Roll battery cell comprising cell electrodes and held in a cell casing

Abstract

A battery cell (100) comprises a casing (105) and a roller (102) housed within the casing (105). The roller (102) defines a central volume (106) around which the roller (102) is wound. The roller (102) includes electrodes (103, 104) of the cell (100). The cell (100) includes at least one return element (101) arranged at least partially within the central volume (106). This return element (101) exerts a return force on the roller (102) to maintain the roller (102) between the return element (101) and a wall (107) of the casing (105) of the cell (100). Figure to be published with the abbreviation: Fig. 3

Description

Title of the invention: Roller battery cell comprising cell electrodes and held in a cell housing Technical field of the invention

[0001] The technical field of the invention relates to battery cells, in particular for a vehicle comprising an electric motor to be powered by a battery comprising cells according to the present invention.

[0002] More particularly, the present invention relates to a battery cell, said cell comprising a casing and a roller housed in the casing, the roller delimiting a central volume around which the roller is formed by winding, the roller comprising electrodes of the cell. Prior art

[0003] It is known from the prior art of roll-type battery cells comprising cell electrodes, also known as "jelly roll" in English.

[0004] Conventionally, the roll of a battery cell can be formed by winding a multilayer material comprising successively a first electrode sheet, a first separator sheet, a second electrode sheet, and a second separator sheet. This roll can be formed by winding the multilayer material onto a rotating winding mandrel. After the roll is formed, the winding mandrel is separated from the roll, leaving an empty central volume in the center of said roll. The roll is then inserted into a rigid casing, and the central volume is either left empty of solid material or a rigid body, therefore of fixed dimensions and, for example, tubular, is inserted inside the central volume. The cell also includes an electrolyte contained within the casing.

[0005] The manufacture of such a cell requires high industrial precision, in that the housing volume for the roller must be properly sized to allow the roller to be inserted into the housing and to limit its movement within the housing to prevent the roller from collapsing, particularly when its central volume is left empty of solid material. "Collapse" means that the multilayer material breaks down inside the housing, which can cause misalignment of the electrodes (in particular the first and second electrode sheets mentioned above) and the separator (in particular the first and / or second separator sheets mentioned above). In other words, the multilayer material unwinds from the inside, within the central volume. Although current cells, when properly sized and While the parameters are generally satisfactory, they can still be improved. Indeed, changes in the dimensions and / or parameters of the electrodes alter the charge / discharge behavior of the cells. Successive charge and discharge cycles of the cell cause movement of the roller within the casing. Naturally, the central volume can vary accordingly, sometimes causing the roller to collapse within this central volume. Roller collapse reduces cell performance. In the worst-case scenarios, roller collapse can lead to dramatic accidents, such as explosions or fires, particularly due to short circuits caused by direct contact between electrodes at opposite potentials (especially contact between the first and second electrode sheets) due to misalignment of the sheets (i.e.the first electrode sheet, the first separator sheet, the second electrode sheet and the second separator sheet) of the multilayer. .

[0006] Thus, there is a need to improve the cell to improve the retention of the roller in the casing, in particular with a view to limiting the occurrence of an accident such as mentioned above. Object of the invention

[0007] The present invention aims to improve the retention of the roller in the casing.

[0008] To this end, the invention relates to a battery cell, said cell comprising a casing and a roller housed in the casing, the roller delimiting a central volume around which said roller is formed by winding, the roller comprising electrodes of the cell, the cell comprising at least one return element arranged at least partly in the central volume, said at least one return element exerting a return force on the roller tending to ensure retention of the roller between said at least one return element and a wall of the casing of the cell.

[0009] This avoids the displacements / movements of the roller within the cell which could lead to a collapse of the roller as mentioned in the prior art section or to the creation of short circuit(s) within the cell.

[0010] The cell may further include one or more of the following characteristics.

[0011] According to a characteristic of the cell, the retention of the roller is ensured by compression of the roller between said at least one return element and the wall of the casing.

