Battery module with controlled hydraulics

Abstract

The present invention relates to an all-solid-state battery module having a housing that defines an internal cavity. At least one end cap closes access to the internal cavity. The end cap is attached to the housing. Multiple cells are present within the internal cavity, and these cells are immersed in a liquid contained within the internal cavity. The battery module is sealed so that the fluid acts isotropically on the multiple cells. This specification also relates to a method for controlling the operating pressure and temperature of the battery module.

Description

Technical Field

[0001] The present disclosure relates to battery modules and the management of battery operating pressure.

Background Art

[0002] Certain operating parameters enable the optimal use of battery cells such as all-solid-state batteries. According to current knowledge, accurate, active, and dynamic management of the operating pressure value and temperature value of a battery tends to be important for the following purposes: minimizing or eliminating the generation of dynamic pores or "voids" during rapid discharge (the "stripping" phase) that promotes the formation of dendrites during subsequent rapid charging; increasing the charging rate while limiting or eliminating the formation and propagation of dendrites during plating; increasing battery life (capacity maintenance, minimizing inactive lithium); suppressing the rate of increase in the impedance of battery cells over cycles; work-hardening the areas / tips of dendrites (increasing the diffusion / transport of lithium or other metals constituting the negative electrode); ensuring that the contact quality at the interface of the positive electrode - electrolyte - negative electrode of the cell is maintained; minimizing or eliminating damage to the cell during the occurrence of abnormal stress; and / or maximizing the potential of next-generation batteries.

[0003] On the other hand, the presence of dynamic management systems can reduce overall efficiency due to their energy consumption, volume, weight, and further due to the need to consider the costs associated with those systems.

Summary of the Invention

[0004] An object of the present disclosure is to propose a simplified system for managing the operating pressure and temperature of a battery.

[0005] According to a first aspect of the present disclosure, a battery module is provided, comprising a housing defining an internal cavity and a plurality of cells within the internal cavity, wherein the plurality of cells are immersed in a fluid contained within the internal cavity, the plurality of cells are designed to be connected to an electrical circuit, the battery module is airtightly sealed such that the fluid exerts isotropic pressure on the plurality of cells, and the mass of the fluid within the battery module is kept constant while the battery module is used in a sealed mode.

[0006] In this first embodiment, for example, at least one Peltier effect module is in contact with the housing, and the Peltier effect module is activated to selectively heat or cool the fluid contained within the internal cavity.

[0007] Furthermore, in the first embodiment, for example, the Peltier effect module has fins on its free surface.

[0008] Furthermore, in the first embodiment, for example, there is at least one compression element between at least two adjacent cells.

[0009] Furthermore, in the first embodiment, for example, at least one resistive element is present within the internal cavity for heating the fluid.

[0010] Furthermore, in the first embodiment, for example, at least one finned plate is in contact with the housing.

[0011] Furthermore, in the first embodiment, for example, at least one pump is present within the internal cavity of the housing for circulating the fluid.

[0012] Furthermore, in this first embodiment, for example, the fluid is oil.

[0013] A second aspect of the present disclosure provides a battery system comprising at least one battery module as described below and a control system, the control system comprising at least one processor and a computer-readable memory storing commands to be executed by the at least one processor, the commands being commands for monitoring the temperature and / or pressure of the at least one battery module and commands for initiating cooling or heating of the battery module when the temperature and / or pressure of the module is outside a predetermined range, while maintaining a constant mass of the fluid in the battery module and hermetically isolating the battery module from the addition and removal of the fluid when the battery module is in use.

[0014] In this second embodiment, for example, at least two battery modules are provided, and the two battery modules have characteristics defined by different pressure-temperature curves.

[0015] Furthermore, in this second embodiment, for example, the curves have different slopes.

[0016] Furthermore, in this second embodiment, for example, the curves have different pressure values ​​at the same temperature.

[0017] Furthermore, in the second embodiment, for example, a housing is provided for each battery module, and the housing defines a convection path for controlling the temperature of the battery module.

[0018] Furthermore, in this second embodiment, for example, the housings are connected in series to form a continuous convection path.

[0019] Furthermore, in this second embodiment, for example, there is at least one valve between the two housings.

[0020] Furthermore, in this second embodiment, for example, the housings are arranged in parallel.

[0021] Furthermore, in this second embodiment, for example, each housing has a valve on the downstream side of the convection path.

[0022] Furthermore, in this second embodiment, for example, a fan is present upstream of at least one of the convection paths of the housing.

[0023] A third aspect of the present disclosure provides a method for controlling the operating pressure and / or temperature of at least one battery module, the method comprising: housing a plurality of battery cells in an internal cavity of at least one battery module, the internal cavity being airtightly sealed, and the plurality of battery cells being immersed in a fluid; monitoring the temperature and / or pressure of the module; and, when the battery module is in use, cooling or heating the module if the temperature and / or pressure of the module is outside a predetermined range, while maintaining a constant mass of the fluid within the battery module and airtightly isolating the battery module from the addition and removal of the fluid.

