Battery including integrated temperature probe

Abstract

A battery includes a plurality of stacked cells. Each cell includes an anode layer and a cathode layer separated by a permeable separator. At least one temperature probe structure is disposed on the permeable separator between the anode layer and the cathode layer of a first cell of the stacked cells. The temperature probe structure includes at least a first material partially coating the permeable separator and a second material partially coating the permeable separator. The first material overlaps the second material at the overlap region. The first sensor output terminal is connected to the first material and the second sensor terminal is connected to the second material. A voltage difference between the first sensor output terminal and the second sensor output terminal corresponds to an average temperature of the overlapping region.

Description

Technical Field

[0001] The present disclosure relates to battery pack temperature monitoring systems, and more particularly to integrated temperature probes for monitoring battery pack temperature monitoring systems. Background Art

[0002] Vehicles, including electric vehicles and hybrid electric vehicles, include power storage and distribution systems configured to store power received during charging operations and distribute the stored power to vehicle systems when the vehicle is in operation. One method of storing power is via stacked battery cells.

[0003] Charging and discharging operations, as well as ambient temperature fluctuations and heat from vehicle systems can affect the temperature of the battery cells. The temperature of the battery cells can affect the efficiency of the battery. In addition, unexpected temperature changes can indicate a malfunction or other undesirable operation.

[0004] Therefore, it is desirable to provide an efficient and targeted system for monitoring battery temperature within a battery cell stack. Summary of the invention

[0005] In an exemplary embodiment, the battery includes a plurality of stacked cells, each cell including an anode layer and a cathode layer separated by a permeable separator, at least one temperature probe structure is disposed on the permeable separator between the anode layer and the cathode layer of a first cell of the stacked cells, the temperature probe structure includes at least a first material partially coated with the permeable separator and a second material partially coated with the permeable separator, the first material overlaps the second material in an overlap region, a first sensor output terminal connected to the first material and a second sensor terminal connected to the second material, and wherein a voltage difference between the first sensor output terminal and the second sensor output terminal corresponds to an average temperature of the overlap region.

[0006] In addition to one or more features described herein, the battery includes a plurality of temperature sensors, each temperature sensor of the plurality of temperature sensors being disposed in a different battery in the plurality of stacked cells.

[0007] In addition to one or more features described herein, the overlap region of each temperature sensor is at the same coordinate location within each battery cell.

[0008] In addition to one or more features described herein, the overlap region of each temperature sensor is at different coordinate locations within each battery cell.

[0009] In addition to one or more features described herein, the first material has a coating thickness in a range of 50 nm to 500 nm, and the second material has a coating thickness in a range of 50 nm to 500 nm.

[0010] In addition to one or more features described herein, the first material is one of Cu and Cu-Ni alloys, Ni-Al alloys, Ni-Cr alloys, Fe, Ni-Si alloys, Pt, Pd, Pd-rare earths, and ceramic materials, and the second material is another of Cu and Cu-Ni alloys, Ni-Al alloys, Ni-Cr alloys, Fe, Ni-Si alloys, Pt, Pd, Pd-rare earths, and ceramic materials.

[0011] In addition to one or more features described herein, a metal foil contacts one of a first material and a second material, wherein the metal foil is embedded and disposed in the one of the first material and the second material, and wherein the metal foil is a reference electrode.

[0012] In another exemplary embodiment, a vehicle includes a propulsion system, the propulsion system including at least one electric motor, a battery system connected to the propulsion system via a power distribution system, the battery system including at least one group of multiple stacked battery cells, each of the multiple stacked battery cells including an anode layer and a cathode layer separated by a permeable separator, at least one temperature probe structure disposed on the permeable separator between the anode layer and the cathode layer of a first battery of the stacked battery cells, the temperature probe structure including at least a first material that partially coats the permeable separator and a second material that partially coats the permeable separator, the first material overlapping the second material at an overlap region, a first sensor output terminal connected to the first material and a second sensor terminal connected to the second material, and wherein a voltage difference between the first sensor output terminal and the second sensor output terminal corresponds to an average temperature of the overlap region, and a controller including at least one input connected to the first terminal and the second terminal, wherein the controller is configured to convert the voltage difference across the first terminal and the second terminal into a temperature.

