MONITORING INTERNAL BATTERY CELL PRESSURE

Abstract

The facility features: a detection arrangement (110) designed to be mounted on a battery cell (112), wherein the battery cell (112) has a housing (118) with an opening (120) and a membrane (122) which is deformable and designed to hermetically seal the opening (120) of the housing (118) of the battery cell (112), wherein the detection arrangement (110) is further configured to detect a deformation of the membrane (122) as a result of pressure in the housing (118) of the battery cell (112) exerted on the membrane (122), as a change in the capacitance of a capacitive sensor circuit or as a change in the inductance of an inductive sensor circuit, wherein the membrane (122) is an element of the capacitive or inductive sensor circuit, and wherein the device is configured to output a signal to a battery management system indicating the pressure in the housing (118) of the battery cell (112), wherein the signal is based on the deformation of the membrane (122).

Description

[0001] The present disclosure relates to battery cells and in particular to the monitoring of the internal pressure of battery cells.

[0002] The internal pressure of, for example, lithium-ion battery cells should be kept within safe operating limits at all times to prevent dangerous situations such as fire or explosion. However, due to the aggressive chemistry within lithium-ion battery cells, it is not practical to implement a pressure monitoring sensor inside the battery cell itself. Therefore, the internal pressure of such battery cells cannot be directly monitored.

[0003] US Patent 2009 / 0053586A1 describes a battery with a casing in which a gas space is formed. The casing includes a diaphragm designed to deform in response to pressure changes in the gas space and, in its deformed state, to actuate a switch.

[0004] DE 2948165 A1 describes a capacitive transducer with a flexible membrane and an electrode assembly attached to the membrane.

[0005] DE 19959128 B4 describes a capacitive weight sensor.

[0006] US Patent 2015 / 0226810 A1 describes an arrangement comprising a battery cell and a sensor designed to detect an operating parameter, such as the battery cell's temperature. The sensor is mounted on a substrate and is located within a housing of the battery cell.

[0007] DE 10 2013 113 909 A1 describes a sensor arrangement with a sensor that is arranged in a housing having a bore. A diaphragm is arranged inside the housing between the sensor and the bore.

[0008] DE 10 2012 203 444 A1 describes a battery cell with a housing that has a membrane and a sensor attached to the membrane.

[0009] The present disclosure relates to techniques for monitoring the internal pressure of a battery cell, wherein a membrane, which is part of an outer shell of the battery cell, is an element of a capacitively based or inductively based sensor circuit to measure a change in capacitance or inductance derived from the deformation of the membrane due to the internal pressure of the battery cell. The change in capacitance or inductance, in turn, can be used to derive a value for the internal pressure of the battery cell.

[0010] One embodiment of the invention relates to a device according to claim 1.

[0011] Another embodiment of the invention relates to a battery cell arrangement according to claim 9.

[0012] Another embodiment of the invention relates to a battery management system according to claim 15.

[0013] Although it is not limited to this, an understanding of the various aspects of the present revelation can be obtained from discussing the detailed description provided in conjunction with the drawings. Fig. Figure 1 shows a block diagram of a system for monitoring the internal pressure of a battery cell according to the disclosure. Fig. Figure 2 shows a schematic representation of a battery cell arrangement of Fig. 1. Fig. Figure 3 shows a cross-section of a battery cell. Fig. 2 and the deformation of a battery cell membrane over a number of different values ​​of internal cell pressure. Fig. Figure 4 shows example diagrams of the deformation of a membrane design according to Fig. 3 about the number of different values ​​of the internal cell pressure. Fig. 5 shows the system of Fig. 1, wherein a detection element is designed as a proximity sensor, according to an example implementation. Fig. Figure 6 shows a cross-section of the system of Fig. 5 in a first example detail. Fig. 7 shows the system of Fig. 1, where a detection element according to an example implementation is part of an oscillator circuit. Fig. Figure 8 shows a cross-section of the system of Fig. 5 in a second example detail. Fig. Figure 9 shows a cross-section of the system of Fig. 5 in a third example detail. Fig. Figure 10 shows several perspective views of a substrate of Fig. 9. Fig. Figure 11 shows a cross-section of the system of Fig. 7 in a first example detail. Fig. Figure 12 shows several perspective views of a substrate of Fig. 11. The Fig. Figures 13-16 collectively show several views of an inductor element and / or coils of an inductor element integrated on a semiconductor die or chip. Fig. Figure 17 shows a diagram of an internal cell pressure acting on a membrane of a battery cell assembly of Fig. 1 is exercised over time.