[0024] In this third embodiment, for example, the step of cooling or heating the module is performed by activating the Peltier effect module by controlling the direction of the current.

[0025] A further aspect of the present disclosure provides a method for controlling the operating pressure and temperature of a battery module, the method comprising: housing a plurality of battery cells in an internal cavity of the battery module, wherein the internal cavity is airtightly sealed and the plurality of battery cells are immersed in a fluid; monitoring the temperature and / or pressure of the module; and, when the battery module is in use, cooling or heating the module if the temperature and / or pressure of the module deviates from a predetermined value.

[0026] In connection with this description, the accompanying drawings are referred to.

Brief Description of the Drawings

[0027] [Figure 1] FIG. 1 is a system including a battery module designed according to an embodiment of the present disclosure.

[0028] [Figure 2] FIG. 2 is a perspective view of a battery module designed according to the present disclosure in a state where the end cap is removed and the cell is partially removed from the housing.

[0029] [Figure 3] FIG. 3 is a perspective view of the battery module of FIG. 2 in a state where the end cap is removed and the cell is completely installed in the housing.

[0030] [Figure 4] FIG. 4 is a perspective view of a battery module in a state where the end cap is attached to the housing.

[0031] [Figure 5] FIG. 5 is an exploded perspective view of the housing of the battery module of FIG. 1 with the end cap.

[0032] [Figure 6] FIG. 6 is a perspective view of a series of cells of the battery module of FIG. 2 according to an embodiment.

[0033] [Figure 7] FIG. 7 is a front view of the cell of FIG. 6.

[0034] [Figure 8] FIG. 8 shows a battery having a different geometry from the battery module of FIG. 2.

[0035] [Figure 9] Figure 9 shows the cells of the battery module shown in Figure 8.

[0036] [Figure 10] Figure 10 is a front view of the battery module cell shown in Figure 8.

[0037] [Figure 11] Figure 11 is a partial view of a Peltier effect modular heating / cooling system, which may be used in the housing of the battery module shown in Figure 2, according to one embodiment.

[0038] [Figure 12] Figure 12 is an end view of the battery module of Figure 2, which has a Peltier effect modular heating / cooling system similar to that of Figure 11.

[0039] [Figure 13] Figure 13 is another end view of the battery module of Figure 2, which includes a Peltier effect modular heating / cooling system and passive heat sink fins for the housing.

[0040] [Figure 14] Figure 14 is a perspective view of a housing with a heating element.

[0041] [Figure 15] Figure 15 is a schematic diagram of the housing for the battery module shown in Figure 2.

[0042] [Figure 16] Figure 16 is a perspective view of the three enclosures used together, each incorporating one of the battery modules shown in Figure 2.

[0043] [Figure 17] Figure 17 is a graph showing the pressure-temperature curves at different starting pressures for three battery modules following Figure 2.

[0044] [Figure 18] Figure 18 is a graph showing the pressure-temperature curves for three battery modules according to Figure 2, using different housing materials.

[0045] [Figure 19] Figure 19 is a graph showing the pressure-temperature curves for three battery modules according to Figure 2, using different compression materials and / or different housing materials.

[0046] [Figure 20] Figure 20 is a graph showing the change in fluid pressure as a function of temperature for a battery module according to this disclosure, which includes a Peltier effect module.

[0047] [Figure 21] Figure 21 is a graph showing the changes in fluid pressure and temperature as a function of time in a first test of a battery module according to the present disclosure, which includes a Peltier effect module.

[0048] [Figure 22] Figure 22 is a graph showing the changes in fluid pressure and temperature as a function of time in a second test of a battery module according to the present disclosure, which includes a Peltier effect module.

[0049] [Figure 23] Figure 23 is a graph showing the change in fluid pressure as a function of temperature for a battery module according to this disclosure, which includes a Peltier effect module, with and without a compression member. [Modes for carrying out the invention]

[0050] Referring to the drawings, particularly Figure 1, a system for the use and control of a battery according to this disclosure is indicated by the reference numeral "1". System 1 comprises three battery modules 10 as described below, but System 1 may contain more than three or fewer than three battery modules 10. In one embodiment, a battery module 10 may be described as a solid-state battery capable of controlling pressure and / or temperature, particularly by utilizing the Peltier effect. A battery module 10 may also be used as an electrolyte battery, such as a solid-state battery, liquid battery, or hybrid battery. A battery module 10 may also be identified as a battery, cell module, etc. The battery modules 10 of System 1 may have different operating characteristics according to the configurations described in particular in Figures 17 to 19. As will be described later, System 1 differs from certain dynamic systems that control pressure and / or temperature by changing the mass of oil in the battery module 10 during operation. System 1 is characterized by its ability to operate in a sealed mode while simultaneously allowing control of pressure and / or temperature within the battery module 10, while maintaining a constant mass of fluid (e.g., oil) within the battery module 10 during operation. When referring to the operation of System 1, this means charging the battery and / or using the battery to supply energy demands. Pressure and / or temperature fluctuations may be related to several factors, such as charging, discharging, ambient conditions of the battery environment, and cooling. The system in Figure 1 shows various battery management modules, e.g., a battery management system (BMS), a temperature control subsystem having a temperature control module with thermocouples or other temperature measuring devices, a temperature adjustment module based on a setpoint, etc. Thus, the battery management system comprises at least one processor and a medium or memory readable by the processor and containing machine instructions. The medium and / or readable memory stores descriptions and instructions that are to be executed by a computer to perform the temperature control method described herein.The direction of current flowing to the Peltier effect module can be reversed by the battery management system (BMS) to heat or cool the battery module.

