Pressure control of battery cells

Abstract

A pressure management system includes a pressure plate disposed in an initial position relative to a battery cell disposed in a housing where expansion of the battery cell causes an expansion force to be applied to the pressure plate. The pressure management system also includes a mechanical linkage coupled to the pressure plate, the mechanical linkage configured to move in a lateral direction in response to the expansive force and to convert the expansive force into a reaction force opposite the expansive force, and a biasing system including a biasing member configured to resist lateral movement of the mechanical linkage. The biasing system is configured to apply a biasing force in an opposite direction to the lateral direction that causes the mechanical linkage to apply a selected proportion of a reaction force as an expansive force.

Description

Technical Field

[0001] The present invention relates to a battery system, and in particular to pressure management of a battery cell of a battery system. Background Art

[0002] Battery pouch cells are used in a variety of applications, such as automotive applications (e.g., electric and hybrid vehicles). For example, electric and hybrid vehicles include a battery system that includes a battery pack that houses a plurality of battery cells, which may include pouch-type battery cells, such as lithium-ion battery cells. As such batteries are charged and discharged, and as such batteries age, pressure changes occur, which can be detrimental to charging and power storage capabilities. It is desirable to provide a mechanism for maintaining a battery pack cell at a substantially constant pressure during its operating life. Summary of the invention

[0003] In an exemplary embodiment, a pressure management system includes a pressure plate disposed in an initial position relative to a battery cell disposed in a housing, wherein expansion of the battery cell causes an expansion force to be applied to the pressure plate. The pressure management system also includes a mechanical linkage connected to the pressure plate, the mechanical linkage configured to move in a lateral direction in response to the expansion force and convert the expansion force into a reaction force opposite to the expansion force, and a biasing system including a biasing member configured to resist lateral movement of the mechanical linkage. The biasing system is configured to apply a biasing force in a direction opposite to the lateral direction, the biasing force causing the mechanical linkage to apply a reaction force that is a selected proportion of the expansion force.

[0004] In addition to one or more features described herein, the biasing member has a spring constant selected such that the biasing force causes the reaction force to be a selected proportion of the expansion force.

[0005] In addition to one or more features described herein, the system also includes a stop member configured to limit lateral movement of the mechanical linkage, directing a portion of the lateral force generated by the mechanical linkage toward the battery cell based on a reaction force generated by the stop member.

[0006] In addition to one or more features described herein, the biasing member is a spring having a first end and a second end, the first end of the spring being configured to couple with the mechanical linkage and the second end of the spring being coupled to the stop component.

[0007] In addition to one or more features described herein, the mechanical linkage device also includes a pivot member having a first end and a second end, the first end being connected to the pressure plate at a first pivot point, the pivot member being configured to rotate about a fixed pivot point, the fixed pivot point being located between the first end and the second end, and the fixed pivot point having a fixed position relative to the housing.

[0008] In addition to one or more features described herein, the mechanical linkage includes a connecting member having a third end and a fourth end, the third end connected to the second end via a second pivot point, and the fourth end is movable in a lateral direction.

[0009] In addition to one or more features described herein, the system also includes a bias control device operable to adjust the biasing force of the biasing member.

[0010] In addition to one or more features described herein, the bias control device includes a pinion connected to the linear gear, the pinion connected to an actuator, and the actuator is configured to rotate the pinion to adjust the bias force.

[0011] In another exemplary embodiment, a method of controlling pressure of a battery cell includes receiving an expansion force on a pressure plate disposed at an initial position relative to the battery cell, the battery cell being disposed in a housing, the expansion force being generated by expansion of the battery cell, and managing the pressure of the battery cell by a pressure management system, the pressure management system including a mechanical linkage connected to the pressure plate and a biasing system including a biasing member. Managing the pressure includes converting the expansion force into a reaction force based on lateral movement of the mechanical linkage in a lateral direction, the reaction force being configured to oppose the expansion force, and controlling the reaction force based on the biasing system resisting the lateral movement of the mechanical linkage. The biasing system applies a biasing force in a direction opposite to the lateral direction via the biasing member, the biasing force causing the mechanical linkage to apply a reaction force that is a selected proportion of the expansion force.

[0012] In addition to one or more features described herein, the pressure management system includes a stop member configured to limit lateral movement of the mechanical linkage, directing a portion of the lateral force generated by the mechanical linkage toward the battery cell based on a reaction force generated by the stop member.