[0013] In addition to one or more features described herein, the at least one temperature probe structure includes a plurality of temperature probe structures, each of the plurality of temperature probe structures being disposed in a different battery cell among the plurality of stacked battery cells, and wherein the controller is configured to determine a temperature map of the plurality of stacked battery cells.

[0014] In addition to one or more features described herein, the overlap region of each temperature probe structure is at the same coordinate location as each other overlap region within the respective battery, and the temperature map of the plurality of stacked cells defines a temperature gradient along the plurality of stacked cells.

[0015] In addition to one or more features described herein, the overlap region of each temperature probe structure is at a different coordinate location within the respective battery than each other overlap region, and the temperature map of the plurality of stacked cells defines a distributed temperature map.

[0016] In addition to one or more features described herein, the first material has a coating thickness in a range of 50 nm to 500 nm, and the second material has a coating thickness in a range of 50 nm to 500 nm.

[0017] In addition to one or more features described herein, the first material is one of Cu and Cu-Ni alloys, Ni-Al alloys, Ni-Cr alloys, Fe, Ni-Si alloys, Pt, Pd, Pd-rare earths, and ceramic materials, and the second material is another of Cu and Cu-Ni alloys, Ni-Al alloys, Ni-Cr alloys, Fe, Ni-Si alloys, Pt, Pd, Pd-rare earths, and ceramic materials.

[0018] In addition to one or more features described herein, a metal foil contacts one of a first material and a second material, wherein the metal foil is embedded and disposed in the one of the first material and the second material, and wherein the metal foil is a reference electrode.

[0019] In yet another exemplary embodiment, a method for determining a temperature of a battery cell stack includes providing at least a first voltage potential difference between a first output terminal and a second output terminal to a controller, and converting at least the first voltage potential difference to a temperature using the controller, wherein the first sensor terminal and the second sensor output are components of a temperature probe structure disposed on a permeable separator between an anode layer and a cathode layer of a first battery cell of a stacked battery cell. At least one temperature probe structure disposed on the permeable separator between an anode layer and a cathode layer of a first battery cell of the stacked battery cell, the temperature probe structure comprising at least a first material partially coating the permeable separator and a second material partially coating the permeable separator, the first material overlapping the second material in an overlapping region, the first sensor output terminal connected to the first material, and the second sensor terminal connected to the second material.

[0020] In addition to one or more features described herein, providing at least a first voltage potential difference between a first sensor output terminal and a second sensor output terminal to the controller includes providing a plurality of voltage potential differences to the controller and converting each of the plurality of voltage potential differences to a plurality of temperatures, each provided voltage potential difference corresponding to a different temperature sensor within the stacked battery cells.

[0021] In addition to one or more features described herein, the method includes combining the plurality of temperatures into a gradient measurement of the battery temperature.

[0022] In addition to one or more features described herein, the method also includes combining the plurality of temperatures into a point cloud measurement of the cell stack temperature.

[0023] In addition to one or more features described herein, the first material has a coating thickness in a range of 50 nm to 500 nm, and the second material has a coating thickness in a range of 50 nm to 500 nm.

[0024] In addition to one or more features described herein, the first material is one of Cu and Cu-Ni alloys, Ni-Al alloys, Ni-Cr alloys, Fe, Ni-Si alloys, Pt, Pd, Pd-rare earths, and ceramic materials, and the second material is another of Cu and Cu-Ni alloys, Ni-Al alloys, Ni-Cr alloys, Fe, Ni-Si alloys, Pt, Pd, Pd-rare earths, and ceramic materials.

