CH718209A2 - Battery with bonded joint and method of manufacturing such a battery. - Google Patents

Abstract

One aspect of the invention relates to a battery (100) comprising a housing having a container (111) defining a first pole of the battery, and a cover (112) defining a second pole of the battery, the container and the cover being sealed at the level of a contiguous zone (115) configured to ensure the tightness of the casing and the galvanic isolation between the said container and the said lid, the said container comprising a bottom crowned with a side wall (111-2) terminated at its end free by an end portion (111-3), said cover comprising an annular border (112-2), said battery being characterized in that said casing comprises an additional element (118) presenting: a first portion (118-1 ) extending in a first direction, said first portion being arranged so as to have at least a portion facing the annular edge (112-2) of the lid; a second portion (118-2), located inside the container, extending along a second direction not parallel to the first direction of said first portion, and configured to form an additional wall capable of reinforcing said side wall (111 -2) of the container. Another aspect of the invention is a method of manufacturing such a cell.

Description

Technical field of the invention

The field of the invention relates to electrochemical devices for converting chemical energy into electrical energy through a chemical redox reaction.

[0002] The invention relates more particularly to a battery, such as a button battery, and to its method of manufacture.

The invention finds a particularly interesting application in the field of watchmaking.

Technology background

[0004] Button cells generally comprise a casing containing electrochemical compounds forming an anode and a cathode, the casing being composed of two parts, a container and a cover, respectively forming the positive and negative poles of the cell.

[0005] Conventionally, the two parts are assembled via a preformed polymer gasket guaranteeing several functions: the holding in position of the two folded parts, the sealing of the battery and the galvanic isolation between the two poles. Such a construction is shown, for example, in GB 1566061.

This type of assembly using a polymer seal has the disadvantage of occupying a significant space which will restrict the internal active volume of the cell containing the electrolyte. In addition, this type of assembly requires a bending step to fold the upper part of the container against the lid and to compress the polymer seal in order to ensure the closure of the button battery as well as its sealing.

In an attempt to overcome these drawbacks, and in particular to increase the active volume of the button battery, it has been proposed to assemble the container and the cover by gluing, replacing the preformed gasket in thick polymer with a film of glue. positioned between the lid and the folded container.

[0008] However, the applicant has found that without the presence of a thick preformed polymer gasket, the step of folding the upper part of the container against the lid could damage the thin thickness of the adhesive film, leading to a lack of galvanic isolation between the two poles.

[0009] It has also been observed by the applicant that button cells comprising a thin film of adhesive, instead of a preformed polymer gasket, could have a sealing defect after closure.

[0010] In addition, the Applicant has also found that the step of closing button cells comprising a thin film of adhesive could damage the electrochemical compounds located inside the cell, and in particular the cathode.

Summary of the invention

[0011] In this context, the invention proposes a new button cell architecture comprising a glue joint and more particularly a thin film of glue as well as a new manufacturing process making it possible to ensure perfect galvanic isolation between the cover and the container after closing the case.

The invention also makes it possible to ensure good cohesion between the lid and the container so as to guarantee the tightness of the button battery.

The invention also has the advantage of guaranteeing the integrity of the electrochemical compounds, and in particular the cathode, positioned inside the casing of the button cell, when the container is closed on the lid.

To this end, the invention relates to a battery comprising a housing having a container defining a first pole of the battery, and a lid defining a second pole of the battery, the container and the lid being sealed at the level of a contiguous zone configured to ensure the tightness of the casing and the galvanic isolation between the said container and the said lid, the said container comprising a bottom crowned with a side wall terminated at its free end by an end portion, the said lid comprising an annular edge, said battery being characterized in that said casing comprises an additional element having: a first portion extending in a first direction, said first portion being arranged so as to have at least one part facing the annular edge of the cover; a second portion, located inside the container, extending along a second direction not parallel to the first direction of said first portion, and configured to form an additional wall capable of reinforcing said side wall of the container.

Advantageously, said second portion of the additional element has a free end in abutment with said container.

[0016] In addition to the characteristics mentioned in the previous paragraph, the button battery according to the invention may have one or more additional characteristics from among the following, considered individually or in all technically possible combinations: the free end of the second portion of the additional element is in abutment with the bottom of the container; the additional element is of annular shape; the additional element is metallic or made of synthetic material; the additional element is a bent sheet metal; the additional element is made of steel based on iron and carbon, stainless steel or else an alloy of iron and nickel; the material of said additional element is identical to the material of said container and/or of said lid and/or in that said additional element has a thickness identical to the thickness of said container and/or of said lid; the second portion of the additional element extends parallel to the side wall of the container; the second portion of the additional element has a first surface in contact with the side wall of the container; the housing delimits a first compartment receiving a first electrode and a second compartment receiving a second electrode, the first electrode and said second electrode being separated by an ion-conducting separator, said first electrode being a compacted porous electrode; the second portion of the additional element extends between said side wall of the container and said first electrode; the second portion of the additional element has a second surface in contact with the first electrode; the contiguous zone comprises an adhesive layer able to ensure at least the galvanic insulation between the container and the lid; said first portion of said additional element extends between the annular edge of the lid and the end portion of the container; the glue layer is positioned at the junction between the annular edge of the lid and the first portion of the additional element; the glue layer is positioned at the junction between the end portion of the container and the first portion of the additional element; said first portion of said additional element faces the separator; the first portion of said additional element comprises a surface in contact with the separator; the additional element is housed entirely in the first compartment receiving the first electrode; the first electrode has a peripheral shoulder, such that the section of said first electrode at the level of said peripheral shoulder is reduced, said peripheral shoulder of the first electrode being configured to receive said first portion of the additional element.