[0013] In addition to one or more features described herein, the biasing member is a spring having a first end configured to couple to the mechanical linkage and a second end of the spring coupled to the stop component.

[0014] In addition to one or more features described herein, the mechanical linkage includes a pivot member having a first end and a second end, the first end connected to the pressure plate at a first pivot point, the pivot member configured to rotate about a fixed pivot point, the fixed pivot point located between the first end and the second end, and the fixed pivot point having a fixed position relative to the housing.

[0015] In addition to one or more features described herein, the mechanical linkage includes a connecting member having a third end and a fourth end, the third end connected to the second end via a second pivot point, and the fourth end is movable in a lateral direction.

[0016] In addition to one or more features described herein, the method also includes adjusting the biasing force of the biasing member by operating a biasing control device.

[0017] In addition to one or more features described herein, the bias control device includes a pinion connected to the linear gear, the pinion is connected to the actuator, and controlling the reaction force includes controlling the actuator to rotate the pinion to adjust the bias force.

[0018] In another exemplary embodiment, a vehicle system includes a battery system connected to a vehicle motor, the battery system including a battery cell disposed in a housing, and a pressure management system including a pressure plate disposed in an initial position relative to the battery cell, wherein expansion of the battery cell causes an expansion force to be applied to the pressure plate. The pressure management system also includes a mechanical linkage connected to the pressure plate, the mechanical linkage being configured to move in a lateral direction in response to the expansion force and convert the expansion force into a reaction force opposite to the expansion force, and a biasing system configured to resist lateral movement of the mechanical linkage. The biasing system includes a biasing member configured to apply a biasing force in a direction opposite to the lateral direction, the biasing force causing the mechanical linkage to apply a reaction force that is a selected proportion of the expansion force.

[0019] In addition to one or more features described herein, the spring constant of the biasing member is selected so that the biasing force produces a reaction force in a selected proportion to the expansion force.

[0020] In addition to one or more features described herein, the pressure management system includes a stop member configured to limit lateral movement of the mechanical linkage, directing a portion of the lateral force generated by the mechanical linkage toward the battery cell based on a reaction force generated by the stop member.

[0021] In addition to one or more features described herein, the biasing member is a spring having a first end configured to be coupled to the mechanical linkage and a second end of the spring coupled to the stop component.

[0022] In addition to one or more features described herein, the pressure management system includes a bias control device for adjusting the biasing force of the biasing member.

[0023] The above features and advantages and other features and advantages of the present invention are readily apparent from the following detailed description when taken in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Other features, advantages and details appear by way of example only in the following detailed description, which refers to the accompanying drawings, in which:

[0025] Figure 1An energy storage system according to an exemplary embodiment is shown, including a housing containing one or more battery cells and a pressure management system;

[0026] Figure 2A and 2B depicts an energy storage system including a pressure management system including one or more mechanical linkages and a biasing system according to an exemplary embodiment;

[0027] Figure 3 schematically illustrates a pressure management system according to an exemplary embodiment;

[0028] Figure 4 A conventional pressure management system is schematically illustrated;

[0029] Figure 5 for Figure 3 The parameters of the pressure management system shown are Figure 4 A comparison diagram of parameters of a conventional pressure management system is shown;

[0030] Figures 6A-6C is a diagram according to an exemplary embodiment, depicting Figure 2A and 2B The biasing system cooperates with the various forces generated by the connecting mechanism during operation;

[0031] Fig. 7A and 7B depicts an energy storage system including a pressure management system including one or more mechanical linkages and a biasing system including one or more inclined or slanted biasing members according to an exemplary embodiment;

[0032] Fig. 8A and 8B depicts an energy storage system including a pressure management system including one or more mechanical linkages and an adjustable biasing system according to an exemplary embodiment;

[0033] Fig. 9A and 9B Depicted is a schematic diagram of an exemplary embodiment of the present invention. Fig. 8A and 8B An adjustment device for the bias system;

[0034] Fig.10 is a flow chart describing a method of managing pressure in a battery system according to an exemplary embodiment;

[0035] Fig.11 depicts a motor vehicle including a battery system and a pressure management system according to an exemplary embodiment; and

[0036] Fig.12A computer system according to an exemplary embodiment is depicted. DETAILED DESCRIPTION

[0037] The following description is merely exemplary in nature and is not intended to limit the invention, its application or uses. It should be understood that throughout the drawings, corresponding reference numerals indicate the same or corresponding components and features.

