Active pressure control mechanism for improving battery performance

Abstract

A vehicle includes a pressure control device for controlling a pressure at a battery of the vehicle and a method of controlling the pressure of the battery. The supporting plate is arranged on the first side of the battery. The pressing plate is arranged on the second side, opposite to the first side, of the battery. The pressing plate can move relative to the supporting plate so as to control the pressure intensity of the battery. A cam disposed at the platen is configured to rotate to move the platen relative to the support plate. The camshaft rotates the cam to move the platen. The motor generates rotation at the camshaft.

Description

Technical Field

[0001] The present disclosure relates to improving the performance of batteries, and in particular, to controlling the pressure applied to batteries operating under high pressure conditions to improve their performance. Background Art

[0002] Batteries are used to provide power to electric vehicles. When a battery is operated under low pressure conditions, dendrites may grow between the anode and cathode of the battery. These dendrites limit the life and effectiveness of the battery. This is particularly true for lithium metal batteries (LMBs). However, dendrite growth can be reduced by operating the battery under high pressure conditions. Therefore, it is desirable to provide a method and apparatus for applying high pressure to a battery during battery operation. Summary of the invention

[0003] In one exemplary embodiment, a pressure control device for controlling the pressure at a battery of a vehicle is disclosed. The pressure control device includes a support plate at a first side of the battery, a pressure plate disposed at a second side of the battery opposite to the first side, the pressure plate is movable relative to the support plate to control the pressure of the battery, the cam is disposed at the pressure plate and is configured to rotate to move the pressure plate relative to the support plate, the camshaft is configured to rotate the cam to move the pressure plate, and the motor is configured to generate rotation at the camshaft.

[0004] In addition to one or more features described herein, wherein the camshaft is held in a fixed position relative to the support plate. The motor generates rotation at the camshaft via one of: a rotor shaft rotated by the motor and a flexible belt connecting the rotor shaft to the camshaft to convert the rotation of the rotor shaft into the rotation of the camshaft; and a camshaft, which serves as the rotor shaft of the motor. In one embodiment, the cam includes a first cam and a second cam, wherein the first cam and the second cam can be selectively rotated to apply a differential pressure on the pressure plate. The first cam is set to a first angle relative to the camshaft, and the second cam is set to a second angle different from the first angle relative to the camshaft. The camshaft includes a first section and a second section, the first section includes a first cam, and the second section includes a second cam, wherein the first section and the second section can rotate independently of each other. The cam includes a cam groove, and the camshaft includes a pin track, the pin track has a gear pin, and the gear pin is configured to move into the cam groove to engage the camshaft to the cam. The pressure control device also includes a solenoid located at the camshaft for controlling the axial position of the gear pin relative to the cam groove.

[0005] In another exemplary embodiment, a method of controlling operation of a battery of an electric vehicle is disclosed. The method includes rotating a cam against a pressure plate to move the pressure plate relative to a support plate, wherein the battery is disposed between the support plate and the pressure plate, and moving the pressure plate relative to the support plate adjusts pressure within the battery.

[0006] In addition to one or more of the features described herein, the method also includes rotating the cam by rotating a camshaft at a fixed position relative to the support plate. The method also includes rotating the camshaft via a motor, wherein one of: a rotor shaft rotated by the motor is coupled to the rotor shaft via a flexible band; and the camshaft is directly rotated by the motor. The cam includes a cam groove, and the camshaft includes a pin track having a gear pin therein, and also includes moving the gear pin into the cam groove to engage the camshaft to the cam. The cam includes a first cam and a second cam, and also includes applying a differential pressure on the pressure plate using the first cam and the second cam.

[0007] In yet another exemplary embodiment, a vehicle is disclosed. The vehicle includes a battery having a first side and a second side opposite to the first side, and a pressure control device. The pressure control device includes a support plate, a pressure plate, a cam, a camshaft, and a motor, wherein the support plate is at the first side of the battery, the pressure plate is at the second side of the battery, the pressure plate is movable relative to the support plate to control the pressure of the battery, the cam is disposed at the pressure plate and is configured to rotate to move the pressure plate relative to the support plate, the camshaft is configured to rotate the cam to move the pressure plate, and the motor is configured to generate rotation at the camshaft.

[0008] In addition to one or more features described herein, the camshaft is held in a fixed position relative to the support plate. The motor generates rotation at the camshaft via one of: a rotor shaft rotated by the motor and a flexible belt connecting the rotor shaft to the camshaft to convert the rotation of the rotor shaft into the rotation of the camshaft; and a camshaft, which serves as the rotor shaft of the motor. The cam includes a first cam and a second cam, wherein the first cam and the second cam can be selectively rotated to apply a differential pressure on the pressure plate. The first cam is set to a first angle relative to the camshaft, and the second cam is set to a second angle different from the first angle relative to the camshaft. The cam includes a cam groove, and the camshaft includes a pin track having a gear pin therein, the gear pin being configured to move into the cam groove to engage the camshaft to the cam. The vehicle also includes a solenoid located at the camshaft for controlling the axial position of the gear pin relative to the cam groove.