[0012] This compression makes it possible to obtain frictional forces adapted to maintaining the roller in the housing and makes it possible to tend to effectively avoid the collapse of the roller by taking into account the variation, over time, of the central volume and the natural movements of the roller.

[0013] According to a characteristic of the cell, said at least return element is configured so as to allow a variation of the volume occupied by the roller around the central volume.

[0014] This allows the expansions inside the cell to be absorbed while maintaining the roller's position in the casing.

[0015] According to a characteristic of the cell, the cell comprises a plurality of return organs distributed in the central volume along an axis of the roller.

[0016] This allows the benefit of the presence of the restoring force to be achieved while reducing the overall weight of the cell, since specific areas of the central volume can then be devoid of a restoring force. The reduction in the cell's weight leads to a reduction in the battery's weight, which in turn, where applicable, leads to a reduction in the fuel consumption of the vehicle incorporating the battery and powered by it.

[0017] According to a characteristic of the cell, the return elements are arranged so as to occupy at least 70% of the height of the roller within the central volume.

[0018] This ensures proper support of the roller while limiting the mass added to the cell to limit its weight.

[0019] According to a feature of the cell, said at least one return member is elongated and extends in the central volume from a first longitudinal end of the roller to a second longitudinal end of the roller, opposite the first longitudinal end of the roller, so as to exert its return force over its entire length.

[0020] This ensures a uniform distribution of the roller support, in particular over the height of the cell taken along the direction of the roller winding axis.

[0021] According to a characteristic of the cell, said at least one return element is a spring.

[0022] This has the advantage of being simple to implement while having a low unit cost.

[0023] According to a characteristic of the cell, the spring is a torsion spring in the form of an element wound on itself and configured so as to produce a radial force enabling the roller to be stressed towards the wall.

[0024] Such an embodiment of the spring is easy to implement and the wound element will tend to naturally open / unwind, which induces the radial force.

[0025] According to a characteristic of the cell, the spring is a helical spring.

[0026] The coils of such a spring advantageously make it possible to ensure the desired restoring force.

[0027] According to a characteristic of the cell, said at least one return element is made of steel.

[0028] The steel is suitable to perform the desired function while being compatible for use in the cell.

[0029] According to a characteristic of the cell, said at least one restoring organ is an elastic body or a foam.

[0030] These are two alternatives to a spring that can be adapted as a return element. The elastic body or foam have the advantage of being inexpensive and, where applicable, present less risk of short circuit because they can be electrically insulating.

[0031] According to a characteristic of the cell, the return force of said at least one return element is substantially radial to the winding axis of the roller and oriented towards the wall of the casing.

[0032] This prevents the roll from collapsing in the central volume.

[0033] According to a characteristic of the cell, the restoring force of said at least one restoring element is omnidirectional around the winding axis of the roller and directed towards the wall of the casing.

[0034] This improves support to prevent the roll from collapsing in the central volume.

[0035] The invention also relates to a method for manufacturing the battery cell, in particular as described above, the method comprising the following steps: a) providing the casing; b) provide the roll; c) insert the roller into the case; d) insert said at least one return device into the central volume.

[0036] This allows the cell to be manufactured in a simple way while ensuring adequate support for the roller.

[0037] The manufacturing process may further include one or more of the following features.

[0038] According to a feature of the manufacturing process, step d) is such that said at least one return member is inserted compressed.

[0039] Compressing said at least one return member allows it to be inserted into the central volume quickly without damaging the roller.

[0040] According to a feature of the manufacturing process, said at least one compressed return member has lateral dimensions, measured orthogonally to its direction of insertion in the central volume, strictly less than the lateral dimensions of the central volume measured orthogonally to the direction of insertion of said at least one compressed return member in the central volume.

[0041] This allows for a simple and secure insertion of said at least one return element into the central volume.

[0042] Other advantages and features may become apparent from the detailed description that follows. Brief description of the drawings

[0043] The invention will be better understood upon reading the following detailed description, given solely by way of non-limiting example and made with reference to the attached drawings listed below.

