Battery arrangement with supercooled phase change material

Abstract

The present disclosure provides a battery arrangement with a supercooled phase change material. The supercooling function PCM may be used to release heat to raise the temperature of the battery by triggering a curing phase change in the supercooling function PCM prior to fast charging. The battery temperature management system may include a PCM having a supercooling function in the temperature regulating cell to supply heat to the battery prior to fast charging and absorb heat during fast charging. A vehicle may include a battery and a PCM having a supercooling function in a temperature regulating cell to supply heat to the battery prior to fast charging and absorb heat during fast charging.

Description

Technical Field

[0001] The present disclosure relates to a battery management system. Background Art

[0002] In the context of some batteries, lower operating temperatures may affect lithium plating rates and charge acceptance. To this end, warming the battery before fast charging can improve charge acceptance. Summary of the invention

[0003] A method includes: in response to a request to charge a battery, triggering a first phase change in a supercooled phase change material ("PCM") of a composition adjacent to the battery, the first phase change causing the PCM to solidify to release stored latent heat to warm the battery; and during charging, the PCM absorbs heat while undergoing a second phase change causing the PCM to liquefy to cool the battery.

[0004] A battery temperature management device includes: a temperature regulating cell, the temperature regulating cell including a composition including a phase change material ("PCM") adjacent to a battery, the phase change material being configured to be supercooled; an ultrasonic transducer; and a controller programmed to activate the ultrasonic transducer upon receiving a request to charge the battery, the activation of the ultrasonic transducer causing a first phase change of the PCM, thereby solidifying the PCM to release stored latent heat.

[0005] A vehicle includes: a battery; a temperature regulating cell including a composition including a phase change material ("PCM") adjacent to the battery, the PCM being configured to be supercooled; an immersion pan; and a controller programmed to send an electrical signal to perturb the pan upon receiving a request to charge the battery to trigger a first phase change in the PCM, thereby causing the PCM to solidify to release stored latent heat. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] Figure 1 A method of using a PCM with a supercooling function to warm up a battery cell and cool the battery cell at another time is shown.

[0007] Figure 2 A battery temperature management device is shown.

[0008] Figure 3 Shows Figure 2 Example operation of a battery temperature management device.

[0009] Figure 4 A vehicle is shown.

[0010] Figure 5 Shows Figure 4 Example operation of a vehicle. DETAILED DESCRIPTION

[0011] Embodiments are described herein. However, it should be understood that the disclosed embodiments are merely examples and that other embodiments may take various and alternative forms. The drawings are not necessarily drawn to scale. Some features may be enlarged or minimized to show details of particular components. Therefore, the specific structural details and functional details disclosed herein should not be interpreted as limiting, but merely as a representative basis for teaching those skilled in the art.

[0012] The various features shown and described with reference to any one of the accompanying drawings may be combined with features shown in one or more other drawings to produce embodiments not explicitly shown or described. The combinations of features shown provide representative embodiments for typical applications. However, for specific applications or implementations, various combinations and modifications of features consistent with the teachings of the present disclosure may be desired.

[0013] Fast charging can cause the battery to degrade faster than other charging modes. This degradation is more likely to occur at "cold temperatures" below 30°C. Cold temperatures can cause ion transfer rates to decrease, which can limit the ability of ions to reach the bottom of the electrode. This reduced ion transfer rate can result in slower charging. Charging at low temperatures can also cause lithium plating on the anode surface. Some lithium plating is irreversible, so the process can reduce the battery's lithium inventory, thereby shortening the battery's cycle life.

[0014] When fast charging, a "target temperature" (such as a temperature between about 30°C and about 50°C) can accelerate ion transfer and mitigate lithium plating. By improving ionic conductivity and diffusion in the electrode, the target temperature can reduce polarization of the anode material surface and can lead to faster charging and longer cycle life of the battery.

[0015] "High temperature" (such as a temperature above 60°C) may cause side reactions to shorten the battery life. Therefore, high temperature should be avoided.

[0016] Known battery temperature management systems may include the use of a phase change material ("PCM") or a mixture of PCMs to passively absorb heat above a certain temperature. Example PCMs may include organic materials, inorganic materials, and salt eutectics. For example, when paraffin wax liquefies, it absorbs heat to assume a more energetic phase. Because heat dissipation is a goal of these established methods, many methods teach away from PCMs with a supercooling function (supercooled PCMs) that would retain heat until seed crystals are formed to promote crystallization.

[0017] A PCM with supercooling functionality may be included in a battery temperature management system to improve charge acceptance and extend cycle life by warming up the battery cells prior to rapid charging. Including a PCM with supercooling functionality in a battery temperature management system allows the battery to be cooled and also allows energy to be stored and released at a predetermined time and in a predetermined manner to warm up the battery for rapid charging.