[0009] 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

[0010] Other features, advantages and details appear, by way of example only, in the following detailed description, which refers to the accompanying drawings, in which:

[0011] Figure 1 An electric vehicle according to an exemplary embodiment is shown;

[0012] Figure 2 A battery system for a battery of a vehicle in an exemplary embodiment is shown;

[0013] Figure 3 shows side views of the cam in different rotational configurations;

[0014] Figure 4 shows a perspective view of a battery system in another embodiment;

[0015] Figure 5 shows a perspective view of a battery system in another embodiment;

[0016] Figure 6 shows a perspective view of a battery system in another embodiment;

[0017] Figure 7 shows a perspective view of a section of a camshaft including a cam;

[0018] Figure 8 A side view of a camshaft is shown, showing means for engaging the cam to the camshaft;

[0019] Fig. 9 A perspective view showing a battery system in another embodiment; and

[0020] Fig.10 A side view of a battery system is shown. DETAILED DESCRIPTION

[0021] The following description is merely exemplary in nature and is not intended to limit the present disclosure, its application, or uses. It should be understood that throughout the drawings, corresponding reference numerals indicate the same or corresponding parts and features.

[0022] According to an exemplary embodiment, Figure 1 An electric vehicle 100 is shown. The electric vehicle 100 includes an electric motor 102, a battery system 104, and a controller 106. The battery system 104 includes a battery 108, which includes an anode 110 and a cathode 112, which are susceptible to forming dendrites during operation at standard pressure or ambient pressure. Dendrites reduce the operating quality of the battery 108. In various embodiments, the battery 108 is any battery that requires high pressure conditions to operate, such as a lithium metal battery (LMB). The battery system 104 includes a device that applies pressure to the battery 108 and is capable of adjusting or controlling the pressure as needed.

[0023] The controller 106 may include processing circuitry that may include an application specific integrated circuit (ASIC), electronic circuitry, a processor (shared, dedicated, or group) and memory that executes one or more software or firmware programs, combinatorial logic circuitry, and / or other suitable components that provide the described functionality. The controller 106 may include a non-transitory computer-readable medium storing instructions that, when processed by one or more processors of the controller 106, implement a method of operating the battery system 104 to apply pressure at the battery 108 as desired.

[0024] Figure 2 A battery system 200 for a battery 108 in an exemplary embodiment is shown. The battery system 200 includes a housing 202 that accommodates the battery 108. The housing 202 may have a bottom surface 204, a top surface 206, and a sidewall 208. A pressure control device 210 for the battery 108 is disposed inside the housing 202. The pressure control device 210 includes a support plate 212 on which the battery 108 is disposed, a pressure plate 214 that is movable relative to the support plate, and a column 216 that guides the movement of the pressure plate in a direction toward or away from the support plate. The support plate 212 may be the same as the bottom surface of the housing 202. The support plate 212 is placed against a first side of the battery 108, and the pressure plate 214 is placed against a second side of the battery 108 that is opposite to the first side. The pressure plate 214 may move toward the support plate 212 to increase the pressure applied to the battery 108. The pressure plate 214 may move away from the support plate 212 to reduce the pressure applied to the battery 108.

[0025] The platen control 218 controls the movement of the platen 214, thereby controlling the pressure within the battery 108. The platen control 218 includes a camshaft 220 and one or more cams disposed on the camshaft. For illustrative purposes, a first cam 222 and a second cam 224 are shown. A motor 226 is coupled to the camshaft 220 and controls the rotation of the camshaft. In an embodiment, the motor 226 includes a rotor shaft 227 and is coupled to the camshaft 220 via a flexible belt 232, which converts the rotation of the rotor shaft into the rotation of the camshaft. The motor 226 can be coupled to the housing 202.

[0026] The camshaft 220 is coupled to at least one surface of the housing 202. The camshaft 220 may be supported by bearings. For illustration purposes, a first bearing 228 and a second bearing 230 are shown. The bearings allow the camshaft 220 to rotate freely. The bearings may be supported by the top surface 206 of the housing 202. Alternatively, the bearings may be located in one or more opposing side walls of the housing 202. The camshaft 220 is held in a fixed position relative to the support plate 212. Thus, rotating the camshaft 220 (and the first cam 222 and the second cam 224) changes the distance between the pressure plate 214 and the support plate 212, as shown in FIG. Figure 3 shown.

[0027] The pressure sensor 240 is configured to detect the pressure within the battery 108. The pressure may be sent to the controller 106 or other suitable processor. The controller 106 may control the operation of the motor based on the detected pressure within the battery 108.