[0025] The above features and advantages and other features and advantages of the present disclosure are apparent from the following detailed description when taken in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Other features, advantages and details appear, by way of example only, from the following detailed description, which refers to the accompanying drawings, in which:

[0027] Figure 1 is a vehicle that includes an electric propulsion motor;

[0028] Figure 2 is a schematic diagram of a battery cell according to one embodiment;

[0029] Figure 3 is a schematic diagram of a battery cell stack according to one embodiment;

[0030] Figure 4 is a detailed schematic diagram of a temperature probe separator for a battery cell;

[0031] Figure 5A is a schematic diagram of a temperature probe separator according to an example;

[0032] Figure 5B is a schematic diagram of a temperature probe separator according to another example;

[0033] Figure 5C is a schematic diagram of a temperature probe separator according to another example; and

[0034] Figure 5D is a schematic diagram of a temperature probe separator according to another example. DETAILED DESCRIPTION

[0035] The following description is merely exemplary in nature and is not intended to limit the present disclosure, its application or use. It should be understood that throughout the drawings, corresponding reference numerals represent identical or corresponding components and features. As used herein, the term module refers to a processing circuit, which may include an application-specific integrated circuit (ASIC), an electronic circuit, a processor (shared, dedicated or group) and memory that executes one or more software or firmware programs, a combinational logic circuit, and / or other suitable components that provide the described functionality. As used herein, the term controller refers to any computerized control system, including a dedicated control system, a general vehicle controller, a control program distributed on multiple systems, or any similar control architecture.

[0036] According to an exemplary embodiment, a battery system for a vehicle includes at least one battery including a set of stacked battery cells. A separator-like temperature probe is placed between electrode layers of a given cell without changing the cell operation. The temperature probe is capable of measuring the temperature within the cell stack and can include targeted measurements of specific locations within the cell stack.

[0037] The temperature probe has a double-layer thin film coating with two selective materials on one side of the separator. The two selective materials overlap in the overlap area, and the voltage potential difference between the two materials measured across the output terminals connected to each material is related to the temperature. The specific relationship and conversion between the voltage potential difference and the cell temperature depends on the known relationship between the selective materials used to form the probe. A controller is connected to the output terminals, and each output terminal contacts only one of the selective materials. The voltage potential difference across the terminals is regressed using the known relationship to find the average temperature across the overlap area. The size and location of the overlap area on the separator provides an accurate target for the internal sensor measurement.

[0038] The temperature probe (a combination of a material layer and a separator layer provided with the material) is porous and permeable and is placed in the cell stack and can monitor the temperature within the cell stack without interfering with the cell operation. This sensor design provides the flexibility of allowing measurements to be made at various locations within the stack, and the measurements do not rely on external probes or estimates.

[0039] Continuing with the general system referenced above, Figure 1An embodiment of a motor vehicle 10 is shown that includes a battery system controller 24 that is configured to control a battery system. The vehicle 10 includes a vehicle body 12 that at least partially defines a passenger compartment 14. The vehicle body 12 also supports various vehicle subsystems, including a propulsion system 16, a battery system 22, other subsystems for supporting the functions of the propulsion system 16 and other vehicle components, such as a braking subsystem, a suspension system, a steering subsystem, a fuel injection subsystem, an exhaust subsystem, etc.

[0040] The vehicle 10 may be an internal combustion vehicle, an electric vehicle (EV), or a hybrid vehicle. In one embodiment, the vehicle 10 is a hybrid vehicle that includes an internal combustion engine system 18 and at least one electric motor assembly. For example, the propulsion system 16 includes a first electric motor 20 and a second electric motor 21. The motors 20 and 21 may be configured to drive wheels 23 on opposite sides of the vehicle 10. Any number of motors positioned at various additional locations around the vehicle 10 may be used to provide mechanical rotation to corresponding systems and subsystems.

[0041] The battery system 22 can be electrically connected to the motors 20 and 21 and / or other components, such as vehicle electronics. The battery system 22 can be configured as a rechargeable energy storage system (RESS) and include a plurality of battery cells divided into a plurality of sections. The battery system controller 24 is included in the battery system 22 and controls the charging and discharging functions of the batteries within the battery system 22. In an alternative configuration, the battery system controller 24 can be a general vehicle controller that is remote from the battery system 22 and is configured to control a plurality of systems and / or subsystems. The general vehicle controller can be located anywhere within the vehicle 10. In another alternative, the battery system controller 24 can be a distributed control system that includes a plurality of coordinated controllers throughout the vehicle 10, including controllers within the battery system 22 and controllers remote from the battery system 22.