[0017] Advantageously, the additional element is a protective element of the first porous electrode.

The invention also relates to a method of manufacturing a battery according to the invention comprising a step of closing said casing by deforming the end portion of the container.

[0019] Advantageously, the process for manufacturing a battery according to the invention comprises a step of supplying a container, a cover and an additional element, in particular by cutting, bending metal sheets.

[0020] Advantageously, the process for manufacturing a battery according to the invention comprises a step of at least partially filling said container with a first electrode and a liquid active material.

Advantageously, the method of manufacturing a battery according to the invention comprises a step of positioning said additional element around said first electrode positioned in said container.

[0022] Advantageously, the process for manufacturing a battery according to the invention comprises a step of sealing the casing at the level of said contiguous zone between the container and the cover.

Advantageously, the method of manufacturing a battery according to the invention comprises a step of securing said additional element to the annular edge of the cover by bonding using a layer of glue.

[0024] Advantageously, the step of sealing the casing at said contiguous zone between the container and the lid is carried out by folding the end portion of the container onto said additional element.

[0025] Advantageously, the method comprises, prior to the step of sealing the casing, a step of positioning an annular seal between the container and said additional element, the step of sealing the casing at the level of said contiguous zone between the container and the lid made by folding the end portion of the container onto said additional element, compressing said annular seal.

Brief description of figures

The aims, advantages and characteristics of the present invention will appear on reading the detailed description below referring to the following figures: Figure 1 is a schematic representation in radial section of a first embodiment of a battery according to the invention, such as a button battery; FIG. 2 shows in perspective an embodiment of an additional element of a button battery according to the invention, in partial section; FIG. 3 is a schematic representation in radial section of a second embodiment of a button battery according to the invention; FIG. 4 is a schematic representation of the button battery according to the invention, according to the first example embodiment illustrated in FIG. 1, before closing and sealing of the casing; FIG. 5 schematically illustrates the step of closing the casing and sealing the casing of the button battery illustrated in FIG. 1; Figure 6 is a block diagram illustrating the main steps of the manufacturing process of the button battery shown in Figure 1; Figure 7 is a block diagram illustrating the main steps of the manufacturing process of the button battery shown in Figure 3.

In all the figures, the common elements bear the same reference numbers unless otherwise specified.

Detailed description of the invention

The present invention relates to a battery comprising a casing conventionally provided with two parts respectively defining the positive pole and the negative pole of the battery as well as to its method of manufacture.

It may be a button battery but the present invention is also applicable to other types of batteries such as sachet batteries, thin film batteries, and more generally all batteries of the state of the technique assembled by crimping compressing a preformed polymer seal or by applying a layer or film of insulating adhesive at the junction between these two poles.

The invention relates particularly to cells and batteries having a porous electrode composed of an agglomerated powder, and more particularly to cells and batteries having a porous cathode.

A first embodiment of a battery according to the invention is shown schematically in Figure 1, in radial section.

The cell 100 shown in Figure 1 is a button cell.

The button cell 100 has an axis of revolution Oz around which the button cell 100 has a symmetry of revolution. Throughout the description and in the claims, the terms "lower", "internal", "upper", "external" are used in reference to a direction parallel to the axis of revolution Oz so that a surface lower (or inner) surface of a cell is closer to the bottom of button cell 100 than a upper (or outer) surface of the same cell. The terms "radially inner" and "radially outer" are used in reference to a radial direction perpendicular to the axis of revolution Oz of the button cell, so that a radially inner surface is closer to the axis of revolution Oz than a radially outer surface.

The button cell 100 comprises a casing 110 composed of a first part 111 and a second part 112 respectively forming the positive and negative poles of the button cell 100.

In the embodiment illustrated in Figure 1, the first part 111 forms a container of the housing 110 and the second part 112 forms a cover of the housing 110.

The container 111 comprises a bottom 111-1 crowned with a side wall 111-2 having at its free end an end portion 111-3 intended to be folded down by folding to cooperate with the lid 112 and thus close the casing 110 at a contiguous zone 115 via a layer of glue 117. In FIG. 1, the end portion 111-3 is shown in its final folded position.

In the embodiment illustrated in Figure 1, the side wall 111-2 extends in a direction substantially perpendicular to the bottom 111-1. However, other embodiments are also considered.

Preferably, the container 111 is a single piece, made by cutting, bending a metal sheet.

The cover 112 has a central portion 112-1 and an annular border 112-2 surrounding the central portion 112-1. The central portion 112-1 of the cover 112 protrudes with respect to the annular border 112-2, so that the central portion 112-1 is configured to delimit an internal compartment 160 capable of receiving part of the electrochemical compounds of the cell. button 100, and more particularly the anode 114.

[0040] Preferably, the cover 112 is a single piece made by cutting, bending a metal sheet.

