Electric battery module containing battery cells divided into groups, with cyclic distribution of a temperature-regulating liquid to the different cell groups of the module

Abstract

An electric battery pack comprises one or more battery modules. Inside the container (4) of at least one module (1), the battery cells (2) are arranged in groups (I, II) configured and arranged to be traversed in parallel by a flow of a temperature-regulating liquid. The spaces between the cells (2) of the different groups (I, II) of cells communicate, on their inlet side, with respective inlet sub-collectors (51, 52). The inlet sub-collectors (51, 52) are hydraulically isolated from one another and are all in communication, independently and in parallel with each other, with an inlet collector chamber (5) of the module (1). Between the inlet collector chamber (5) and the inlet sub-collectors (51, 52) of the module (1) is interposed a distribution system (D) to which a respective control device (E) is associated. The control device (E) is configured such that, in operation, the distribution system (D) enables a greater flow of the temperature-regulating liquid, equal to most or all of the flow entering the module (1), cyclically only to one, or only to some, of the groups (I, II) of battery cells (2), while the other groups (I, II) of cells receive a reduced or null flow of the temperature-regulating liquid, such that, at the end of each cycle, a plurality of groups (I, II) of battery cells (2) have received in turn, for a determined time interval, the greater flow of temperature-regulating liquid.

Description

[0001] Electric battery module containing battery cells divided into groups, with cyclic distribution of a temperature-regulating liquid to the different cell groups of the module"

[0002] ****

[0003] DESCRIPTION TEXT

[0004] Field of the invention

[0005] The present invention relates to an electric battery pack, of the type comprising one or more electric battery modules, wherein each module comprises:

[0006] - a module container,

[0007] - a plurality of battery cells arranged within the module container, - wherein the battery cells are spaced apart from each other, so as to define spaces between the cells,

[0008] - wherein the battery cells are configured and arranged to come into direct contact with a flow of a temperature-regulating liquid that passes through the module container, for maintaining the battery cells within a determined temperature field,

[0009] - wherein the module container is configured such that the temperature-regulating liquid flows from an inlet collector chamber, which extends below the battery cells, through the spaces between the battery cells and up to an outlet collector chamber which extends above the battery cells.

[0010] Background of the invention

[0011] Electric battery packs including modules having the characteristics indicated above are known and have been used for some time.

[0012] Figures 1-4 of the attached drawings refer to a single battery module of a known type, including a single group of cells. A battery pack may generally comprise a plurality of such battery modules, each provided with its respective container and arranged within a common external container.

[0013] Figure 1 is a schematic perspective view of a module 1 forming part of a battery pack. The module 1 includes a plurality of prismatic cells 2, arranged aligned along a direction X inside a container 4.

[0014] Figure 2 is an enlarged scale perspective view of a prismatic battery cell 2, comprising a container having a top surface 2A, two opposite main surfaces 2B, which inside the container 4 are arranged orthogonally to the direction X of cell alignment, two side walls 2C and a bottom wall 2D. In the example illustrated in figure 2, the positive pole 3P and the negative pole 3N of the battery cell 2 protrude from the top wall 2A. However, it is also possible for the two poles 3P, 3N, to be disposed on one of the side faces 2C of the cell 2. According to a known technique per se, all the positive poles 3P and all the negative poles 3N of the cells 2 are electrically connected to each other and to two respective poles P and N protruding, in the illustrated example, from an end wall of the container 4 (see figure 1).

[0015] The battery cells 2 inside the container 4 of the module 1 are immersed in a flow of a temperature-regulating liquid (typically a dielectric oil) that passes through the internal space of the container 4.

[0016] Figure 3 is a schematic sectional view in the median vertical plane of the battery module of figure 1. With reference to this figure, the container 4 includes an inlet opening 5A for the temperature-regulating liquid, communicating with an inlet collector chamber 5 disposed below the battery cells 2. The container 4 further comprises an outlet opening 6A for the temperature-regulating liquid, communicating with an outlet collector chamber 6, disposed above the array of battery cells 2. Again with reference to figure 3, the battery cells 2 are arranged spaced apart from each other so as to define a plurality of spaces 7 between the cells 2, which place the inlet collector chamber 5 in hydraulic communication with the outlet collector chamber 6. In general, this is achieved by interposing spacer frames between the cells. The assembly of cells and spacer frames is maintained in an assembled condition by applying a compression force along the longitudinal direction X (figure 1 ) by means of any known type of means, for example by means of tie rods (not shown). The size of the spaces 7 interposed between the cells 2 has been exaggerated for clarity in figure 3. In reality, the distance between two adjacent cells may be, for example, on the order of a few millimeters (e.g., about 2 mm).