[0038] According to one or more exemplary embodiments, methods, devices, and systems for controlling pressure in battery systems and battery assemblies are provided. One embodiment of a pressure management system includes a pressure plate disposed in a housing of a battery assembly (e.g., a battery pack or a battery module), which can move in response to an expansion force generated by the expansion of one or more battery cells in the housing. The pressure management system also includes one or more mechanical linkages that convert a portion of the expansion force into a reaction force or reverse force to maintain or achieve a desired pressure in the battery cell. In one embodiment, the pressure management system includes a biasing system that cooperates with the mechanical linkage to generate a reverse force.

[0039] In one embodiment, the mechanical linkage includes a first elongated member (referred to as a "pivoting member") and a second elongated member (referred to as a "connecting member"). The pivoting member is attached to the pressure plate at one end, for example, by a pivot, and is attached to one end of the connecting member at the other end by another pivot. The pivoting member is also connected to a fixed pivot, which is connected to the housing. When an expansion force is applied to the pressure plate, movement of the pressure plate causes one end of the connecting member to move laterally toward a stop member (i.e., along the pressure plate and / or in a direction perpendicular to the direction of the expansion force). When the connecting member engages a stop member or other resistance member, the lateral force applied by the connecting member is converted into a reaction force or reverse force proportional to the expansion force.

[0040] In one embodiment, the pressure management system includes a biasing system that can be selected to control the reverse force (e.g., to make the reverse force a desired proportion of the expansion force). For example, the biasing system includes a laterally extending spring connected to a stop member. When the connecting member moves a given distance, the connecting member engages the spring, and the spring applies a spring force that resists the movement of the connecting member. The magnitude of the spring force can be calibrated or adjusted, for example, by selecting a spring with an appropriate spring constant and / or by incorporating a spring adjuster that can be actuated to modify the spring force.

[0041] The embodiments described herein have numerous advantages and technical effects. These embodiments provide improved battery function by maintaining a constant force on the battery cell during the battery cell life, thereby effectively controlling pressure and avoiding negative effects such as dendrite growth. In addition, the embodiments provide effective pressure control that requires less volume than existing systems.

[0042] This embodiment has advantages over existing pressure compensation systems. For example, existing systems may use springs to resist expansion forces; however, such systems require a significant increase in the volume required for the battery module or housing to accommodate springs with sufficient elastic force to maintain the desired pressure. This embodiment can provide effective pressure management in a relatively small volume.

[0043] Figure 1 An embodiment of an energy storage device or system 10 is depicted that includes a battery module 12 housing a group (i.e., one or more) of battery cells 14. Each battery cell 14 can be any type of cell that is rechargeable, such as a lithium-based cell (e.g., lithium-ion, lithium metal (LMB), etc.). For example, each battery cell 14 is a pouch-type lithium-ion battery.

[0044] The module 12 includes a housing 16 in which one or more battery cells 14 are disposed. If multiple batteries are housed, they may be stacked as shown, with adjacent battery cells 12 separated by support plates 18. Note that the embodiments described herein are not limited to the type or size of the housing 16, the type, size, or number of battery cells shown, or the type of battery shown.

[0045] The battery module 12 includes or is connected to a pressure management system 20 that is configured to automatically manage the pressure in the battery cells 14. The pressure management system 20 includes a pressure plate 22 disposed above the battery cells 14. The pressure plate 22 has a default position, which may be a position where the pressure plate 22 contacts the battery cells 14 (e.g., resting on the uppermost battery cell 14). Optionally, as Figure 1 As shown, the default position defines a gap or clearance that allows a certain amount of battery cell expansion before triggering pressure compensation or management. Note that the pressure plate 22 can be set in any position or location (e.g., below the battery cell 14) so ​​that the expansion of the battery cell causes the movement of the pressure plate 22.

[0046] The pressure compensation device is disposed on the pressure plate 22 or otherwise connected to the pressure plate 22 and is configured to apply a reaction force on the pressure plate to compensate for the expansion of the battery cell 14 and maintain the battery cell 14 at a desired pressure (or within a desired pressure range).