[0042] In one embodiment, the battery system 22 includes one or more battery packs 28. The battery pack 28 includes a plurality of different battery cells arranged in a stack. Figure 1 In the exemplary system of , power distribution bus 29 is shown in simplified form and provides power to propulsion system 16 through inverter 26 .

[0043] Continue to refer Figure 1 , Figure 2A simplified exemplary battery cell 100 such as may be used in the battery system 24 is shown. The exemplary cell 100 includes an anode layer 110 and a cathode layer 120. Positioned between the anode layer 110 and the cathode layer 120 is a separator layer 130. The separator layer 130 is an electrically insulating material and includes a thermal probe structure including a first coating 162 disposed on a first side of the separator layer 130, a second coating 166 disposed on a first side of the separator layer 130, an overlap region 170 where the first coating 162 and the second coating 166 overlap each other, a tab 131 extending from the separator layer 130 and including portions of the first coating 162 and the second coating 166, and a pair of leads 132, 134 extending from the first coating 162 and the second coating 164 (respectively), the leads 132, 134 being supported by the tab 131. In some examples, the spacer layer 130 can include another spacer layer on top of the thermal probe structure, wherein the second spacer layer is substantially the same as the spacer layer 130, and the spacer layer 130 coating material is between the spacer layer 130 and the second spacer layer. The spacer layer 130 is sufficiently thin (in the range of 10 μm to 50 μm), permeable and porous. The thickness of each coating material 162, 166 is in the range of 50 nm to 500 nm. The tab 131 extends beyond the circumferential edge of the spacer layer 130. In an alternative example (see Figure 5B , Figure 5C , Figure 5D ), each terminal 132, 134 can be on a separate tab, thereby creating two distinct tabs, each protruding beyond the circumferential edge of the separator layer 130. Although actual embodiments of the separator 130, the first coating 162, and the second coating 166 include a third dimension of vertical thickness, for ease of explanation, the battery cell 100 can be considered to be a planar structure defined by an XY coordinate grid, where the circumferential edge is the edge in the XY plane.

[0044] Each battery in the battery system 22 is composed of a plurality of battery cells 100 . Figure 3 An example stack of three battery cells 200 is shown, wherein each battery cell 200 includes an anode layer 210 and a cathode layer 220, as shown in FIG. Figure 2 The battery cells 200 are stacked such that the cathode layer 220 of one battery cell 200 is adjacent to the anode layer 210 of the next battery cell 200, and another separator 238 is located between the battery cells 200. In the example shown, the separator layer 238 between the battery cells 200 does not include a temperature probe structure. A separator layer 230 is included in each battery cell 200, and the separator layer 230 includes a temperature probe structure for Figure 2 The terminals 232, 234 are arranged in the manner described. In alternative embodiments, the separator layer 230 may be a supplement to a conventional separator layer.

[0045] Terminals 232, 234 and corresponding temperature probe structure ( Figure 2 ) may be included in each battery cell 200, it being understood that actual implementations of the battery system 24 may include any number of cells 200, wherein a subset of the cells 200 include a temperature probe structure. In such examples, the number of cells 200 that include a temperature probe structure is typically limited to the number of inputs available in the corresponding controller.

[0046] Figure 4 A more detailed example of a temperature probe structure is schematically shown, such as may be seen in Figure 2 and Figure 3 A more detailed example of a temperature probe structure used in a battery cell 100, 200, including a top view and a partial cross-sectional view along section AA. The separator 330 includes a porous permeable layer 332, which serves as a separator 130, 230 between the cathode layer 120, 220 and the anode layer 110, 210 of the corresponding battery cell 100, 300. Two tabs 342, 344 extend outwardly from the separator layer 332, and a corresponding output terminal 352, 354 is mounted to each tab 342, 344. Each terminal 352, 354 is connected to the input of a controller 356, and the controller 356 measures the voltage potential difference between the terminals 352, 354 and converts the difference into a temperature value.

