DE102011016024A1 - Stack i.e. fuel cell stack, for conditioning hydrogen cells in electric drive of e.g. passenger car, has form-closure element fastened at stack independent another form-closure element to hold stack-bodies together in stack - Google Patents

Abstract

The stack (1) has two retaining units (5, 6) for retaining respective form-closure elements (9, 10) that are respectively arranged at ends (E1, E2) of a tension-band device (7) i.e. metal-strip. The stack is formed as a ceramic assembly by stacking plate-shaped stack-bodies (2) i.e. ceramic components, into stacking direction (R). One of the form-closure elements is fastened at the stack independent of the other form-closure element in order to tension the band-device at an outer side (A) of the stack into the stacking direction and to hold the stack-bodies together in the stack. The form-closure elements are designed as a threaded rod and an anchor device. The retaining units are designed as a hole and a recess.

Description

The invention relates to a stack which is formed by stacking at least two stacked bodies in a stacking direction. The stack has a first and a second receiving device for receiving a positive locking element. The stack includes a tension band means adapted to be tensioned on an outside of the stack in the stacking direction and to hold the stack bodies together in the stack. The at least one tensioning band device has a first and a second end, wherein a first positive locking element is arranged at the first end and a second positive locking element is arranged at the second end.

Fuel cell systems are increasingly being used in vehicles, especially in cars or trucks for their electric drive with the progress of development. It is known, a fuel cell stack with a variety of fuel cells by fastening systems, which z. As clamping bands or mounting rails comprise, hold together and / or compress to ensure a sealing effect of arranged between the fuel cell seals or maintain, to ensure safe operation of the fuel cell.

For example, the document describes DE 10 2008 040 251 A1 a fuel cell stack having a plurality of fuel cells and having upper and lower end plates at both ends of the fuel cell stack. The upper and lower end plates have at a lateral and upper part of a recess into which a holding rail is inserted in a stacking direction of the fuel cell. The holding rail touches or engages around the upper and lower end plate at the lateral and upper part. Through an opening in the mounting rail, a retaining block can be inserted into the recesses on the lateral part in a form-fitting manner. The retaining rail and the retaining block are locked by a retaining pin with the end plate. Thus, the mounting rail is flush with the upper and lower end plates, thereby holding the fuel cells in the fuel cell stack together.

Probably the closest prior art forming document DE 10 2004 027 694 A describes a fuel cell stack with clamping system. The fuel cell stack has on its top and bottom in each case an end plate, on whose free side disc springs are arranged. On the disc springs U-steels are arranged, which have at both ends of the U-steels holes with internal thread. Tension rods engage an external thread in the holes to hold two opposing U-steels together and press against the two end plates. The document also describes a fuel cell stack with the two end plates held together by straps. The tension bands extend in the stacking direction of the fuel cell stack, wherein hiss the tension bands and the end plate at least one leaf spring is arranged. The tension straps have first and second ends which are inserted in a tensioning means for tensioning the tension straps. The clamping device is held together by a threaded rod and adjustable in terms of clamping force.

The invention has for its object to provide a stack that can be safely, quickly and compactly held together. This object is solved by the subject matter of claim 1. Preferred or advantageous embodiments of the invention will become apparent from the dependent claims, the following description and / or the accompanying figures.

The invention relates to a stack formed by stacking at least two stacked bodies in a stacking direction. For example, the stacking direction is vertical to a substrate, in particular from the ground upwards. Optionally, the stack is stacked along the ground, that is, in a horizontal direction.

Preferably, the stacking body are formed cuboid or plate-like, with their height is significantly less than their width and / or length. The area formed by the length and the height of the stacked body will hereinafter be referred to as the side surface of the stacked body. Optionally, within the scope of the invention, a side surface which is formed by the width and the height of the stacked body could certainly also be taken into account. In particular, the side surface described below can be seen in a side view of the stack as a longitudinal side aligned parallel to the stacking direction.

