Battery with temperature measuring device

Abstract

A battery (20) includes a plurality of individual battery cells (21). The battery (20) has at least one temperature measuring device (10). The temperature measuring device (10) includes a multilayer circuit board (1) having an upper conductive layer (1a) and a lower conductive layer (1b) as a carrier element; a plurality of temperature sensors (2), each temperature sensor (2) being configured to generate a temperature-related measurement signal; and a multi-pole terminal (11) for reading the measurement signal. In each case, the plurality of temperature sensors (2) are each arranged in a first insulating region (5a) of the upper conductive layer (1a). For each temperature sensor (2), the lower conductive layer (1b) has a second insulating region (5b) as a thermal contact surface. In each case, the first insulating region (5a) is thermally connected to the corresponding second insulating region (5b) via at least one through connection (4). The second insulating regions (5b) are each thermally connected to at least one battery element connector (22) of the battery (20).

Description

Technical Field

[0001] The present invention relates to a battery having a temperature measuring device for measuring the temperature of the battery at multiple measuring locations. Background Technology

[0002] The published patent application DE 102016 207334 A1 discloses a measuring device for determining temperature, comprising a multilayer circuit board and a sensor device disposed thereon. The conductive layers are arranged in a nested manner, with some overlapping areas.

[0003] A temperature measuring device for a battery system is known from European patent EP 2736100 B1. Multiple infrared temperature sensors for measuring the temperature of the battery cells are arranged on a circuit board. The sensors are mechanically separated from the battery cells.

[0004] International patent application WO 2016 / 153267 A1 describes a battery pack including at least one battery cell, a heat sink for dissipating heat generated by the battery cell, a circuit board having a portion in contact with the heat sink, and a temperature sensor mounted on the circuit board for measuring heat conducted from the heat sink to the circuit board.

[0005] Korean patent application KR 1020180043875 A describes another device for measuring the temperature of a battery pack. Further, WO 2015 / 019511 A1 discloses a battery comprising multiple battery cells and a circuit board, the circuit board including a temperature sensor for measuring the temperature of the battery. Summary of the Invention

[0006] General-type batteries are particularly used as energy storage devices for powering buildings. Such batteries consist of a large number of individual battery cells that can be connected in series or parallel. Monitoring the temperature of the battery cells is crucial, especially when the battery has a large number of individual battery cells. One object of this invention is to provide a battery with a temperature measuring device that, if possible, can monitor the temperature of all battery cells.

[0007] The battery temperature measuring device according to the present invention includes a multilayer circuit board having an upper conductive layer and a lower conductive layer as a carrier element. Specifically, the circuit board is made of a heat-insulating material, thus having a low heat capacity. Therefore, the temperature measuring device itself absorbs only a small amount of heat from the battery under test. Consequently, the accuracy and response speed of the temperature measuring device can be improved.

[0008] Temperature measurement devices include multiple temperature sensors, each configured to generate a temperature-dependent signal. By using multiple sensors, the temperature of a battery with multiple individual cell units can be monitored at multiple measurement points. This ensures particularly reliable temperature monitoring. Specifically, the temperature sensors are temperature-dependent resistors, such as negative temperature coefficient thermistors (NTC thermistors). Such resistors conduct current better at higher temperatures than at lower temperatures. NTC thermistors can be particularly inexpensive, offer high measurement accuracy, and are very reliable. However, their use is not limited to NTC thermistors; PTC thermistors or other chip solutions may also be used in measurement devices.

[0009] Multiple temperature sensors are preferably arranged at intervals along the longitudinal direction of the circuit board. The positions of the sensors can be specified, in particular, by the arrangement of the individual battery cells of the battery under test. By arranging the sensors uniformly on the circuit board, it is particularly possible to measure and monitor the uniform temperature distribution of the individual battery cells.

[0010] The circuit board of the temperature measuring device includes multiple fixing devices for securing the circuit board to the battery. Specifically, each fixing device is arranged at the level of the sensor to create direct contact with a portion of the battery under test.

[0011] The temperature measuring device includes a multi-terminal for reading measurement signals. Specifically, the multi-terminal includes multiple signal poles, each electrically connected to one of a plurality of temperature sensors via a separate conductor rail on an upper conductive layer. Further, the multi-terminal preferably includes at least one ground pole (GND), which is electrically connected to each of the plurality of temperature sensors via at least one conductor rail. Therefore, the conductor rails of the upper conductive layer can be configured such that a first contact point of each temperature sensor is connected to the ground conductor rail, and a second contact point of each temperature sensor is connected to a separate signal conductor rail, so that individual temperature or resistance values ​​can be read by each temperature sensor.