[0047] The pressure compensation device includes a set (i.e., one or more) of mechanical linkages 24 that can convert the force on the pressure plate 22 into an opposing force (i.e., in the opposite direction of the expansion force). For example, when the battery cell 14 expands and exerts an upward force on the pressure plate, the mechanical linkage 24 operates to exert a proportional downward force. Each mechanical linkage 24 can be calibrated to provide a downward force that maintains a constant selected pressure on the battery cell as the battery cell expands.

[0048] like Figure 1 As shown, the pressure compensation device includes two mechanical linkages 24 located at opposite ends of a pressure plate 22. The pressure plate 22 is oriented so that a surface 23 facing the battery cell 14 defines a plane orthogonal to the expansion direction. For example, the direction of expansion is along the z-axis (i.e., in the z-direction), and the surface is parallel to the plane defined by the x-axis and the y-axis.

[0049] Each mechanical linkage 24 includes a first member 26 ("pivot member") located at a fixed pivot point P0 relative to the housing 16 (i.e., a pivot point having a fixed position relative to the housing 16), about which the pivot member 26 can rotate. One end of the pivot member 26 is connected to the pressure plate 22 at the pivot point P1 so that the pivot member 26 can rotate about the pivot point P1. The other end of the pivot member 26 is connected to one end of the connecting member 28 at the pivot point P2.

[0050] The other end of the connecting member 28 is connected to the pressure plate 22, so that the force due to expansion (referred to as "expansion force", F e indicates) exceeds a certain threshold force F t When the expansion force F e The pressure plate 22 is pushed upward (in the z-direction). This causes the pivot member 26 to rotate about the pivot point P0. The rotation of the pivot member 26, in turn, causes the end 30 of the connecting member 28 to move laterally (e.g., in the x-direction) or to apply a lateral force toward the center of the pressure plate 22. The "lateral" direction can be a direction orthogonal to the direction of the expansion force (e.g., in the xy plane) or a direction along the surface of the pressure plate 22.

[0051] The pressure plate 22 includes or is connected to a stop member 32, which may be a raised structure, that counteracts lateral movement of the connecting member 28. When the connecting member 28 engages the stop member 32, the reactive lateral force results in a reactive force (also referred to as a "reverse force", denoted by F r ) is applied to the battery cell 14. The reverse force F r and expansion force F e Parameters of the mechanical linkage 24 may be selected to calibrate the mechanical linkage 24 to achieve a desired ratio of opposing forces. Examples of these parameters include the lengths of the pivot member 26 and the connecting member 28, the height of the pivot point P1, the location of the pivot point P2, the location of the stop member 32, etc. As discussed further herein, parameters of the biasing system may also be selected or adjusted to calibrate the pressure management system 20.

[0052] In one embodiment, the pressure management system 20 includes a biasing system that provides one or more pressure elements configured to control the opposing force F r The size of the component (ie, the expansion force F that controls the redirection of the battery cell 14)e The biasing system may be a passive or active system which may be designed to maintain and / or adjust the desired ratio.

[0053] Figure 2A and 2B An embodiment of the pressure management system 20 is shown in which the system is a passive system. In this embodiment, the pressure management system 20 includes laterally extending springs 34 configured to resist lateral movement of each connecting member 28. Each spring 34 applies a biasing force opposing the lateral movement. Figure 2A The pressure plate is shown in its initial or default position, in which the default opposing force F d applied to the battery cell 14 .

[0054] As shown, each spring 34 is connected or attached to the stop member 32 at one end of the spring 34. The other end of each spring 34 is located laterally away from the stop member 32 and is configured to engage with the corresponding connecting member 28.

[0055] The biasing force is a function of the spring constant k of the spring 34. When the battery cell 14 expands and applies an expansion force F to the pressure plate 22 e , the upward movement of the pressure plate 22 causes each pivot member 26 to rotate about its respective fixed pivot point P0, which in turn causes lateral movement of each connecting member 28. This lateral movement exerts a lateral force on the spring 34 (e.g., through the end of the connecting member at or near point P3) and compresses the spring, such as Figure 2B The spring 34 applies an opposing biasing force (also referred to as "spring force") which depends on the spring constant k.

[0056] By choosing an appropriate spring constant k, the opposing force F r The magnitude of the expansion force F e For example, a spring with a higher spring constant (and higher stiffness) corresponds to a higher ratio, while a spring with a lower spring constant corresponds to a lower ratio.

[0057] Please note that embodiments are not limited to the number and location of mechanical linkages described herein. For example, the pressure management system 20 may include one linkage 24 on one side of the pressure plate 22. In addition, there may be more than one linkage 24 arranged along the y-direction.