[0014] The present disclosure relates to techniques for monitoring the internal pressure of a battery cell, wherein a membrane, which is part of an outer shell of the battery cell, is used as an element of a capacitive-based or inductive-based sensor circuit to measure a change in capacitance or inductance derived from the deformation of the membrane as a result of the internal pressure of the battery cell. The change in capacitance or inductance, in turn, can be used to derive a value for the internal pressure of the battery cell. Such an implementation is advantageous in many respects. For example, the sensor circuit, as consistently provided, is located outside the battery cell and is therefore not exposed to the aggressive chemicals inside the battery cell.As another example, as soon as monitoring electronics coupled to the sensor circuit detect overpressure within the battery cell, the monitoring electronics (possibly integrated into a battery management system) can interrupt the current flow through the battery cell by opening a main battery switch, thereby disconnecting the battery cell from a load. Therefore, a current interrupt device (CID), which is used in typical or conventional implementations, can be removed or omitted. However, importantly, the invention of the present disclosure is not limited to this (current flow interrupt switch), as another application would be to improve condition prediction, as mentioned below.Another application would be throttling (reducing) the load or charging current to limit additional pressure build-up and thereby prevent battery disconnection. Additionally or alternatively, since the battery management system is aware of the overpressure, it can trigger an action such as notifying the driver of a vehicle about the overpressure. Furthermore, it is considered that the safety level of the battery cell can be improved due to the enhanced diagnostic capabilities resulting from the features or aspects of this disclosure. Other advantages arise from the techniques of this disclosure, as discussed in conjunction with the drawings.

[0015] For example, it shows Fig. 1 A block diagram of a system 100 for monitoring an internal pressure of a battery cell according to the disclosure. In this example, the system 100 includes a battery cell arrangement 102 (equivalent to a device) and a battery management system 104, and Fig. Figure 2 shows a detailed schematic representation of the battery cell arrangement 102 according to an example detail. The system optionally includes 100 cells, as indicated by a dashed line in Figure 1. Fig. 1 indicated, a switch 106 and at least one load 108. In practice, a detection arrangement 110 of a battery cell arrangement 102 is configured to be mounted on a battery cell 112 of a battery cell arrangement 102 between corresponding terminals 114, 116 of the battery cell (merely as an example that the battery cell arrangement 112 could be mounted anywhere on the outside of the battery cell 112), wherein the battery cell 112 has a housing 118 with an opening 120 and a membrane 122, which is deformable and configured to hermetically seal the opening 120 of the housing 118 of the battery cell 112.The detection arrangement 110 is further configured to detect a deformation or deflection of the membrane 122 as a result of a pressure (internal cell pressure) within the housing 118 of the battery cell 112 exerted on the membrane 122, and the battery cell arrangement 102 is configured to output a signal 124, which indicates the pressure within the housing 118 of the battery cell 112, to the battery management system 104, wherein the signal 124 is based on the deformation of the membrane 122.

[0016] Additionally, a detection element 126 of the detection arrangement 110 is configured to be arranged adjacent to the membrane 122 of the housing 118 of the battery cell 112, and a measuring unit 128 of the detection arrangement 110 is configured to measure a physical parameter of the detection element 126, which depends on the deformation of the membrane 122, for the battery cell arrangement 102 in order to output the signal 124.Additionally, a receiving unit 130 of the battery management system 104 is configured to receive the signal 124 from the battery cell arrangement 102, which indicates an internal pressure of the battery cell 112, and a processing unit 132 of the battery management system 104 is configured to determine a value of the internal pressure of the battery cell 112 based on the signal 124 and to generate a command signal 134 to electrically disconnect the battery cell 112 from the load 108 by controlling the state of the switch 106 when the value of the internal pressure of the battery cell 112 is greater than or equal to a threshold pressure value.In this way, the present disclosure relates to techniques for monitoring the internal pressure of a battery cell, wherein a membrane, which is part of an outer shell of the battery cell, is used as an element of a capacitively based or inductively based circuit to measure a change in capacitance or inductance upon deformation of the membrane in relation to the internal pressure of the battery cell. The change in capacitance or inductance, in turn, can be used to derive a value for the internal pressure of the battery cell.