[0051] In the context of this disclosure, a battery or battery module 10 comprises a plurality of cells, each consisting of two electrodes (a positive or anode and a negative or cathode) separated by a medium (called an electrolyte) that functions as an ion conductor. The plurality of cells may have various structures, forms, and dimensions. The anode, cathode, and electrolyte may be manufactured from various materials. The electrolyte may be liquid, solid, or hybrid (polymer, ceramic, liquid, etc.). An all-solid-state battery is, among other things, one embodiment. The plurality of cells are connected to an electrical circuit for use.

[0052] In Figure 2, the battery module 10 is shown in an exploded view. The battery module 10 comprises a housing 20 (i.e., a tubular element) designed to house a plurality of cells 30. Onboard circuitry is connected to the plurality of cells 30 and can control their operation and monitor their charge state. The onboard circuitry may include a power supply unit, energy sink, current limiter, and smart charger (not shown) that generate relevant pressure, temperature, and current density conditions to achieve optimal performance of the battery module 10. Such (these) onboard circuits may be located inside or outside the module. End caps 40 (i.e., end members) are present at both ends of the housing 20 to seal the inside of the battery module 10. The battery module 10 may optionally also include a heating element such as the Peltier effect module 50 shown in Figure 11 or the resistive element 50' shown in Figure 14, and a pump 60 shown in Figure 14. The battery module 10 may be housed in a housing 70 as shown in Figure 16. Multiple cells 30 are immersed in a fluid held by the housing 20. This fluid may be a liquid, preferably an oil, more preferably a mineral oil, and serves to neutralize any chemical reactions that may occur if the cells are defective or damaged. This neutralization is due, in particular, to the chemical properties of the fluid, oxygen deficiency around the cells, and / or the application of isotropy based on an incompressible fluid. In particular, the use of oil can prevent combustion caused by chemical reactions in defective cells by isolating them from the surrounding oxygen.

[0053] In the embodiment shown in Figure 2, the housing 20 has a cylindrical hollow body 21. The cylindrical shape is illustrated by the outer surface 21A of the hollow body 21. The outer surface 21A may be a smooth cylindrical shape, or it may have other surface features such as the heat dissipation fins 21B shown in Figure 13.

[0054] The housing 20 also defines an internal cavity 22 (i.e., a chamber) defined by its inner surface 22A. The internal cavity 22 may be cylindrical in shape, or it may have other features on its inner surface 22A, similar to the outer surface 21A, to provide the embodiments described later. Optionally, flanges 23 are positioned at both ends of the hollow body 21. The flanges 23 are of the radially projecting type. Holes 23A may be provided on the periphery of the flanges 23 to allow end caps 40 to be fixed to the housing 20. Various other features may be provided, such as seals to ensure that fluids (i.e., oil) inside the battery module 10 remain there (do not leak to the outside).

[0055] The housing 20 receives a plurality of cells 30 within its internal cavity 22. Each cell 30 may have a body 31 containing a chemical storage element. As shown in Figure 7, the body of the cell 30 may be in the form of a bag. Connectors 32 are located at both ends of the body 31 and are used to connect electrodes and / or to connect the cells 30 to each other. As shown in Figure 3, some cells may be separated by a compression member 35. The compression member 35 is, for example, a plate with different compression ratios, enabling the design of a battery module 10 with a desirable relationship of increasing pressure with increasing temperature, as shown in Figure 19, which will be described later. The compression member 35 is optional and can take various forms. In particular, as an example, the compression member 35 may be an elastomer foam panel, a bubble wrap sheet, etc. Electrical connection configurations, pads 36, and other components may be provided to hold the cells 30 in place, to connect them to an electrical circuit, or to space them apart. These components may be similar to those presented in the international patent application PCT / CA2022 / 051538, filed on 19 October 2002. The contents of that application are incorporated by reference into this patent application.

[0056] In Figures 2 to 5, the end cap 40 is illustrated to have a hemispherical or dome-shaped closure 41. Other geometric shapes are also considered. The closure 41 has a hemispherical outer surface 41A. Due to the three-dimensional shape of the closure 41, the end cap 40 may have an internal cavity 42 (Figure 5) defined by its inner surface 42A. This internal cavity 42 can be in fluid communication with the internal cavity 22 of the housing 20. However, a plate (partition) may be used on at least one side of the end cap 40 to form an isolation chamber. This isolation chamber can, in particular, house electronic components that should not be immersed in the fluid of the housing.