A surface formed by the width and length of the stacked body, which is directed to another stacked body or is stacked on this, is referred to below as a stacking surface. The stacked body may also have a freeform, such. B. a round or oval lateral boundary, the terms of the stacking surface and the side surface are analogous to use.

The stack preferably has a first end and a second end, wherein at the first and at the second end of the stack in each case a stacked body is arranged with an open space, which is not followed by another stacked body. These stacking bodies are hereinafter referred to as the first and second end body or first and referred to the second end plate. Preferred within the scope of the invention is that one, optionally also both end body / end plates have a greater width and / or length than the other stacked bodies stacked between the end bodies / end plates and thereby project them vertically from the stack to the stacking direction.

The stack comprises a first and a second receiving device for receiving a positive-locking element. Optionally, the first and / or second receiving device is integrated in one or more of the stacked bodies. Preferably, the first receiving means are arranged on or in the region of the first end body / the first end plate and the second receiving means on or in the region of the second end body / the second end plate.

The stack comprises at least one tension band device, which is designed to be tensioned on an outer side of the stack in the stacking direction. By the tensioning band means the stacked bodies are held together in the stack and / or pressed together. For example, one, two or more Spannbandeinrichtungen can be arranged on one or the outside of the stack. Preferably, the tension band means are / are arranged on two opposite outer sides of the stack in order to ensure a secure cohesion of the stack bodies and to compress them from two sides.

The at least one tensioning band device has a first and a second end, wherein a first positive locking element is arranged at the first end and a second positive locking element is arranged at the second end. Preferably, the two positive locking elements engage in the first and second receiving device.

It is particularly preferred that the tensioning band means comprises a tension band, which preferably extends from the first end body / from the first end plate to the second end body / to the second end plate in the stacking direction in the tensioned and mounted state of the tension band device. Preferably, the tension band is formed as a metal band. The tension band may alternatively be formed from a textile material or a plastic material. Preferably, the tension band is designed so flexible that its two free ends can be combined non-destructive and elastic, in particular reversible. The strap can also be formed slippery.

The tension band has a considerably greater length than width, wherein the length is preferably adapted to an overall height of the stack or depending on this. However, the strap does not necessarily have exactly the length corresponding to the height of the stack. Rather, the clamping band in a longitudinal extent or the length is adjustable or elastic and / or stretchable designed to adapt to the stack height and the stacked body to press each other. The width of the tension band is preferably up to 25 cm, in particular up to 20 cm, in particular up to 15 cm.

It is preferred that the first positive locking element is arranged or fixed at one end and the second positive locking element at the other end of the clamping band. Preferably, the first and / or the second form-fitting element at the ends of the clamping band form, force and / or materially connected thereto. It is particularly preferred that the first and / or second positive locking element is welded to the clamping band when the clamping band is formed as the metal strip.

According to the invention, the first positive locking element is fixed in or on the stack, independently of the second positive locking element, in order to tension the tensioning band device on the outside in the stacking direction and to hold the stacked bodies together in the stack. In particular, the first and second form-locking element are not directly connected to each other in particular by another mounting means and / or they do not hold each other together. It is particularly preferred that the first positive locking element on the first end body / on the first end plate and the second positive locking element are attached to the second end body / on the second end plate by engaging in the first and second receiving means.

An advantage of the invention is that the stack is securely and firmly held together by the engagement of the interlocking elements in the receiving devices of the tensioning band device. Through the engagement of the form-locking elements, a simple and quick installation of the tensioning band device on the stack is possible, whereby costs and time can be saved when assembling the stack. Because the tensioning band device is always tensioned only along one or the outside and is fastened thereto by the form-locking elements on the first and second end bodies / on the first and second end plates, the tensioning band device, in particular the tensioning band, does not need to be complicated around the entire stack be placed. Furthermore, the interlocking elements are not removed from the stack when engaging in the receiving devices, so that advantageously a space requirement or storage space for the stack can be reduced. In particular, it will allows additional components to be attached to one or both end bodies / end plates.