[0017] Figure 4 is a partially sectioned perspective view of a battery module of the known type described above, in which one of the cells 2 has been removed to illustrate a portion of a spacer frame, comprising a lower horizontal element 8, which extends along the bottom edge of a cell 2, for the entire width of the cell 2 (i.e., in the direction Y of figure 1).

[0018] Each element 8 has multiple passages 9 that place the inlet collector chamber 5 in communication with the respective space 7 between two cells 2. The passages 9 are relatively narrow, so as to offer a sufficiently high resistance to the flow of the temperature-regulating liquid to prevent the temperature-regulating liquid from tending to flow more in the spaces between the cells that are closer to the inlet 5A (figure 3) and / or the outlet 6A. In this way, in the aforementioned known solutions, an attempt is made to uniform the flow of the temperature-regulating liquid between the different spaces between the cells and, in each space between the cells, over the entire area of each cell.

[0019] In the present description, and in the attached drawings, the construction details relating to the temperature-regulating liquid supply circuit and the control of the temperature-regulating liquid temperature are not illustrated, since they can be implemented in any known way and also because such details, taken by themselves, do not fall within the scope of the present invention. In general, the temperature-regulating liquid supply system may include a pump to activate the liquid circulation and one or more heat exchangers to maintain the temperature-regulating liquid at a desired temperature. The temperature-regulating liquid (e.g., a dielectric oil) can perform both a cooling function, when the temperature of the battery module tends to exceed a predetermined maximum threshold value, and a heating function, when the temperature of the battery module tends to fall below a predetermined minimum threshold value. The temperature-regulating liquid supply system is preferably electronically controlled based on signals emitted by one or more sensors disposed in the battery module. Again, all the aforementioned details are not illustrated here, both because they can be implemented in any known way, and because they do not fall, taken by themselves, within the scope of the invention, and also because their elimination from the drawings makes the latter simpler and easier to understand.

[0020] Technical problem

[0021] The Applicant has already proposed various solutions in the field of temperature regulation systems for electric battery packs. See for example the Italian patent applications 102023000022692, 102023000022698, 102023000022704, 102023000025884, 102024000002776, 102024000002779, 102024000004423, 102024000007807, 102024000007813, 102024000007816, 102024000007828, 102024000013039, 102024000013492, 102024000014308, 102024000014314, 102024000014326, 102024000015637, 102024000016354, 102024000016933, 102024000020863, 102024000020875, 102024000021069, 102024000021546, 102024000022857, all still not available to the public at the date of the present invention.

[0022] Studies and experiences of the Applicant have shown that in solutions of the type indicated above it is extremely difficult to guarantee a homogeneous distribution of the flow in the spaces between the cells, also due to variations in the viscosity of the oil constituting the temperature-regulating liquid as the temperature varies.

[0023] Another problem is due to the relatively limited flow rate of the pump that supplies the temperature-regulating liquid to the battery pack. Due to the low flow rate provided by the pump (which is distributed among the different modules and among the different spaces between the cells of each module) and due to the small size (less than 3 millimeters) of each space between the cells (necessary to achieve a high volumetric energy density of the battery pack), the flow of the temperature-regulating liquid in the spaces between the cells is substantially laminar, which does not favor heat exchange (the heat transfer coefficient HTC is instead higher in the case of high-speed turbulent flow).

[0024] This problem is even more pronounced in the case the battery module has a relatively complex geometry, for example with complex internal passages within the module. In this case, a relatively high risk of leakage of the oil constituting the temperature-regulating liquid may result, due for example to the aging of the module, which causes a swelling ("swelling") of the cells), or also in general during a heating phase of the battery pack, for example after activation at temperatures lower than -10° C: in this case the problem of the oil pump is not one of a reduced flow rate, but of an excess of work required to push the oil under conditions of high viscosity. Another problem occurs during a fast charge of the battery pack, when, typically, due to the high charging power and the consequent power dissipated by the Joule effect, the cells heat up to a maximum allowable temperature Tmax before the charge is completed. In this condition, the power delivered to the battery is strongly reduced, waiting for the temperature, also due to the effect of the temperature regulation system, to fall below another predetermined threshold Tmin lower than Tmax. Once the acceptable Tmin is reached, the power delivered by the external charging system is raised again.