[0057] A flange 43 may project radially from the closure 41. The flange 43 may have a similar geometry to the flange 43 of the housing 20. Holes 43A are circumferentially arranged on the flange 43 to allow the use of fasteners such as screws and bolts to secure the end cap 40 to the housing 20. For example, these fasteners are shown as reference numeral 43B in Figure 5. Ports 44 may be provided at the end of the end cap 40 or at other locations. The ports 44 allow the injection of fluid into the housing 20. In Figures 3 and 4, ports 44 can be seen at both ends of the battery module 10. These ports 44 are fluid inlets and / or fluid outlets and may, in particular, allow gas to be discharged when, for example, oil is filled into the battery module 10. The ports 44 may include valves or any other form of plugs that allow the injection and subsequent discharge of liquid into and out of the battery module 10 while sealed during use. Ports 44 may also be located at other locations, such as on the housing 20. Port 44 may include a safety valve that vents oil or gas if the pressure inside module 10 exceeds the maximum design value. As shown in Figure 5, a compression member 45 may be positioned on one or both of the end caps. The compression member 45 may be a bushing with a given elasticity. The compression member 45, like the compression member 35, contributes to pressure control inside the battery module 10. Even if port 44 is present in battery module 10, port 44 may be closed while the battery module is operating, so the mass of fluid inside battery module 10 does not fluctuate during use. Battery module 10 is in sealed mode, and the fluid inside battery module 10 does not leave the housing during use during charging / discharging, nor is any fluid added to the housing during this sealed mode. Battery module 10 is hermetically isolated from the addition and removal of fluid. However, under certain circumstances, particularly due to leaks or filling, there may be an addition or loss (increase or decrease) of fluid mass, but such fluctuations may be negligible and do not constitute a method by which System 1 regulates its temperature and / or pressure.

[0058] Therefore, the battery module 10 includes a plurality of cells 30 arranged in a row, as shown in Figure 6. The plurality of cells 30 can be inserted into a hollow body 21 to fill the housing 20. Compression members 35 may be present between some of the cells 30.

[0059] While a cylindrical housing shape is advantageous for a pressure vessel, it is also possible to use a housing 20 with a different shape. In the examples shown in Figures 8 to 10, the housing 20 has a prismatic shape. To allow comparison between the battery modules in Figures 2 to 7 and those in Figures 8 to 10, the same reference numerals are used for components that have the same function despite the existence of geometric differences.

[0060] The multiple cells 30 may be circular or square, but a configuration with two stacks of rectangular cells 30 is also conceivable, as shown in Figures 9 and 10. Thus, the multiple cells 30 in Figures 9 and 10 have an elongated body portion 31 with connectors (indicated as reference numeral 32) at both ends. Compression members 35 may be present between some of the cells 30. Thus, two or more stacks of cells 30 may be arranged in parallel, as shown in Figure 8. The end caps 40 in Figure 8 are flat rather than hollow. Figures 8 to 10 are just one solution.

[0061] Figure 11 shows a Peltier effect module 50. This Peltier effect module 50 can be optionally used in various battery modules 10 described herein. The Peltier effect module 50, also known as a Peltier effect modular heating / cooling system, converts electric current into a temperature difference. The direction of the current supplied to the Peltier effect module 50 can be reversed depending on whether it is heating or cooling. Thus, the Peltier effect module 50 may have two surfaces, one cold and the other hot. Here, the terms "cold" and "hot" are used in a relative sense. According to one embodiment, the Peltier effect module 50 is designed from a series of semiconductor pairs. The electrons of these pairs act as a heat transfer fluid. According to one embodiment, the surfaces (the two faces) are ceramic (or other material) plates separated by, for example, semiconductor pellets. In Figure 11, the Peltier effect module 50 has a surface 50A, which has a shape corresponding to the shape of the outer wall 21A of the hollow body 21 of the housing 20, and the two surfaces are in contact for heat conduction. This makes it possible to heat or cool the fluid in the internal cavity 22 by supplying current to the Peltier effect module 50. The shape is part of a cylindrical surface, but other shapes are also possible, especially if the housing 20 is prismatic. The surface 50A may be, for example, flat. It is also possible that the wall of the housing, or a part of the wall, is (functions as) a Peltier effect module. Optionally, fins 50B may be provided on the opposite surface of the Peltier effect module 50 to contribute to heat exchange with the surrounding environment of the module 10. By passing an electric current through the Peltier effect module 50, particularly via the cable 50C, the fluid in the internal cavity 22 can be heated by heat conduction through the surface 50A of the Peltier effect module 50 that is in contact with the outer wall 21A of the hollow body 21 of the housing 20. Due to the thermal expansion effect of the fluid, the internal pressure of the housing 20 increases. By reversing the direction of the electric current through the Peltier effect module 50, the fluid in the internal cavity 22 can be cooled by the surface 50A of the Peltier effect module 50 that is in contact with the outer wall 21A of the hollow body 21 of the housing 20.The direction of the current can be controlled by the BMS. Due to the thermal expansion (or contraction) of the fluid, the internal pressure of the housing 20 decreases. As shown in Figures 12 and 13, the Peltier effect module 50 can employ various distributions and configurations depending on the desired effect. Figure 11 shows a Peltier effect module 50 with four fins 50B, but these fins 50B are optional and may be fewer than four or more than four. In the embodiment of Figure 12, the housing 20 is surrounded, as an example, by eight of the Peltier effect modules 50 of Figure 11. In Figure 13, passive heat dissipation fins 21B are optionally present in combination with the Peltier effect module 50. These passive heat dissipation fins 21B may be formed directly on the outer wall 21A of the housing 20, or they may have a geometry similar to that of the Peltier effect module 50, etc., and may have a surface that conforms to the housing 20 and fins in the radial or other directions.