[0017] Specifically, the detection element 126 is designed to detect a deformation of the membrane 122 as a result of pressure exerted on the membrane 122 within the housing 118 of the battery cell 112. An example of the deformation of the membrane 122 is shown in the Fig. Figures 3-4 are shown. In particular, it shows Fig. 3 a cross-section of battery cell 112 of Fig. 2 and the deformation of the membrane 122 of the battery cell 112 over a number of different values ​​of the internal cell pressure, and Fig. Figure 4 shows diagrams 402 and 404 of the deformation of membrane 122. Fig. 3 on the number of different values ​​of the internal cell pressure. In this example, the abscissa of diagram 402 corresponds to the length along the x-axis of membrane 122, as shown in Fig. 2 is shown, and the abscissa of diagram 404 corresponds to the length along the y-axis of membrane 122, as shown in Fig. 2 is shown. With reference to Fig. 4 alone, the deformation D of the membrane 122 generally increases with increasing internal cell pressure P (D0, P0 < D1, P1 < D2, P3 < D3, P4), as it relates to the ambient pressure P UMGEBUNGis measured, whereby the deformation of membrane 122 is negligible at an internal cell pressure of zero (0), unless membrane 122 has undergone plastic deformation, which is discussed below in connection with at least Fig. 17 is discussed. Since the membrane 122 deforms or deflects under the load of the internal cell pressure, it is considered that the membrane 122 can be used as an element of a capacitively based or inductively based sensor circuit to measure a change in capacitance or inductance when the membrane 122 is deformed by the internal pressure of the battery cell 112. The change in capacitance or inductance, in turn, can be used to derive a value for the internal pressure of the battery cell 112. The operating principle of such a sensor circuit, as is considered, is discussed in connection with at least the Fig. 5-7 discussed.

[0018] In particular, it shows Fig. 5 the system 100 of Fig. 1, wherein the detection element 126 (equivalently the battery cell arrangement 102) is configured as a proximity switch according to an example implementation. Fig. Figure 6 shows a cross-section of the system of Fig. 5 according to a first detailed example. Specifically, the detection element 126 is attached to a substrate 136, such as a top surface of the substrate 136, a bottom surface of the substrate 136, or within or embedded in (embedded in) the substrate 136, or any combination thereof, as shown by the dashed line in Fig. 6 indicated, assembled. In this example, it is considered that the battery cell arrangement 102 is configured to output the signal 124, wherein a deflection D of the membrane 122 under a load of the internal cell pressure is encoded in the amplitude A of the signal 124 (e.g., amplitude A = deformation D). MAX = D KALIBRIERUNG - D ERFASSUNG , as in Fig. 6 shown). It is further considered that the battery management system 104 is configured to receive the signal 124 and correlate the amplitude A of the signal 124 (e.g., based on a lookup in a table or another implementation algorithm) with a specific internal cell pressure P, so that in practice the battery management system 104 can generate a command signal 134 to electrically disconnect the battery cell 112 from the load 108 (only as an example) by controlling the state of the switch 106 when the value of the internal pressure of the battery cell 112 is greater than or equal to a threshold pressure value (see Fig. 1) For example, the battery management system 104 can, under load conditions where the internal cell pressure P is determined to be greater than or equal to the pressure P3 (4.9 bar), as in Fig. As shown in Figure 4, a command signal 134 is generated to electrically disconnect the battery cell 112 from the load 108. Referring to Fig. 5 alone, the battery cell arrangement 102 can be configured as a capacitive proximity switch or as an inductive proximity switch, wherein in Fig. 5 the amplitude A of signal 124 as a function of the deformation D (D MAX ) over an elastic deformation range of the membrane 122 for implementations with both a capacitive proximity sensor and an inductive proximity sensor according to the principles of the present disclosure. A person skilled in the art will recognize that the development trend for the amplitude A, as in Fig. Figure 5, illustrating examples of both the capacitive and inductive proximity sensors, shows that the amplitude A can be implementation-specific and can generally assume a desired shape or form, provided that the amplitude A can be uniquely correlated with a specific internal cell pressure within the specification tolerance. The elastic deformation range 122 is described below in conjunction with at least the following: Fig. 17 discussed.