[0047] Disposed on the separator 330 is a first coating 362 covering a first region 364 and a second coating 366 covering a second region 368. The first region 364 and the second region include a common overlap region 370, where the coatings 362, 366 overlap and contact each other. The first coating 362 extends onto the first tab 342, and the second coating 366 extends onto the second tab 344. The terminals 352, 354 on each tab 342, 344 contact the corresponding coating 262, 266. The coatings 362, 366 are different materials, and in one example, are selected from one of the following list: Cu and Cu-Ni alloys, Ni-Al alloys, Ni-Cr alloys, Fe, Ni-Si alloys, Pt, Pd, Pd-rare earths, and ceramic-based materials. The thickness 380 of each coating is in the range of 50nm to 500nm. By using a thickness in the range of 50 nm to 500 nm, the coatings 362, 366 do not reduce the porosity or permeability of the separator 330, and therefore do not impair the energy storage and discharge functions of the battery cells 100, 200. In some examples, one or both of the coatings 362, 366 may include a relatively small metal foil patch 301, such as a lithium metal foil, deposited on or embedded in one of the coatings 362, 366. The metal foil patch 301 is connected to a lead 303 supported on one of the tabs 342, 344 and serves as a reference electrode to provide the local voltage of the cathode layer 220 and the anode layer 210, respectively, to the controller in any known manner.

[0048] Due to the different materials of each layer 362, 366, there is a voltage potential difference between the two terminals 352, 354. The voltage potential difference depends on the average temperature over the overlap region 370. The controller 356 converts the voltage potential difference into a temperature reading at the overlap region 370 and provides the temperature reading to any other control program, controller, and / or vehicle system that may need or use this information.

[0049] It should be understood that since the voltage potential difference is the average temperature over the overlap region 370 , different temperature measurements may be made depending on the location of the overlap region 370 within the battery cells 100 , 200 . Figure 5A , Figure 5B , Figure 5C and Figure 5D The examples of FIG. 37 show exemplary, non-limiting variations in the locations and sizes (as a percentage of the divider 330 ) covered by the overlap region 370 according to some examples.

[0050] Figure 5A An example is shown where the terminals 352, 354 are disposed on a common tab 342 / 344, where each terminal 352, 354 contacts only one of the coatings. Figure 5AIn the example of FIG. 1 , the overlap region 370 covers all of the dividers 330 and provides a Figure 5A The average temperature reading of the entire battery cell 100, 200 of the separator 330. Figure 5B Shown with Figure 5A A similar example, however, each of the terminals 352 , 354 is mounted to a different tab 342 , 344 , and the respective coating covers the entire tab 342 , 344 .

[0051] Figure 5C An example with two tabs 342, 344 is provided, where each tab 342, 344 supports one terminal 352, 354. The coatings 362, 366 combined cover less than 50% of the separator 330, with each layer 362, 366 covering less than 30% of the surface. The overlap region 370 is provided at the center point of the separator 330, and a point temperature reading is generated at the center of the separator 330. It should also be understood that similar point readings can be generated in a similar configuration by positioning the overlap region 370 at any point in the battery cell 100, 200 where a temperature reading is desired.

[0052] In some examples, including multiple separators 330 within the battery system 24 or including multiple separators 330 within a single battery cell 100 , 200 (with overlapping areas 370 at different locations) is used to provide a point map of temperature changes across the battery cell 100 , 200 or battery system 24 .

[0053] Figure 5D An example is shown where the overlap region 370 extends along the entire edge of the divider 330 and is otherwise similar to the Figure 5C The examples of are constructed similarly.

[0054] It should be understood that in some examples, a single battery system 24 or a single battery cell 100, 200 may utilize all or some of the variations shown, and that these variations are not mutually exclusive within a single battery. Figure 5A , Figure 5B , Figure 5C and Figure 5D Combinations of multiple different separators similar to the separators described in can be used in conjunction with each other to create a three-dimensional grid or array of temperature readings that can be converted by a controller into gradient measurements across a single cell 100, 200 or an entire cell stack.

[0055] The term "one" does not indicate a limitation of quantity, but rather indicates the presence of at least one of the referenced items. Unless the context clearly indicates otherwise, the term "or" means "and / or". References to "aspects" throughout the specification mean that a particular element (e.g., a feature, structure, step, or characteristic) described in conjunction with that aspect is included in at least one aspect described herein, and may or may not be present in other aspects. In addition, it should be understood that the described elements may be combined in any suitable manner in the various aspects.