[0062] In Figure 14, the heating element 50' is located inside the battery module 10. The heating element 50' is illustrated as a resistive element strip. It may be considered to install these in specific parts of the housing 20 to assist in heating the fluid in the internal cavity 22. These heating elements 50' may be installed on the outer surface of the housing 20 and / or inside the walls of the housing, etc.

[0063] Figures 15 and 16 show the housing 70. The housing 70 defines an internal volume 70A in which the battery module 10 is positioned. This internal volume 70A serves as a convection path. Each housing 70 is provided with an intake valve 71 and exhaust valves 72A and 72B, and a fan 73 can bring about air movement inside the housing 70. The intake valve 71 and exhaust valves 72A and 72B can be arranged so that air circulates in series within housings 70 arranged in parallel. In particular, some of the exhaust valves 72A may be configured to discharge air to the outside, while the other exhaust valves 72B may be configured to allow air to circulate between housings 70. This is optional. The housing 70 allows for the recovery of cold or hot air generated from the module by convection, whether or not it is forced convection. This hot or cold air is either discharged to the outside or recirculated to other housings to contribute to the heating or cooling of adjacent modules. The configuration in Figure 16 shows two types of housings, allowing for series air circulation between the housings 70. The housings 70 can be used in parallel with each other, for example, each housing 70 may have its own fan 73. The control of valves 71, 72A, and 72B can be implemented to suit the optimal operating pressure of different modules 10, as shown in Figures 17 to 19. The housings 70 are shown in parallel with a meandering convection path, but other arrangements are also considered, particularly depending on the available space. For example, the housings 70 can be arranged with their ends aligned and / or stacked vertically.

[0064] While various embodiments of the battery module 10 are described, the control of the pressure and / or temperature of the battery module 10 is described here. The present disclosure aims to construct a system 1 (Figure 1) that enables the adjustment of the pressure of the fluid inside the module 10 while controlling only the temperature of the fluid. In other words, system 1 (Figure 1) enables the adjustment of the pressure of the fluid inside the module 10 using only electrical energy for cooling or heating the module 10. This adjustment can be performed while keeping the mass of the fluid inside the module 10 constant. That is, the module 10 is sealed and does not change the fluid content during operation and temperature control. System 1 can be operated by monitoring only the temperature of the module 10. This may be called the sealed operating mode of the battery module 10, in which no intentional addition or removal of fluid (e.g., oil) is made from the housing. This control is based on the fact that the thermal expansion of oil or other pressurized fluid sealed in a constant volume in an airtight storage container (reservoir) results in an increase in the pressure inside the storage container as the temperature of the oil rises. The relationship between the rise in fluid temperature and the rise in pressure within a storage container (e.g., a housing 20 with end caps 40) that is sealed in an airtight mode and does not manipulate changes in fluid mass is quasi-linear, depending on the thermal expansion coefficient and bulk modulus of the oil.

[0065] By using multiple battery modules 10 within the same system (e.g., system 1), it is possible to design modules 10 with different pressure change profiles with respect to temperature (nonlinear or linear with different slopes), thereby enabling the construction of a system 1 in which each battery module 10 has its own unique performance characteristics and complements the others as needed. Such simplification of pressure control may eliminate the need for several subsystems, resulting in improved energy density (Wh / l) and specific energy (Wh / kg) of the modules 10. This can be achieved by designing / using multiple modules 10 with the same or different chemical compositions in parallel. They may have complementary performance characteristics. The multiple modules 10 could be a cryogenic module, a power module, an energy module (autonomous), a sacrificial module, etc.

[0066] Referring to Figure 17, graphs showing the pressure curves as a function of temperature for three different modules 10 are provided. These modules 10 have identical sealed reservoirs (in terms of volume and shape) and are manufactured from the same material. The pressure profile as a function of temperature is identical (same slope) for all three modules 10. Therefore, three different battery modules 10 can be designed, for example, by setting the pressure of module 10 to different initial values ​​at the initial operating temperature (e.g., 25°C).

