DE102011103965A1 - Electrochemical battery for vehicle e.g. electric vehicle, has single cells which are conductively coupled with heat conducting plate to which spacers are connected - Google Patents

Abstract

The electrochemical battery (1) has several single cells (2) that are arranged in a cell case (3). The electrode stacks are arranged in the cell case. A spacer (9) is arranged between single cells for setting the defined distance between pole contacts (5,6) of single cells. The single cells are conductively coupled with a heat conducting plate (7) to which spacers are connected.

Description

The invention relates to an electrochemical battery with a plurality of individual cells, comprising a cell housing and arranged in the cell housing electrochemically active electrode stack, wherein between the individual cells in each case at least one spacer for setting a defined distance between pole contacts of adjacent individual cells is arranged and wherein the individual cells conduct heat with a Heat conducting plate are coupled.

The invention further relates to a use of an electrochemical battery.

Electrochemical high-voltage batteries for vehicle applications are generally known from the prior art, which are formed from a plurality of individual cells electrically connected in parallel and / or in series. The individual cells have a round or angular cross-section. Prismatic single cells are known, which have a cell housing formed from metal or plastic. Due to large areas of the housing, this has a low rigidity, so that it may come due to an electrode coil located in the interior of the housing to buckling and bulging of the housing. The electrode winding is formed from stacked anode and cathode foils which are separated from each other by a separator film. The anode and cathode films as well as the separator film are wound on a flat mandrel. A dependent on loading and aging state of the single cell thickness growth of the electrode coil leads to the change of a thickness of the single cell by the bulging of housing walls. However, an arrangement of a plurality of individual cells in a cell network and a simple electrical contacting of the individual cells by means of cell connectors are only possible if the individual cells are arranged at a defined distance from each other. Spacers, also referred to as spacers, are provided for this purpose, into which the individual cells are inserted. A defined thickness of the spacers results in a uniform pitch of the individual cells in the cell assembly, wherein the thickness change and a thickness tolerance of the single cell are compensated by means of a change in a gap between the housing of the single cell and an inner side of the spacers. The spacer is provided with an elastic element. A length of the cell network remains constant. For discharging a heat loss arising during operation of the individual cells, a direct cooling is known in which a direct flow around the individual cells takes place with a cooling fluid. Further, an indirect cooling is known in which the cooling fluid is guided in a closed heat conducting plate, wherein the individual cells are thermally connected thereto. To increase a heat transfer between the individual cells and the heat conducting plate additional, designed as a cooling plates or cooling rods heat conducting elements are provided, which are in heat-conducting contact with the respective individual cell and the heat conducting. In addition, it is known that the individual cells are pressed by means of clamping elements on the heat conducting plate, wherein the clamping elements comprise frame members, ironing elements and other elements.

An electrochemical battery is out of the DE 10 2005 031 504 A1 known, wherein the battery has a prismatic shape and is formed of a plurality of individual cells. Of the individual cells, at least two are each combined to form a prismatic module and at least two of the modules are stacked to form the battery and braced together between two end plates. The battery further comprises a heat-conducting contact with the modules in heat-conducting contact, wherein the cooling body wenigstes has a cooling fin, which is formed parallel to the direction of force of the tension. For bracing the modules tie rods are provided, the tie rods are formed by the cooling fins.

Furthermore, from the DE 10 2008 016 936 A1 an electrochemical battery with a plurality of flat cells known. The flat cells each comprise an electrolyte, at least two arresters and a housing, wherein the flat cells are stacked with their substantially mutually parallel flat sides stacked. Between two adjacent flat cells at least one cooling plate is arranged parallel to and separated from these, wherein the cooling plate is angled on at least one side.

The invention has for its object to provide a comparison with the prior art improved electrochemical battery and a use of the electrochemical battery.

With regard to the electrochemical battery, the object is achieved by the features specified in claim 1 and in terms of the use of the electrochemical battery by the features specified in claim 10.

Advantageous embodiments of the invention are the subject of the dependent claims.

An electrochemical battery has a plurality of individual cells, each individual cell comprising a cell housing and an electrochemically active electrode stack arranged in the cell housing. Between the individual cells is at least one spacer for setting a defined distance between pole contacts arranged adjacent individual cells and the individual cells are heat conductively coupled to a heat conducting plate. According to the invention, the spacers are each designed as a heat conducting element and heat conductively coupled to the heat conducting plate.