[0019] In contrast, it shows Fig. 7 the system 100 of Fig. 1, wherein the sensing element 126 (equivalent to the battery cell arrangement 102) is configured as a sensing element as part of an oscillator circuit (equivalent to a resonance sensor) according to an example implementation. In this example, it is considered that the battery cell arrangement is configured to output the signal 124, wherein the deformation D of the membrane 122 under load from the internal cell pressure is encoded into a frequency F of the signal 124 (e.g., frequency F = deformation D). MAX - ΔD, where ΔD is an error offset and a function of D CALIBRATION is as in Fig. 6), and a value for the frequency F (e.g., F = 1 kHz) of the signal 124 is based on the degree of coupling of the electric or magnetic field between the sensing element 126 and the membrane 122. It is further considered that the battery management system 104 is configured to receive the signal 124 and correlate the frequency F of the signal 124 (e.g., based on a table lookup or other implementation-specific algorithm) with a specific internal cell pressure P, so that in practice the battery management system 104 can generate a command signal 134 to electrically disconnect the battery cell 112 from the load 108 (only as an example) by controlling the state of the switch 106 when the value of the internal pressure of the battery cell 112 is greater than or equal to a threshold pressure value.

[0020] In general, the battery cell arrangement 102 can be configured as a capacitive sensing element as part of an oscillator circuit or as an inductive sensing element as part of an oscillator circuit, wherein a frequency F of the signal 124 is a function of the deformation D (D MAX ) of the membrane 122 over an elastic deformation range of the membrane 122 in Fig. Figure 7 illustrates an implementation of both a capacitive sensing element as part of an oscillator circuit and an inductive sensing element as part of an oscillator circuit. A person skilled in the art will recognize that the development trend for the frequency F, as shown in Fig. 7. As shown for the examples of both the capacitive sensing element as part of an oscillator circuit and the inductive sensing element as part of an oscillator circuit, the implementation can be specific and can generally assume any desired shape or form, provided that the frequency F can be uniquely correlated with a given internal cell pressure within the specification tolerance. Example architectures or topologies for the sensor circuit, as used in conjunction with at least the Fig. 5-7 are discussed, are still in the Fig. 8-16 shown.

[0021] For example, it shows Fig. 8 a cross-section of the system of Fig. 5 according to a second example detail. In this example, it is considered that several slats 806a-c (three as in Fig. 8 shown, although other examples are possible) can be mounted on the membrane 122 or on the substrate 136, wherein the lamellae 806a-c (e.g. made of rubber and ceramic) are arranged in a nested manner with respect to one another and are designed to be detached as a result of a pressure within the housing 118 of the battery cell 112 exerted on the membrane 112 of the housing 118 of the battery cell 112 (see Fig. 2) to slide into one another. In practice, the extent of an overlap is 808 (see Fig. 8) between corresponding lamellae 806a-c proportional to an achieved or effective permittivity of the medium between the lamellae 806a and 806b, which form plates of a capacitor 804. For example, the effective permittivity for a first overlap distance O1 is greater than the effective permittivity for a second overlap distance O2 if the first overlap distance O1 is greater than the second overlap distance O2 (see the overlap distance O in Fig. 8) is.

[0022] In this example, the capacitance between the laminations 806a and 806b, which form the plates of a capacitor 804, is greater due to expansion for the first overlap distance O1 than the capacitance between the laminations 806a and 806b for the second overlap distance O2 according to the relationship C=εA / d. Fig. In section 8, the plates of capacitor 804 are formed by the "upper" lamellae 806a and 806b. The "lower" lamella 806c is not a capacitor plate, but a dielectric material that is pushed between the "upper" lamellae 806a and 806b by the deformation of the membrane 122. This, in turn, changes the capacitance between the lamellae 806a and 806b by altering the permeability of the material between them. Other example architectures or topologies for the sensor circuit, as used in conjunction with at least the Fig. Items 5-7 will be discussed and considered.