[0058] Figure 3 and Figure 4 Various aspects of the pressure management system described herein, as well as various aspects of conventional systems, are described. Figure 5 A comparison between features of the embodiments described herein and conventional systems is shown.

[0059] Figure 3 Various aspects of the battery cell 14 are schematically shown, along with the mechanical linkage 24 and the transverse spring 34. By way of comparison, Figure 4 An example of a conventional system is shown in , which includes a vertically oriented spring 40 having a fixed end 42 connected to the housing 16 and a movable end 44 that exerts a vertical spring force on the battery cell 14. The transverse spring 34 and the spring 40 have the same spring constant.

[0060] exist Figure 3 and Figure 4 In FIG. 1 , when the battery is at 100% state of charge (SOC) and fully expanded, a distance d is defined between the surface S2 of the battery cell 14 and the upper surface S1 of the housing 16. As the SOC decreases, the battery cell surface recedes, and the total distance between the battery surface and the upper surface increases by a distance Δd. At 100% SOC, Δd decreases toward zero as the SOC decreases.

[0061] Figure 5 A graph 50 of force F as a function of Δd is shown. In graph 50, Δd is maximum at the origin of the graph and decreases to zero as the battery cell 14 expands. Curve 52 shows the spring force of the vertical spring 40, which increases linearly as a function of Δd. Point 54 represents the balance between the spring force and the expansion force at 0% SOC, and point 56 represents the balance at 100% SOC.

[0062] Figure 5 Also included is a curve 58 representing the spring force of spring 34 of an embodiment of pressure management system 20. Point 60 represents the balance between the spring force and the expansion force at 0% SOC, and point 62 represents the balance at 100% SOC. The shape of curve 58 is affected by the spring constant and the design of the mechanical linkage.

[0063] Thus, due to the laterally extending spring 34 and the mechanical linkage 24, the pressure management system 20 can effectively maintain a constant pressure with a small volume.

[0064] Figures 6A-6C For purposes of illustration, force transmission using a mechanical linkage 24 and a biasing member such as a spring 34 is depicted. Figures 6A-6C Various aspects of calculating forces and selecting spring characteristics to obtain the desired opposing forces are also shown.

[0065] In these figures, l 1 is the length from the pivot point P1 to the pivot point P0 in the xz plane, l 2 is the length from the pivot point P0 to the pivot point P2, l 3is the length from pivot point P2 to pivot point P3. Pivoting member 26 defines an angle θ relative to the x-axis (or the lateral direction of movement of end portion 30). 1 , and the connecting member 28 defines an angle θ relative to the x-axis 3 .

[0066] like Fig. 6A As shown, when the force F 1 When the expansion force is applied perpendicularly (in the z direction or parallel to the expansion direction) to the pressure plate 22, the pivot member 26 rotates about the pivot point P0, generating a force F on the connecting member 28. 2 , thereby causing the connecting member 28 to move along the x direction and generate a lateral force F 3 .

[0067] like Figure 6B As shown, the connecting member 28 pushes the spring 34, which causes the spring 34 to apply an opposing spring force f s . Spring force f s With distance d 3 Proportional, distance d 3 is the lateral distance that point P3 moves due to the expansion force. Spring 34 has a spring constant k, and a spring force f s is k times d 3 (f s =k*d 3 )

[0068] When the mechanical linkage 24 is in a steady state, the mechanical linkage 24 does not move. Figure 6C As shown, the pivot member 26 and the connecting member 28 can be considered as a rigid body with a fulcrum at point P0. In this case, the mechanical linkage 24 applies a force F 4 Force F 4 With normal component F 4 N , which represents the reverse force applied to the battery cell 14.

[0069] In steady state conditions, the total torque is zero and can therefore be expressed as:

[0070] l 1 F 1 +l 4 F 4 =0

[0071] Among them l 4 is the length from point P0 to P3 ( Figure 6C ).therefore,

[0072]

[0073] Normal component F 4N , i.e. the reverse force, can be calculated according to the following formula:

[0074]

[0075] Length 4 As d 3 and spring force f s Therefore, the length l 4 and angle θ 3 is a function of k. Therefore, k can be selected to calibrate the pressure management system 20 and produce a reaction force with a desired ratio to the expansion force.