In an optional embodiment of the invention, the tensioning band device comprises two or more tension bands running in parallel. Preferably, the two or more parallel clamping bands together at one end of the first positive locking element and at the other end the second positive locking element. In particular, open all the ends of a page in the same positive locking element. In other words, the two or more tension bands are held together at one end in common by the first positive locking element and at the other end of the second positive locking element in parallel to each other.

The advantage of this embodiment is that the use of a tensioning band device with the two or more tightening straps results in a better introduction of force into the receiving devices and / or into the stack, since the positive locking elements are correspondingly larger or longer and thus larger and / or larger have longer contact surface to the stack.

In a preferred embodiment of the invention, the first positive locking element is adapted to engage in the first receiving device and the second positive locking element to engage in the second receiving device. In particular, the first and / or second positive locking element engages positively in the associated receiving device.

In a preferred constructive implementation of the invention, the first form-fitting element is designed as at least one threaded rod. Preferably, the at least one threaded rod is welded to the tensioning band device, in particular to the tensioning band, when the tensioning band is designed as the metal band. In this case, the threaded rod is preferably aligned in a longitudinal direction of the clamping band and thus in the mounted state on the stack in the stacking direction.

A possible embodiment of the invention provides that the first receiving device is designed as at least one bore in the stack. Preferably, the bore is consumed in the first end body / the first end plate. It preferably opens in a recess provided for a sleeve nut in the first end body / the first end plate. In particular, the bore and / or the recess in the stacking direction is introduced into the part of the first end body / the first end plate projecting from the stack. Optionally, the bore has an internal thread, so that the threaded rod can be easily inserted into the bore, in particular screwed in before or during adjustment and / or clamping of the tensioning band device or the tension band.

It is preferred that the threaded rod is closed after insertion into the bore with the sleeve nut to secure it from slipping out of the hole. For this purpose, the sleeve nut can be inserted into the recess provided for it and fixed on the threaded rod, whereby a clamping force and / or length of the tensioning band device or the tension band can be adjusted and adapted to the stack height. Thus, a tolerance compensation on the tensioning band device can be made, which is advantageously made possible that the tensioning band device, in particular the tension band, can be prefabricated to a certain length. The tensioning band device can preferably be used for a plurality of stacks of different heights, since the tension can be adjusted by tightening the sleeve nut. An additional operation, in which the clamping band device must be shortened accurately, can be saved.

In a preferred embodiment according to the invention, the first positive-locking element and / or the first receiving device has a sealing device. Preferably, the sealing means is disposed on the threaded rod, the sleeve nut and / or in the bore to seal the connection between the threaded rod and the bore. For example, the sealing device may be molded onto a head of the sleeve nut. It is also conceivable that the hole is closed with a blind plug.

In a preferred structural implementation of the invention, the second form-fitting element is designed as an anchor device. Preferably, the anchor device is T-shaped, but it may also have any other suitable external shape or shape. In particular, the anchor device is designed to be positively inserted into the second receiving device and to intervene therein.

A possible embodiment of the invention provides that the second receiving device is formed as a depression on the stack in the form of the anchor device or complementary to the anchor device. Preferably, the recess is inserted in the side surface of the second end body / the second end plate. The recess causes the engaging therein anchor means does not protrude from the side surface of the end body / the end plate. In particular, the anchor device terminates flush with the second end body / second end plate and / or is flush with the side surface thereof. this attached. It is preferable that the second end body / the second end plate has the same dimensions as the other stack bodies (except the first end body / the first end plate) and that it is arranged flush with the outside of the stack.

Preferably, the second positive locking element is secured by a screw in the second receiving device. In particular, the anchor device and the second end body / the second end plate in the recess has a threaded bore into which a screw for additional positive and non-positive securing the anchor device in the recess can be introduced. This can prevent the anchor device from slipping out of the recess during tensioning of the tensioning band device.