As described above, the cover 112 and the container 111 are sealed in a leaktight manner at the level of the contiguous zone 115, in particular by means of a layer or a film of glue 117.

In the embodiment illustrated in Figure 1, the layer of glue 117 is deposited at the interface of the annular edge 112-2 of the lid 112 and the end portion 111-3 of the container 111.

At this contiguous zone 115, the annular edge 112-2 of the lid 112 has an upper surface, and the end portion 111-3 of the container 111 has a lower surface, the two surfaces having corresponding shapes of so as to be substantially parallel. The glue layer 117 is positioned between the upper surface of the annular rim 112-2 of the cover 112 and the lower surface of the end portion 111-3 of the container 111 and forms a bonding interface.

The glue layer 117 has properties to ensure the electrical insulation between the container 111 and the lid 112, as well as to possibly ensure the tightness of the button battery 100 vis-à-vis the various electrochemical compounds, encapsulated inside the case 110, and which are necessary for the operation of the button battery 100 and for the setting up of a chemical reaction of redox.

The glue used for the glue layer 117 is preferably an epoxy glue, or an acrylate glue. However, other types of glue can be envisaged, for example glues based on silicone or polyurethane, since they make it possible to seal the container 111 and the lid 112 in a leaktight manner and to ensure electrical insulation between the container 111 and the cover 112. It goes without saying that the glue selected must also be chemically insensitive to the internal electrolyte of the battery.

The adhesive layer 117 advantageously has a substantially constant thickness, typically between 30 μm and 200 μm, preferably between 50 μm and 200 μm.

[0047] By way of example, the thickness of the adhesive layer is of the order of 100 μm.

The thickness of the adhesive layer 117 can be controlled by adding spacers at the bonding interface (not shown) as mentioned in particular in patent application EP 18 152 829.

In order to improve the adhesion of the layer of adhesive 117, the surfaces to be assembled at the level of the contiguous zone 115 may optionally have been treated, or even functionalized before the deposition of the layer of adhesive 117, as described for example in application EP 19 190 795.

More specifically, the surfaces to be assembled can be subjected to reactive sandblasting, also called silicatization, which consists in sandblasting the surface with silica-coated alumina grains. This results in the deposition of a silicatized layer. Then, the surfaces to be assembled can optionally be functionalized by depositing an adhesion promoter comprising, for example, silane groups, the alkoxyl functions of which are intended to form a chemical bond with the deposited silicatized layer, and comprising other functions intended to chemically bond with the glue. Depending on the type of glue used, it can, for example, be amine or acrylate groups. It will be noted that an adhesion promoter can be provided on the surfaces to be bonded without prior sanding.

The housing 110 defines a first compartment 150 capable of receiving a first electrode 113 forming the cathode and a second compartment 160 capable of receiving a second electrode 114 forming the anode. The two electrodes 113, 114 are physically separated from each other by an ion-conductive separator 116, the cathode 113 and the anode 114 having at least one surface in contact with the separator 116. The housing 110 also contains a solution electrolyte conductor in which the two electrodes 113 and 114 are immersed.

Conventionally, and as shown in Figure 1, the cathode 113 is formed in a preferably lower region of the button battery 100, and is in electrical contact with the container 111, more particularly with the bottom 111-1 of the container 111. The anode 114 is formed in a preferably upper region of the button battery 100, and is in electrical contact with the cover 112.

However, the invention is not limited to such a representation, and other representations can also be considered without departing from the scope of the invention.

The button cell 100 is for example a lithium button cell having an anode 114 composed of lithium, a porous cathode 113 composed of manganese dioxide.

Conventionally, the porous cathode 113 is produced separately by compacting from a ceramic powder, for example a manganese dioxide powder. The compacting method used for producing the porous cathode 13 is a conventional compacting method known to those skilled in the art. Thus, it is not necessary to further detail the process for compacting a porous electrode from a ceramic powder.

The button battery 100 according to the invention further comprises an additional element 118, forming a third part of the case 110, configured in particular to facilitate the sealing operations of the case 110 as well as to avoid deterioration of the thin layer of glue. 117 when folding the end portion 111-3 of the container 111 on the lid 112.

The additional element 118 is a reinforcing element configured to make it possible to absorb and/or deflect (by load transfer) at least part of the forces generated on the casing 110 during the closing operation of the stack 100.

Thus, the additional element 118 makes it possible to ensure and guarantee perfect galvanic isolation between the cover 112 and the container 111 after encapsulation by avoiding damage to the thin layer of glue 117, unlike batteries and methods of the state of the art.

The additional element 118 also makes it possible to guarantee the structural integrity of the porous cathode 113.

The additional element 118 has, for example, a generally annular shape, an annular ring or even a ring.

For example, there is shown in Figure 2 an embodiment of an additional element 118 according to the invention. Figure 2 illustrates the additional element in a perspective view with a radial section.

Preferably, the additional element 118 has, along a radial section plane, an asymmetrical section. However, the additional element 118 can also have a symmetrical section.

In the embodiment illustrated in Figure 1 and Figure 2, the additional element 118 has an asymmetrical section in the shape of an inverted L.