From the design of the spacer elements as Wärmeleitelemente results in an advantageous manner that with little effort, a particularly effective temperature control of the individual cells can be realized, so that they are always operable with optimum efficiency. Furthermore, no additional heat-conducting elements are required, so that the temperature of the individual cells and thus the battery with a particularly low cost of materials and consequently with low cost is feasible. Also, the battery can be made particularly small construction for this reason.

Embodiments of the invention are explained in more detail below with reference to drawings.

Showing:

1 1 is an exploded view of a first embodiment of an electrochemical battery according to the invention;

2 schematically a perspective view of the battery according to 1 .

3 schematically a perspective view of a heat conducting plate of the battery according to 1 .

4 schematically a perspective view of a single cell and a spacer of the battery according to 1 in the unmounted state,

5 schematically a first longitudinal section of the battery according to 1 .

6 schematically a second longitudinal section of the battery according to 1 .

7 schematically a cross section of the battery according to 1 .

8A schematically a single cell, a spacer and a heat conducting plate of a second embodiment of a battery according to the invention in the unassembled state,

8B schematically the single cell, the spacer and the heat conduction according to 8A in the assembled state,

9 FIG. 2 schematically a cross section of a third exemplary embodiment of a battery according to the invention;

10 1 is an exploded view of a fourth embodiment of an electrochemical battery according to the invention;

11 schematically a perspective view of the battery according to 10 .

12 schematically a perspective view of a single cell and two spacers of the battery according to 10 in the unmounted state,

13A 1 is a perspective view of a heat conducting plate with a single cell of a fifth embodiment of a battery according to the invention attached to the heat conducting plate by means of a spacer;

13B schematically a longitudinal section of the heat conducting plate with the attached by means of the spacer to the heat conducting plate according to individual cell 13A .

13C schematically a cross section of the heat conducting plate with the attached by means of the spacer to the heat conducting plate according to single cell 13A and

14 a perspective view of a single cell, two spacers and a fastener of a sixth embodiment of a battery according to the invention in the unassembled state.

Corresponding parts are provided in all figures with the same reference numerals.

The 1 and 2 show a first embodiment of an electrochemical battery according to the invention 1 in different representations. At the battery 1 it is a high-voltage battery for use as energy storage for electrical energy in a vehicle, not shown. The vehicle is in particular an electric vehicle or a hybrid vehicle, by means of which in the battery 1 stored electrical energy an electric drive motor of the vehicle is operable. Alternatively or additionally, the battery 1 a so-called starter battery for starting an internal combustion engine of the vehicle, wherein the vehicle can also have exclusively an internal combustion engine for driving in this case.

The battery 1 includes several electrical interconnected single cells 2 , which in the illustrated embodiment as so-called prismatic single cells 2 are formed. Each of the single cells 2 has a cell case 3 and one in the cell case 3 arranged electrochemically active electrode stack 4 on which in 6 is shown in more detail. The electrode stack 4 is not in illustrated manner formed from stacked anode and cathode foils, which are separated from each other by a Separatorfolie. The anode and cathode films as well as the separator film are wound on a flat mandrel, so that the electrode stack 4 forms an electrode winding. Alternatively, the electrode stack 4 in unwrapped form within the cell housing 3 arranged.

Because the single cells 2 During their operation due to heat losses, these heat are conductive with a heat conducting plate 7 coupled to the heat loss from the single cells 2 evacuate. To improve the heat transfer is between the individual cells 2 and the heat conducting plate 7 a heat-conducting foil 15 arranged. The heat conduction plate 7 has a cooling channel 7.1 on, which can be acted upon with a cooling medium, for example water or a refrigerant of a vehicle air conditioning system.

For electrical coupling, each of the individual cells comprises 2 pole contacts 5 . 6 , where the single cells 2 by means of cell connectors 8th electrically coupled in parallel and / or in series with each other. For this electrical coupling by means of the cell connectors 8th It is necessary for a distance between the pole contacts 5 . 6 adjacent single cells 2 is constantly formed. Since it depends on a state of charge and aging to changes in thickness of the electrode stack 4 come, are spacers 9 provided, which also with changes in thickness of the respective electrode stack 4 a constant distance between the pole contacts of adjacent single cells 2 to ensure.