[0018] The PCM having the supercooling function may be included in the composition contained in the temperature regulating cell. The volume of the composition may be smaller than the total volume of the temperature regulating cell, so that the composition may expand when changing phases to fill the space defined by the temperature regulating cell.

[0019] Some existing battery temperature management systems are designed to warm the battery for fast charging by passing an electric current through a resistively heatable material inside or outside the battery. Passing the electric current requires a power source: the battery itself or an additional power source external to the battery. Existing battery temperature management systems may affect the performance of the battery, such as if the battery itself provides power to the resistively heatable material, or may include additional components that may take up space or add weight.

[0020] In a system including a PCM with supercooling capability, the energy used to preheat the battery for rapid charging is the energy stored in the PCM since the last time the PCM was heated above its melting point (which may include the last time the battery was rapidly charged). In addition, a battery temperature management system including a PCM with supercooling capability may use external power to initiate a trigger.

[0021] A PCM may have a different melting point or a different latent heat than another PCM. By including a mixture of two or more PCMs determined through testing, simulation, etc., the composition may have a melting point, for example, between 35°C and 60°C, and a latent heat required for applying a battery temperature management system. For example, a composition with a greater latent heat may heat a battery cell to a higher temperature than a composition with a smaller latent heat in an equivalent system and environment.

[0022] The thermal conductivity of a composition including a PCM having a supercooling function may be less than the thermal conductivity required to warm adjacent battery cells to a target temperature. For example, a composition including a PCM and an additive having a thermal conductivity greater than the PCM may transfer heat to warm adjacent battery cells to a higher temperature than a composition having only the PCM in an equivalent system and environment. Example additives may include graphite or metal foam.

[0023] The relationship between the mass of the composition including the PCM having supercooling function and the mass of the battery cell may affect whether the composition will raise the temperature of the battery cell to the target temperature. The total heat measured in J contained in the mass of the composition may be determined by multiplying the latent heat measured in J / kg of the composition by the mass measured in kg of the composition. Similarly, the final temperature change measured in °C of the battery cell may be determined by dividing the heat measured in J delivered from the composition to the battery cell by the specific heat measured in J / (kg*°C) of the battery and the mass measured in kg of the battery.

[0024] Figure 1 A method of using a PCM with a supercooling function to warm up a battery cell and cool the battery cell at another time is shown. The legend 134 shows arrows plus gradient colors to represent heat transfer. The figure shows a charging request 102, which is transmitted 104 to trigger a phase change 106 in a PCM with a supercooling function. This trigger 106 applied 108 to the supercooled liquid PCM 110 causes a solidification phase change 114. When the liquid PCM 110 undergoes a solidification phase change 114 to become a solid 112, heat is released 116 and the adjacent battery cell 118 is warmed. When the battery is charged 120, heat is generated 122 and a liquefaction phase change 128 is caused in the solid PCM 124. When the solid PCM 124 undergoes a liquefaction phase change 128 to become a liquid 126, the phase change 128 draws heat away from the battery 122, thereby causing 130 cooling of the battery cell 132.

[0025] Figure 2 A battery temperature management device is shown. The battery temperature management device includes a battery cell 212 adjacent to a temperature regulating cell 210. The temperature regulating cell 210 includes a composition including a PCM having a supercooling function 208. An ultrasonic transducer 206 is included in the composition 208, and the ultrasonic transducer 206 is connected 204 to a controller 202. Figure 2 2, the ultrasonic transducer 206 is shown immersed in the composition 208, and the ultrasonic transducer 206 is shown directly connected 204 to the controller 202. Some embodiments may include an ultrasonic transducer 206 that is not immersed as depicted, but is adjacent to the composition 208 or external to the temperature regulating cell 210. Some embodiments may replace the ultrasonic transducer 206 with a different trigger that applies a supercooling function to the PCM, such as an immersed disk that is disturbed by an electrical signal. Some embodiments may connect the controller 202 and the ultrasonic transducer 206 indirectly or wirelessly through an intermediate component.

[0026] Figure 3 Shows Figure 21. Example operation of a battery temperature management device. A controller receives a charge request 302. The controller activates 304 an ultrasonic transducer, and the ultrasonic transducer triggers 306 a composition including a PCM having a supercooling function to undergo a solidification phase change. The phase change generates heat 308, which is conducted to adjacent battery cells.