[0025] The aforementioned phenomenon is illustrated in the diagram of figure 5. In this diagram, the line C shows the state of charge of a battery cell, measured in ampere-hours (Ah) during a charging phase of the battery pack. As can be seen, the state of charge increases constantly, but with different slopes of the curve. From 0 to about 700 seconds it can be noted how the curve C has a steep slope, which effectively corresponds to a fast charge. After 700 seconds the curve C begins to have an asymptotic profile which corresponds to a decrease in the charging speed

[0026] The lines K1 , K2, K3, K4 show the temperature variation during the recharging of the battery pack in different areas of a face of a cell (respectively on one side, at the center, on the opposite side and in the lower part of the cell face). The curves K1, K2, K3 are substantially coincident, while the curve K4 is similar to the others, but shifted towards lower temperatures, as it relates to the lower part of the cell, which is better cooled by the temperature-regulating liquid coming from below.

[0027] The line A shows the variation of the electric current supplied during recharging. As can be observed, as soon as the battery cell reaches in some of its points (lines K1, K2, K3) a temperature around 50° C, the supply electric current is drastically reduced. This means that in practice the fast charging process actually lasts less than 700 seconds, after which it is no longer possible to charge with a high current.

[0028] There is therefore a need for further improvements in this field.

[0029] Further solutions in this field are known from documents US 2023 / 268578 A1 , US 2023 / 318118 A1 and US 2017 / 279172 A1.

[0030] Obiect of the invention The object of the present invention is to solve the aforementioned technical problems.

[0031] In particular, the invention has the objective of realizing an electric battery pack of the type indicated at the beginning of the present description, in which the temperature of the cells inside a battery module is maintained within a determined field under any operating condition, thanks to a high efficiency of the heat exchange with the temperature-regulating liquid.

[0032] Even more particularly, an object of the invention is to ensure that all the battery cells of a battery module receive, even if only periodically, a substantial flow rate of temperature-regulating liquid, capable of guaranteeing the cooling of the cells, without the need to use a high-power pump.

[0033] A further object of the invention is to make the battery charging phase faster, without involving a risk of thermal runaway of the battery cells.

[0034] Yet a further object is to also make faster a warm-up phase of the battery pack after activation at a very low ambient temperature

[0035] Summarv of the invention

[0036] With a view to achieving one or more of the aforementioned objects, the invention has for its subject an electric battery pack having the characteristics indicated at the beginning of the present description and characterized in that:

[0037] - inside the container of at least one module of the battery pack, the battery cells are arranged so as to form a plurality of groups of battery cells configured and arranged to be traversed in parallel by the flow of the temperature-regulating liquid,

[0038] - the spaces between the battery cells of each group of battery cells of said module communicate, on their inlet side, for the inlet of the flow of the temperature-regulating liquid, with a respective inlet sub-collector, - said inlet sub-collectors of said module are hydraulically isolated from one another and are all in communication, independently and in parallel with each other, with said inlet collector chamber of the module, which is disposed upstream of the inlet sub-collectors of the module,

[0039] - between the inlet collector chamber and said inlet sub-collectors of said module is interposed a distribution system to which a respective control device is associated,

[0040] - the control device of said distribution system is configured such that, in operation, the distribution system enables a greater flow of the temperature-regulating liquid, equal to most or all of the flow entering the module, cyclically only to one, or only to some, of the groups of battery cells, while the other groups of cells receive a reduced or null flow of the temperature-regulating liquid, such that, at the end of each cycle, a plurality of groups of battery cells have received in turn, for a determined time interval, said greater flow of temperature-regulating liquid.

[0041] In this way, each of said groups of cells inside the battery module receives in turn a greater flow of temperature-regulating liquid, which creates in the spaces between the cells of each block a high-speed flow, which guarantees a high efficiency of the heat exchange with the cells.

[0042] The present invention therefore stems from the observation that the solution to the problems discussed above, instead of being sought by dividing the flow of temperature-regulating liquid as uniformly as possible among the different groups of cells of the same battery module, can be found by concentrating all the flow, or most of the flow, in a single group at a time, and cyclically varying the group that receives most of the flow.