[0056] When an element such as a layer, film, region, or substrate is referred to as being "on" another element, it can be directly on the other element or intervening elements may also be present. In contrast, when an element is referred to as being "directly on" another element, there are no intervening elements present.

[0057] Unless otherwise indicated herein, all test standards are the most current standards in effect as of the filing date of this application or, if priority is claimed, the filing date of the earliest priority application in which the test standards appear.

[0058] Unless defined otherwise, technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs.

[0059] Although the above disclosure has been described with reference to exemplary embodiments, it will be appreciated by those skilled in the art that various changes may be made and equivalents may be substituted for its elements without departing from its scope. In addition, many modifications may be made to adapt specific circumstances or materials to the teachings of the disclosure without departing from the basic scope of the disclosure. Therefore, it is intended that the disclosure is not limited to the specific embodiments disclosed, but will include all embodiments falling within its scope.

Claims

1. A battery comprising: a plurality of stacked battery cells, each battery cell comprising an anode layer and a cathode layer separated by a permeable separator; at least one temperature probe structure disposed on a permeable separator between an anode layer and a cathode layer of a first cell of the stacked cells, the temperature probe structure comprising at least a first material partially coating the permeable separator and a second material partially coating the permeable separator, the first material overlapping the second material in an overlap region, a first sensor output terminal connected to the first material and a second sensor terminal connected to the second material; as well as The voltage difference between the first sensor output terminal and the second sensor output terminal corresponds to an average temperature of the overlapping area.

2. The battery according to claim 1, wherein The battery includes a plurality of temperature sensors, each of the plurality of temperature sensors being disposed in a different cell among the plurality of stacked cells. 3 . The battery according to claim 2 , wherein the overlapping area of ​​each temperature sensor is at the same coordinate position within each battery cell. 4 . The battery according to claim 2 , wherein the overlapping region of each temperature sensor is at a different coordinate position within each battery cell. 5 . The battery according to claim 1 , wherein the first material has a coating thickness ranging from 50 nm to 500 nm, and the second material has a coating thickness ranging from 50 nm to 500 nm.

6. The battery according to claim 1, wherein the first material is one of Cu and Cu-Ni alloy, Ni-Al alloy, Ni-Cr alloy, Fe, Ni-Si alloy, Pt, Pd, Pd-rare earth and ceramic material, and the second material is another of Cu and Cu-Ni alloy, Ni-Al alloy, Ni-Cr alloy, Fe, Ni-Si alloy, Pt, Pd, Pd-rare earth and ceramic material.

7. The battery of claim 1, further comprising a metal foil contacting one of the first material and the second material, wherein the metal foil is embedded and disposed in the one of the first material and the second material, and wherein the metal foil is a reference electrode.

8. A vehicle comprising: a propulsion system, the propulsion system comprising at least one electric motor; A battery system connected to the propulsion system via a power distribution system, the battery system comprising at least one group of multiple stacked battery cells according to any one of claims 1-7.

9. A method for determining the temperature of a battery cell stack, comprising: Provide at least a first voltage potential difference between a first output terminal and a second output terminal to a controller, and convert the at least first voltage potential difference into a temperature using the controller, wherein the first sensor terminal and the second sensor output are components of a temperature probe structure, the temperature probe structure is disposed on a permeable separator between an anode layer and a cathode layer of a first battery cell of the stacked battery cells, at least one temperature probe structure is disposed on the permeable separator between an anode layer and a cathode layer of a first battery cell of the stacked battery cells, the temperature probe structure comprises at least a first material partially coated on the permeable separator and a second material partially coated on the permeable separator, the first material overlaps with the second material in an overlapping area, the first sensor output terminal is connected to the first material, and the second sensor terminal is connected to the second material.

10. The method according to claim 9, wherein: Providing at least a first voltage potential difference between the first sensor output terminal and the second sensor output terminal to the controller includes: providing multiple voltage potential differences to the controller and converting each of the multiple voltage potential differences into multiple temperatures, each provided voltage potential difference corresponding to a different temperature sensor within the stacked battery cell.

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