A further possible embodiment of the invention provides that the first and / or the second positive locking element are rotatably mounted on the tensioning band device. Due to the rotatable mounting, the mounting of the tensioning band device on the stack can be facilitated and the first and / or the second form-fitting element can be fastened more easily and quickly in the receiving device (s).

In a preferred embodiment of the invention, the stack comprises an elastic element, which is designed to ensure a preferably additional length compensation in the stacking direction during clamping of the tensioning band device. For example, the elastic element may be formed as a leaf, plate or tension spring. It is conceivable within the scope of the invention that a leaf or plate spring is / are arranged on the stack, on and / or below the tension band or in the area of the form-locking element / the form-locking elements. It is also conceivable that the tension band is held together in the longitudinal direction by one or more tension springs or other elastic elements.

In a constructive implementation of the invention, the at least two stacked bodies are designed as fuel cells or corresponding plates. In particular, the stack comprises more than 10, 50 or 100 fuel cells. Preferably, the stack is formed as a fuel cell stack. The stack is optionally designed to generate electricity and to drive a motor vehicle, in particular a car or truck. Usually, sealing plates are arranged between the fuel cells to prevent leakage of hydrogen from the stack. The receiving devices are preferably arranged in the end plates of the stack. It is particularly preferred that the tension band means presses firmly together the fuel cells, the sealing plates and the first and second end plates to ensure the sealing of the hydrogen cells by the sealing plates.

Preferably, when mounting the stack, the anchor piece is first inserted into the recess and optionally secured by the screw against slipping out of the recess. Subsequently, the threaded rod is inserted into the bore, secured by tightening the sleeve nut and readjusted the tensioning band device. By the sealing device on the threaded rod, the bore and / or the sleeve nut can be ensured in an advantageous manner that no hydrogen exits the stack and the fuel cells work reliably.

In a further preferred embodiment, the at least two stacked bodies are formed as ceramic components. The stack is preferably formed as a ceramic assembly for conditioning working gases of one or the fuel cells. In particular, the ceramic components have channels through which a supply of oxidants to the fuel cells and an exhaust air from the fuel cells are performed, wherein the channels are formed in the ceramic components and / or arranged so that they extend over the at least two ceramic components and that Heat and / or moisture transfer takes place between the exhaust air and the supply air. The arrangement of the receiving devices and the tensioning band device (s) can be inferred analogously to the previous description and / or the claims.

Further features, advantages and effects of the invention will become apparent from the following description of preferred embodiments of the invention. Showing:

1 a perspective view of a stack with a plurality of stacked bodies, which are held together by clamping band means as embodiments of the invention;

2 a perspective top view of one of the tensioning band means 1 ;

3 a detail view of a first end of an alternative strap means;

4 a detailed view of a second end of another alternative strap device.

1 shows in a perspective view a stack 1 as a first embodiment of the invention. The stack 1 includes a plurality of parallelepiped, in particular plate-shaped stacked bodies 2 which are stacked in a stacking direction R on each other. The stack 1 is as a fuel cell stack 1 trained, the fuel cell stack 1 a plurality of stacked fuel cells 2 includes and between the fuel cells 2 Sealing plates or seals are arranged.

The stack 1 has a first end and a second end, the first end being through a first end plate 3 and the second termination by a second endplate 4 is formed. The first end plate 3 has a larger width B than the stacked body 2 and the second end plate 4 on top so that they are from an outside A of the stack 1 protrudes.

The end plates 3 ; 4 have two open spaces F and side surfaces S, wherein the open spaces F not to another stacking body 2 connect and are directed in or opposite to the stacking direction R. The side surfaces S are in the perspective view of the stack 1 aligned parallel to the stacking direction R.

At the first and second end plate 3 ; 4 or on the side surfaces S is a first receiving device 5 and a second receiving device 6 arranged. The first recording device 5 is formed as a bore. To the hole 5 joins in the stacking direction R a recess into which a sleeve nut 12 flush with the side surface S of the first end plate 3 can be introduced.