[0023] For example, it shows Fig. 9 a cross-section of the system of Fig. 5 according to a third example detail. Fig. Figure 10 shows several perspective views of the substrate (PCB) 136 of Fig. 9. More precisely, a metallic (e.g., aluminum) membrane 122, which is part of an outer shell 118 of the battery cell 112 (see Fig. 2) is used as an element of a capacitive-based sensor circuit to measure a change in capacitance when the membrane 122 is deformed due to the internal pressure of the battery cell 112. The change in capacitance, in turn, can be used to derive a value for the internal pressure of the battery cell 112. In this example, an annular electrode surface 902 formed on (or embedded in) the substrate 136, a disk-shaped electrode surface 904 formed on the substrate 136, and a membrane 122 together define the first, second, and third electrodes of a capacitor element 906, wherein electrical contact with the annular electrode surface 902 and the disk-shaped electrode surface 904 is, in one example, by (over) dielectric surface layers 1002 and 1004, respectively, as in Fig. 10 is shown, formed. Other examples are possible.

[0024] In practice, a change in the distance between the corresponding electrode surfaces 902, 904 and the membrane 122, due to deformation of the membrane 122 under the internal cell pressure of the battery cell 112, is converted into a change in capacitance according to the relationship C = εA / d, which is approximated in the example implementation. This is because the poles of the capacitor element 906 are positioned on one side of the substrate 136, using the membrane 122 as a common (internal) plate, which can be considered a series connection of two capacitors formed by the electrode surfaces 902, 904 and the membrane 122. Nevertheless, the change in capacitance can in turn be measured by any capacitive proximity switch or capacitive sensing element as part of an oscillator circuit, as described above in conjunction with the Fig. 5-7 discussed, can be used to derive a value for the internal pressure of battery cell 112 in accordance with the principles of the present disclosure. Other example architectures or topologies for the sensor circuit, as used in conjunction with at least the Fig. Items 5-7 will be discussed and considered.

[0025] For example, it shows Fig. 11 a cross-section of the system of Fig. 7 according to a first example detail. Fig. Figure 12 shows several perspective views of a substrate (PCB) of Fig. 11. In detail, the membrane 122, which is part of an outer shell (housing) 118 of the battery cell 112, is used as an element of an inductively based sensor circuit to measure a change in inductance when the membrane 122 is deformed by the internal pressure of the battery cell 112. The change in inductance, in turn, can be used to derive a value for the internal pressure of the battery cell 112. In this example, the inductance element 1102 is formed on a substrate 136 (or embedded therein, or any combination thereof), wherein the electrical contact with the inductance element 1102 is, in one example, by (via) a dielectric surface layer 1202, as shown in Fig. Figure 12 shows that an inductance element 1102 can generally correspond to any printed (planar) inductance, discrete (non-planar) inductance, or inductance integrated into an integrated circuit or semiconductor die or chip 1104. For example, the Fig. Figures 13-16 jointly show several views of an inductor element 1102 and / or coils of the inductor element 1102, which is integrated on a semiconductor die or chip 1104. Therefore, as a person skilled in the art understands, the inductor element 1102, as shown in connection with the Fig. 11-16 shown and described, correspond to any printed (planar) inductor, discrete (non-planar) inductor and inductor integrated into an integrated circuit or semiconductor die or chip 1104.

[0026] With reference to the Fig. In practice, a change in the distance between the inductor element 1102 and the membrane 122 due to deformation of the membrane 122 under a load of an internal cell pressure of the battery cell 112 is converted into a change in inductance according to the relationship L = NΦ / I, where N is the number of turns of a coil of the inductor element 1102, Φ is the magnetic flux linkage, which is a function of the distance between the inductor element 1102 and the membrane 122, and I is the magnitude of the current flowing through the inductor element 1102 in amperes at a bias. This change in inductance, in turn, can be detected by any inductive proximity sensor or inductive sensing element as part of an oscillator circuit, as described above in conjunction with the Fig. 5-7 discussed, can be used to derive a value for the internal pressure of battery cell 112 according to the principles of the present disclosure.

