The testing device 1 is used to detect defective or damaged segments 2 so that they are not used to form the cell stacks with the cell stacking devices 18. For the sake of simplicity, the term “defective segments 2” is used below, wherein this means all segments 2 that do not meet the specified quality requirements. In this exemplary embodiment, the testing device 1 itself is not configured to eject defective segments 2 from the production process. In this exemplary embodiment, this is done by an ejection drum 25 that ejects the defective segments into a reject reservoir (not shown). In this case, the testing device 1 comprises a conveying apparatus 3 in the form of a testing drum mounted to rotate about an axis of rotation 14. A transport drum 20 is provided between the conveying apparatus 3 and the ejection apparatus 25. The direction of rotation of the drums is indicated by arrows 28, only two of which are provided with the corresponding reference sign. By ejecting faulty segments 2 by means of the ejection drum 25, it can be ensured that only faultless segments 2 are used to form the cell stacks with the cell stacking devices 18.

FIG. 2 shows the conveying apparatus 3 in the form of a test drum that is mounted so that it can rotate about the axis of rotation 14. The conveying apparatus 3 has a plurality, for example between 3 and 19, further for example between 10 and 16, of receiving portions 4a, 4b, 4c on a radially outer lateral surface 19, each of which is configured to receive and transport a segment 2. The conveying apparatus 3 shown here comprises exactly twelve of the receiving portions 4. The conveying apparatus 3 rotates relative to a stationary part 5 of the testing device 1 shown schematically in FIG. 4. The receiving portions 4a, 4b, 4c visible here can be subjected to a vacuum so that the segments 2 are held on the receiving portions 4a, 4b, 4c by the effect of the vacuum. This also allows the segments 2 to be received and handed over in a way that is gentle on the product.

Each of the receiving portions 4a, 4b, 4c has a first contact surface 6, a second contact surface 7 and a third contact surface 8, wherein these are electrically insulated from each other and from the remaining part of the conveying apparatus 3. The receiving portion 4b is covered with a segment 2 so that the third contact surface 8 of the receiving portion 4b is covered by the segment 2. However, it can be seen that a first electrode 22 contacts the first contact surface 6 by means of its conductor lug 11. It can also be seen that a second electrode 24 contacts the second contact surface 7 by means of its conductor lug 12. The contacting of the segment 2 with the third contact surface 8 of the receiving portion 4b is described below with reference to FIG. 3.

FIG. 3 is a sectional view of a segment 2 arranged on the conveying apparatus 3, wherein the section is arranged in a plane orthogonal to the axis of rotation 14 (see FIG. 2) of the conveying apparatus 3. The sectional view in FIG. 3 shows the receiving portion 4b from FIG. 2. The receiving portion 4b comprises the third contact surface 8, which is electrically insulated from the rest of the receiving portion 4b and therefore also from the rest of the conveying apparatus 3 by means of an insulator 16. The segment 2 rests with the first separator 21 on the third contact surface 8, which simultaneously forms a suitable transport support for the segment 2. It can also be seen that the flat extension of the third contact surface 8 coincides with the main surface of the first and second electrodes 22 and 24 without taking into account the conductor lugs 11, 12 (not shown here).

In this way, the third contact surface 8 together with the first electrode 22 arranged above the first separator 21 can form a pair of electrodes that is suitable for testing the first separator 21 arranged therebetween. The first electrode 22 is then contacted via the first contact surface 6 as shown in FIG. 2.

FIG. 3 also shows that the first electrode 22 is followed by the second separator 23 and the second electrode 24. The first electrode 22 and the second electrode 24 therefore form an electrode pair that is suitable for testing the second separator 23 arranged therebetween.

FIG. 4 is an additional sectional view of the segment 2 arranged on the conveying apparatus 3, wherein the section is arranged in a plane parallel to the axis of rotation 14 (see FIG. 2) of the conveying apparatus 3. In this illustration, it can be seen that the first electrode 22 contacts the first contact surface 6 by means of its conductor lug 11. It can also be seen that the second electrode 24 makes contact with the second contact surface 7 by means of its conductor lug 12. In order to prevent the conductor lugs 11, 12 from kinking, the contact surfaces 6, 7 have a correspondingly adapted height in the radial direction; the height in the radial direction of contact surface 6 is therefore less than the height of contact surface 7.

FIG. 5 is a schematic representation of the testing device 1 comprising the conveying apparatus 3, which is rotatably mounted relative to the stationary part 5. The arrow 28 shows the rotational movement of the conveying apparatus 3 in the form of a test drum, which rotational movement can be effected by an actuator 31. The actuator 31 is controlled or regulated by a control unit 30. Both the control unit 30 and the actuator 31 are assigned to the stationary part 5. Furthermore, the twelve receiving portions 4a, 4b, . . . , 4l are shown schematically, each of whose three contact surfaces 6, 7, 8 are connected electrically and/or by signal to a switching matrix 9 via three lines 33. Thus, each of the receiving portions 4a, 4b, . . . , 4l is connected to the switching matrix 9 via three lines 33.

The switching matrix 9 comprises a plurality of relays 29a, 29b, 29c that are configured to connect the lines 33 to input lines 34. FIG. 5 shows only the three relays 29a, 29b and 29c, which are representative of a large number of relays. By means of a sliding contact apparatus 13, the input lines 34 rotating with the conveying apparatus