[0012] Multiple temperature sensors are each disposed on a first insulating region of the upper conductive layer. This first insulating region specifically serves as the thermal contact surface with the respective temperature sensor. The first insulating region is electrically insulated from the conductor track.

[0013] The lower conductive layer includes a second insulating region, which serves as a thermal contact surface with the object under test for each temperature sensor. The thermal contact surface of the lower conductive layer is configured such that it can be directly positioned on the surface of the battery under test and make thermal contact with that surface.

[0014] Each of the first insulating regions is thermally connected to a corresponding second insulating region via at least one through-connection. The through-connection through the insulating circuit board creates a thermally conductive connection between the thermal contact surface in direct contact with the battery and the corresponding temperature sensor. Specifically, each of the first insulating regions is thermally connected to a corresponding second insulating region via multiple through-connections, for example, three or more through-connections. Therefore, thermal conduction between the temperature sensor and the corresponding thermal contact surface can be improved, thereby enabling accurate measurement of the temperature on the underside of the circuit board.

[0015] Each temperature sensor is preferably surrounded by a thermally conductive sheath, which is thermally connected to the corresponding first insulating region. The thermally conductive sheath improves heat transfer from the first insulating region to the temperature sensor. In particular, heat is evenly distributed throughout the entire periphery of the temperature sensor, thereby enabling more accurate temperature measurement.

[0016] Preferably, the circuit board has numerous cuts. These cuts reduce the total surface area and mass of the temperature measuring device. This reduces the total heat capacity of the temperature measuring device, improving measurement accuracy because the device absorbs less heat from the battery under test. Furthermore, since the individual battery cells are not covered, the cuts allow for air cooling. Preferably, the cuts also serve to secure the temperature measuring device to the battery. More preferably, the cuts are arranged such that the battery cell holders of the individual battery cells protrude through the cuts, allowing the circuit board to be directly positioned on the individual battery cells for direct thermal contact.

[0017] In the battery according to the invention, each of the second insulating regions is thermally connected to at least one battery cell connector of the battery.

[0018] The battery according to the invention preferably comprises multiple rows of individual battery cells arranged adjacent to each other. For example, the individual battery cells may be arranged in a matrix of N individual battery cells in M ​​rows of the battery, where N and M are natural numbers greater than or equal to 2.

[0019] Preferably, the battery includes multiple temperature measuring devices, with one temperature measuring device positioned for every two rows of individual battery cells. Specifically, each of the multiple temperature sensors monitors the temperature of two to four individual battery cells.

[0020] Preferably, the battery has electronic equipment for evaluating the measurement signals from the temperature sensor. For this purpose, the electronic equipment is connected to the multi-pole terminals of at least one temperature measuring device via a multi-pole cable. The individual temperatures measured by the temperature sensor are preferably determined proportionally. In particular, this means that the ratios of the measurement signals to each other are determined, for example, based on which deviations from expected values ​​or average values, or cases exceeding limits, can be determined. Attached Figure Description

[0021] Further advantageous extensions will now be described in more detail with reference to exemplary embodiments shown in the accompanying drawings; however, the invention is not limited thereto.

[0022] In the picture:

[0023] Figure 1 Figure 1 A cross-sectional view of an exemplary embodiment of a battery having a temperature measuring device according to the present invention is shown.

[0024] Figure 2 Figure 2 a shows a top view of the temperature measuring device according to the present invention. Figure 2 b shows the corresponding bottom view.

[0025] Figure 3 Figure 3 An exemplary circuit diagram of a temperature measuring device according to the present invention is shown.

[0026] Figure 4 Figure 4 a and Figure 4 b illustrates two different exemplary embodiments of the temperature measuring device according to the present invention.

[0027] Figure 5 Figure 5 A cross-sectional view of another exemplary embodiment of the temperature measuring device with a compression belt according to the present invention is shown. Detailed Implementation

[0028] In the following description of preferred embodiments of the present invention, the same reference numerals denote the same or similar parts.

[0029] Figure 1 A cross-sectional view of an exemplary embodiment of a battery 20 having a temperature measuring device 10 according to the present invention is shown. The battery 20 includes a plurality of individual battery cells 21 arranged in a row. The plurality of individual battery cells 21 are connected in pairs to battery cell connectors 22 via welding or fusion points 24 and are connected in series. Battery cell holders 23 are arranged between the individual battery cells 21 and mechanically support the individual battery cells 21. The battery 20 according to the present invention may have multiple rows of individual battery cells 21. In particular, the battery 20 may be constructed as a matrix having M rows, each row having N individual battery cells 21, where M and N are natural numbers between 10 and 20, for example, particularly 16.