[0044] [Fig-1] Fig. 1 schematically represents a battery cell seen in perspective according to an embodiment of the invention.

[0045] [Fig.2] Fig.2 schematically represents one embodiment of the cell, for example of [Fig.1], according to a cross-sectional view taken orthogonally to the direction of measurement of the cell height.

[0046] [Fig.3] Fig.3 represents a particular embodiment of the cell, by example of [Fig.1], according to a cross-sectional view showing the presence of a recall organ located in the cell.

[0047] [Fig.4] Fig.4 represents a particular embodiment of the cell, by example of [Fig.1], according to a cross-sectional view, showing the presence of three recoil organs located in the cell.

[0048] [Fig. 5] [Fig. 5] schematically illustrates, in cross-section, a multilayer used to form a roll arranged in the cell.

[0049] [Fig.6] Fig.6 schematically illustrates, according to a cross-sectional view, a casing used to form the cell, particularly in the context of a cell manufacturing process.

[0050] [Fig.7] Fig.7 schematically illustrates, in cross-section, the casing in which the roll is arranged during the manufacturing process.

[0051] [Fig.8] Fig.8 schematically illustrates, in cross-section, the casing in which the roller and the return mechanism are arranged during the roller manufacturing process.

[0052] [Fig.9] Fig.9 schematically illustrates, according to a cross-sectional view, a particular realization of a step in the manufacturing process consisting of inserting the return element into the housing in which the roller is arranged.

[0053] [Fig. 10] Fig. 10 schematically illustrates, in cross-section, a particular embodiment of a step in the manufacturing process consisting of adding an electrolyte from the cell into the casing.

[0054] [Fig. 11] Fig. 11 schematically illustrates, according to a cross-sectional view, a particular embodiment of a step in the manufacturing process consisting of forming the roller to be inserted into the casing.

[0055] In these figures, the same reference numerals are used to designate the same elements. The elements shown in the different figures are not necessarily drawn to scale in order to facilitate understanding of the figures. Detailed description

[0056] The present invention relates to a battery cell 100 and proposes to integrate at least one return element 101 within the cell 100 in order to participate in maintaining a roll 102 of the cell 100, this roll 102 comprising electrodes 103, 104 of the cell 100. In particular, Figures 1 to 4 show such a cell 100 according to two embodiments respectively with one return element 101 ([Fig.3]) and with three return elements 101 ([Fig.4]), and [Fig.5] illustrates an example of a portion of a multilayer 111 intended to be wound to form the roll 102.

[0057] In particular, the cell 100 comprises a housing 105, and the roller 102 is housed within the housing 105. The roller 102 defines a central volume 106 around which said roller 102 is wound. Said at least one return element 101, which comprises the cell 100, is arranged at least partially within the central volume 106. Said at least one return element 101 exerts a return force on the roller 102, tending to ensure that the roller 102 is held between said at least one return element 101 and a wall 107 of the housing 105 of the cell 100.

[0058] By "central volume 106 around which said roller 102 is formed by winding", it is understood that the roller 102 is a winding, that is to say that it comprises an internal surface 102a delimiting the central volume 106 and an external surface 102b at the periphery of the roller 102 around a winding axis Al of the roller 102.

[0059] The wall 107 of the housing 105 is, preferably, a closed side wall at a first end, preferably longitudinal, by a bottom 108 of the housing 105, in particular from which the wall 107 of the housing 105 rises, and at a second end, preferably longitudinal, by a cover 109 of the cell 100 so as to delimit a sealed internal volume of the cell 100. Sealing is then ensured between the inside of the cell 100 (i.e. the internal volume) and the outside of the cell 100.

[0060] The cell 100 may include, in the housing 105, an electrolyte 110; this allows in particular the exchange of ions between the two electrodes 103, 104 to selectively charge or discharge the cell 100. In particular, the roller 102 is immersed in the electrolyte 110.

