Functionally testing a leak detection device for checking the sealing tightness of an inspection object filled with a liquid

1 . A test leak device for functional testing of a leak detection device for the leak test of a test specimen within a test chamber of the leak detection device, said test specimen filled with a liquid and having an internal pressure that is lower than atmospheric pressure, comprising

a reservoir filled with a test liquid, wherein the test liquid has a vapor pressure of less than 500 mbar at room temperature, and the reservoir comprises an outlet, and

a pump cooperating with the reservoir and configured to convey the test liquid from the reservoir in such a way that the test liquid escapes from the pump through the outlet in liquid form from the reservoir.

2 . The test leak device according to claim 1 , wherein the pump is a micro-metering pump configured to deliver a flow rate of less than 100 μl of the test liquid from the outlet per conveying operation.

3 . The test leak device according to claim 1 , wherein the test leak device, the pump and/or the outlet are configured to convey the test liquid from the outlet as spray mist.

4 . The test leak device according to claim 1 , wherein the pump comprises a piezo liquid metering device for metering the flow rate to be delivered by the pump per conveying operation.

5 . The test leak device according to claim 1 , wherein the test specimen is a battery, the liquid is an electrolyte or solvent, and/or the test liquid is an electrolyte or solvent.

6 . A method for functional testing of a leak detection device for the leak test of a test specimen filled with a liquid, the test specimen having an internal pressure that is lower than atmospheric pressure, comprising the steps of

evacuating a test chamber of the leak detection device to a pressure lower than atmospheric pressure,

conveying a predetermined amount of a test liquid from a reservoir by a pump cooperating with said reservoir, which test liquid has a vapor pressure of less than 500 mbar at room temperature, into the test chamber,

transporting the delivered amount of test liquid to a detector of the leak detection device, and

detecting the transported amount of test liquid by means of the detector to thereby test the functionality of the detector.

7 . The method according to claim 6 , wherein a flow rate of less than 100 μl of the test liquid is conveyed from an outlet of said reservoir during a conveying operation.

8 . The method according to claim 6 , wherein the test liquid is conveyed from an outlet of said reservoir as spray mist.

9 . The method according to claim 6 , wherein the test liquid is drawn from the test chamber together with residual gas components and/or together with gas components desorbing from a wall of the test chamber and is supplied to the detector without a separate carrier gas being supplied to the test chamber from the outside.

10 . The method according to claim 6 , wherein the detector is a gas detector.

11 . The method according to claim 6 , wherein the detector is operated in a vacuum system with a lower pressure than the pressure within the test chamber.

12 . The method according to claim 6 , wherein the test liquid is accumulated in the test chamber, or in a connecting line connecting the test chamber and a vacuum pump evacuating the test chamber, during a period of time before the test liquid is detected by means of the detector.

13 . The method according to claim 6 , wherein the test liquid is not supplied to the detector until a predetermined pressure limit value is reached in the test chamber.