The second recording device 6 is as a T-shaped recess in the side surface S of the second end plate 4 educated. The first and second receiving device 5 ; 6 are for receiving positive-locking elements 9 ; 10 educated.

The stack 1 has two strap devices 7 each having first and second ends E1; E2 have. The first end E1 is on the side of the first end plate 3 , the second end E2 on the side of the second end plate 4 arranged.

The tensioning band device 7 is on the outside A of the stack 1 arranged and adapted to the stacked body 2 in the stacking direction R hold together and squeeze.

At the first end E1 is a first positive locking element 9 , at the second end E2, a second positive locking element 10 arranged, which are adapted to form fit in the first and second receiving device 5 ; 6 intervene so that the tension band means 7 are secured positively in the direction of stacking direction R. The two positive locking elements 9 ; 10 are independent of the stack 1 attached to the strap assembly 7 on the outside A to tension in the stacking direction R and the stacking body 2 in the pile 1 together. So they are not held together by an additional mounting part each other.

On the in 1 not visible and the outside A opposite side, two more tensioning belt devices 7 be arranged in the stacking direction R, which is the stacked body 2 Also on the opposite side to hold together securely.

In 2 is a perspective top view of one of the tensioning band devices 7 out 1 shown. One of the other tensioning belt devices 7 on the opposite side of the stack 1 are arranged, is partially visible.

The tensioning band device 7 includes a strap 8th on the outside A of the stack 1 is arranged, in particular rests and is tensioned in the stacking direction R. The strap 8th is designed as a metal band.

The tensioning band device 7 has at its first end E1 the first positive locking element 9 and at its second end E2, the second positive locking element 10 on, wherein the first positive connection element 9 as a threaded rod and the second positive locking element 10 is designed as an anchor piece.

The threaded rod 9 is on the strap 8th welded and like the strap 8th aligned in the stacking direction R. The threaded rod 9 is positively in the first receiving device 5 introduced as the bore in the first end plate 3 is trained. She is through the into the depression of the end plate 3 inserted sleeve nut 12 against slipping out of the hole 5 secured. Under a head of the sleeve nut 12 is an in 2 invisible sealing device 13 molded, which is adapted to seal the connection to the outside.

The anchor piece 10 has the T-shape for positive engagement in the recess 6 in the second end plate 4 on. Through a screw connection 11 is the anchor piece 10 against slipping out of the recess 6 secured.

The sleeve nut 12 is adapted to the tension of the tensioning band device 7 , in particular the tension band 8th to regulate. A length of the tensioning band device 7 is so at a height of the stack 1 customizable, whereby it can be ensured that the tensioning band device 7 for a plurality of differently high stacks 1 can be prefabricated and not individually cut to each stack height.

Because the anchor piece 10 and the threaded rod 9 positive and flush with the side surfaces S of the end plates 3 ; 4 in the receiving devices 5 ; 6 intervene, they do not stand by these. Thus, in the arrangement of the stack 1 be saved in the vehicle space.

3 shows an alternative tension band device as a second embodiment of the invention. The strap 8th is formed in two parts, with a tension spring 14 is held together. The tension spring 13 is adapted to the tension of the tensioning band device 7 to further regulate.

In an alternative embodiment of the invention, instead of the tension spring 14 Also leaf or plate springs are used to the tension of the tensioning band device 7 continue to regulate. For example, these can be on the stack 1 , in particular between the outside A and the strap 8th be arranged. These additional elastic elements allow z. As a compensation of the so-called. Breathing a fuel cell stack, ie a change in length due to temperature and / or humidity changes.

As shown in detail, the threaded rod is 9 inserted into the hole and through the sleeve nut 12 positively secured. By further turning the sleeve nut 12 is the tension of the tension band 8th enlargeable or reducible.

The threaded rod 9 and / or the sleeve nut 12 is below the side surface S and flush with the flank F of the first end plate 3 arranged. Thus, the free surface F remains free of interference contours, so that this can optionally be used for mounting other components.

