2a) onto the second part (2b) of the case (1).

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