Of course, other shapes and variants of the additional element 118 are possible depending on the shape and dimensions of the battery without departing from the scope of the invention.

The additional element 118 comprises a first portion 118-1, forming an upper portion of length L1 extending in a first direction. Preferably, the first portion 118-1 has at least one surface substantially parallel to a surface of the annular edge 112-2 of the cover 112, in particular at the level of the bonding interface at the level of the contiguous zone 115.

Preferably, the first portion 118-1 extends parallel to the peripheral edge 112-2 of the cover 112.

The additional element 118 further comprises a second portion 118-2, forming a lateral portion of the additional element 118 of length L2 extending in a second direction not parallel to the first direction of the first portion 118- 1.

The two portions 118-1 and 118-2 of the additional element 118 are connected by a connection section 118-3 in an arc of a circle having a concave surface at its internal surface, thus forming a fillet.

Preferably the outer surface of the connection section 118-3 is also arcuate and has a convex section.

Preferably, the connection section 118-3 has a radius of curvature, at its internal surface, at least equal to the thickness of the additional element 118. For example, the radius of curvature is greater or equal to 0.2 mm, for example between 0.2 mm and 0.5 mm.

The additional element 118 is advantageously made by cutting, bending a metal sheet.

The second portion 118-2 has at least one surface parallel to the side wall 111-2 of the container 111.

Preferably, at least a portion of the second portion 118-2 of the additional element 118 extends parallel to the side wall 111-2 of the container 111.

Preferably, at least a portion of the second portion 118-2 of the additional element 118 extends between the side wall 111-2 of the container 111 and the cathode 113.

In the embodiment illustrated in Figures 1 to 3, the first portion 118-1 and the second portion 118-2 of the additional element 118 extend in two different directions, substantially perpendicular.

In the first embodiment illustrated in Figure 1, the additional element 118 is fully housed inside the housing 110, preferably in a peripheral region of the housing 110, and more specifically in a peripheral region of the container 111 , so that the additional element 118, and more particularly the first portion 118-1, has at least one portion facing the contiguous zone 115 between the container 111 and the lid 112, and in particular facing opposite the annular edge 112-2 of the cover 112.

In this first embodiment, the additional element 118 is positioned more particularly opposite the separator 116, and more particularly under the separator 116, and therefore in the compartment 150 receiving the porous electrode, more particularly the cathode 113 compacted porous.

The inverted L shape of the additional element 118 advantageously allows it to be positioned around the porous cathode 113 so as to encircle the latter. Thus, the L-shape facilitates the positioning of the additional element 118 during the assembly of the stack 100 and the integration of an additional element 118 does not complicate the manufacturing steps of such a stack 100.

The second portion 118-2 has a first surface 118-21, formed by the radially outer surface of the second portion 118-2, in contact with at least a part, for example the lower part, of the side wall 111 -2 of the container 111. More particularly, the second portion 118-2 of the additional element 118 is in contact with at least part of the radially inner surface of the side wall 111-2 of the container 111.

The second portion 118-2 thus positioned makes it possible to constitute a second peripheral wall of the casing 110, or additional wall, which stiffens and reinforces at least a part of the side wall 111-2 of the container 111. The second portion 118- 2 forms an additional support located inside the housing 110 making it possible to prevent the deformation of the side wall 111-2, and in particular of the lower portion thereof, during the deformation and folding of the portion of end 111-3.

[0081] Consequently, the additional element 118 constitutes a means of reinforcing the casing 110 making it possible to better control the deformation of the side wall 111-2, and in particular of the end portion 111-3 during the operation of closing of the case 110 consisting of the folding of the end portion 111-3 of the container 111 onto the lid 112.

[0082] Indeed, by limiting and controlling the deformation of the side wall 111-2, and in particular of its lower portion, during the operation of closing the case 110, it is possible to control and further control the deformation and the final position of the end portion 111-3 of the container 111, and therefore to ensure a good positioning of the end portion 111-3 parallel to the layer of glue 117 while minimizing the closing force necessary for the enclosure encapsulation.

Thus, thanks to the invention, it is possible to guarantee in a repeatable manner a sealing of the casing 110 and an electrical insulation of the latter while using a thin layer or film of glue 117 instead of a seal. thick polymer.

The additional element 118 makes it possible to limit the unwanted deformation of the side wall 111-2 and to overcome any excessive deformation of the end portion 111-3 and/or the application of a excessive closing force at this end portion 111-3 risking damaging the adhesive layer 117 by pinching, tearing or even by punching it by the end portion. Thus, the electrical insulation between the container 111 and the lid 112 and/or the tightness of the case 110 are preserved.

In this first embodiment, the length L2 of the second portion 118-2 is substantially equal to the height H of the porous cathode 113, so that the upper surface of the first portion 118-1 of the element additional 118 is found substantially at the same level as the upper surface 113-2 of the cathode 113. Thus, the upper surface of the first portion 118-1 is advantageously in contact with the separator 116, and more particularly with the lower surface of the separator 116.

Such an architecture of the additional element 118 also makes it possible to limit the deformation of the peripheral portion of the separator 116 when the casing 110 is closed, by structural stiffening. Indeed, the additional element 118 forms a reinforcement and an additional support at the level of the peripheral end of the separator 116, located opposite the zone of application of the closing force.