[0061] In particular, the electrolyte 110 fills the internal volume, in particular notwithstanding the presence of said at least one return element 101 and the roller 102.

[0062] Generally speaking, by "said at least one reminder organ 101", it is understood that the cell 100 may comprise one, or several, which may have identical or similar characteristics. Thus, in the present detailed description, everything that applies to at least one recall 101 organ applies to that recall 101 organ when it is unique or to each recall 101 organ when there are several.

[0063] The roller 102 can be of the right cylindrical type (whose cross-section takes the form of a circle) or of the prismatic type (whose cross-section takes the form of a polygon). In particular, in [Fig. 1] the roller 102 is a right cylinder.

[0064] For example, the roll 102 is formed by winding the multilayer 111 around itself, as illustrated for example in [Fig.5], comprising successively a first electrode sheet 112 (forming for example the aforementioned electrode 103), a first separator sheet 113, a second electrode sheet 114 (forming for example the aforementioned electrode 104) of opposite polarity to the first electrode sheet 112, and a second separator sheet 115.

[0065] Preferably, in cell 100, the electrolyte 110 impregnates the first and second sheets 113, 115 of separator.

[0066] The cell 100 with roller 102 is, in particular, called in the technical field of the invention “jelly roll”.

[0067] With respect to the winding axis Al shown in Figures 3 and 4, the roller 102 can form, radially with respect to the winding axis Al, a mille-feuille in which each layer corresponds to a part of the multilayer 111 mentioned above, said parts being in contact so as to tend towards the optimization of the energy density within the cell 100. In Figures 3 and 4, a spacing between the parts of the mille-feuille is schematically represented to schematize the presence of the electrolyte 110, but in reality there is contact between the layers in such a way that the first and second sheets 112, 113 of electrode are always separated by one of the first and second sheets 113, 115 of separator in order to avoid short circuits.

[0068] The 105 case is notably rigid.

[0069] According to an embodiment allowing: • to obtain frictional forces adapted to holding the roller 102 in the housing 105; and • to prevent the central volume 106, which may vary over time depending on the variation of the volume of the roller 102 and / or natural movements of the roller 102, from causing the roller to collapse; the retention of the roller 102 is preferably ensured by compression of the roller 102 between said at least one return element 101 and the wall 107 of the housing 105.

[0070] In fact, the rigidity of the housing 105 is such that it does not deform upon contact with the roller 102 and exerts a reaction force against the roller 102, particularly on its external surface 102b. This reaction force is opposed, where applicable locally, to the return effort of said at least one return member 101 from which it follows that the compression of the roller 102 is ensured by means of said at least one return member 101 which pushes the roller 102, in particular at its internal surface 102a, against the wall 107 of the housing 105.

[0071] For example, this compression is obtained by the restoring force of said at least one restoring member 101 which allows a stress on the roller 102 according to the arrows Fl of figures 3 and 4 in the direction of the housing 105, and more particularly in the direction of its wall 107. The arrows Fl are schematically represented in two per restoring member 101 in figures 3 and 4 and are oriented, for the section shown, in opposite directions towards facing portions of the wall 107.

[0072] For example, said at least one return element 101 is configured to allow a variation in the volume occupied by the roller 102 around the central volume 106. Thus, expansions of the roller 102 during the life of the cell 100 do not compromise the stability of the roller 102, thereby improving safety during the use of the cell 100. The central volume 106 can also vary according to the variation in the volume occupied by the roller 102.

[0073] Generally, the roller 102 can include a first longitudinal end 116 and a second longitudinal end 117 opposite the first longitudinal end 116 of the roller 102.

[0074] According to one embodiment, the cell 100 comprises a plurality of return elements 101 distributed within the central volume 106 along an axis of the roller 102. In particular, this axis of the roller 102 is in fact its longitudinal axis and may correspond to the winding axis Al. This embodiment is notably visible in [Fig. 4], which shows, by way of example, three return elements 101 distributed along the axis of the roller, which in the illustrated example coincides with the winding axis Al. Each return element 101 then contributes to pressing the roller 102 against its circumference, i.e., its external surface 102b facing the wall 107.