[0027] As mentioned above, the elastic deformation range of the membrane 122 (the Fig. 1-16) in conjunction with at least Fig. 17 discussed. In detail, it shows Fig. 17 a diagram 1702 of the membrane 122 of the battery cell arrangement 102 of Fig. 1. Internal cell pressure exerted over time according to an example. In this example, the ordinate axis is divided into an instability zone 1704, a zone 1706 of plastic deformation, and a zone 1708 of elastic deformation. Under normal conditions, the internal cell pressure exerted on the membrane 122, from the perspective of the battery cell, is such that the membrane 122 undergoes elastic deformation. That is, the structural integrity of the membrane 122 is not compromised as long as the internal cell pressure exerted on the membrane 122 remains within the zone 1708 of elastic deformation. Depending on how long (in terms of time) such pressures are maintained, the structural integrity of the membrane 122 may be compromised if the internal cell pressure exerted on the membrane 122 is within the zone 1406 of plastic deformation.If the structural integrity of membrane 122 is compromised, it may not relax to a uniform initial state. This can lead to inaccuracies in determining the deflection D of membrane 122 and, due to expansion, to inaccuracies in determining the internal cell pressure P of battery cell 112 in the manner generally considered. To address such a problem, a calibration procedure can be implemented through the battery cell assembly 102 to determine a parameter D. CALIBRATION (see Fig. 6) to determine in order to account for this error offset, so that the actual deformation of the membrane 122 can be derived or determined. Finally, the structural integrity of the membrane 122 can be permanently destroyed if the internal cell pressure exerted on the membrane 122 reaches the instability zone 1704. In practice, it is considered that a system readout from a diagnostic and / or user interface-related circuit could provide a real-time display of the state of the membrane 122 (instability zone 1704, zone 1706 of plastic deformation, zone 1708 of elastic deformation).

[0028] With reference to the information associated with the Fig.As discussed in paragraphs 1-17, the present disclosure relates to techniques for monitoring the internal pressure of a battery cell, wherein a membrane, which is part of an outer shell of the battery cell, is an element of a capacitively based or inductively based sensor circuit to measure a change in capacitance or inductance due to deformation of the membrane in relation to the internal pressure of the battery cell. The change in capacitance or inductance can be used to derive a value for the internal pressure of the battery cell, and it will be recognized that the topology of the capacitively based or inductively based sensor circuit can be implementation-specific. For example, the capacitively based sensor circuit or the inductively based sensor circuit can correspond to an RC or an RL oscillator, respectively, with the frequency of the oscillator then being measured by a microcontroller.Other solutions, such as a Wien-Robinson oscillator or a constant current source for charging a capacitor to monitor the change in capacitor voltage over time, can be used for capacitive-based sensor circuit implementations.

[0029] For inductively based sensor circuit implementations, a fundamental way to detect a change in the magnetic flux of an environment is to generate an oscillator containing a coil located close to the component being monitored. If the component moves or deforms, the resulting oscillator frequency changes accordingly. To achieve high resolution and noise immunity (from the environment), an averaging filter can be used. An averaging filter can be formed by a counter that counts the number of oscillator periods during a specific time window. The result of the counter at the end of the counting window can indicate the distance or shape of the component being monitored relative to the coil. If there are certain known frequency components in the ambient noise (e.g.,Due to the switching operation of a power inverter, the window length of the averaging filter can be adjusted so that it always contains a similar length of switching events during the time window (synchronization of the counting window and the power inverter). The inductor itself can be constructed in many different ways. A "real" inductor with several turns as a separate component can be more expensive than a printed version on a PCB. The printed version can have a lower inductance. If a printed version is used, the PCB can carry a sensing element that contains the rest of the oscillator and some measurement units, such as for counting the oscillator periods or an independent time base as a frequency reference. Another possibility is to use an inductor that is integrated into / onto an integrated circuit chip itself, along with other component blocks of the sensing element.Similarly, the entire oscillator and measurement blocks can be implemented in a single device. With the inductive approach, the sensing element can be completely enclosed, and additional geometric elements are not necessarily required. For example, there are coils that are already monolithically integrated, particularly for high-frequency applications or to achieve galvanic isolation in gate drivers for power switches.