Thus, thanks to the first portion 118-1 located under the separator 116 and facing the contiguous zone 115 on which a closing force is applied, the deformation of the separator 116 is minimized but also of the annular border 112- 2 of the cover 112 when closing the case 110.

By controlling the position of the annular edge 112-2 of the cover after the housing 110 has been closed, it is possible to guarantee the parallelism of the surfaces of the bonding interface, and more particularly of the annular edge 112-2 and of the end portion 111-3 in its final position (i.e. after folding), and therefore the galvanic isolation and sealing of the button battery 100.

According to a variant embodiment, the length L2 of the second portion 118-2 is slightly less than the height H of the cathode 113, that is to say that the length L2 corresponds for example between 90% and 100 % of the height H of the cathode 113. Thus, when assembling the button battery 100, contact between the cathode 113 and the separator 116 is guaranteed at the level of the upper surface 113-2, while accepting a possible deformation very limited of the separator 16 which can intervene during the step of closing the case 110.

[0090] Preferably, the lower end of the additional element 118 is in abutment so as to avoid any movement of the additional element 118 inside the housing 110, in particular during the application of the closing force on the casing 110. The additional element 118 is for example supported on the bottom 111-1 of the container 111. Thus, the recovery of the compression forces generated on the upper part of the casing 110 during the closing operation is optimized, and the deformation of the separator 116 as well as the deformation of the annular edge 112-2 of the lid 112 is further minimized so as to maintain the surfaces of the bonding interface parallel at the level of the contiguous zone 115.

In such a configuration, the additional element 118 has the function of a cathode protective element 113 configured to absorb at least part of the compressive forces generated on the casing 110 during the closing operation and to achieve a transfer of charge to the bottom 111-1 of the container 111. The protective element 118 thus makes it possible to avoid the crushing of the internal volume of the casing 110 and therefore the degradation of the structure of the compacted porous cathode 113 located in the lower region of the case 110 during the closing operation of the stack 100.

Thus, the additional element 118 according to the invention forms a protective screen capable of guaranteeing the structural integrity of the porous cathode 113 after the encapsulation operation.

Preferably, the first portion 118-1 of the additional element 118 extends substantially in a direction perpendicular to the closing force F applied to the housing 110 during the closing operation of the housing 110 as shown in figure 5.

Preferably, the second portion 118-2 of the additional element 118 extends substantially in a direction parallel to the closing force F applied to the housing 110 during the closing operation of the housing 110.

Preferably, the radially inner surface 118-22 of the second portion 118-2 of the additional element 118 is directly in contact with the porous cathode 113, and more particularly with the peripheral side of the cathode 113. Thus, the second portion 118-2 makes it possible to support the side of the porous cathode 113, in particular during the operation of closing the casing 110, so as to avoid possible degradation by shearing of the peripheral end of the porous cathode 113, during the application of a substantially vertical closing force F as shown in Figure 5.

Preferably, the compacted cathode 113 has at its upper surface 113-2, that is to say at the level of the surface facing the separator 116, a peripheral shoulder 113-1 so that the cathode 113 has a section (along a radial plane) reduced at the level of the peripheral shoulder 113-1. The peripheral shoulder 113-1 thus provided at the level of the cathode 113 reduces the portion of the upper surface 113-2 in contact with the separator 116 but advantageously makes it possible to provide a peripheral space making it possible to accommodate at least a portion of the element additional 118, and more particularly the first portion 118-1.

In the embodiment illustrated in Figure 1, the peripheral shoulder 113-1 is formed over the entire peripheral periphery of the cathode 113.

[0098]Preferentially, provision is made for a clearance between the first portion 118-1 of the additional element 118 and the upper surface of the cathode 113 at the level of the peripheral shoulder 113-1, in particular finally to avoid any risk of degradation of the cathode 113 during a possible deformation of the additional element 118 when closing the case 110.

The additional element 118 is, for example, made of metallic material and shaped from sheet metal by bending.

The additional element 118 is for example made of a material identical to the material used for the production of the container 111 and the lid 112.

The additional element 118 is for example made of steel based on iron and carbon, stainless steel or even an alloy of iron and nickel.

The container 111 and the lid 112 are for example made of steel based on iron and carbon, stainless steel or even an alloy of iron and nickel.

The additional element 118 has, for example, a thickness substantially equivalent to the thickness of the sheets used for the production of the cover 112 and of the container 111 of the housing 110. By substantially equivalent is meant a value comprised in an interval of +/- 20%.

[0104] Preferably, the additional element 118 has a thickness equal to the thickness of the sheets used to make the cover 112 and the container 111 of the box 110. Thus, the material supply costs are reduced.

For example, the additional element 118 made of metallic material has a thickness of 0.2 mm.

[0106] In general, the thickness, the shape and the dimensions of the additional element 118 will be determined so that it makes it possible to absorb at least part of the forces generated on the housing 110 during closing operation of stack 100. By way of example, reinforcing element 118 according to the invention is configured to absorb and/or deflect between 30% and 60% of the forces exerted on housing 110 during the closing operation. closure, preferably between 40% and 50%.

