FR3144706A1 - Power connection support device for a battery, in particular for an electric vehicle battery - Google Patents

Abstract

Power connection support device for a battery, in particular for an electric vehicle battery The present invention relates to a power connection support device for a battery, in particular for an electric vehicle battery, said device comprising a support (1) having an external surface (1a), at least one component (2a, 2b, 2c ) fixed on the external surface of the support (1), one or more conductors (3a, 3b) of low impedance to which are connected and fixed at separate connection and fixing points at least the component(s), connecting elements (4a , 4b) each inserting into the external surface of the support (1), or into the or one of the component(s) fixed on the external surface of the support (1). It is characterized in that at least one of the connecting elements is crossed by a channel comprising two fluid inlet and outlet openings (401a, 401b) and in that it further comprises a circuit cooling system (5) comprising a pipe, in which a cooling fluid can circulate, extending in and/or outside the support up to the or each hollow connecting element so as to put its opening in fluid communication fluid inlet with the pipeline. Figure to be published with the abstract: Fig. 2

Description

Power connection support device for battery, especially for electric vehicle battery

The present invention relates to the field of batteries, in particular for electric vehicles with battery and has as its subject a power connection support device for battery, in particular for electric vehicle battery.

It is known that batteries for electric vehicles are used to store energy to provide an energy source for driving the vehicle, such as a battery electric vehicle (BEV) using exclusively an electric motor for its propulsion or a hybrid electric vehicle (HEV) having a thermal engine coupled to at least one electric motor whose power supply is provided by the battery kept charged by the thermal engine.

The batteries used in these vehicles generally comprise one or more electrochemical battery cell modules, each forming a single energy accumulator, for example a lithium-ion accumulator. They further comprise a support, generally forming part of the battery housing, on which components (power relay, switch or fuse for example) are mounted, connected together by low impedance conductors such as bus bars (or bus bars), or conductive wires. These components are connected, on the one hand, to the battery cells by a power input via one of the conductors and, on the other hand, to the vehicle's traction system by a power output via another conductor.

The connection for maintaining the conductors connected and assembled to the components, possibly by fixing them to the support, is generally carried out by means of screws, each forming a connection and fixing point, which are screwed into the support or into a component fixed to the support. More particularly, each screw is inserted into a tapping made or reported in a hole made in the surface of the support or in the component.

However, with the increasing development of electric vehicles, the power required and the load continue to increase, which generates an increase in the temperature of the components (generally called power components) resulting, due to thermal conduction, in hot spots, in particular at the connection and fixing points of the conductors which are in contact, by thermal conduction, with the components. This heating problem arises in particular in phases of high current demand and the components can reach their operating limit due to this increase in temperature.

A solution to this problem could be to cool the entire support, but this solution would not be sufficient or technically optimal. Another solution is the use of bus bars, for example in the form of plates or flat bars, which, in addition to their function of conducting and distributing the electric current, have a larger contact surface with the surrounding air than conductors such as conductive wires, for example. Such a contact surface limits the temperature rise and promotes the cooling of the fixing and connection points and therefore of the components, but this solution is clearly insufficient.

The present invention aims to overcome these drawbacks.

For this purpose, the power connection support device, according to the present invention, for a battery, in particular for an electric vehicle battery, said device comprising a support having an external surface, at least one component fixed to the external surface of the support, one or more low-impedance conductors to which at least the component(s) is or are connected and fixed at separate connection and fixing points, connecting elements each inserted into the external surface of the support, or into the or one of the component(s) fixed to the external surface of the support, forming one of the connection and fixing points, is characterized in that at least one of the connecting elements, called a hollow connecting element, is crossed by a channel comprising a fluid inlet opening and a fluid outlet opening and in that it further comprises a cooling circuit comprising a pipe in which a cooling fluid can circulate or circulates, said pipe extending into and/or outside the support. to the or each hollow connecting element so as to place its fluid inlet opening in fluid communication with the pipeline, each connection and fixing point formed by a hollow connecting element thus further forming a cooling point.