In the illustrated embodiment, the spacers 9 each have a U-shaped cross-section and surround the respective individual cells 2 cassette-shaped on its side walls and on its upper side. To carry out the pole contacts 5 . 6 through an upper surface of the respective spacer 9 have the spacers 9 to the pole contacts 5 . 6 correspondingly formed recesses A1, A2.

To attach the individual cells 2 on the heat conducting plate 7 and a compression of the individual cells 2 on the heat conducting plate 7 to improve heat transfer between the heat conducting plate 7 and the single cells 2 to enable are the spacers 9 simultaneously formed as clamping elements. These are opposite and perpendicular to the heat conduction 7 extending end faces of the spacers 9 opposite flat sides of the spacers 9 Lug-like extended, so that tab-like extensions 9.1 . 9.2 form. In these extensions 9.1 are recesses A3, A4 introduced, through each of which a screw 10 for non-positive and positive fastening of the spacer 9 on the heat conducting plate 7 is feasible. The recesses A3 are in 4 shown in more detail.

For holding the screws 10 are in longitudinal end faces of the heat conduction plate 7 Holes B1, B2 introduced with an internal thread, not shown, wherein the holes B1 in 3 are shown in more detail.

Furthermore, the spacers 9 designed as a heat conducting element and heat conductive with the heat conducting 7 connected, so that of the single cells 2 Loss of heat generated during their operation particularly efficient to the heat conduction 7 is transferable. For this purpose, the spacers 9 made of a material with a high specific thermal conductivity, in particular of metal. The metal is for example aluminum or copper. Here is the spacer 9 at least in the area of the tab-shaped extensions 9.1 . 9.2 formed from the material with high specific thermal conductivity to a high heat transfer between the heat conduction 7 and the spacer 9 to create.

To make electrical contact between the cell casings 3 and the spacers 9 to avoid is between the individual cells 2 and the respective associated spacers 9 an electrically insulating and thermally conductive material 11 arranged. The electrically insulating and thermally conductive material 11 is in 13B shown in more detail and formed as a heat conducting foil or heat conducting compound. The material 11 has a high specific thermal conductivity and a good plastic and elastic deformability. Due to the good plastic and elastic deformability of the material 11 This serves at the same time to a tolerance compensation of the individual cells 2 already during the assembly of the battery 1 and at thickness changes of the electrode stack 4 as well as the resulting shape changes of the cell housing 3 ,

By the compression of each single cell 2 to the heat conducting plate 7 by means of the spacers 9 the tolerance compensation is achieved, with a lateral deflection of one of the individual cells 2 and the heat conducting plate 7 formed cell composite by a on the thermally conductive material 11 on the single cells 2 exerted pressure force is prevented.

Also the spacers 9 themselves are preferably plastically and / or elastically deformable, wherein the deformability of the spacers 9 takes place exclusively in areas which are not the distance between the pole contacts 5 . 6 influence.

To further improve the heat transfer between the spacers 9 and the heat conducting plate 7 are in the spacers 9 integrated Wärmeleitanordnungen not shown, wherein the Wärmeleitanordnungen cooling plates, cooling rods and / or heat pipes are.

In embodiments not shown, not every single cell is 2 with the heat conducting plate 7 pressed. For example, every second or every third cell is single 2 by means of a spacer 9 with the heat conducting plate 7 pressed.

In further embodiments, not shown, the spacers 9 to a fixation of the individual cells 2 on a carrier device, for example a plate, a profile or another carrier device, provided in order to produce a mechanically stable cell assembly. The carrier device can serve exclusively the mechanical fixation. In addition, the carrier device can also have a cooling function.

For fixation of single cells 2 in the longitudinal direction of the battery 1 At the end of each is a so-called pressure goggles 12 arranged and the single cells 2 are together with the pressure goggles 12 by means of tension bands 13 braced. The pressure goggles 12 each have to the straps 13 correspondingly formed recesses V1, V2, which fixation of the clamping bands in a predetermined vertical position of the battery 1 enable.

3 shows the heat conduction plate 7 in a detail with the cooling channel 7.1 and the holes B1, B2. The heat conduction plate 7 puts a heat sink inside the battery 1 is to which the individual cells are thermally coupled to dissipate the power loss.