[0030] Figure 1In the center, two individual battery cells 21 are shown, with the positive electrode of the left cell 21 located at the top and the positive electrode of the right cell 21 located at the bottom. The two individual battery cells 21 are connected to the upper battery cell connector 22 via soldering or fusion points 24, thus forming a series connection. More individual battery cells 21 are indicated by dashed lines to the right and left of the centrally shown cell 21, to show that only a portion of the multiple individual battery cells 21 are shown.

[0031] A temperature measuring device 10 is disposed on the battery 20. The temperature measuring device 10 includes a multilayer circuit board 1 having an upper conductive layer 1a and a lower conductive layer 1b as a carrier element. The circuit board 1 is made of a heat-insulating material, such as plastic or fiber-reinforced plastic or commercial FR4 (a type of flame-retardant and fire-retardant composite material composed of epoxy resin and glass fiber fabric, "Flame Retardant 4"), and has a thickness of one to several millimeters. The conductive layers 1a and 1b typically have a thickness of tens to hundreds of micrometers, for example 35 μm, and are made of a conductive material such as copper.

[0032] Multiple temperature sensors 2 are arranged on the circuit board 1, each of which generates a temperature-related measurement signal. Figure 1 The temperature sensor 2 shown in the center is disposed on a first insulating region 5a of the upper conductive layer 1a. This insulating region 5a is separated from the rest of the upper conductive layer 1a by an electrical insulator 6. The temperature sensor 2 is disposed directly on the first insulating region 5a, such that the temperature sensor 2 measures the temperature of the first insulating region 5a.

[0033] A second insulating region 5b, serving as the thermal contact surface, is disposed below the first insulating region 5a and on the underside of the circuit board 1. The thermal contact surface is located directly on the battery cell connector 22 of the battery 20. The spacing in the attached figures is for better illustration only. Thermal paste can be used to improve thermal conduction between the battery cell connector 22 and the thermal contact surface.

[0034] The first insulating region 5a is thermally connected to the lower second insulating region 5b via three through-connections 4, so that the heat output from the individual battery cell 21 to the battery cell connector 22 is directly transferred to the first insulating region 5a through the thermal contact surface 5b and the through-connections 4, and thus to the temperature sensor 2. Therefore, by placing the temperature sensor 2 on the upper side of the circuit board 1, the temperature of the lower individual battery cell 21 can be accurately measured.

[0035] Similar to conductive layers 1a and 1b, the through-connection 4 can be made of copper. Depending on purity, copper has a relatively high thermal conductivity of approximately 240 to 400 W / (m K). On the other hand, plastic has a very low thermal conductivity of less than 1 W / (m K). Therefore, heat can be transferred directly from the thermal contact surface 5b (measuring point) to the temperature sensor 2 without heat loss in the circuit board 1. Furthermore, copper has a relatively low heat capacity of 0.382 kJ / (kg K), and therefore, with high thermal conductivity, it has a correspondingly high thermal diffusivity α. Thermal diffusivity α is the ratio of thermal conductivity λ to the product of heat capacity c and density ρ:

[0036]

[0037] The thermal diffusivity α quantifies the change in the spatial distribution of temperature over time due to heat conduction caused by the temperature gradient. This means that due to the high thermal diffusivity of the material between temperature sensor 2 and the thermal contact surface 5b, temperature can be measured quickly and with almost no loss.

[0038] Of course, any other suitable material can be used instead of copper.

[0039] like Figure 1 As shown, temperature sensor 2 is connected to circuit board 1 via pad 7. Pad 7 also makes electrical contact with conductor tracks 3a and 3b, which are connected to multi-terminal 11 for reading measurement signals (see...). Figure 2 ).

[0040] In an embodiment not shown, each temperature sensor 2 may be surrounded by a thermally conductive sheath, which is thermally connected to the corresponding first insulating region 5a. This thermally conductive sheath improves heat transfer from the first insulating region 5a to the temperature sensor 2. Specifically, heat is evenly distributed across the entire periphery of the temperature sensor 2, thereby enabling more accurate temperature measurement.

[0041] Figure 2 a shows a top view of the temperature measuring device 10 according to the present invention. Figure 2 b shows the corresponding top view. Only the middle portion of the temperature measuring device 10 is shown in each case, allowing the four temperature sensors 2 to be seen. The temperature measuring device 10 extends significantly further to the left and right than depicted in the illustration. The exemplary temperature measuring device 10 includes a total of eight temperature sensors 2.