Such a solution allows for local action, i.e. at the connection points between components and conductors where temperatures are highest, and provides sufficient active cooling of the components so that they cannot reach their operating limit.

The invention will be better understood from the following description, which relates to a preferred embodiment, given as a non-limiting example, and explained with reference to the attached schematic drawings, in which:

is a partial perspective view of a support device according to the present invention,

shows the support device shown in the with the cooling fluid supply unit of the cooling circuit,

is a partial and exploded view of the support device shown in the ,

is another partial and exploded view of the support device shown in the ,

is another partial and exploded view of the support device shown in the ,

is another partial and exploded view of the support device shown in the ,

is a sectional view of the support device shown in the , at the level of two hollow connecting elements inserted into the support in fluid communication with the internal pipeline,

is a sectional view of the support device shown in the , at the level of a hollow connecting element inserted into one of the components and communicating fluidically with the external pipeline,

is a perspective view of a hollow connecting element in a preferred embodiment,

is a longitudinal sectional view of the hollow connecting element shown in the .

The attached figures show, at least partially for some of them, a power connection support device, according to the present invention for a battery, in particular for an electric vehicle battery, more particularly intended to be connected to the traction system of a vehicle, said device comprising:

- a support 1 having an external surface 1a,

- at least one component 2a, 2b, 2c fixed on the external surface of the support 1,

- one or more low impedance conductors 3a, 3b to which at least the component(s) 2a, 2b, 2c is or are connected and fixed at separate connection and fixing points,

- connecting elements 4a, 4b each inserted into the external surface of the support 1, or into the component(s) 2a, 2b, 2c fixed to the external surface 1a of the support 1, forming (each) one of the connection and fixing points.

By: inserting into the external surface of the support 1 is meant an insertion or penetration of the connecting element 1 into the external surface 1a inside or into the thickness of the support 1 to a depth appropriate for achieving the fixing.

The conductor(s) 3a, 3b may consist of any type of low impedance conductor such as, for example, bus bars, flat or round, or conductive wires. Shapes of conductors 3a, 3b allowing losses to be dissipated effectively thanks to a good ratio between their dissipative surface and their conductive surface are favored by the present invention.

The components 2a, 2b, 2c can be connected, on the one hand, to the cells of the battery (not shown in the attached figures) by a power input via one of the conductors 3a, called the power input conductor and, on the other hand, to the traction system of the vehicle (not shown in the attached figures) for example by a power output via another conductor 3a, called the power output conductor.

Two components 2a, 2b or 2b, 2c can be electrically connected to each other by the conductor(s) 3b (figures 1, 2, 5, 6).

In a particular form, the conductors 3a, 3b can be aligned in the same plane (figures 1, 2, 5, 6). The two power input and output conductors 3a can then be located respectively at the ends of the alignment on the support 1.

According to the present invention, in such a support device, at least one of the connecting elements 4a, 4b, called hollow connecting element 4a, 4b, is crossed by a channel 40a, 40b comprising a fluid inlet opening 400a, 400b and a fluid outlet opening 401a, 401b.

Still in accordance with the present invention, such a device further comprises a cooling circuit 5 comprising a pipe 5a, 5b in which a cooling fluid can circulate or circulates, said pipe 5a, 5b extending into and/or outside the support 1 to the or each hollow connecting element 4a, 4b so as to put its fluid inlet opening 400a, 400b into fluid communication with the pipe 5a, 5b. Each connection and fixing point formed by a hollow connecting element 4a, 4b thus further forms a cooling point. It is understood that the cooling liquid passes through the or each hollow connecting element 4a, 4b by circulating in its channel 40a, 40b.