Claims

[1] Facility that features: a detection arrangement (110) designed to be mounted on a battery cell (112), wherein the battery cell (112) has a housing (118) with an opening (120) and a membrane (122) which is deformable and designed to hermetically seal the opening (120) of the housing (118) of the battery cell (112), wherein the detection arrangement (110) is further configured to detect a deformation of the membrane (122) as a result of pressure in the housing (118) of the battery cell (112) exerted on the membrane (122), as a change in the capacitance of a capacitive sensor circuit or as a change in the inductance of an inductive sensor circuit, wherein the membrane (122) is an element of the capacitive or inductive sensor circuit, and wherein the device is configured to output a signal to a battery management system indicating the pressure in the housing (118) of the battery cell (112), wherein the signal is based on the deformation of the membrane (122). [2] Device according to claim 1, further comprising: a printed circuit board (136) designed to be arranged at a predetermined distance from and adjacent to the membrane (122), wherein the capacitive sensor circuit has a first capacitive element with a first electrode surface (904) and a second electrode surface, wherein the first electrode surface (904) is on the circuit board (136) and the second electrode surface, when the detection device is mounted on the battery cell, is formed by the membrane (122) of the housing (118) of the battery cell (112). [3] Device according to claim 2, wherein the capacitive sensor circuit further comprises a second capacitive element connected in series with the first capacitive element and having an electrode surface (904), wherein the electrode surface (902) of the second capacitive element is formed on the circuit board (136) and is electrically insulated from the first electrode surface (904) of the capacitive element, wherein the electrode surface (902) of the second capacitive element and the second electrode surface of the first capacitive element, when the sensing arrangement is mounted on the battery cell (112), form electrodes of the second capacitive element. [4] Device according to claim 3, wherein the first electrode surface (904) of the first capacitive element is formed as a disk-shaped structure on the circuit board (136) and the electrode surface (902) of the second capacitive element is formed as a ring-shaped structure surrounding the disk-shaped structure on the circuit board (136). [5] Device according to claim 2, wherein a first set of lamellae (806a, 806b) on the first electrode surface of the first capacitive element are arranged in a nested manner with respect to a second set of lamellae (806c) which are arranged on the second electrode surface of the first capacitive element when the sensing arrangement is mounted on the battery cell, wherein the first set of lamellae (806a, 806b) and the second set of lamellae (806c) are designed to slide into each other as a result of pressure being exerted on the membrane (122). [6] Device according to claim 5, wherein the first set of lamellae (806a, 806b) and the second set of lamellae (806c) are made of rubber and ceramic. [7] Device according to claim 1, further comprising: a printed circuit board (136) which is designed to be arranged at a predetermined distance from and adjacent to the membrane (122), wherein the inductive sensor circuit comprises an inductive element (1102) which is arranged on the circuit board (136). [8] Device according to claim 7, wherein the inductive element comprises a discrete inductance element or a planar inductance element printed on the printed circuit board (136). [9] Battery cell arrangement comprising: a battery cell (112) comprising a housing (118) with an opening (120) and a membrane (122) which is deformable and designed to hermetically seal the opening (120) of the housing (118), and a device according to any one of claims 1 to 8, wherein the detection arrangement is arranged at a predetermined distance from and adjacent to the membrane (122) of the housing (118). [10] Battery cell arrangement according to claim 9, wherein the membrane (122) of the housing (118) is a pressure release membrane designed to release excess pressure inside the battery cell (112) through the opening (120) of the housing (118). [11] Battery cell arrangement according to claim 9 or 10, wherein the membrane (122) of the housing (118) comprises a metal element. [12] Battery cell arrangement according to claim 11, wherein the metal element comprises aluminium. [13] Battery cell arrangement according to claim 9 or 10, wherein the membrane (122) of the housing has a ferromagnetic element. [14] Battery cell arrangement according to claim 13, wherein the ferromagnetic element comprises ferrite. [15] Battery management system which features: a receiving unit configured to receive from a battery cell arrangement according to one of claims 9 to 14 a signal indicating an internal pressure of a battery cell (112), and a processing unit designed to determine a value of the internal pressure of the battery cell (112) based on the signal received from the battery cell assembly and to generate a command signal to electrically disconnect the battery cell (112) from a load when the value of the internal pressure of the battery cell (112) is greater than or equal to a threshold pressure value.

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