[0076] In addition to the spring constant k, other aspects of the pressure management system 20 may be selected or designed to control the opposing force. For example, the lengths of the pivot member 26 and the connecting member 28 and the locations of the pivot points P0 and P1 may be varied to affect the opposing force.

[0077] Fig. 7A and 7B Depicted are examples of design features that may be selected, in combination with other features such as spring constant, to achieve a desired opposing force. Fig. 7A The pressure plate 22 is shown in an initial or default position, in which the default opposing force F r applied to the battery cell 14 . Figure 7B The pressure management system 20 is shown when the battery cell 14 has expanded, which causes the connecting member 28 to move laterally and compress the spring 34 .

[0078] In this example, the spring 34 is in an inclined configuration, wherein the spring 34 forms an initial angle θ relative to the surface of the pressure plate 22. s Angle θ s can be designed to influence the resulting spring force f s The size of the reverse force and the expansion force F corresponding to the reverse force e proportion.

[0079] like Fig. 7A and 7B As shown, the angle θ can be determined by connecting one end of the spring 34 to the support structure 70. s The ends may be connected so that the spring 34 can remain linear by rotating about the pivot point P4. Features such as the pivot point P4 and the height of the support structure 70 (eg, in the z-direction) may be selected to define the angle and corresponding spring force.

[0080] In one embodiment, the pressure management system 20 is configured to be adjustable to change the opposing force F r Relative to the expansion force F eThe pressure management system 20 may include a bias control system that can be actively controlled at any time to change the relationship between the expansion force and the opposing force to control the pressure in one or more battery cells.

[0081] Fig. 8A and 8B An embodiment of the pressure management system 20 is depicted, including a biasing member adjustment system 80. The adjustment system includes an adjustment device, referred to as a spring adjuster 82. The spring adjuster 82 is coupled to the spring 34 and is controllable to increase or decrease spring compression, thereby controlling the spring force (i.e., the amount of spring force resulting from a given amount of lateral movement).

[0082] In one embodiment, the spring adjuster 82 includes a fixed pinion 84 connected to at least one linear gear or rack 86 (or other linear actuator). Each linear gear 86 is connected to or engaged with a corresponding spring 34 to adjust the spring force f s For example, each linear gear 86 is attached at one end thereof to an interface member 88 (eg, a plate or disk) that engages the spring 34 .

[0083] Pinion 84 is connected to an actuator 90, such as a low power motor, which is operable to rotate pinion 84, thereby moving linear gear 86 and compressing or decompressing spring 34. Actuator 90 may be manually controlled by an operator, or controlled by controller 92 or other processing device.

[0084] Fig. 8A The battery cell 14 is shown as having expanded and exerting an expansion force Fe on the pressure plate 22. As described above, each mechanical linkage 24 is combined with a spring 34 or other biasing device to change the expansion force F e direction, and exerts a reverse force F on the battery cell 14 r In this case, the opposing force F r Having a first size.

[0085] If the reverse force needs to be adjusted (e.g., to maintain a constant pressure under conditions such as temperature changes, or to change the pressure), the pinion 84 can be controlled to rotate the pinion 84 and move the linear gear 86. The pinion 84 can be rotated clockwise to move the linear gear 86 outward and compress the spring 34, which increases the reverse force (e.g., the expansion force) relative to a given expansion force. Figure 8B In order to decompress the spring 34 and thereby reduce the reverse force, the pinion 84 can be rotated clockwise.

[0086] The embodiments are not limited to Fig. 8A and 8BConfiguration shown. Embodiments may include multiple spring force adjusters that are synchronously controlled by a single motor. In other embodiments, multiple independent spring force adjusters are provided, wherein each spring force adjuster is independently controlled.

[0087] Fig. 9A and 9B An example is shown where the adjustment system 80 includes two independently controllable spring adjusters 82a and 82b. Each spring adjuster is connected to a different spring 34 or biasing device and has its own motor. Fig. 9A The biasing system is shown in a first state, wherein the compression on the spring 34 is relatively low, Fig. 9B The state where both spring adjusters 82a and 82b are actuated to compress their respective springs 34 is shown. Since each spring adjuster is independently controllable, different amounts of compression can be applied (e.g., spring adjusters 82a and 82b are controlled so that one of the springs 34 has a different amount of compression than the opposing spring 34).

[0088] Fig.10 An embodiment of a method 100 of managing stress of a battery assembly is shown. Aspects of the method 100, such as adjustment of the biasing system, may be performed by one or more processors.