According to a variant embodiment, the additional element 118 can also be made of synthetic material, for example by plastic injection. In this case, the additional element 118 will have a greater thickness than that mentioned above for an additional element made of metallic material, so as to be able to take up and withstand the forces mentioned above when closing the case 110, while limiting the elastic deformation of the additional element 118 so as not to damage the cathode 113.

Unlike an additional element made of plastic material, the use of an additional element 118 made of metallic material has the advantage of minimizing the thickness of the latter and therefore of being able to optimize the quantity of electrochemical compounds inside. of the case, and consequently the electrical capacity of the button cell 100 for an identical external size.

[0109] Figure 3 illustrates a second embodiment of a battery according to the invention. FIG. 3 more specifically illustrates a cross-sectional view, along a radial plane, of a second embodiment of a cell 200 according to the invention.

In this second embodiment, battery 200 is also a button battery. The button battery 200 is identical to the button battery 100 described previously except for the characteristics which will be described in the following paragraphs.

In this second exemplary embodiment, the button battery 200 comprises a casing 210 composed of a container 111 and a cover 112 respectively forming the positive and negative poles of the button cell 200 in an identical manner to the first exemplary embodiment. shown in Figure 1.

The housing 210 also comprises an additional element 218 having, along a radial section plane, an asymmetrical section in the shape of an inverted L. The additional element 218 comprises a first portion 218-1, forming an upper portion, and a second portion 218-2 forming a side portion.

In this second embodiment, the additional element 218 is not housed entirely inside the housing 210, in particular under the separator 116, as described above, but has a first portion 218-1 positioned above of the separator 116.

Preferably, the first portion 218-1 of the additional element 218 extends between the folded end portion 111-3 and the annular edge 112-2 of the cover 112, so that the first portion 218-1 is sandwiched between the folded end portion 11-3 of the container 111 and the annular edge 112-2 of the lid 112.

The glue layer 117 is positioned on one of the surfaces of the first portion 218-1 of the additional element 218 between the folded end portion 111-3 and the annular edge 112-2 of the cover 112.

[0116] According to a first variant embodiment, the adhesive layer 117 is positioned on the upper surface of the first portion 218-1 so that the adhesive layer 117 is positioned at the junction between the first portion 218-1 and the end portion 111-3 of the container 111 in its folded position.

In this first variant embodiment, the sealing of the case 210 is carried out in an identical manner to the first example embodiment described with reference to FIG. 1, that is to say when the case is closed by folding of the end portion 111-3 of the container 111.

[0118] According to a second variant embodiment, illustrated more particularly in FIG. 3, the layer of glue 117 is positioned on the lower surface of the first portion 218-1 so that the layer of glue 117 is positioned at the junction between the first portion 218-1 and the annular edge 112-2 of the cover 112, as shown in Figure 3.

In this second variant embodiment, the additional element 218 is secured beforehand to the cover 112 by means of the layer of glue 117, the bonding of the additional element 118 and of the cover being carried out during a step prior to the step of folding the end portion 111-3 of the container.

The bonding of the additional element 218 and of the annular edge 112-2 of the cover 112 is carried out by pressing the two parts and by bringing them to temperature until polymerization or complete bonding of the glue, according to pressure conditions. and temperature required depending on the glue used. Preliminary bonding, that is to say before the operation of encapsulating the box 210, makes it possible to ensure an optimum bonding interface without deformation and without risk of detachment or tearing at the level of the interface. lift-off. Such a variant makes it possible, for example, to overcome the problems of folding and positioning of the end portion 111-3. It also makes it possible to avoid possible problems of bringing the electrochemical elements of the cell to temperature during the optimum polymerization of the glue chosen.

This alternative embodiment also has the advantage of minimizing the size inside the case 210 by avoiding the positioning of the first portion 218-1 inside the useful internal volume of the battery 200, thus leaving more space for the electrochemical compounds of the button battery 200. Thus, the electrochemical performance of the battery 200 is optimized.

In this variant embodiment, it is possible to add an additional sealing element, such as an annular seal 250 so as to ensure the complete sealing of the battery 200 vis-à-vis the electrolyte. present inside the housing 210. Preferably, the annular seal 250 is positioned between the additional element 218 and the container 111, before folding down the end portion 113.

In a third embodiment (not shown), the first portion of the additional element is located between the separator 116 and the annular edge 112-2 of the cover 112, so that the first portion of the additional element is sandwiched between the separator 116 and the annular edge 112-2 of the cover 112.

In this third embodiment, the layer of glue 117 is positioned between the lower surface of the annular edge 112-2 of the cover and the upper surface of the first portion of the additional element.

In this third exemplary embodiment, the additional element 218 is also secured beforehand to the cover 112 via the layer or film of adhesive 117, as described above with reference to the second exemplary embodiment.

[0126] Figure 6 schematically illustrates the main steps of the manufacturing process 300 of a button battery 100 according to the invention.

A step 310, called the first step, consists in procuring pre-cut metal sheets and shaping said metal sheets so as to obtain a container 111a in a non-final shape, that is to say with the end portion 111-3 not folded down as shown in Figure 4, a cover 112 and an additional element 118.

The container 111a in its non-final shape typically has a U-shaped section.