[0075] Preferably, the return elements 101 are arranged so as to occupy at least 70% of the height of the roller 102 within the central volume. The height of the roller 102 is measured along the roller axis mentioned above. Thus, the height of the roller 102 corresponds to the distance between the first longitudinal end 116 and a second longitudinal end 117.

[0076] In particular, each return member 101 is distant from each of the other return members 101, in other words the return members 101 do not cover the entire height of the roller 102.

[0077] According to one embodiment, such as illustrated for example in [Fig. 3], said at least one return element 101 is elongated and extends into the central volume 106 from the first longitudinal end 116 of the roller 102 to the second longitudinal end 117 of the roller 102 so as to exert its restoring force along its entire length, in particular radially in the direction of the wall 107. For example, said at least one restoring member 101 exerts its restoring force along its entire length in order to press the roller 102 at its circumference, i.e. its external surface 102b facing the wall 107, against the wall 107. In other words, the restoring force of said at least one restoring member 101 is exerted transversely, and preferably radially, to the longitudinal direction of the roller 102.

[0078] According to one embodiment, and in particular as illustrated in [Fig.3], the cell 100 comprises a single return organ 101.

[0079] On [Fig.3], said at least one return member 101 is arranged entirely in the central volume 106, but it can just as easily protrude from the roller 102 from its first and second longitudinal ends 116, 117 if the configuration of the cell 100 allows it.

[0080] On [Fig.3], by way of example, the first longitudinal end 116 of the roller 102 is proximal to, and in particular in contact with, the cover 109 and distal to the bottom 108; while the second longitudinal end 117 is distal to the cover 109 and proximal to, and in particular in contact with, the bottom 108.

[0081] Said at least one return element 101 may be a spring.

[0082] The spring may be a torsion spring, for example in the form of an element wound upon itself and configured to produce a radial force that drives the roller 102 towards the wall 107. The wound element can be a metal sheet or a metal strip. The tendency of the wound element to open or unwind will exert the restoring force corresponding to the aforementioned radial force.

[0083] The torsion spring can be a spiral torsion spring.

[0084] The spring, and therefore said at least one return member 101, may be a spring helical. In this case, the helical spring is advantageously arranged in the central volume 106 so that its direction of extension, around which its coils are formed, is substantially parallel to the winding axis Al of the roller 102. The helical spring, thus positioned in the central volume 106, is subjected to stresses in the direction that all or part of its coils are compressed transversely to its direction of extension, thereby ensuring the restoring force radially with respect to its direction of extension, thus maintaining the roller 102 between the helical spring and the wall 107 of the housing 105. In fact, the radial compression of the helical spring will tend to modify its length, and the properties of the helical spring will induce stresses within it, tending to return it to its free length, resulting in the generation of the restoring force. radial against the internal surface 102b of roller 102. The helical spring can be in compression.

[0085] By "substantially parallel to the winding axis Al of roller 102", it is understood to be parallel or parallel to plus or minus 10 degrees.

[0086] The helical spring can be a steel wire, in particular stainless steel. The steel wire is then shaped in a suitable manner to form the turns around the direction of extension of the helical spring.

[0087] Said at least one return organ 101 may be made of steel.

[0088] Said at least one recall organ 101 may be a foam.

[0089] Said at least one 101 return unit may be a plastic return element.

[0090] Said at least one return element 101 may be an elastic body. In this case the An elastic body can be an elastic material which has the property of tending to undergo expansion when it has undergone compression in order to exert the restoring force on roller 102.

[0091] Preferably, the return force of said at least one return member 101 is substantially radial to the winding axis Al of the roller 102 and oriented towards the wall 107 of the housing 105. For example, this orientation is shown schematically by the arrows Fl in figures 3 and 4. This is made possible in particular in the context of the embodiment where the spring is a torsion spring or a helical spring as described above.