[0089] Method 100 includes a number of steps or phases represented by blocks 101-103. Method 100 is not limited to the number or order of steps therein, as some steps represented by blocks 101-103 may be performed in a different order than described below, or less than all steps may be performed in an order.

[0090] For ease of explanation, combined Figure 2A and 2B The pressure management system 20 shown discusses various aspects of the method 100. The method 100 is not limited thereto and may be used with any type of battery cell and any system having an opposing force linkage as described herein.

[0091] In block 101, a battery assembly is assembled or manufactured. The battery assembly may be a battery module having one or more battery cells, such as module 12. Such battery cells may be lithium metal pouch cells or any other battery that is susceptible to swelling. The manufacture of the battery assembly includes providing a pressure management system in the battery assembly, such as Figure 2A and 2B Stress management system 20.

[0092] In box 92, the battery assembly is operated. For example, the battery module 12 is the battery pack of the vehicle and provides power to one or more electric motors of the vehicle.

[0093] In block 93, the pressure management system controls the pressure of one or more cells of the battery pack when one or more cells expand during (or between) operations. This control includes applying a proportional opposing force in a direction toward the cell to compensate for the expansion force and maintain a desired pressure or pressure range. For example, when the battery cell 14 expands, the mechanical linkage 24 and the spring 34 apply the expansion force F e A portion of the force is redirected as a counter force F r .

[0094] In one embodiment, the pressure management system is a passive system that automatically reacts and applies an opposing force affected by the spring constant or stiffness of the biasing system. In another embodiment, if a spring adjuster is included, the control includes operating an actuator to adjust the spring force applied in response to movement of the linkage.

[0095] As described herein, a pressure management system may be coupled to, or be a part of, a vehicle battery system. Fig.11 An embodiment of a motor vehicle 110 is shown, which includes a body 112. The vehicle 110 can be an internal combustion engine vehicle, an electric vehicle (EV), or a hybrid electric vehicle (HEV). In one example, the vehicle 110 is a hybrid or electric vehicle having an electric motor 114. A battery system 116 is electrically connected to the electric motor 114 and / or other components, such as vehicle electronics. The battery system 116 includes one or more modules 12, and each module 12 defines a high-voltage battery pack or is part of a high-voltage battery pack.

[0096] The vehicle 110 also includes one or more processing devices, such as a controller 118. The controller 118 may perform various functions, such as controlling conversion devices (e.g., one or more inverters and / or one or more direct current (DC)-DC converters), controlling components of a battery management system (e.g., spring adjuster 82), and / or monitoring the motor 114 and / or the battery system 116, among others. The controller 118 may include processing circuitry that may include an application specific integrated circuit (ASIC), electronic circuitry, a processor (shared, dedicated, or group) and memory executing one or more software or firmware programs, combinational logic circuitry, and / or other suitable components that provide the described functionality. The controller 118 may include a non-transitory computer-readable medium storing instructions that, when processed by one or more processors of the controller 118, implement methods for operating vehicle components and systems as desired.

[0097] Fig.12Various aspects of an embodiment of a computer system 140 that can perform various aspects of the embodiments described herein are described. The computer system 140 includes at least one processing device 142, which typically includes one or more processors, for performing various aspects of the image acquisition and analysis methods described herein.

[0098] Components of computer system 140 include processing device 142 (such as one or more processors or processing units), memory 144, and bus 146, which connects various system components including system memory 144 to processing device 142. System memory 144 can be a non-transitory computer-readable medium and can include various computer system-readable media. Such media can be any available media that can be accessed by processing device 142, and includes volatile and non-volatile media, as well as removable and non-removable media.

[0099] For example, system memory 144 includes non-volatile memory 148, such as a hard disk, and may also include volatile memory 150, such as random access memory (RAM) and / or cache memory. Computer system 140 may also include other removable / non-removable, volatile / non-volatile computer system storage media.

[0100] The system memory 144 may include at least one program product having a set (e.g., at least one) of program modules configured to perform the functions of the embodiments described herein. For example, the system memory 144 stores various program modules that generally perform the functions and / or methods of the embodiments described herein. One or more modules 152 may be included to perform functions related to monitoring the battery system. An image analysis module 154 may be included to control aspects of pressure management, such as controlling an actuator of a spring adjuster as described herein. The system 140 is not limited in this regard, as other modules may be included. 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 grouped) and memory that executes one or more software or firmware programs, a combinational logic circuit, and / or other suitable components that provide the described functions.