A step 320, called the second step, consists in positioning the various elements constituting the stack 100 inside the container 111a obtained during the previous step, namely: a first solid active material, such as the cathode 113, previously compacted, the cathode being in electrical contact with the bottom 111-1 of the container 111a; the additional element 118 shaped so that the additional element 118 surrounds the cathode 113 and at least partially caps a peripheral portion of the cathode 113, as shown in FIG. 4; separator 116 on cathode 113; a liquid active material, such as the electrolyte.

The cathode 113 and the additional element 118 can be positioned successively inside the container 111a, or can be assembled beforehand before their positioning in the container 111a so as to form an assembly. The pre-assembly is notably facilitated by the presence of the peripheral shoulder 113-1 provided on the periphery of the cathode 113 thus allowing a preliminary fitting of the additional element 118 on the cathode 113. Thus, the additional element 118 is already positioned around the cathode 113. The positioning of the additional element 118 is then facilitated.

A step 330, called the third step, consists of positioning and securing a second solid active material, such as the anode 114 in the cover 112, and more particularly at the level of the internal compartment formed by the central portion 112-1. The anode 114 is secured for example by gluing. This step 330 can be carried out after or before the second step 320 described above.

A step 340, called the fourth step, consists in positioning the cover 112 with the anode 114 on the separator 116.

A step 350, called the fifth step, consists in depositing a layer or a film of glue 117 on the upper surface of the annular edge 112-2 of the cover 112 so as to form the bonding interface.

[0134] A step 360, called the sixth step, is a step of encapsulating or sealing the case 110 consisting in folding the end portion 111-3 of the container 111 to fold it over the lid 112, and in particular over the layer glue 117 in order to close the case 110. This encapsulation step is more particularly shown in Figure 5.

[0135] The deformation of the end portion 111-3 is carried out conventionally by the use of one or more shaped tools having one or more cavities adapted to gradually guide the deformation of the end portion 111-3 so as to bring it into a position substantially parallel to the upper surface of the annular edge 112-2 of the lid 112 on which the layer of glue 117 has been previously deposited.

[0136] Figure 7 illustrates the main steps of the manufacturing process 400 of the second embodiment described above with reference to Figure 3. This manufacturing process 400 of a button battery 200, has slightly different steps compared to the process manufacturing 300 which has just been described.

A step 410, called the first step, consists in procuring pre-cut metal sheets and shaping said metal sheets so as to obtain a container 111a in a non-final shape, that is to say with the end portion 111-3 not folded down as shown in Figure 4, a cover 112 and an additional element 218.

A step 420, called the second step, consists in positioning the various elements constituting the stack 200 inside the container 111a obtained during the previous step, namely: A first solid active material, such as the cathode 113, previously compacted, the cathode being in electrical contact with the bottom 111-1 of the container 111a; separator 116 on cathode 113; a liquid active material, such as the electrolyte.

In this variant embodiment, it will be noted that the additional element 218 is not positioned with the cathode 113.

In a step 430, called the third step, which can occur before the second step 420 or after the second step 420, the layer, or the film, of glue 117 is positioned on the cover 112, and more particularly at the level of the annular edge 112-2, and even more particularly on the upper surface of the annular edge 112-2 of the cover 112.

In a step 440, called the fourth step, carried out after the third step 430, the additional element 218 is secured to the cover 112 via the layer of glue 117. This securing step is preferably carried out under required pressure conditions and temperature depending on the glue used.

In a step 450, called the fifth step, the anode is positioned and secured in the cover 112, and more particularly at the level of the internal compartment formed by the central portion 112-1. The anode 114 is secured for example by gluing. This step 450 can be carried out after the fourth step 440 or even before the third step 430.

In a step 460, called the sixth step, of encapsulation or sealing of the casing 210, the casing 210 is closed by folding the end portion 111-3 of the container 111, so as to fold it over the element additional 218, and more particularly on the upper surface of the upper portion 218-1.

[0144] Optionally, the method 400 may include a step 470, called the seventh step, consisting in positioning an annular seal 250 on the periphery of the container 111a making it possible to provide additional sealing vis-à-vis the electrolyte contained in the case. 210.

Claims (25)