Such a solution makes it possible to act locally at the level of the connecting elements 4a, 4b and therefore at the level of the hot spots where the temperature is high, or even the highest, that is to say at the level of the connection points between the components 2a, 2b, 2c and the conductors 3a, 3b, which makes it possible to obtain sufficient active cooling of the components, possibly adding to an effective dissipation of losses thanks to a good ratio between the dissipating surface and the conducting surface of the conductors 3a, 3b when they are chosen with an appropriate shape as seen previously, so that the components 2a, 2b, 2c cannot reach their operating limit. Another advantage is to be able to use conductors such as conductive wires which have a low cooling power (small contact surface with the surrounding air), unlike bus bars or other conductors, for example in the form of a plate or flat bar, which have a higher cooling/dissipation power.

Preferably, with particular reference to FIGS. 7 to 10, it can be seen that the or each hollow connecting element 4a, 4b may be a hollow fixing screw. Such a hollow fixing screw may comprise a hollow threaded rod 41a, 41b, preferably comprising the fluid inlet opening 400a, 400b, and a head 42a, 42b, preferably comprising the fluid outlet opening 401a, 401b. The rod 41a, 41b may then be inserted into the external surface of the support 1 ( for example) or in the or one of the components 2a, 2b, 2c fixed on the external surface 1a of the support 1 ( for example). Thus, the rod 41a, 41b may comprise at least one perforation, for example axial (in the axis of the rod) or radial (perpendicular to the axis of the rod), forming the inlet opening 400a, 400b opening into the hollow part forming the channel 40a, 40b and a perforation, for example axial, forming the fluid outlet opening 401a, 401b, opening into the channel 40a, 40b and which may be made, preferably, in the head 42a, 42b.

The present invention may provide at least one fixing sleeve 7, preferably threaded, inserted into the external surface 1 of the support 1 by extending into the latter so as to open into the pipe 1 or into the or one of the components 2a, 2b, 2c. The or each hollow connecting element 4a, 4b inserted into the external surface of the support 1 or into the or one of the components can then be inserted into the or one of the fixing sleeve(s) 7. The fixing sleeves 7 make it possible to obtain a better tightening torque of the or each hollow fixing screw 4a, 4b.

The or each component 2a, 2b, 2c may be fixed to the external surface 1a of the support 1 by one or more screws or by other fixing means such as gluing.

More particularly, the or each hollow fixing screw 4a can be inserted into the surface 1a of the support 1 by passing through the corresponding conductor 3a, 3b which has a hole 30a, 30b for this purpose, said conductor 3a, 3b being pressed against the external surface 1a between the latter and the head 42a, 42b of the corresponding hollow fixing screw 4a, 4b, which ensures that the conductor is held in the connection position on the support 1 (see in particular the ). Similarly, as can be seen more particularly on the , the or each hollow fixing screw 4b can be inserted into the or one of the components 2b by passing through the conductor 3a, 3b. More particularly, each hollow fixing screw 4a, 4b also passes through a contact part (in the form of a tab or plate for example) of the component 2a, 2b, 2c establishing the electrical contact between the latter and the conductor 3a, 3b. The conductor 3a, 3b and the contact part of the component 2a, 2b, 2c are then pressed by the head 42a, 42b of the hollow fixing screw 4a, 4b against the external surface 20b of the component 2b.

Preferably, to locally increase the effect/power/of the cooling (or heat dissipation), the channel 40a, 40b of the or at least one of the hollow connecting element(s) 4a, 4b may be delimited by an internal wall provided with a thermal system 6, for example of the fin type, making it possible to increase the contact surface with the cooling fluid in order to increase the conductive exchanges (figures 9 and 10). These fins 6 can be provided for the connecting elements 4a inserted into the external surface 1a of the support 1 or for the connecting elements 4b inserted into the or one of the components 2a, 2b, 2c fixed on the support 1. FIGS. 9 and 10 show a hollow fixing screw 4b comprising such fins 6 and which is more particularly provided to be inserted into the or one of the component(s) 2a, 2b, 2c as we will see later thanks to a lateral opening 400b forming the fluid inlet opening 400b, but it could also be used to be inserted into the external surface 1a of the support 1. It is therefore understood that the same arrangement of the fins 6 can be envisaged in another type of hollow fixing screw, that is to say a hollow fixing screw not comprising a lateral opening 400b or not requiring, this which is the case of the hollow fixing screws 4a intended to be inserted into the external surface 1a of the support 1, such a lateral opening 400b ( ).