[0043] As is evident, the invention is applicable to any type of battery cells (prismatic, pouch or cylindrical).

[0044] In an example, the distribution system provided in the module comprises a plurality of control valves respectively associated with different groups of battery cells. The control valves can be electrically actuated valves, of the on / off type or of the proportional type, and said control device can comprise an electronic controller configured to actuate the control valves by cyclically opening only one of the control valves and leaving the other valves closed or only partially open.

[0045] In a variant, the distribution system comprises a distributor including a sliding or rotating movable member and an actuator of the movable member, under electronic control. For example, the control valves can have respective rotating shutters actuated by an electronically controlled electric motor.

[0046] According to a further preferred characteristic, the electronic controller for controlling the distribution system is configured to: - during a warm-up phase, after a cold activation of a module of the battery pack, in which the flow of temperature-regulating liquid is used to heat the module, supply most, or all, of the flow of temperature-regulating liquid only to one or more groups of battery cells of a part of the module, so as to make the heating of this part of the module faster,

[0047] - during a charging phase of the battery pack, in which the flow of temperature-regulating liquid is used to cool a module, enable the supply of an electric charging current only to one or more groups of battery cells of the module that in turn receive the greatest flow rate of the temperatureregulating liquid flow.

[0048] According to yet a further characteristic, the electronic controller for controlling the distribution system is configured to:

[0049] - receive data relating to the temperature of the cells of a module from sensors associated with the battery cells of the module,

[0050] - in the case the temperature of one or more battery cells of one or more groups of battery cells, detected by said sensors, exceeds a determined threshold, control said distribution system to supply most of the flow of temperature-regulating liquid to said one or more groups of battery cells that have exceeded the threshold temperature.

[0051] In a preferred embodiment, each inlet sub-collector of the module communicates with the spaces between the battery cells of the respective group of cells via relatively restricted passages defined in spacer members interposed between the battery cells, said passages being configured so as to offer a resistance to the flow of the temperature-regulating liquid sufficient to prevent a tendency of the temperature-regulating liquid to flow more in some spaces between the battery cells than in others. In a variant, the spacer members interposed between the battery cells of each group of battery cells of said module define a second series of relatively restricted passages for the temperature-regulating liquid, disposed downstream, with reference to the flow direction, relative to said restricted passages that place each inlet sub-collector in communication with the spaces between the battery cells of the respective group of battery cells, so as to promote a turbulent flow of the temperature-regulating liquid in the spaces between the cells and improve the heat exchange with the cells.

[0052] The invention also has for its subject the method of thermal control of a battery pack of the type described above.

[0053] Brief description of the figures

[0054] Further characteristics and advantages of the invention will result from the following description with reference to the attached drawings, provided purely by way of non-limiting example, in which:

[0055] figure 1 is a perspective view of a battery module according to the prior art,

[0056] figure 2 is a perspective view of a prismatic battery cell,

[0057] figure 3 is a schematic sectional view of the battery module of figure 1,

[0058] figure 4 is a schematic perspective view of an array of battery cells in a battery module according to the prior art,

[0059] figure 5 is a diagram illustrating the temperature variation of the battery cells during a charging phase, in the case of the previously proposed systems,

[0060] figure 6 illustrates a distribution scheme of the temperatureregulating liquid in a module of a battery pack according to the invention, figures 7, 8 are diagrams illustrating how the flow of the temperatureregulating liquid is distributed among different groups of cells of the battery pack,

[0061] figure 9 illustrates a variant of figure 6, and

[0062] figure 10 illustrates the flow of the temperature-regulating liquid in the space between two cells of a further embodiment of the battery pack according to the invention.

[0063] Detailed description of the invention

[0064] Figures 1-5 have already been described above.

[0065] In figures 6-10, parts common with those illustrated in figures 1-4 are indicated by the same references.

[0066] The battery pack according to the invention comprises one or more modules of the type described above with reference to figures 1-4, i.e., wherein the module comprises a container 4 inside which the battery cells 2 are arranged and wherein the cells 2 are immersed in a flow of a temperature-regulating liquid, for example a dielectric oil. Also in the case of the invention, inside the container 4 of the module 1 are disposed an inlet collector chamber 5 disposed below the cells and an outlet collector chamber 6 disposed above the cells, the two chambers 5, 6 communicating with each other via the spaces between the cells 2.