[0067] Figure 18 shows another graph illustrating the pressure curve as a function of temperature for three different modules 10. These modules 10 have identical sealed reservoirs (in volume and shape) but are manufactured from different materials (e.g., magnesium, aluminum, steel, etc.). The pressure profiles as a function of temperature are not identical (they have different slopes). Therefore, three different battery modules 10 can be designed by setting the pressure of module 10 to the same initial value, for example, at the initial operating temperature (e.g., 25°C). This approach is based on the Young's modulus of the material. Young's modulus defines the amount of plastic deformation of the material as a function of the stress it experiences (here, the internal pressure of the storage container, i.e., the housing 20). Materials with a very high Young's modulus are said to be highly rigid. A housing 20 made of standard aluminum (Young's modulus 69 GPa) will deform more than a similar housing 20 made of stainless steel (Young's modulus 203 GPa) when subjected to the same operating pressure. The pressure exerted on the aluminum housing 20 by the expanding oil (temperature rise) increases more slowly because the volume of the housing 20 increases slightly under that pressure (deformation of the aluminum). Similarly, the magnesium (Young's modulus 45 Gpa) housing 20 deforms more significantly when subjected to the same operating pressure as a similar standard aluminum (Young's modulus 69 Gpa) housing.

[0068] Figure 19 shows yet another graph illustrating the pressure curve as a function of temperature for three different modules 10. These modules 10 may have identical sealed reservoirs (in volume and shape) and be manufactured from the same material. However, a portion of the internal volume is composed of different compressible materials (type and / or quantity), for example, in the form of compression members 35 and / or 45. As a result, the pressure change profiles as a function of temperature are not identical (they have different slopes). Thus, three different battery modules 10 can be designed, for example, by setting the pressure of module 10 to the same initial value (or different values) at the initial operating temperature value (e.g., 25°C). This approach is based on the bulk modulus of the material 35 and / or 45 inserted into the internal cavity of the housing 20 (which may include the inside of the end cap 40 for the compression members 45). The compression members 35 and / or 45 may be in the form of small pieces of elastomer, foam, or other more or less compressible material, and may be in larger or smaller quantities. These compression members 35 and / or 45 can deform more or less under the fluid pressure within module 10, depending on their isotropic modulus (or compressibility). This results in different pressure rise rates as a function of temperature, depending on the differences between the compression members 35 and / or 45. This approach can be defined by the ability to design a storage container (i.e., housing) having a so-called global Young's modulus (GYM), determined by the Young's moduli of all the components of module 10.

[0069] Figures 20 to 23 show various graphs illustrating the pressure and temperature of the battery module 10 under various operating conditions, as non-limiting examples. Figure 20 is a graph showing the pressure against temperature for a battery module according to this disclosure, provided with an aluminum housing 20 as one embodiment, which includes a Peltier effect module of type indicated by reference numeral 50. The Peltier effect module 50 was activated to heat and then cool the battery module 10. Figures 21 and 22 show the pressure and temperature resulting from heating and cooling by the activation of the Peltier effect module 50 in the aluminum housing 20 in tests at different starting temperatures and pressures. Finally, Figure 23 shows the pressure against temperature for an aluminum or steel battery module 10 with and without a compression member such as reference numeral 35, activated by the Peltier effect module 50. It can be seen that the compression member 35, such as bubble wrap or foam, can modify the rate of change of the fluid pressure in the battery module 10 as a function of temperature.

[0070] Once the design of the battery module 10 is established, the rate of pressure change as a function of temperature change can be fixed (constantized) and made predictable. Therefore, it is necessary that the temperature inside the battery module 10 can be effectively adjusted (controlled). The quality of a temperature control system effective for such applications may include the following: • Percentage change of operating temperature (°C / second) • Temperature uniformity across the entire surface area of ​​cell 30 in module 10 • Energy consumption of System 1 • Volume and weight of System 1 (specific energy and energy density of the module) • Complexity of System 1 and its peripheral systems • Robustness • Safety in the event of an accident, malfunction, short circuit, or thermal runaway.

[0071] Furthermore, specific contextual factors regarding the chemical properties of all-solid-state batteries must be considered. Currently, polymer electrolytes are considered to require lower operating pressures than ceramic electrolytes (e.g., 200 psi vs 900 psi). Therefore, the battery module 10 needs to accommodate a fairly wide pressure range. Higher operating temperatures (above 30°C), while considering material properties and safety, promote better performance of the cells 30. At low temperatures (e.g., 0°C), the battery module 10 is unusable or performs at a very low level. While considering material properties and safety, it is acknowledged that higher operating pressures promote better performance of the cells 30 or do not affect the performance of the cells 30. During operation, the cells 30 within the module 10 generate heat. This heat can be used to warm the oil in the module 10 in which the cells 30 are located. This heat can also be recovered to heat the oil in another module 10. Therefore, according to one embodiment, module 10 is heated, for example, by a heat-generating element 50 and operates at a higher pressure. Thus, the main pressure regulation function can be based on heat dissipation to other modules 10 or heat dissipation to the outside of module 10.