In a preferred embodiment, referring in particular to FIGS. 3 and 7, it can be seen that at least part of the pipe, called the internal pipe 5a, extends into the support 1. The support 1 may comprise an internal cavity forming or receiving said internal pipe 5a (which is then, in the latter case, added to the support 1). The fluid inlet opening 400a of the or each hollow connecting element 4a, called the first hollow connecting element 4a, inserted into the external surface 1a of the support 1, may open into the internal pipe 5a. In this case, the axes X1, X2 respectively of the fluid inlet 400a and outlet 401a openings of the or each first connecting element 4a may be substantially aligned on the same axis, where appropriate on the axis of the threaded rod 41a ( ).

In this same preferred embodiment or in another embodiment not comprising an internal pipe 5a, the pipe may comprise at least one part of the pipe, called the external pipe 5b, extending outside the support 1 (see in particular FIGS. 1, 2, 6 and 8). In addition, the fluid inlet opening 400b of the or each hollow connecting element 4b, called the second hollow connecting element 4a, inserted into the or one of the components 2b, may open into the external pipe 5b.

It is therefore understood that the present invention can provide, depending on the type of configuration, an internal pipe 5a and/or an external pipe 5b. The attached figures illustrate a preferred embodiment of the device comprising both an internal pipe 5a and an external pipe 5b.

In a preferred embodiment of the external pipe 5b, as can be seen in FIGS. 1, 2, 5, 6, 8, the latter may comprise at least one conduit 50b and connectors 51b, 52b, namely at least one first connector 51b and at least one second connector 52b, making it possible to connect the or each conduit 50b, using the first connector 51b, to the internal pipe 5a for its supply of fluid by the latter or to another supply of fluid and, using the second connector 52b, to the fluid inlet opening 400b of the or one of the second hollow connecting element(s) 4b. The present invention may also provide clamps 53b making it possible to maintain, or reinforce the maintenance, of the conduits 50b and the connectors 51b, 52b together ( ).

In the case of the external pipe 5b, the axis X1 of the fluid inlet opening 400b and the axis X2 of the fluid outlet opening 401b of the or each second hollow connecting element 4b are oriented perpendicularly to each other (see in particular FIGS. 8 and 10). As can be seen more particularly in FIGS. 8, 9 and 10, the axis X1 of the fluid inlet opening 400b of the or each second hollow connecting element 4b is perpendicular to the axis of the threaded rod 41b and the fluid outlet opening 401b is made axially in the head 42b. This feature allows the fluid to arrive from the outside in the channel 40b of the connecting element 4b since the hole made in the component 2b to receive the latter is blind and it cannot therefore be put in fluid communication with the internal pipe 5a ( notably).

In a preferred embodiment of the second connector 52b, the latter may comprise a body 520b and a lateral extension 521b. The body 520b comprises an axial or central perforation 522b and a lateral perforation 523b. The lateral extension 521b is crossed by an internal cavity in communication with the lateral perforation 523b opening into the axial or central perforation 522b. The lateral extension 521b is connected to the conduit 50b such that its internal cavity opens into the latter to ensure their fluid communication. The corresponding hollow fixing screw 4b is inserted into the axial perforation 522b so that its fluid inlet opening 400b opens into the lateral perforation 523b in order to put the internal cavity of the lateral extension 521b, and therefore the conduit 50b, and the channel 40b of the hollow fixing screw 4b into fluid communication (see in particular the .

The assembly formed by such a second fitting 52b and such a hollow fixing screw 4b with two openings 400b, 401b oriented perpendicularly to each other (see above), is generally known as a “banjo” fitting or screw.

The coolant may be in the form of a gas or gas mixture, for example air, or in a liquid form, for example water.