[0028] Figure 3 A side view 300 of a cam (e.g., a first cam 222) in different rotational configurations is shown. The cam has a base circle 302 and a cam 304 on one side. The base circle 302 has a first radius r1, and the cam 304 has a second radius r2 that is greater than the first radius r1. The cam is positioned so that the surface of the cam contacts the outer surface of the pressure plate 214. The cam rotates around a rotation center O, which is along the cam shaft 220 and remains stationary relative to the support plate 212. A first rotation angle 306 is shown, where the cam contacts the pressure plate 214 at a point along the base circle 302. As a result, the pressure plate 214 is separated from the rotation center O by a first distance d1. A second rotation angle 308 is shown, where the cam contacts the pressure plate at a point along the cam 304. As a result, the pressure plate 214 is separated from the rotation center O by a second distance d2 that is greater than d1. Therefore, the pressure plate 214 is closer to the support plate 212 when the cam is at the second rotation angle 308 than when the cam is at the first rotation angle 306 , and applies a greater pressure to the battery 108 .

[0029] Figure 4 A perspective view 400 of a battery system 200 in another embodiment is shown. The motor 226 has a first rotor shaft 402 extending in one direction parallel to the camshaft 220 and a second rotor shaft 404 extending in an opposite direction parallel to the camshaft. The first rotor shaft 402 may be supported at a first bearing 406 coupled to the top surface 206, and the second rotor shaft 404 may be supported at a second bearing 408 coupled to the top surface 206. The first rotor shaft 402 is coupled to the camshaft 220 at a first location 410 via a first flexible band 412, and the second rotor shaft 404 is coupled to the camshaft 220 at a second location 414 via a second flexible band 416.

[0030] Figure 5 A perspective view 500 of a battery system 200 in another embodiment is shown. The camshaft 220 is coupled to the top surface 206 of the housing 202 via a first bearing 228 at a first end 502 and a second bearing 230 at a second end 504. The first end 502 of the camshaft 220 passes through the center of the motor 226 to serve as the rotor shaft of the motor. Thus, the motor 226 can rotate the camshaft 220 without the use of a flexible band. The motor 226 can be attached to either the top surface 206 or the sidewall 208 of the housing 202.

[0031] Figure 6 A perspective view 600 of the battery system 200 in another embodiment is shown. The first end 502 of the camshaft 220 passes through the center of the motor 226 to serve as the rotor shaft of the motor. The motor 226 is attached to the side wall 208 of the housing 202. The second end 504 of the camshaft 220 is coupled to the opposite side wall 208 of the housing 202.

[0032] Figure 7 A perspective view 700 of a section of a camshaft 220 including a cam is shown. The camshaft 220 includes a longitudinal groove or pin track 702 extending along a section of the camshaft. A gear pin 704 is located within the pin track 702 and can be moved to a selected position within the pin track. The cam includes a hole through which the camshaft passes. The cam is arranged along the camshaft so that the pin track 702 passes through at least a portion of the cam. A plurality of cam grooves 706 extend radially outward from the hole at a plurality of angular positions.

[0033] In operation, the gear pin 704 is disposed within one of the cam grooves (e.g., the first cam groove 708) to secure the cam to the camshaft 220. The camshaft 220 can then be rotated to rotate the cam to apply a selected force to the pressure plate 214 ( Figure 2 ). The relative angular position between the cam and the camshaft can be adjusted by sliding the gear pin 704 away from the cam through the pin track 702 until it leaves the first cam groove 708. The cam is then rotated relative to the camshaft 220, or the camshaft is rotated relative to the cam, until the pin track 702 is aligned with another of the cam grooves (e.g., the second cam groove 710). The gear pin 704 then slides through the pin track 702 to engage the cam at the second cam groove 710.

[0034] Figure 8A side view 800 of the camshaft 220 is shown, which shows a device for engaging a cam to the camshaft 220. The camshaft 220 includes a cam housing 802 and a core 804 that is slidable within the cam housing 802. The core 804 includes a first cavity 806 located on one side of the first cam 222 and a second cavity 808 located on one side of the second cam 224. A first gear pin 810 is disposed in the first cavity 806 having a first spring 812 that biases the first gear pin toward the first cam 222. A second gear pin 816 is disposed in the second cavity 808 having a second spring 814 that biases the second gear pin toward the second cam 224.

[0035] The solenoid 818 is disposed at the end of the camshaft 220. The core 804 includes a magnetic material 819 located within the solenoid 818. When the solenoid 818 is turned off, the core 804 is in a first axial position within the cam housing 802, in which the first cavity 806 and the second cavity 808 are away from the first cam 222 and the second cam 224, respectively.