[0092] By "substantially radial", it is understood to be perpendicular, or orthogonal, to the winding axis Al, or perpendicular, or orthogonal, to the winding axis Al of roller 102 at plus or minus 10 degrees.

[0093] The return force of said at least one return member 101 can be omnidirectional, in particular around the winding axis Al of the roller 102 and directed towards the wall 107 of the housing 105. For example, this makes it possible to ensure a preferably homogeneous pressing of the roller 102 on at least a portion of the surface, for example of revolution or adopting the form of a closed loop of polygonal section in particular orthogonal to the winding axis Al, of the wall 107.

[0094] The invention also relates to a method for manufacturing the battery cell 100. This method comprises the following steps: a) provide the 105 case, for example as shown in [Fig.6]; b) provide the roll 102 including the electrodes 103, 104 of the cell 100; c) insert roller 102 into case 105, [Fig.7] shows as an example the result of step c); d) insert said at least one reminder organ 101 into the central volume 106 (for example as shown in Figures 8 and 9). These steps have the advantage of being easy to implement and the addition of said at least one return element 101 ultimately allows for the proper retention of the roller 102 in the housing 105.

[0095] Of course, the method may include a step e) of adding the electrolyte 110 to the housing 105, in particular after steps c) and d), so as to add only the required quantity of electrolyte 110 to the housing 105, for example by filling the housing. This step e) is illustrated in particular in [Fig. 10] showing the housing 105 in which the electrolyte 110 and the roller 102 surrounding said at least one return element 101 are arranged.

[0096] The method may further include a step f) of sealing the housing 105. Step f) may consist of placing the cover 109 on the housing 105 and crimping it to the housing 105 (Figures 1, 3 and 4).

[0097] Step f) is implemented in particular to form a container (case 105 plus lid 109) that is leak-proof against the electrolyte 110 to prevent leakage of electrolyte 110 from the container to the outside of the container.

[0098] The manufacturing process may be such that the roller 102 provided for in step b) is integral with a winding mandrel 119 which has been used to form the roller 102 (see in particular in this regard [Fig.1 1], and that the winding mandrel 119 is removed before step c), in particular this removal corresponds to a disengagement of the winding mandrel 119 from the roller 102 and to an extraction of the winding mandrel 119 before inserting the roller 102 into the housing 105.

[0099] Thus, the multilayer 111 as shown in [Fig.5] can be wound onto the winding mandrel 119 prior to step b) in order to form the roll 102 which will be inserted into the housing in step c) after removal of the winding mandrel 119 from the roll 102. The removal of the winding mandrel 119 allows free access to the central volume 106 in order to insert, after inserting the roll 102 into the housing 105, said at least one return member 101 (step d)).

[0100] Preferably, step d) is such that said at least one return member 101 is inserted in a compressed state. This compression advantageously allows said at least one return member 101 to have a lateral dimension adapted to its insertion into the central volume 106 without damaging the roller 102, for example without generating friction against the internal surface 102a of the roller 102 delimiting the central volume 106. This is particularly visible in [Fig. 9].

[0101] Preferably, the compression of said at least one return element 101, so that it may be inserted into the housing 105, is such that it has dimensions allowing its insertion into the central volume 106 without touching the roller 102. For this purpose, said at least one compressed return element 101 may have lateral dimensions, measured orthogonally to its direction of insertion into the central volume 106, strictly less than the lateral dimensions of the central volume 106 measured orthogonally to the direction of insertion of said at least one compressed return element 101 in the central volume 106.

[0102] Then, after insertion of said at least one compressed return member 101 into the central volume 106, its compression can be released to allow its expansion in the central volume 106, resulting in the retention of the roller 102 thanks to the return force exerted by said at least one return member 101 on the roller 102.

[0103] In this description, "expansion of said at least one return element 101" means an expansion of the volume occupied by the latter. For example, an expansion of the foam corresponds to an increase in its volume; an expansion of the torsion spring, or where applicable, the helical spring, allows an increase in its diameter to ensure the aforementioned radial force.