1. Battery (100, 200) comprising a housing (110, 210) having a container (111) defining a first pole of the battery, and a cover (112) defining a second pole of the battery, the container (111) and the lid (112) being sealed at the level of a contiguous zone (115) configured to ensure the tightness of the casing (110, 210) and the galvanic isolation between the said container (111) and the said lid (112), the said container (111) comprising a bottom (111-1) crowned with a side wall (111-2) terminated at its free end by an end portion (111-3), said cover (112) comprising an annular border (112 -2), said battery (100, 200) being characterized in that said housing (110, 210) comprises an additional element (118, 218) having: – a first portion (118-1, 218-1) extending in a first direction, said first portion being arranged so as to have at least one part facing the annular edge (112-2) of the cover (112); – a second portion (118-2, 218-2), located inside the container (111), extending in a second direction not parallel to the first direction of said first portion (118-1, 218-1 ), and configured to form an additional wall capable of reinforcing said side wall (111-2) of the container (111). 2. Battery (100, 200) according to the preceding claim, characterized in that said second portion (118-2, 218-2) of said additional element (118, 218) has a free end in abutment with said container (111). 3. Battery (100, 200) according to one of the preceding claims, characterized in that said free end of the second portion (118-2, 218-2) of the additional element (118, 218) is in abutment with the bottom (111-1) of the container (111). 4. Battery (100, 200) according to one of the preceding claims, characterized in that said additional element (118, 218) is of annular shape. 5. Battery (100, 200) according to one of the preceding claims, characterized in that said additional element (118, 218) is metallic or made of synthetic material. 6. Battery (100, 200) according to the preceding claim characterized in that said additional element (118, 218) is a bent sheet metal. 7. Battery (100, 200) according to the preceding claim, characterized in that said additional element (118, 218) is made of steel based on iron and carbon, stainless steel or else an alloy of iron and nickel. 8. Battery (100, 200) according to one of the preceding claims, characterized in that the material of said additional element (118, 218) is identical to the material of said container (111) and/or of said lid (112) and/or in that said additional element (118, 218) has a thickness identical to the thickness of said container (111) and/or of said cover (112). 9. Battery (100, 200) according to one of the preceding claims, characterized in that said second portion (118-2, 218-2) of the additional element (118, 218) extends parallel to the side wall (111-2) of the container (111). 10. Battery (100, 200) according to one of the preceding claims, characterized in that said second portion (118-2, 218-2) of the additional element (118, 218) has a first surface (118-21 ) in contact with the side wall (111-2) of the container (111). 11. Battery (100, 200) according to one of the preceding claims, characterized in that said housing (110, 210) defines a first compartment (150) receiving a first electrode (113) and a second compartment (160) receiving a second electrode (114), the first electrode (113) and said second electrode (114) being separated by an ionically conductive separator (116), said first electrode (113) being a compacted porous electrode. 12. Battery (100, 200) according to claim 11, characterized in that said second portion (118-2, 218-2) of the additional element (118, 218) extends between said side wall (111-2 ) of the container (111) and said first electrode (113). 13. Battery (100, 200) according to one of claims 11 to 12, characterized in that said second portion (118-2, 218-2) of the additional element (118, 218) has a second surface (118 -22) in contact with the first electrode (113). 14. Battery (100, 200) according to one of the preceding claims, characterized in that said contiguous zone (115) comprises an adhesive layer (117) capable of ensuring at least the galvanic insulation between the container (111) and the lid. (112). 15. Battery (100, 200) according to one of the preceding claims, characterized in that said first portion (218-1) of said additional element (218) extends between the annular edge (112-2) of the cover (112) and the end portion (111-3) of the container (111). 16. Battery (100, 200) according to claim 14 and 15, characterized in that said adhesive layer (117) is positioned at the junction between the annular edge (112-2) of the cover (112) and the first portion ( 218-1) of the additional element (218). 17. Battery (100, 200) according to claim 14 and 15, characterized in that said adhesive layer (117) is positioned at the junction between the end portion (111-3) of the container (111) and the first portion (218-1) of the additional element (218). 18. Cell (100, 200) according to one of claims 11 to 14, characterized in that said first portion (118-1) of said additional element (118) faces the separator (116). 19. Cell (100, 200) according to the preceding claim, characterized in that said first portion (118-1) of said additional element (118) comprises a surface in contact with the separator (116). 20. Battery (100, 200) according to one of claims 18 to 19, characterized in that said additional element (118) is housed entirely in the first compartment (150) receiving the first electrode (113). 21. Cell (100, 200) according to the preceding claim, characterized in that said first electrode (113) has a peripheral shoulder (113-1), so that the section of said first electrode (113) at the level of said peripheral shoulder (113-1) is reduced, said peripheral shoulder (113-1) of the first electrode (113) being configured to receive said first portion (118-1) of the additional element (118). 22. Manufacturing method (300, 400) of a battery (100, 200) according to one of claims 1 to 21 characterized in that it comprises: – a step (310, 410) of supplying a container (111), a lid (112) and an additional element (118, 218), - a step (320, 420) of at least partially filling said container (111) with a first electrode (113) and a liquid active material; – a step of positioning said additional element (118, 218) around said first electrode (113) positioned in said container (111) during the previous step; – a step (360, 460) of sealing the casing (110, 210) at the level of said contiguous zone (115) between the container (111) and the lid (112). 23. A method of manufacturing (300, 400) a battery (100, 200) according to the preceding claim characterized in that prior to the step (460) of sealing, the method comprises a step (440) of securing said element additional (218) on the annular edge (112-2) of the cover (112) by bonding using a layer of glue (117). 24. Manufacturing method (300, 400) of a battery (100, 200) according to the preceding claim, characterized in that the step (460) of sealing the casing (210) at the level of the said contiguous zone (115) between the container (111) and the lid (112) is made by folding the end portion (111-3) of the container (111) onto said additional element (218). 25. A method of manufacturing (300, 400) a battery (100, 200) according to one of claims 21 to 22 characterized in that the method comprises, prior to the step (460) of sealing the casing (210 ), a step (470) of positioning an annular gasket (250) between the container (111) and said additional element (218), the step (460) of sealing the casing (210) at the level of said joined zone (115) between the container (111) and the lid (112) produced by folding the end portion (111-3) of the container (111) onto said additional element (218), compressing said annular seal (250).