In 4 is a perspective view of a single cell 2 and a spacer 9 shown in disassembled state for detailed illustration, wherein the spacer 9 the recesses A1, A2 for carrying out the pole contacts 5 . 6 and the recesses A3, A4 for passing the screws 10 having.

The 5 and 6 show longitudinal sections of the battery 1 in a plan view, wherein in 5 the single cells 2 are not shown. Regardless of a thickness of the single cells 2 is by means of each spacer 9 given a constant grid R, so that always a defined distance between the pole contacts 5 . 6 adjacent single cells 2 is available. Thus, the electrical connection of the individual cells 2 by means of connection of the pole contacts 5 . 6 based on the cell connectors 8th even with changes in thickness of the electrode stack 4 and consequent deformations of the cell case 4 possible.

In 7 is a cross section of the battery 1 represented by which the arrangement and the attachment of the individual cells 2 and the spacer 9 on the heat conducting plate 7 be clarified.

The 8A and 8B show a single cell 2 a spacer 9 and a heat conduction plate 7 a second embodiment of the battery 1 in unassembled and assembled condition.

Unlike in the 1 to 7 illustrated first embodiment of the battery 1 is the spacer 9 for fastening and clamping on the heat conducting plate 7 in the area of the tab-like extensions 9.1 . 9.2 the front sides reshaped. The extensions 9.1 . 9.2 each in one in a bottom of the heat conduction 7 introduced recess V3, V4 a form-fitting. For a simple and optimized reshaping of the extensions 9.1 . 9.2 To realize, edges are at the bottom of the heat conduction plate 7 rounded off.

In 9 is a third embodiment of the battery according to the invention 1 shown in a cross section. Unlike the in 8th shown second embodiment is additionally between an upper side of the respective single cell 2 and the spacer 9 a spring element 14 arranged, which is formed in the illustrated embodiment as a spiral spring. Alternatively, training as a leaf spring, flexible mat, especially foam mat, possible.

The spring element 14 is to compensate for tolerances, thermal expansion, setting losses and other operational position and shape changes of the single cell 2 provided in the vertical direction and presses the single cell 2 defined on the heat conducting plate 7 ,

A use of the spring element 14 is in addition in all others in the 1 to 8th as well as the 10 to 14 illustrated embodiments of the battery 1 possible.

The 10 and 11 show a fourth embodiment of the electrochemical battery according to the invention 1 in different representations.

Unlike in the 1 to 7 illustrated first embodiment of the battery 1 are the spacers 9 not cassette-shaped, but have a T-shaped cross-section. A spacer 9 is in each case between two individual cells 2 arranged so that a single cell 2 of two spacers 9 enclosed in a cassette.

To carry out the pole contacts 5 . 6 of the single cells 2 are in the spacers 9 each four recesses A1, A2, A5, A6 formed. The recesses A1, A2, A5, A6 have a semicircular cross section, so that the recesses A1, A2, A5, A6 of two adjacently arranged spacers 9 give an overall recess with a round cross-section.

The attachment of the spacers 9 on the heat conducting plate 7 again by means of the screws 10 ,

For the enclosure of the cell composite end limiting single cells 2 are end plates 16 provided, which on one to the pressure goggles 12 aligned side flat and on the opposite side to the half-recording of each individual cell 2 are formed. The end plates 16 also have tab-like extensions at their ends 16.1 . 16.2 and on its upper side semicircular recesses A7, A8 for carrying out the pole contacts 5 . 6 on.

12 shows a single cell 2 and two spacers 9 in the unmounted state in a detailed view.

In the 13A to 13C is in different views a heat conduction plate 7 with one by means of a spacer 9 on the heat conducting plate 7 attached single cell 2 a fifth embodiment of the battery according to the invention 1 shown.

In addition to that in the 10 to 12 illustrated fourth embodiment is between flat sides of the single cell 2 and the spacer 9 the thermally conductive material 11 arranged, which is formed in the illustrated embodiment as a heat conducting foil, but alternatively can also be introduced as a thermally conductive mass.

Due to the thermally conductive material 11 is the heat transfer between the spacer 9 and the single cell 2 improved, so that a large amount of the heat loss of the single cell 2 to the spacer 9 is delivered. At the same time serves the thermally conductive material 11 to compensate for tolerances of the single cell 2 and for electrical isolation between the single cell 2 and the spacer 9 , The of the spacer 9 absorbed heat is in the direction of the heat conduction 7 passed, where it comes to this for heat exchange. Due to the compression of the tab-like extensions 9.1 . 9.2 on the heat plate 7 by means of screws 10 a high heat transfer is achieved.