[0067] With reference to figure 6, which is a schematic illustration of the internal configuration of a single module 1 of the battery pack, a first important characteristic of the present invention resides in the fact that inside the module container, the battery cells 2 are arranged so as to form a plurality of groups I, II, etc. of battery cells 2 (figure 6 illustrates only two groups for simplicity) configured and arranged to be traversed in parallel by the flow of the temperature-regulating liquid. The spaces between the battery cells 2 of each group I, II of battery cells of the module 1 communicate, on their inlet side for the flow of the temperature-regulating liquid, with a respective inlet sub-collector 51, 52, etc. The inlet subcollectors 51 , 52 internal to the module 1 are hydraulically isolated from one another and are all in communication, independently and in parallel with each other, with the inlet collector chamber 5 of the module, which is disposed upstream of the inlet sub-collectors 51, 52 of the module (with reference to the flow of the temperature-regulating liquid).

[0068] According to a further essential characteristic of the invention, between the inlet collector chamber 5 and said inlet sub-collectors 51 , 52 of the module 1 is interposed a distribution system D (illustrated only schematically in the drawings) of any known type, to which a respective control device is associated, which in the example of figure 6 is an electronic controller E,

[0069] According to the invention, the control device E of the distribution system D is configured such that, in operation, the distribution system D enables a greater flow of the temperature-regulating liquid, equal to most or all of the flow entering the module 1 , cyclically only to one, or only to some, of the groups I, II, etc. of battery cells 2, while the other groups of cells receive a reduced or null flow of the temperature-regulating liquid, such that, at the end of each cycle, a plurality of groups of battery cells 2 have received in turn, for a determined time interval, said greater flow of temperatureregulating liquid.

[0070] The present invention therefore stems from the observation that the solution to the problems discussed above, instead of being sought by dividing the flow of temperature-regulating liquid as uniformly as possible among the different cells of the same module, can be found by concentrating all the flow, or most of the flow, in a single group of cells at a time, and cyclically varying the group that receives most of the flow. In this way, for a given maximum flow rate of the temperature-regulating liquid supply pump, the group of cells that in turn receives all the flow rate, or almost all the flow rate, supplied by the pump is subject to a much more effective thermal control action compared to what occurs in the previously proposed solutions.

[0071] By selectively and cyclically supplying the different groups of cells with the maximum pump flow rate, the invention allows generating a turbulent flow regime instead of a laminar one. It is demonstrated that a turbulent regime can increase the heat transfer coefficient (HTC) up to five times compared to a laminar regime.

[0072] In the example of figure 6, the distribution system D comprises a plurality of control valves V respectively associated with different groups I, II, etc. of battery cells. In particular, the control valves V are electrically actuated valves, of the on / off type or of the proportional type, and the control device comprises an electronic controller E configured to actuate the control valves V by cyclically opening only one of the control valves and leaving the other valves closed or only partially open.

[0073] In another example, the distribution system D of the module 1 comprises a distributor D of any known type including a sliding or rotating movable member and an actuator of the movable member, under electronic control.

[0074] Each sub-collector 51, 52, etc. communicates with the spaces between the cells of the respective group of cells preferably via the restricted passages 9, configured, as already illustrated above, so as to offer a resistance to the flow of the temperature-regulating liquid sufficient to prevent a tendency of the temperature-regulating liquid to flow more in some spaces between the battery cells than in others. In this way, a uniform distribution of the temperature-regulating liquid over the entire area of each cell 2 is obtained, and furthermore, the creation of a turbulent regime downstream of each restricted passage is promoted. According to a further preferred characteristic of the invention, the electronic controller E for controlling the distribution system D can be configured such that, during a warm-up phase, after an activation of the module of the battery pack at a low temperature, in which the flow of temperature-regulating liquid is used to heat the module, most, or all, of the flow of temperature-regulating liquid is supplied only to one or more groups of battery cells of a part of the module, so as to make the heating of this part of the module faster (deferring the heating of the remaining part of the module to a subsequent phase).

[0075] Furthermore, the electronic controller E for controlling the distribution system D can be configured such that, during a charging phase of the battery pack, in which the flow of temperature-regulating liquid is used to cool the module, the electric charging current is supplied only to one or more groups of battery cells of the module that in turn receive the greatest flow rate of the temperature-regulating liquid flow.