[0104] For example, as shown in [Fig.9], step d) can be implemented using a gripping member such as a gripper 300. This gripping member, in addition to serving as a gripper for said at least one return member 101, allows, where appropriate, said at least one return member 101 to remain compressed by opposing its return effort.

[0105] When said at least one return member 101 is compressed by the gripping member, the separation of the gripping member from said at least one return member 101, then in place in the central volume 106, allows said at least one return member 101 to come into contact with the roller 102 in the central volume 106 ([Fig.8]) where it then exerts its return force.

[0106] The cell 100 finds an industrial application in the field of batteries, particularly for vehicles, a battery comprising a plurality of cells 100 as described.

[0107] The battery is, preferably, a battery for a motor vehicle and intended to serve as a source of energy for an electric motor of the motor vehicle enabling the movement of the motor vehicle, for example by propulsion or traction via two drive wheels of the vehicle, or by all-wheel drive via four drive wheels in particular when two electric motors, powered by the battery, are coupled respectively to a front axle of the motor vehicle comprising two of the wheels of the motor vehicle and to a rear axle of the motor vehicle comprising two other of the wheels of the motor vehicle.

Claims

Demands

1. Battery cell (100), said cell (100) comprising a housing (105) and a roller (102) housed in the housing (105), the roller (102) delimiting a central volume (106) around which said roller (102) is formed by winding, the roller (102) comprising electrodes (103, 104) of the cell (100), the cell (100) comprising at least one return element (101) arranged at least partially in the central volume (106), said at least one return element (101) exerting a return force on the roller (102) tending to ensure that the roller (102) is held between said at least one return element (101) and a wall (107) of the housing (105) of the cell (100), said at least one element (101) of return being a spring, characterized in that the spring is a torsion spring in the form of an element wound on itself and configured so as to produce a radial force enabling the roller (102) to be stressed towards the wall (107).

2. Cell (100) according to claim 1, wherein the retention of the roller (102) is ensured by compression of the roller (102) between said at least one return member (101) and the wall (107) of the housing (105).

3. Cell (100) according to any one of claims 1 to 2, wherein said at least return member (101) is configured so as to permit a variation of the volume occupied by the roller (102) around the central volume (106).

4. Cell (100) according to any one of claims 1 to 3, comprising a plurality of return elements (101) distributed in the central volume (106) along an axis of the roller (102).

5. Cell (100) according to claim 4, wherein the return members (101) are arranged so as to occupy at least 70% of the height of the roller (102) within the central volume.

6. Cell (100) according to any one of claims 1 to 3, wherein said at least one return member (101) is elongated and extends in the central volume (106) from a first longitudinal end (116) of the roller (102) to a second longitudinal end (117) of the roller (102), opposite the first longitudinal end (116) of the roller (102), so as to exert its return force over its entire length.

7. Cell (100) according to any one of claims 1 to 6, wherein said at least one return element (101) is made of steel.

8. Cell (100) according to any one of claims 1 to 7, wherein the return force of said at least one return element (101) is substantially radial to the winding axis of the roller (102) and oriented towards the wall (107) of the housing (105).

9. Cell (100) according to any one of claims 1 to 8, wherein the restoring force is omnidirectional around the winding axis (Al) of the roller (102) and directed towards the wall (107) of the housing (105).

10. A method for manufacturing a battery cell (100) according to any one of claims 1 to 9, comprising the following steps: a) providing the housing (105); b) providing the roller (102); c) inserting the roller (102) into the housing (105); d) inserting said at least one return element (101) into the central volume (106).

11. A manufacturing method according to claim 10, wherein step d) is such that said at least one return member (101) is inserted compressed.

12. A manufacturing method according to claim 11, wherein said at least one compressed return member (101) has lateral dimensions, measured orthogonally to its insertion direction in the central volume (106), strictly less than the lateral dimensions of the central volume (106) measured orthogonally to the insertion direction of said at least one compressed return member (101) in the central volume (106).

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