[0027] Figure 4 Vehicle 402 is shown. Vehicle 402 includes controller 404, and vehicle 402 includes battery cell 414 adjacent to temperature regulating cell 412. Temperature regulating cell 412 includes a composition including a PCM having a supercooling function 410. Immersion pan 408 is included in composition 410, and is connected 406 to controller 404. Figure 4 4, immersion pan 408 is shown as being directly connected 406 to controller 404. Some embodiments may connect controller 402 and immersion pan 408 indirectly or wirelessly through an intermediate component. Some embodiments may replace immersion pan 408 with a different trigger that applies a supercooling function to the PCM, such as an ultrasonic transducer. Some embodiments may connect controller 404 and immersion pan 408 indirectly or wirelessly through an intermediate component. Some embodiments may include immersion pan 408 that includes a metallic substance.

[0028] Figure 5 Shows Figure 4 Example operation of a vehicle. A charge request 502 is transmitted to a controller. The controller perturbs 504 the immersion pan, and the perturbation triggers 506 a composition including a PCM having a supercooling function to undergo a solidification phase change. The phase change generates heat 508, which is conducted to adjacent battery cells. A predetermined mass of the composition causes the battery cells to be heated to between 30°C and 50°C. The amount of mass to achieve this temperature increase can be determined via testing, simulation, etc. Figure 5 , charging request 502 is depicted as originating from outside the vehicle. Some embodiments may include charging request 502 originating from inside the vehicle.

[0029] The algorithm, method or process disclosed herein may be delivered to or implemented by a computer, controller or processing device, which may include any dedicated electronic control unit or programmable electronic control unit. Similarly, the algorithm, method or process may be stored in various forms as data and instructions that can be executed by a computer or controller, including but not limited to information permanently stored on a non-writable storage medium such as a read-only memory device and information that can be changed and stored on a writable storage medium such as an optical disk, a random access memory device or other magnetic and optical media. The algorithm, method or process may also be implemented by a software executable object. Alternatively, a combination of suitable hardware components (such as an application specific integrated circuit, a field programmable gate array, a state machine or other hardware components or devices) or firmware, hardware and software components may be used to implement the algorithm, method or process in whole or in part.

[0030] Although exemplary embodiments are described above, these embodiments are not intended to describe all possible forms encompassed by the claims. Of course, other topologies and variations are conceivable.

[0031] The words used in the specification are words of description rather than limitation, and it is understood that various changes may be made without departing from the spirit and scope of these disclosed materials. For example, the terms "controller" and "controllers" may be used interchangeably herein because the functionality of a controller may be distributed across several controllers / modules that may all communicate via standard techniques.

[0032] As previously mentioned, the features of the various embodiments may be combined to form additional embodiments of the invention that may not be explicitly described or shown. Although various embodiments may have been described as providing advantages or being preferred over other embodiments or prior art implementations with respect to one or more desired characteristics, it will be appreciated by those of ordinary skill in the art that one or more features or characteristics may be compromised to achieve desired overall system properties, depending on the specific application and implementation. These properties may include, but are not limited to, strength, durability, marketability, appearance, packaging, size, serviceability, weight, manufacturability, ease of assembly, and the like. For this reason, embodiments described as being less desirable than other embodiments or prior art implementations with respect to one or more characteristics are not outside the scope of this disclosure and may be desirable for specific applications.

[0033] According to the present invention, a method includes: in response to a request to charge a battery, triggering a first phase change in a supercooled phase change material ("PCM") of a composition adjacent to the battery, the first phase change causing the PCM to solidify to release stored latent heat to warm the battery; and during charging, the PCM absorbs heat while undergoing a second phase change causing the PCM to liquefy to cool the battery.

[0034] In one aspect of the invention, the triggering comprises activating an ultrasonic transducer to cure the composition.

[0035] In one aspect of the invention, the triggering comprises perturbing the immersion pan with an electrical signal to cause the composition to cure.

[0036] In one aspect of the invention, the composition includes a thermally conductive additive such that the thermal conductivity of the composition including the additive is greater than the thermal conductivity of the PCM.

[0037] In one aspect of the invention, a predefined mass of said composition is used to raise the temperature of said cell to between 30°C and 50°C.

[0038] In one aspect of the invention, the composition comprises a predefined mixture of PCMs such that the melting point of the composition is between 35°C and 60°C.

[0039] According to the present invention, a battery temperature management device is provided, having: a temperature regulating cell, the temperature regulating cell comprising a composition including a phase change material ("PCM") adjacent to a battery, the phase change material being configured to be supercooled; an ultrasonic transducer; and a controller programmed to activate the ultrasonic transducer upon receiving a request to charge the battery, thereby causing a first phase change in the PCM, which causes the PCM to solidify and release stored latent heat.

[0040] According to an embodiment, the temperature regulating cell comprises a volume of the composition, the volume of the composition being less than the total volume of the temperature regulating cell, such that the composition can expand when changing phase to fill the space defined by the temperature regulating cell.