In one embodiment using a cooling fluid in the form of a gas or gas mixture, for example air, the cooling circuit 5 may be configured so that said cooling fluid passes through the or each hollow connecting element 4a, 4b, escaping (freely) through its fluid outlet opening 401a, 401b directly into the surrounding atmosphere of the support 1 (see in particular FIG. ). In this case, the cooling circuit 5 may comprise a cooling fluid supply unit comprising a compressor 5c or a pulsed air system making it possible to supply, for example via a connector 5d, the pipe 5a, 5b with air (in the direction of circulation of the fluid F illustrated in the ) at an entry point E in the pipeline 5a, 5b (see in particular figures 2, 3, 4, 6).

In another embodiment (not shown in the attached figures) using a cooling fluid in liquid form, the cooling circuit 5 can form a closed circuit comprising a fluid return loop 5c connected to the outlet opening 401a, 401b of the or each hollow connecting element 4a, 4b so that said cooling fluid passing through the or each hollow connecting element 4a, 4b escapes from the latter into said fluid return loop 5c. In this case, the cooling circuit 5 can comprise a coolant supply unit comprising, in particular, a coolant reservoir, an exchanger and a pump.

Preferably, the cooling circuit 5, which comprises a cooling fluid (gaseous or liquid) supply unit 5c, may further comprise a control unit and at least one flow adjustment valve controlled by the control unit so as to be able to adjust the fluid flow in the pipe 5a, 5b.

The power supply and/or control unit may be specific/dedicated to the support device or be part of an external cooling circuit, for example the cooling circuit, for example by air or other gaseous or liquid fluid, of the battery.

If we now refer to the , it can be seen that, in the mounted state of the device, the support 1 can be mounted on a part of a battery housing/casing, for example forming the floor or the cover 8 of the housing/casing.

Such a device according to the present invention can thus have the following advantages:

- discrete, individual, targeted cooling of hot spots of a power connection support of a traction battery,

– where applicable, the possibility of carrying out controlled cooling (on demand) by controlling the cooling circuit (by solenoid valve),

- the ability to connect to and take over an external battery cooling circuit or to be specific/dedicated to the device itself,

– does not necessarily require specific sealing because the cooling circuit preferably operates with low pressure,

– small footprint and reduced weight.

Of course, such a device can be used in applications other than electric vehicles, for example for fixed electrical devices.

Of course, the invention is not limited to the embodiment described and shown in the attached drawings. Modifications remain possible, in particular from the point of view of the constitution of the various elements or by substitution of technical equivalents, without departing from the scope of protection of the invention.

Claims (13)