[0076] Figure 6 does not show the circuit for the circulation of the temperature-regulating liquid outside the module container and outside the battery pack, which comprises an electric pump, preferably of the adjustable type, to activate the circulation of the temperature-regulating liquid, and one or more heat exchangers to re-establish a desired temperature of the temperature-regulating liquid coming from the outlet of the battery pack, before it is reintroduced into the battery pack.

[0077] The operating principle of the temperature-regulating liquid distribution system according to the present invention is illustrated in the diagrams of figures 7 and 8. With reference to figure 7 (which refers to an example with four groups of cells I, II, III and IV) the maximum fluid flow rate is supplied cyclically only to one of the groups, for a determined time interval. Figure 7 shows the four phases in which the four groups in turn receive a maximum flow rate, while the other groups receive a null or very reduced flow rate. Figure 8 shows that in turn three groups receive a reduced flow rate.

[0078] During a recharge of the module, the time necessary for the recharge can be subdivided such that all the groups of the module are supplied equally and cyclically, guaranteeing a greater removal of heat from the system. For example, if the recharge period is 24 minutes and there are 8 groups of cells, two groups can be recharged at a time. The flow rate will be four times higher compared to the case of constant supply. The duration of the supply cycle can be set to 2 minutes for each group, repeating this sequence three times. This approach guarantees that all groups benefit equally from the improved turbulent flow conditions, optimizing heat removal during the recharge process.

[0079] Figure 9 shows a variant in which the control valves V are mechanically actuated valves, and the control device includes a mechanical transmission R interposed between an electric actuation motor M and the control valves V. For example, the control valves V can be rotating shutters constituted by different portions of a tubular element R commanded in rotation by the electric motor M. In the various positions of the rotating member R the latter enables the passage of liquid only to one of the groups of cells. The advantages of this system include the presence of a single control component, the electric motor, whose rotation speed determines the frequency of the cooling passage between the different blocks of cells. This design eliminates the need for multiple solenoid valves, simplifying the system, reducing costs and improving reliability by minimizing the number of control components.

[0080] In a further embodiment, in each space between the cells (see figure 10) in addition to the element 8 with the restricted passages 9, a spacer member 10 is disposed which defines a second series of relatively restricted passages 11 for the temperature-regulating liquid, disposed downstream, with reference to the flow direction, relative to the restricted passages 9 that place the collector chamber of each block of cells in communication with the spaces between the cells of the block, so as to further promote a turbulent flow of the temperature-regulating liquid in the spaces between the cells and improve the heat exchange with the cells.

[0081] As is evident from the preceding description, the invention allows achieving a plurality of advantages, including in particular the following.

[0082] 1) Greater heat transfer efficiency: the selective and cyclic supply of all, or almost all, the flow rate supplied by the pump to the different groups of cells of the module generates a turbulent flow regime, significantly improving the heat transfer coefficient (HTC) up to five times compared to a laminar flow regime, which translates into better thermal management of the battery pack.

[0083] 2) Even in the case it is not possible to generate a turbulent type flow, for example due to low temperatures that increase the viscosity of the oil and therefore prevent vortex motions, or worse in the case that cell swelling phenomena have drastically altered the passages between cells by shrinking them, it is guaranteed that each group of cells will receive, albeit periodically, a predetermined flow rate of fluid, avoiding dangerous overheating zones.

[0084] 3) An optimized cooling and charging strategy can be implemented: by combining cooling and charging cycles, the invention allows charging at maximum power only the groups of cells that are currently being cooled with the maximum flow. This reduces the risk of overheating while maximizing the efficiency of the charging process.

[0085] 4) Furthermore, it is possible to heat only one or more groups of cells during the warm-up phase of the vehicle, thereby reducing the time before the vehicle itself can be put into driving condition.

[0086] 5) Energy efficiency: the cyclic supply approach guarantees that the pump operates at its point of maximum efficiency, reducing energy consumption and wear compared to a stationary operation where all groups of cells are continuously supplied at a lower flow rate.

[0087] 6) Increased battery longevity: by maintaining optimal thermal conditions and avoiding overheating, the invention can help prolong the life of the battery cells, which is crucial for electric vehicles and stationary energy storage systems.

[0088] 7) Modular and scalable design: the invention is adaptable to different battery module configurations, allowing easy scaling depending on the application and desired performance.

[0089] 8) Reduced charging time: the possibility of charging groups of cells at maximum power while they are optimally cooled can lead to a reduction in the overall charging time without compromising safety or battery health.