Also in the embodiments of the battery 1 in which the attachment of the spacers 9 on the heat conducting plate 7 by forming the tab-like extensions 9.1 . 9.2 into the recesses V3, V4 of the heat conducting plate 7 takes place, is preferably the thermally conductive material 11 between the individual cells 2 and the spacers 9 introduced to increase the heat transfer.

14 shows a perspective view of a single cell 2 , two spacers 9 and a fastener 17 a sixth embodiment of the battery according to the invention 1 in unassembled condition.

The fastener 17 is a cohesive connection of the individual cells 2 with the respective spacers 9 provided and formed in the illustrated embodiment as a double-sided adhesive element. Due to the use of the fastener 16 become the single cells 2 by means of the spacers not only positive and positive fit to the heat conduction 7 but are pressed in the spacers 9 additionally fixed cohesively. This leads in particular to the advantage that even with non-constant thickness dimensions of the individual cells 2 in the longitudinal direction of the cell composite, a play-free concern of the individual cells 2 inside the spacers 9 is ensured.

In a particularly advantageous development, the fastening element forms 17 at the same time the thermally conductive material 11 ,

LIST OF REFERENCE NUMBERS

1

battery

2

single cell

3

tent housing

4

electrode stack

5

pole contact

6

pole contact

7

heat conduction

7.1

cooling channel

8th

cell connectors

9

spacer

9.1

renewal

9.2

renewal

10

screw

11

material

12

pressure glasses

13

strap

14

spring element

15

Heat conducting

16

endplate

16.1

renewal

16.2

renewal

17

fastener

A1 to A8

recess

B1, B2

drilling

R

Pitch

V1 to V4

deepening

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102005031504 A1 [0004]
• DE 102008016936 A1 [0005]

Claims (10)

Electrochemical battery ( 1 ) with several single cells ( 2 ) comprising a cell housing ( 3 ) and one in the cell housing ( 3 ) arranged electrochemically active electrode stack ( 4 ), whereby between the single cells ( 2 ) at least one spacer ( 9 ) for setting a defined distance between pole contacts ( 5 . 6 ) of adjacent single cells ( 2 ) and wherein the individual cells ( 2 ) Heat conducting with a heat conducting plate ( 7 ), characterized in that the spacers ( 9 ) are each formed as a heat conducting element and conducting heat with the heat conducting plate ( 7 ) are coupled. Electrochemical battery ( 1 ) according to claim 1, characterized in that the individual cells ( 2 ) by means of clamping elements with the heat conducting plate ( 7 ) are pressed, the clamping elements by the spacers ( 9 ) are formed. Electrochemical battery ( 1 ) according to claim 1 or 2, characterized in that the spacers ( 9 ) are plastically and / or elastically deformable. Electrochemical battery ( 1 ) according to one of the preceding claims, characterized in that in the spacers ( 9 ) Wärmeleitanordnungen are integrated. Electrochemical battery ( 1 ) according to claim 4, characterized in that the Wärmeleitanordnungen are cooling plates, cooling rods and / or heat pipes. Electrochemical battery ( 1 ) according to one of the preceding claims, characterized in that the spacers ( 9 ) force, substance and / or form-fitting with the individual cells ( 2 ) and / or the heat conducting plate ( 7 ) are connected. Electrochemical battery ( 1 ) according to one of the preceding claims, characterized in that between the individual cells ( 2 ) and the at least one contacting spacer ( 9 ) an electrically insulating and / or thermally conductive material ( 11 ) is arranged. Electrochemical battery ( 1 ) according to one of the preceding claims, characterized in that the individual cells ( 2 ) cohesively with the at least one standing in contact spacer ( 9 ) are connected. Electrochemical battery ( 1 ) according to one of the preceding claims, characterized in that between the individual cells ( 2 ) and the at least one contacting spacer ( 9 ) at least one spring element ( 14 ) is arranged. Use of an electrochemical battery ( 1 ) according to one of the preceding claims for a vehicle, wherein the vehicle is an electric vehicle or a hybrid vehicle.

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