Power connection support device for a battery, in particular for an electric vehicle battery, said device comprising a support (1) having an external surface (1a), at least one component (2a, 2b, 2c) fixed to the external surface of the support (1), one or more low-impedance conductors (3a, 3b) to which at least the component(s) (2a, 2b, 2c) is or are connected and fixed at separate connection and fixing points, connecting elements (4a, 4b) each inserted into the external surface of the support (1), or into the or one of the component(s) (2a, 2b, 2c) fixed to the external surface (1a) of the support (1), forming one of the connection and fixing points, characterized in that at least one of the connecting elements (4a, 4b), called connecting element (4a, 4b) hollow, is crossed by a channel (40a, 40b) comprising a fluid inlet opening (400a, 400b) and a fluid outlet opening (401a, 401b) and in that it further comprises a cooling circuit (5) comprising a pipe (5a, 5b) in which a cooling fluid can circulate or circulates, said pipe (5a, 5b) extending into and/or outside the support (1) to the or each hollow connecting element (4a, 4b) so as to put its fluid inlet opening (400a, 400b) into fluid communication with the pipe (5a, 5b), each connection and fixing point formed by a hollow connecting element (4a, 4b) thus further forming a cooling point. Support device according to claim 1, characterized in that the or each hollow connecting element (4a, 4b) is a hollow fixing screw comprising a hollow threaded rod (41a, 41b), preferably comprising the fluid inlet opening (400a, 400b), and a head (42a, 42b), preferably comprising the fluid outlet opening (401a, 401b), and in that said rod (41a, 41b) is inserted into the external surface of the support (1) or into the or one of the components (2a, 2b, 2c) fixed on the external surface (1a) of the support (1). Support device according to claim 1 or 2, characterized in that the channel (40a, 40b) of the or at least one of the hollow connecting element(s) (4a, 4b) is delimited by an internal wall provided with a thermal system (6), for example of the fin type, making it possible to increase the contact surface with the cooling fluid in order to increase conductive exchanges. Support device according to any one of claims 1 to 3, characterized in that at least part of the pipe, called the internal pipe (5a), extends into the support (1), said support (1) comprising an internal cavity forming or receiving said internal pipe (5a) and in that the fluid inlet opening (400a) of the or each hollow connecting element (4a), called the first hollow connecting element (4a), inserted into the external surface (1a) of the support (1), opens into the internal pipe (5a). Support device according to claim 4, characterized in that the axes (X1, X2) respectively of the fluid inlet (400a) and outlet (401a) openings of the or each first connecting element (4a) are substantially aligned on the same axis (X), where appropriate on the axis of the threaded rod (41a). Support device according to any one of claims 1 to 5, characterized in that the pipe comprises at least one pipe part, called external pipe (5b), extending outside the support (1) and in that the fluid inlet opening (400b) of the or each hollow connecting element (4b), called second hollow connecting element (4a), inserted into the or one of the component(s) (2b), opens into the external pipe (5b). Support device according to claim 6, characterized in that the external pipe (5b) comprises at least one conduit (50b) and connectors (51b, 52b), namely at least one first connector (51b) and at least one second connector (52b), making it possible to connect the or each conduit (50b), using the first connector (51b), to the internal pipe (5a) for its fluid supply by the latter, or to another fluid supply, and, using the second connector (52b), to the fluid inlet opening (400b) of the or one of the second hollow connecting element(s) (4b). Support device according to any one of claims 6 to 7, characterized in that the axis (X1) of the fluid inlet opening (400b) and the axis (X2) of the fluid outlet opening (401b) of the or each second hollow connecting element (4b) are oriented perpendicularly to each other. Support device according to claim 8 and claim 2, characterized in that the axis (X1) of the fluid inlet opening (400b) of the or each second hollow connecting element (4b) is perpendicular to the axis of the threaded rod (41b) and the fluid outlet opening (401b) is made axially in the head (42b). Support device according to any one of claims 1 to 9, characterized in that the cooling fluid is a gas or gas mixture, for example air, and in that the cooling circuit (5) is configured so that said cooling fluid passes through the or each hollow connecting element (4a, 4b) and escapes through its fluid outlet opening (401a, 401b) directly into the surrounding atmosphere of the support (1). Support device according to any one of claims 1 to 10, characterized in that the cooling fluid is in liquid form and in that the cooling circuit (5) forms a closed circuit comprising a fluid return loop (5c) connected to the outlet opening (401a, 401b) of the or each hollow connecting element (4a, 4b) so that said cooling fluid passing through the or each hollow connecting element (4a, 4b) escapes from the latter into said fluid return loop (5c). Support device according to any one of claims 1 to 11 taken each in combination with claim 2, characterized in that it comprises at least one fixing sleeve (7), preferably threaded, inserted into the external surface (1) of the support (1) extending into the latter so as to open into the pipe (1) or into the or one of the component(s) (2a, 2b, 2c) and in that the or each hollow connecting element (4a, 4b) inserted into the external surface of the support (1) or into the or one of the component(s) is inserted into the or one of the fixing sleeve(s) (7). Support device according to any one of claims 1 to 12, characterized in that the cooling circuit (5) comprises a cooling fluid supply unit (5c), a control unit and at least one flow adjustment valve controlled by the control unit so as to be able to adjust the fluid flow in the pipe (5a, 5b).