[0072] Various embodiments can be implemented to manage the pressure and temperature within the battery module 10, either individually or in groups. In particular, to equalize the temperature of the cells 30, the circulation of oil can be induced within the module 10 for heat exchange with the cells 30. One approach is to heat the oil from the bottom of the housing 20 (e.g., Figure 14, heating element 50). The hot oil, being less dense than the cold oil, moves upward due to gravity and circulates through the gaps separating the cells 30. Similarly, the cells are cooled from the top of the housing 20, causing the cold oil to move downward. In particular, the heat dissipation fins 21B in Figure 13 and external convection on the housing 20 can contribute to the cooling of the oil. Oil circulation can be forced, for example, by a pump 60 (Figure 14) located within the housing 20, and oil circulation over the cell 30 can be forced by conduits that promote optimal heat exchange, but during operation, in airtight mode, the mass of fluid within the module 10 does not change. In addition to the various systems (devices) described above, such as the Peltier effect module 50 and the heat-generating element 50', other means can also be used to heat or cool the battery module 10. For example, the battery module 10 can be heated and / or cooled by a pipe-type external refrigeration system using a refrigerant, particularly used as a heat pump. The refrigerant pipes are in contact with the housing 20. Another example of a refrigeration system using a Carnot cycle can be realized by an external heating system using a heat transfer fluid such as water or glycol circulating in pipes surrounding the housing 20 of one or more modules 10, etc. In another example, the refrigeration system uses a heat transfer circuit with a heat sink (e.g., ambient convection from a radiator for a moving vehicle) without using a Carnot cycle. These are just examples of methods for controlling the temperature of the module 10.

[0073] The heat generated by the cell 30 itself can also contribute to temperature control. The heat generated by the operating cell 30 is used to heat the oil, and the pressure of module 10 is adjusted accordingly. System 1 may include multiple modules 10, and heat recovery from a module 10 that has reached its operating temperature may be used to assist in heating other modules 10. The housing 70 or other conduits may play a role in trapping heat and directing it to other housings to heat modules 10 within those other housings. Fans may be used to force convection and heat dissipation to other modules 10 that require heat.

[0074] System 1 may be provided with one or more Peltier effect modules 50. Such a module 50 has one surface in contact with the wall of the housing 20 and the other surface exposed to the ambient environment. In a heat dissipation scenario, power may be supplied to the Peltier effect module 50 so that the cold side is in contact with the wall of the housing 20 and the hot side faces outwards from the housing 20.

[0075] These configurations can be combined in various ways depending on the needs of System 1.

[0076] Overall, System 1 can be controlled based on specific considerations. In terms of regulating the temperature of the oil in which the cell 30 is immersed, the heat generated by the cell 30 during operation can be recovered or removed. It is generally advantageous for solid-state batteries to operate at the highest possible temperature, within limits defined by the properties of the materials constituting the cell. At low ambient temperatures (e.g., 0°C), it is advantageous to retain this heat for optimal operation of the cell 30, or to recover this heat from module 10, allowing the temperature of another module 10 to rise. At high ambient temperatures (e.g., 45°C), the cell 30 of the solid-state battery becomes more efficient / effective.

[0077] The housing 20 of module 10 includes a cell 30, a fluid such as oil, and the aforementioned oil heating / cooling system. The latter is located inside or outside the housing 20.

[0078] For the purpose of heat recovery and heat exchange between various modules 10, multiple modules 10 may be arranged within a housing 70 and isolated from one another. The multiple housings 70 communicate with each other as needed, depending on the temperature. Therefore, the heat exchange system between various modules 10, particularly via the housing 70, aims to optimally utilize the heat naturally generated by a cell 30 during its operation. The heat generated by the cell 30 can be stored within the module 10, redistributed to another module 10, or discharged from the system 1.

[0079] A device for cooling the oil (e.g., Peltier effect module 50, fins 21B, housing 70, etc.) or a device for heating the oil (heating element 50', Peltier effect module 50) is used when the operating parameters of the battery suggest that the conditions naturally generated by the system (including ambient temperature parameters) do not allow for optimal battery operation. Despite heating and cooling, system 1 maintains a constant mass of oil in the battery module 10. This may be called sealed-mode battery operation.

[0080] Accordingly, the housing 70 defines a sealed structure provided with valves that can be positioned in an open or closed position. These are controlled by a control system managed by the BMS battery management system, for example, via actuators such as solenoids. These valves 71, 72A, and 72B allow the inflow of external air into the housing 70, the discharge of air to the outside of the housing 70, or the discharge of air to the housing 70 incorporating an adjacent module 10. Each valve may correspond to a aligned opening in an adjacent module.

[0081] To enable efficient heat exchange by convection, a fan may be installed at the end of the housing 70. To enable efficient movement of air from one housing 70 to another, various models of the housing 70 may be used. Thus, according to FIG. 1, the air discharged from the housing 70 is either hot or cold. One effective example of a possible module configuration (Module 1, Module 2, Module 3) may include a method in which hot air from the housing is discharged to an adjacent module (T° Module 1 < T° Module 2 < T° Module 3). By this method, the system design results in three complementary modules 10. These may be based on cells of different chemical compositions and / or on modules 10 having different functions (e.g., energy vs. power) and / or on modules having different pressure change profiles as a function of temperature. Thus, as particularly shown in FIGS. 17 to 19, they may be specialized for different functions.