[0090] 9) Flexibility in system design: the cyclic approach to supply and charging offers flexibility in the design of the thermal management system, allowing different flow rates, cycle times and cooling strategies to be adapted to specific applications.

[0091] Naturally, the principle of the invention remaining the same, the construction details and the embodiments may vary widely with respect to what has been described and illustrated purely by way of example, without thereby departing from the scope of the present invention, as defined in the attached claims.

Claims

CLAIMS1. Electric battery pack, comprising one or more modules (1) of electric battery, wherein each module (1) comprises:- a container (4) of the module (1 ),- a plurality of battery cells (2) arranged within the container (4) of the module (1),- wherein the battery cells (2) are spaced apart from each other, so as to define spaces between the cells (2),- wherein the battery cells (2) are configured and arranged to come into direct contact with a flow of a temperature-regulating liquid that passes through the container (4) of the module (1), for maintaining the battery cells (2) within a determined temperature field,- wherein the container (4) of the module (1 ) is configured such that the temperature-regulating liquid flows from an inlet collector chamber (5), which extends, in the condition of use of the battery pack, below the battery cells (2), through the spaces between the battery cells (2) and up to an outlet collector chamber (6) which extends above the battery cells (2),said battery pack being characterized in that:- inside the container (4) of at least one module (1) of the battery pack, the battery cells (2) are arranged so as to form a plurality of groups (I, II) of battery cells (2) configured and arranged to be traversed in parallel by the flow of the temperature-regulating liquid,- the spaces between the battery cells (2) of each group (I, II) of battery cells of said module (1 ) communicate, on their inlet side for the inlet of the flow of the temperature-regulating liquid, with a respective inlet subcollector (51, 52),- said inlet sub-collectors (51 , 52) of said module (1 ) are hydraulically isolated from one another and are all in communication, independently and in parallel with each other, with said inlet collector chamber (5) of the module (1), which is disposed upstream of the inlet sub-collectors (51, 52) of the module (1),- between the inlet collector chamber (5) and said inlet sub-collectors (51, 52) of said module (1) is interposed a distribution system (D) to which a respective control device (E) is associated,- the control device (E) of said distribution system (D) is configured such that, in operation, the distribution system (D) enables a relatively greater flow of the temperature-regulating liquid, equal to most or all of the flow entering the module (1), cyclically only to one, or only to some, of the groups (I, II) of battery cells (2), while the other groups (I, II) of cells receive a reduced or null flow of the temperature-regulating liquid, such that, at the end of each cycle, a plurality of groups (I, II) of battery cells (2) have received in turn, for a determined time interval, said greater flow of temperature-regulating liquid.

2. Battery pack according to claim 1 , wherein the distribution system (D) of said module (1) comprises a plurality of control valves (V) respectively associated with different groups (I, II) of battery cells.

3. Battery pack according to claim 1 , wherein the distribution system (D) of said module (1) comprises a distributor (D) including a sliding or rotating movable member and an actuator of said movable member, under electronic control.

4. Battery pack according to claim 2, wherein the control valves (V) are electrically actuated valves, of the on / off type or of the proportional type, and said control device comprises an electronic controller (E) configured to actuate the control valves (V) by cyclically opening only one of the control valves and leaving the other valves closed or only partially open.

5. Battery pack according to claim 1, characterized in that it comprises an electronic controller (E) for controlling said distribution system (D), and in that said electronic controller (E) is configured to:- during a warm-up phase, after a cold activation of a module of the battery pack, in which the flow of temperature-regulating liquid is used to heat the module (1), supply most, or all, of the flow of temperatureregulating liquid only to one or more groups (I, II) of battery cells of a part of the module, so as to make the heating of this part of the module (1 ) relatively faster,- during a charging phase of the battery pack, in which the flow of temperature-regulating liquid is used to cool a module, enable the supply of an electric charging current only to one or more groups (I, II) of battery cells of the module (1) that in turn receive the greatest flow rate of the flow of temperature-regulating liquid.

6. Battery pack according to claim 1, characterized in that it comprises an electronic controller (E) for controlling said distribution system (D), and in that said electronic controller (E) is configured to:- receive data relating to the temperature of the cells (2) of a module from sensors associated with the battery cells (2) of the module,- in the case the temperature of one or more battery cells (2) of one or more groups (I, II) of battery cells (2), detected by said sensors, exceeds a determined threshold, control said distribution system (D) to supply most of the flow of temperature-regulating liquid to said one or more groups (I, II) of battery cells (2) that have exceeded the threshold temperature.