[0041] According to an embodiment, the temperature regulating cell comprises a predetermined mass of the composition to raise the temperature of the battery to between 30°C and 50°C.

[0042] According to an embodiment, the composition comprises a mixture of PCMs such that the melting point of the composition is between 35°C and 60°C.

[0043] According to an embodiment, the composition further comprises a thermally conductive additive, such that the thermal conductivity of the composition including the additive is greater than the thermal conductivity of the PCM.

[0044] According to an embodiment, the thermally conductive additive comprises a metal foam.

[0045] According to an embodiment, the thermally conductive additive comprises graphite.

[0046] According to the present invention, a vehicle is provided having: a battery; a temperature regulating cell comprising a composition including a phase change material ("PCM") adjacent to the battery, the PCM being configured to be supercooled; an immersion pan; and a controller programmed to send an electrical signal to perturb the pan upon receiving a request to charge the battery to trigger a first phase change in the PCM, thereby causing the PCM to solidify to release stored latent heat.

[0047] According to an embodiment, the temperature regulating cell comprises a volume of the composition, the volume of the composition being less than the total volume of the temperature regulating cell, such that the composition can expand when changing phase to fill the space defined by the temperature regulating cell.

[0048] According to an embodiment, the temperature regulating cell comprises a predetermined mass of the composition to raise the temperature of the battery to between 30°C and 50°C.

[0049] According to an embodiment, the composition comprises a mixture of PCMs such that the melting point of the composition is between 35°C and 60°C.

[0050] According to an embodiment, the composition further comprises a thermally conductive additive, such that the thermal conductivity of the composition including the additive is greater than the thermal conductivity of the PCM.

[0051] According to an embodiment, the thermally conductive additive is a metal foam.

[0052] According to an embodiment, the thermally conductive additive is graphite.

Claims

1. A method comprising: In response to a request to charge a battery, triggering a first phase change in a supercooled phase change material ("PCM") of a composition adjacent to the battery, the first phase change causing the PCM to solidify to release stored latent heat to warm the battery; and During charging, the PCM absorbs heat while undergoing a second phase change that liquefies the PCM to cool the battery.

2. The method of claim 1, wherein the triggering comprises activating an ultrasonic transducer to cure the composition.

3. The method of claim 1, wherein the triggering comprises perturbing an immersion pan with an electrical signal to cause the composition to cure.

4. The method of claim 1, wherein the composition includes a thermally conductive additive such that a thermal conductivity of the composition including the additive is greater than a thermal conductivity of the PCM.

5. The method of claim 1, wherein a predefined mass of the composition is used to raise the temperature of the battery to between 30°C and 50°C.

6. The method of claim 1, wherein the composition comprises a predefined mixture of PCMs such that the melting point of the composition is between 35°C and 60°C.

7. A battery temperature management device, comprising: a temperature regulating cell comprising a composition including a phase change material ("PCM") adjacent to a battery cell, the PCM being configured to be supercooled; Ultrasonic transducer; as well as A controller is programmed to activate the ultrasonic transducer upon receiving a request to charge the battery, thereby causing a first phase change in the PCM, the first phase change causing the PCM to solidify and release the stored latent heat.

8. A battery temperature management device as described in claim 7, wherein the temperature regulating cell contains a certain volume of the composition, and the volume of the composition is less than the total volume of the temperature regulating cell, so that the composition can expand when changing phase to fill the space defined by the temperature regulating cell.

9. The battery temperature management device of claim 7, wherein the temperature regulating cell comprises a predetermined mass of the composition to raise the temperature of the battery to between 30°C and 50°C.

10. The battery temperature management device of claim 7, wherein the composition comprises a mixture of PCMs such that the melting point of the composition is between 35°C and 60°C. 11 . The battery temperature management device of claim 7 , wherein the composition further comprises a thermal conductivity additive such that a thermal conductivity of the composition including the additive is greater than a thermal conductivity of the PCM.

12. The battery temperature management device of claim 11, wherein the thermally conductive additive comprises a metal foam.

13. The battery temperature management device of claim 11, wherein the thermally conductive additive comprises graphite.

14. A vehicle comprising: Battery; a temperature regulating cell comprising a composition including a phase change material ("PCM") adjacent to the battery, the PCM being configured to be supercooled; Immersion pan; as well as A controller is programmed to send an electrical signal to perturb the disk upon receiving a request to charge the battery to trigger a first phase change in the PCM, thereby causing the PCM to solidify to release the stored latent heat.

15. The vehicle of claim 14, wherein the temperature regulating cell contains a volume of the composition, the volume of the composition being less than the total volume of the temperature regulating cell such that the composition can expand when changing phases to fill a space defined by the temperature regulating cell.

Images