[0082] Thus, the system 1 is simple in that it performs heating and / or cooling while maintaining a constant oil mass in a closed mode, and by controlling only the temperature of the fluid confined within the module 10 (i.e., during operation, there is no addition or removal of oil), both the operating temperature of the cell 30 and the fluid pressure within the module 10 can be adjusted. Thus, if desired, the system can operate without using a mechanical or other pressure system, a cell cooling system, a pump, a valve, a storage container, etc. Further, the oil in which the cell 30 is immersed serves to neutralize / delay / prevent chemical reactions occurring within the cell 30 in case of failure.

[0083] Accordingly, the battery module 10 can be defined as comprising a housing defining an internal cavity and at least one end cap (which may be fixed to the housing and is optional) that closes access to the internal cavity. Multiple cells are located within the internal cavity and immersed in a liquid contained within the internal cavity. The battery module is hermetically sealed, and the fluid exerts isotropic pressure on the cells. A fluid with a very high compressive modulus (oil to air) can be said to be incompressible. In contrast to so-called compressible fluids, incompressible fluids that exert isotropic pressure on battery cells can have a favorable effect on the performance and safety of use of the battery cells. A battery system may comprise at least two battery modules. These two battery modules differ in characteristics defined by their pressure curves as a function of temperature. In particular, they have different slopes of the curves and / or different pressure values ​​at the same temperature.

[0084] The disclosure also provides a method for controlling the operating pressure and temperature of a battery module. The method comprises the steps of: housing a plurality of battery cells in an internal cavity of a battery module, wherein the internal cavity is airtightly sealed and the plurality of battery cells are immersed in a fluid; monitoring the temperature and / or pressure of the module; and, when the battery module is in use, cooling or heating the module if the temperature and / or pressure of the module is outside a predetermined range.

Claims

1. It is a battery module, A housing that defines the internal cavity, Multiple cells within the aforementioned internal cavity, Equipped with, The plurality of cells are immersed in the fluid contained within the internal cavity, The aforementioned multiple cells are designed to be connected to an electrical circuit, The battery module is hermetically sealed so that the fluid applies isotropic pressure to the plurality of cells. While the battery module is used in sealed mode, the mass of the fluid within the battery module is maintained constant. A battery module characterized by the following features.

2. At least one Peltier effect module in contact with the housing Furthermore, The Peltier effect module is activated to selectively heat or cool the fluid contained within the internal cavity. The battery module according to feature 1.

3. The Peltier effect module has fins on its free surface. The battery module according to feature 2.

4. at least one compression element between at least two adjacent cells A battery module according to any one of claims 1 to 3, further comprising the above.

5. At least one resistive element in the internal cavity for heating the fluid A battery module according to any one of claims 1 to 4, further comprising the above.

6. At least one finned plate in contact with the housing A battery module according to any one of claims 1 to 5, further comprising the above.

7. At least one pump in the internal cavity of the housing for circulating the fluid A battery module according to any one of claims 1 to 6, further comprising the above.

8. The fluid is oil. A battery module according to any one of features 1 to 7.

9. It is a battery system, A battery module according to any one of claims 1 to 8, Control system and, Equipped with, The control system is At least one processor, A computer-readable memory storing instructions to be executed by at least one of the processors, It has, The aforementioned instruction is, A command for monitoring the temperature and / or pressure of the at least one battery module, and When using the aforementioned battery module, a command is issued to initiate cooling or heating of the module if the temperature and / or pressure of the module are outside a predetermined range, while maintaining a constant mass of the fluid within the battery module and hermetically isolating the battery module from the addition and removal of the fluid. That is A battery system characterized by the following features.

10. The battery comprises at least two of the aforementioned battery modules, The two battery modules have characteristics defined by different pressure-temperature curves. The battery system according to feature 9.

11. The aforementioned curves have different slopes. The battery system according to feature 10.

12. The aforementioned curves show different pressure values ​​at the same temperature. The battery system according to claim 10 or 11.

13. Housing for each battery module Equipped with, The housing defines a convection path for controlling the temperature of the battery module. The battery system according to any one of 9 to 12, characterized by the features described herein.

14. The aforementioned enclosures are connected in series to form a continuous convection path. The battery system according to feature 13.

15. The housing is provided with at least one valve between the two halves. The battery system according to feature 14.

16. The aforementioned enclosures are arranged in parallel. The battery system according to feature 15.

17. Each housing has a valve on the downstream side of the convection path. The battery system according to any one of claims 13 to 16.

18. The housing has a fan on the upstream side of at least one of the convection paths. The battery system according to any one of claims 13 to 17.

19. A method for controlling the operating pressure and / or temperature of at least one battery module, A step of housing a plurality of battery cells within an internal cavity of at least one battery module, wherein the internal cavity is airtightly sealed and the plurality of battery cells are immersed in a fluid, A step of monitoring the temperature and / or pressure of the module, When using the battery module, the process includes maintaining a constant mass of the fluid within the battery module and hermetically isolating the battery module from the addition and removal of the fluid, while cooling or heating the module when the temperature and / or pressure of the module are outside a predetermined range. A method characterized by comprising:

20. The step of cooling or heating the module is performed by activating the Peltier effect module by controlling the direction of the current. The method according to feature 19.

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