7. Battery pack according to claim 1 , wherein each inlet sub-collector (51, 52) of said module (1) communicates with the spaces between the battery cells (2) of the respective group (I, II) of cells via relatively restricted passages (9) defined in spacer members (8) interposed between the battery cells (2), said passages being configured so as to offer a resistance to the flow of the temperature-regulating liquid sufficient to prevent a tendency of the temperature-regulating liquid to flow more in some spaces between the battery cells (2) than in others.

8. Battery pack according to claim 7, wherein the spacer members (8, 10) interposed between the battery cells (2) of each group (I, II) of battery cells (2) of said module (1) define a second series of relatively restricted passages for the temperature-regulating liquid, disposed downstream, with reference to the flow direction, relative to said restricted passages that place each inlet sub-collector (50, 51) in communication with the spaces between the battery cells (2) of the respective group (I, II) of battery cells, so as to promote a turbulent flow of the temperature-regulating liquid in the spaces between the cells and consequently improve the heat exchange with the cells.

9. Method for the thermal control of an electric battery pack, wherein the battery pack comprises one or more electric battery modules (1), wherein each module (1) comprises:- a container (4) of the module (1 ),- a plurality of battery cells (2) arranged within the container (4) of the module (1),- wherein the battery cells (2) are spaced apart from each other, soas to define spaces between the cells (2),- wherein the battery cells (2) are configured and arranged to come into direct contact with a flow of a temperature-regulating liquid that passes through the container (4) of the module (1), for maintaining the battery cells (2) within a determined temperature field,- wherein the container (4) of the module (1 ) is configured such that the temperature-regulating liquid flows from an inlet collector chamber (5), which extends below the battery cells (2), through the spaces between the battery cells (2) and up to an outlet collector chamber (6) which extends above the battery cells (2),said method being characterized in that:- inside the container (4) of one or more modules (1 ), the battery cells (2) are arranged so as to form a plurality of groups (I, II) of battery cells (2) configured and arranged to be traversed in parallel by the flow of the temperature-regulating liquid,- the spaces between the battery cells (2) of each group (I, II) of battery cells of the module (1) communicate, on their inlet side for the flow of the temperature-regulating liquid, with a respective inlet sub-collector (51 , 52),- the inlet sub-collectors (51, 52) of the module (1) are hydraulically isolated from one another and are all in communication, independently and in parallel with each other, with said inlet collector chamber (5) of the module (1), which is disposed upstream of the inlet sub-collectors (51, 52) of the module (1),- between the inlet collector chamber (5) and said inlet sub-collectors (51, 52) of said module (1) is interposed a distribution system (D) to which a respective control device (E) is associated,- the distribution system (D) is controlled so as to enable a greater flow of the temperature-regulating liquid, equal to most or all of the flow entering the module (1 ), cyclically only to one, or only to some, of the groups (I, II) of battery cells (2), while the other groups (I, II) of cells receive a reduced or null flow of the temperature-regulating liquid, such that, at the end of each cycle, a plurality of groups (I, II) of battery cells (2) have received in turn, for a determined time interval, said greater flow of temperature-regulating liquid.

10. Method according to claim 9, characterized in that it comprises the operations of:- during a warm-up phase, after a cold activation of a module (1 ) of the battery pack, in which the flow of temperature-regulating liquid is used to heat the module (1 ), supply most, or all, of the flow of temperatureregulating liquid only to one or more groups (I, II) of battery cells (2) of a part of the module (1), so as to make the heating of this part of the module (1) faster,- during a charging phase of the battery pack, in which the flow of temperature-regulating liquid is used to cool a module (1), enable the supply of an electric charging current only to one or more groups (I, II) of battery cells of the module (1 ) that in turn receive the greatest flow rate of the flow of temperature-regulating liquid,- during the operation of the battery pack, receive data relating to the temperature of the battery cells (2) of a module (1) from sensors associated with the battery cells (2) of the module, and, in the case the temperature of one or more battery cells (2) of one or more groups (I, II) of battery cells (2), detected by said sensors, exceeds a determined threshold temperature, control said distribution system (D) to supply most of the flow of temperature-regulating liquid to said one or more groups (I, II) of battery cells (2) that have exceeded the threshold temperature.

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