[0101] The processing device 142 may also communicate with one or more external devices 156 (e.g., a keyboard, a pointing device, and / or any device such as a network card, a modem, etc.), which enables the processing device 142 to communicate with one or more other computing devices. Communication with various devices may be performed through input / output (I / O) interfaces 164 and 165.

[0102] The processing device 142 may also communicate with one or more networks 166, such as a local area network (LAN), a general wide area network (WAN), a bus network, and / or a public network (e.g., the Internet) via a network adapter 168. It should be understood that, although not shown, other hardware and / or software components may be used in conjunction with the computer system 40. Examples include, but are not limited to, microcode, device drivers, redundant processing units, external disk drive arrays, RAID systems, and data archiving storage systems, etc.

[0103] The terms "one" and "an" do not indicate a quantitative limitation, but rather indicate the presence of at least one of the referred item. The term "or" means "and / or" unless the context clearly indicates otherwise. References to "an aspect" 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 various aspects.

[0104] 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.

[0105] Unless otherwise specified 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.

[0106] 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 invention belongs.

[0107] 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 thereto and equivalent replacements may be made to its elements without departing from the scope thereof. In addition, many modifications may be made to adapt specific situations or materials to the teachings of the present disclosure without departing from the substantive scope of the present disclosure. Therefore, it is intended that the present disclosure is not limited to the specific embodiments disclosed, but will include all embodiments falling within its scope.

Claims

1. A stress management system, comprising: the pressure plate being disposed in an initial position relative to the battery cell, the battery cell being disposed in the housing, wherein expansion of the battery cell causes an expansion force to be applied to the pressure plate; a mechanical linkage connected to the pressure plate, the mechanical linkage configured to move in a lateral direction in response to an expansion force and to convert the expansion force into a reaction force opposing the expansion force; and A biasing system includes a biasing member configured to resist lateral movement of the mechanical linkage, the biasing system being configured to apply a biasing force in a direction opposite the lateral direction that causes the mechanical linkage to apply a reaction force that is a selected proportion of the expansion force.

2. The system according to claim 1, wherein: The biasing member has a spring constant selected such that the biasing force causes the reaction force to be a selected proportion of the expansion force.

3. The system of claim 1 , further comprising a stop member configured to limit lateral movement of the mechanical linkage, such that a portion of the lateral force generated by the mechanical linkage is directed toward the battery cell based on a reaction force generated by the stop member.

4. The system according to claim 3, wherein: The biasing member is a spring having a first end configured to be connected to the mechanical linkage and a second end connected to the stop component.

5. The system according to claim 1, wherein: The mechanical linkage device includes a pivot member having a first end and a second end, wherein the first end is connected to the pressure plate at a first pivot point, and the pivot member is configured to rotate about a fixed pivot point, wherein the fixed pivot point is located between the first end and the second end, and the fixed pivot point has a fixed position relative to the housing.

6. The system according to claim 5, wherein: The mechanical linkage includes a connecting member having a third end connected to the second end via a second pivot point and a fourth end movable in a lateral direction.

7. The system of claim 1, further comprising a bias control configured to be operated to adjust the biasing force of the biasing member.

8. The system according to claim 7, wherein: The bias control device includes a pinion connected to a linear gear, the pinion connected to an actuator, the actuator configured to rotate the pinion to adjust the bias force.

9. A method for controlling pressure of a battery cell, comprising: receiving an expansion force on a pressure plate disposed at an initial position relative to a battery cell disposed in the housing, the expansion force being generated by expansion of the battery cell; and Managing pressure in the battery cell by a pressure management system including a mechanical linkage connected to a pressure plate and a biasing system including a biasing member, wherein managing pressure includes: converting the expansion force into a reaction force configured to oppose the expansion force based on lateral movement of the mechanical linkage in a lateral direction; and The reaction force is controlled based on the lateral movement of the mechanical linkage being resisted by a biasing system that applies a biasing force in a direction opposite to the lateral direction via a biasing member, the biasing force causing the mechanical linkage to apply a reaction force that is a selected proportion of the expansion force.

10. The method according to claim 9, wherein: The pressure management system includes a stop member configured to limit lateral movement of the mechanical link such that a portion of the lateral force generated by the mechanical link is directed toward the battery cell based on a reaction force generated by the stop member.

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