[0042] like Figure 2As shown, the temperature measuring device 10 includes a plurality of fixing devices 12 for securing the circuit board 1 to the battery 20. The fixing devices 12 are configured, for example, as holes on the circuit board 1 located directly next to the temperature sensor 2, so that the temperature measuring device 10 can be screwed onto the battery 20, wherein a firm and direct contact is ensured between the thermal contact surface 5b and the battery cell connector 22 of the battery 20.

[0043] Figure 2 The center of electrode 'a' shows a multi-terminal 11 for reading measurement signals. In the exemplary embodiment shown, there is a ten-terminal 11 with eight signal terminals and two ground terminals. Each signal terminal is connected to a first terminal of the temperature sensor 2 via a separate first conductor rail 3a on the upper conductive layer 1a. Each ground terminal is connected to a second terminal of the temperature sensor 2 via a common second conductor rail 3b.

[0044] Temperature measuring device 10 can be connected to electronic equipment for evaluating the measurement signals of temperature sensor 2 via multi-pole terminals 11 and corresponding multi-pole cables. According to an exemplary embodiment, the individual temperatures measured by temperature sensor 2 are determined proportionally by the electronic equipment. This means, in particular, determining the proportions between the measurement signals, where, for example, deviations from desired or average values, or cases exceeding limits, can be identified.

[0045] The circuit board 1 also has multiple rectangular cutouts 14. The cutouts 14 reduce the total surface area and total mass of the temperature measuring device 10. As a result, the total heat capacity of the temperature measuring device 10 is reduced, and since the temperature measuring device 10 absorbs less heat from the battery under test 20, the accuracy of the measurement is improved.

[0046] Furthermore, the cut 14 allows air to be supplied, thereby cooling the individual battery cell 21. Additionally, the cut 14 serves to secure the temperature measuring device 10 to the battery 20. Moreover, the cut can be arranged such that the battery cell holder 23 of the individual battery cell protrudes through the cut 14, allowing the circuit board 1 to be directly positioned on the battery cell connector 22 of the individual battery cell 21 for direct thermal contact. Furthermore, the circuit board 1 has a locking hole 13 for securing the temperature measuring device 10 to the battery 20.

[0047] Figure 3 An exemplary circuit diagram of a temperature measuring device 10 is shown. Eight signal lines 3a extend from a ten-terminal terminal 11 to eight temperature sensors 2. Two ground lines 3b are also provided for grounding the temperature sensors 2. The temperature sensors 2 are configured as NTC thermistors, whose resistance value can be determined as the measured temperature value.

[0048] Figure 4 a and Figure 4 b each in a similar manner Figure 2 A top view of a shows a portion of the temperature measuring device 10, with each case showing a portion surrounding the temperature sensor 2. For clarity, Figure 2 The details shown in a Figure 4 The terms 3a and 3b, such as conductor orbitals, are omitted.

[0049] Figure 4 a and Figure 4 b illustrates different exemplary embodiments of two through-connecting portions 4 with different arrangements. Figure 4 In embodiment a, the three through-connecting parts 4 are directly arranged below the temperature sensor 2. Therefore, this embodiment basically corresponds to Figure 1 The example shown. The through-connection 4 can be, for example, a through-connection filled with copper. However, the through-connection 4 can also be formed as a hole whose walls are covered only by a conductive layer, for example, made of copper. In each case, a through-hole is retained, through which air can pass. The first insulating region 5a is shown as a dashed area. Figure 4 In a and 4b.

[0050] Figure 4 b illustrates an optional exemplary embodiment in which the through-connection 4 is not arranged below the temperature sensor 2 but rather beside it. Furthermore, a third insulating region 5c is arranged beside the temperature sensor 2, and its surface substantially corresponds to the second insulating region 5b on the underside of the temperature measuring device 10 (see [link to example 1]). Figure 2 b). For example, the third insulating region 5c can be made of copper. In this embodiment, the through-connection 4 can have a large diameter. Figure 4 In section b, four through-connecting parts 4 are shown as an example. Since the available area is large, more than four through-connecting parts 4 may also be provided.

[0051] Similar to Figure 4 In an example of a, the through-connection 4 of an optional exemplary embodiment may be a through-connection filled with copper or a hole whose walls are only covered with a conductive layer made of, for example, copper. In each case, a through-hole is retained through which air can flow. Due to... Figure 4 Compared to a larger diameter, the through-hole can be larger, thus improving air exchange. Furthermore, plating the through-hole 4 can improve thermal conductivity. Additionally, capillary effects can be reduced, thus preventing condensation within the through-hole.