[0036] When the solenoid 818 is turned on (first configuration 820), the core 804 is forced into a second axial position within the cam housing, in which the first cavity 806 moves toward the first cam 222 and the second cavity 808 moves toward the second cam 224. As shown, the first cam 222 rotates at an angle where the first gear pin 810 is not aligned with any cam groove of the first cam. Therefore, the first spring 812 is compressed, but the first gear pin 810 does not engage with the first cam 222. However, the camshaft can be rotated to align the first gear pin 810 with the selected cam groove, at which time the first spring 812 biases the first gear pin into the selected cam groove to engage the first cam 222. In addition, the second cam 224 rotates at an angle where the second gear pin 816 is aligned with the cam groove of the second cam 224. Therefore, the second spring 814 is able to bias the second gear pin 816 to engage with the second cam 224.

[0037] Reference again Figure 2 , since the angular position of the cam relative to the camshaft 220 can be selected, the first cam 222 and the second cam 224 can have different angular positions. For example, the first cam 222 can be set at a first angle θ, and the second cam 224 can be set at a second angle (e.g., θ+5°). In this configuration, the second cam 224 can apply a greater force to the pressure plate than the first cam 222 at the same rotation of the camshaft 220. Therefore, different forces and pressures can be applied at different locations on the movable plate and in the battery.

[0038] Fig. 9A perspective view 900 of a battery system 200 in another embodiment is shown. The camshaft 220 includes a first section 902 including a first cam 222 and a second section 904 including a second cam 224. The first section 902 and the second section 904 can rotate independently of each other. A first motor 906 is coupled to the first section 902, and a second motor 908 is coupled to the second section 904. The first motor 906 and the second motor 908 can be independently operated to provide different rotations of their first cam 222 and second cam 224, respectively. Therefore, different pressures can be applied at different locations within the battery 108. It should be understood that in various embodiments, the camshaft 220 can have more than two independently rotating sections, each of which includes its own cam.

[0039] Fig.10 A side view 1000 of the battery system 200 is shown. The side view shows a first camshaft 1002 and a second camshaft 1004 at different locations along the pressure plate 214. The camshafts can be placed to provide the desired pressure at different locations along the pressure plate. Each camshaft can rotate independently. It should be understood that in various embodiments, there can be more than two camshafts.

[0040] The terms "one" and "an" do not indicate a limitation of quantity, but rather indicate the presence of at least one of the referenced item. 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.

[0041] 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.

[0042] 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, as of the filing date of the earliest priority application in which the test standards appear.

[0043] 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.

[0044] 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 elements thereof may be substituted with equivalents without departing from the scope thereof. 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 pressure control device for controlling the pressure at a battery of a vehicle, comprising: a support plate at a first side of the battery; a pressure plate, the pressure plate being disposed at a second side of the battery opposite to the first side, the pressure plate being movable relative to the support plate to control the pressure of the battery; a cam disposed at the pressure plate and configured to rotate to move the pressure plate relative to the support plate; a camshaft configured to rotate the cam to move the pressure plate; as well as A motor is configured to generate rotation at the camshaft.

2. The pressure control device according to claim 1, wherein: The camshaft is held in a fixed position relative to the support plate.

3. The pressure control device according to claim 1, wherein: The motor generates rotation at the camshaft via one of: (i) a rotor shaft rotated by the motor and a flexible belt connecting the rotor shaft to the camshaft to convert rotation of the rotor shaft into rotation of the camshaft; and (ii) the camshaft, which serves as a rotor shaft of the motor.

4. The pressure control device according to claim 1, wherein: The cam includes a first cam and a second cam, wherein the first cam and the second cam are selectively rotatable to apply differential pressures on the pressure plate.

5. The pressure control device according to claim 1, wherein: The cam includes a cam groove and the camshaft includes a pin track having a gear pin therein, the gear pin being configured to move into the cam groove to engage the camshaft to the cam.

6. A method of controlling the operation of a battery of an electric vehicle, comprising: A cam is rotated against a pressure plate to move the pressure plate relative to a support plate, wherein the battery is disposed between the support plate and the pressure plate, and moving the pressure plate relative to the support plate adjusts the pressure within the battery.

7. The method of claim 6, further comprising rotating the cam by rotating a cam shaft at a fixed position relative to the support plate.

8. The method of claim 7, further comprising rotating the camshaft via a motor, wherein one of: (i) a rotor shaft rotated by the motor is coupled to the rotor shaft via a flexible band; and (ii) the camshaft is directly rotated by the motor.

9. The method according to claim 7, wherein: The cam includes a cam groove and the camshaft includes a pin track having a gear pin therein, the method further comprising moving the gear pin into the cam groove to engage the camshaft to the cam.

10. The method according to claim 6, wherein: The cam includes a first cam and a second cam, and the method further includes applying a differential pressure on the pressure plate using the first cam and the second cam.

Images