In 4 is another alternative embodiment of the tensioning band device 7 shown. The tensioning band device 7 includes two parallel on the outside A of the stack 1 extending tension bands 8th , Both tension bands 8th open into the second T-shaped form-locking element 10 which is opposite to in 2 is shown longer or wider. The second positive locking element 10 engages positively in the recess 6 on side surface S of the second end plate 5 and is through the screw connection 11 secured against slipping out.

Characterized in that the second positive locking element is formed larger or longer, it has a larger contact surface to the second end plate 4 on. This results in a better force introduction of the two clamping bands 8th to the second end plate 4 or to the stack 1 ,

LIST OF REFERENCE NUMBERS

1

stack

2

stack body

3

first end plate

4

second end plate

5

first receiving device

6

second receiving device

7

Clamping band means

8th

strap

9

first positive locking element

10

second positive locking element

11

screw

12

sleeve nut

13

sealing device

14

mainspring

A

outside

B

width

E1

first end

E2

second end

F

open space

S

side surface

R

stacking direction

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 102008040251 A1 [0003]
• DE 102004027694 A [0004]

Claims (10)

Stack ( 1 ) obtained by stacking at least two stacked bodies ( 2 ) is formed in a stacking direction (R), with a first and a second receiving device ( 5 ; 6 ) for receiving a form-locking element ( 9 ; 10 ), with at least one strap device ( 7 ), which is adapted to an outer side (A) of the stack ( 1 ) in the stacking direction (R) to be stretched and the stack body ( 2 ) in the stack ( 1 ), wherein the at least one tension band device ( 7 ) has a first and a second end (E1; E2), wherein at the first end (E1) a first positive-locking element (E1) 9 ) and at the second end (E2) a second form-fitting element ( 10 ), characterized in that the first positive locking element ( 9 ) independent of the second positive locking element ( 10 ) in or on the stack ( 1 ) is fastened or attachable to the strap assembly ( 7 ) on the outside (A) in the stacking direction (R) to tension and the stack body ( 2 ) in the stack ( 1 ). Stack ( 1 ) according to claim 1, characterized in that the first positive-locking element ( 9 ) is adapted to be in the first receiving device ( 5 ) engage positively and wherein the second positive locking element ( 10 ) is adapted to the second receiving device ( 6 ) intervene positively. Stack ( 1 ) according to claim 1 or 2, characterized in that the first positive-locking element ( 9 ) as a threaded rod and the first receiving device ( 5 ) is formed as a bore. Stack ( 1 ) according to one of the preceding claims, characterized in that the first and / or second receiving device ( 5 ; 6 ) in endplates ( 3 ; 4 ) of the stack ( 1 ) is / are introduced. Stack ( 1 ) according to one of the preceding claims, characterized in that the connection between the first receiving device ( 5 ) and the first positive-locking element ( 9 ) by a sealing device ( 13 ) is sealed. Stack ( 1 ) according to one of the preceding claims, characterized in that the second form-locking element ( 10 ) as an anchor device and the second receiving device ( 6 ) as a recess in the form of the anchor device ( 6 ) or complementary to the anchor device ( 6 ) is trained. Stack ( 1 ) according to one of the preceding claims, characterized in that the first and / or the second form-fitting element ( 9 ; 10 ) rotatable on the tensioning band device ( 7 ) are stored. Stack ( 1 ) according to one of the preceding claims, characterized by an elastic element ( 14 ), which is adapted to a length compensation of the tensioning band device ( 7 ) in the stacking direction (R). Stack ( 1 ) according to one of the preceding claims, characterized in that the at least two stackable bodies ( 2 ) are designed as fuel cells and that the stack ( 1 ) is formed as a fuel cell stack (stack). Stack ( 1 ) according to one of the preceding claims, characterized in that the at least two stackable bodies ( 2 ) are formed as ceramic components and that the stack ( 1 ) is formed as a ceramic assembly for conditioning working gases of one or the fuel cells.

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