[0052] The third insulating region 5c is particularly effective at absorbing heat from the second insulating region 5b and transferring it to the temperature sensor 2 through its connection with the first insulating region 5a. Therefore, improved heat transfer from the lower to the upper side of the temperature measuring device 10 can be achieved using the temperature sensor 2, thereby improving temperature measurement.

[0053] Figure 5Another exemplary embodiment of the battery 20 according to the present invention is shown, wherein, with Figure 1 Unlike the exemplary embodiment, the compression tape 30 is arranged on the temperature measuring device 10. In particular, the compression tape 30 can be attached to the circuit board 1 of the temperature measuring device 10.

[0054] The compression tape 30 is electrically insulating, thermally insulating, and sealing. For example, it can be a pre-compressed impregnated foam sealant tape, such as a polyurethane-based foam sealant tape. Alternatively, it can be a compression tape made of, for example, rubber. It can be mechanically deformed to conform to the surface of the temperature measuring device 10 and will expand upon compression. The compression tape 30 can be mechanically pressed against the circuit board 1 of the temperature measuring device 10 by the housing cover of the battery 20, thus allowing it to adhere firmly to the circuit board 1 without the need for adhesives.

[0055] The compression band 30 can advantageously cover the temperature measuring device 10 in an airtight manner, thereby preventing the undesirable formation of condensation on the temperature measuring device 10. In addition, the compression band 10 acts as insulation against the ambient air, which means that the accuracy of temperature measurement can be improved because the temperature of the circuit board 1 is no longer (or at least minimally) affected by the ambient air.

[0056] The features disclosed in the foregoing description, claims and drawings may be important for the implementation of the invention individually and in any combination in various embodiments.

Claims

1. A battery (20) comprising a plurality of individual battery cells (21), characterized in that, The battery (20) has at least one temperature measuring device (10), wherein the at least one temperature measuring device (10) includes: A multilayer circuit board (1) having an upper conductive layer (1a) and a lower conductive layer (1b) as a carrier element; Multiple temperature sensors (2), each temperature sensor (2) is configured to generate a temperature-related measurement signal; The multi-ended sub-unit (11) used to read the measurement signal, wherein: Each of the plurality of temperature sensors (2) is arranged in a first insulating region (5a) of the upper conductive layer (1a), which is separated from the rest of the upper conductive layer (1a) by electrical insulation (6). For each temperature sensor (2), the lower conductive layer (1b) has a second insulating region (5b) as a thermal contact surface; Each first insulating region (5a) is thermally connected to a corresponding second insulating region (5b) via at least one through-connection (4). Each of the second insulating regions (5b) is thermally connected to at least one battery cell connector (22) of the battery (20).

2. The battery (20) according to claim 1, characterized in that, The multi-extreme sub (11) includes: Multiple signal electrodes, each electrically connected to one of the multiple temperature sensors (2) via a separate conductor track (3a) in the upper conductive layer (1a); and At least one grounding electrode is electrically connected to each of the plurality of temperature sensors (2) via at least one conductor rail (3b).

3. The battery (20) according to claim 1 or 2, characterized in that, Each first insulating region (5a) is thermally connected to the corresponding second insulating region (5b) through multiple through-connection portions (4).

4. The battery (20) according to claim 1 or 2, characterized in that, The circuit board (1) is made of heat-insulating material; and / or The temperature measuring device (10) also includes a plurality of fixing devices (12) for fixing the circuit board (1) to the battery (20).

5. The battery (20) according to claim 1 or 2, characterized in that, Each of the temperature sensors (2) is surrounded by a thermally conductive sheath that is thermally connected to the corresponding first insulating region (5a).

6. The battery (20) according to claim 1 or 2, characterized in that, The circuit board (1) has multiple cutouts (14).

7. The battery (20) according to claim 1, characterized in that, The battery (20) comprises multiple rows of individual battery cells (21) arranged adjacent to each other; and Each of the multiple temperature sensors (2) is configured to measure the temperature of multiple individual battery cells (21) from adjacent rows.

8. The battery (20) according to claim 1 or 7, characterized in that, The temperatures measured by the temperature sensor (2) are determined proportionally.

9. The battery (20) according to claim 1, 2, or 7, characterized in that, A compression belt (30) is arranged on the upper side of the temperature measuring device (10).

10. The battery (20) according to claim 1, 2, or 7, characterized in that, Multiple through-connection portions (4) are arranged between the third insulating region (5c) and the second insulating region (5b) of the upper conductive layer (1a), wherein the third insulating region (5c) is arranged in an offset manner next to the temperature sensor (2).

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