Solid electrolyte battery

Abstract

To provide an improved battery.SOLUTION: The present invention provides a battery comprising: a cathode (3) which is continuously laminated onto a first surface (11) of a support body (1), and at least having a lower surface (32), an upper surface (33), and a side wall (31) directed to a lamination direction from the lower surface (32) to the upper surface (33) in the lamination direction; a solid electrolyte (4); an anode (5). In the battery, a coated part surrounding all of the side wall (31) of the cathode (3) without covering the upper surface (33) of the cathode (3) and contacted to them.SELECTED DRAWING: Figure 10

Description

Technical Field

[0001] The present invention relates to the field of electrochemical devices in the field of electrochemically storing energy. This is a solid-state electrolyte device that is small in size, i.e., smaller than 10 cm 2 and more preferably smaller than 1 cm 2 and is preferably of the micro-battery type.

[0002] The present invention has advantageous applications in manufacturing microelectronic devices. By microelectronic devices, this means any type of device made by microelectronic means. In addition, these devices particularly include optical or optoelectronic devices (such as MOEMS) in addition to purely electronic devices, microelectromechanical or electromechanical devices (such as MEMS, NEMS, etc.).

Background Art

[0003] A micro-battery is an electrochemical device composed of two electrodes (positive and negative, also called cathode and anode respectively) separated by an electrical insulator (electrolyte).

[0004] According to the current state of the art, a solid micro-battery is defined as a battery having the following characteristics: - All active layers (i.e., the positive electrode, electrolyte, and negative electrode) are made only of inorganic, solid-state materials, which typically means that there is no electrolyte made of polymer, liquid, or gel-like materials as in the case of standard batteries, nor is it an electrode material containing a polymer binder. - The individual thicknesses of all active layers (i.e., the positive electrode, electrolyte, and negative electrode) are less than 50 μm. In addition, the electrolyte thickness is usually less than 5 μm. In standard batteries, the thickness of each of these layers is usually greater than 100 μm. - The surface area of the micro-battery is approximately between 1 mm 2 and 10 cm 2 .

[0005] The miniaturization of mobile devices (connected objects, medical implants, etc.) requires small energy sources (especially a few millimeters) capable of storing a sufficient amount of energy. 2 This involves the ability to produce ) a battery. The capacity of a battery is directly proportional to the volume of the positive electrode, which is typically made from lithium cobalt oxide, often abbreviated as Lico or LCO, with the chemical formula LiCoO2.

[0006] As illustrated in Figure 1, in a conventional manufacturing of microbatteries, illustrating a typical microbattery stack, the stack is made by the continuous deposition of a first current collector 2, a first electrode 3, an electrolyte 4 (or ion conductor), a second electrode 5, and a second current collector 6 (which may take the form of a redistribution line) onto a support 1. Encapsulation is often necessary to protect the system from chemical reactions with oxygen and water vapor, either through the deposition of one or more additional protective layers 16 or by the transfer of a cap. The current collectors 2 and 6 each have contact reconnection portions that remain accessible through the outside of their stack for the electrical connection of the microbattery. Cavities 161 in the protective layer 16, corresponding to the second current collector 6, can reach the anode 5.

[0007] The movement of one or more ions between the two electrodes 3 and 5 through the electrolyte 4 allows for either energy storage or transport to an external circuit.

[0008] The current manufacturing of such structures is prone to defects, particularly when a significant cathode thickness is required, and this is often the case insofar as this thickness directly affects the battery capacity. However, significant surface roughness of the cathode has been observed, and more so than with greater thickness. For example, lithium has a very columnar structure with a granular surface.

[0009] Generally, and independently of the issue of cathode surface roughness, determining a significant cathode thickness induces manufacturing difficulties and structural disadvantages. [Overview of the Initiative] [Problems that the invention aims to solve]

[0010] The objective of the present invention is therefore to propose an improved battery and a method for manufacturing the same.

[0011] Other objects, features, and advantages of the present invention will become apparent upon consideration of the following description and accompanying drawings. It will be understood that other advantages can be incorporated. [Means for solving the problem]

[0012] To achieve this goal, according to one embodiment, a first surface of the support is continuously laminated, in the lamination direction, at least, - A cathode having a bottom surface, a top surface, and side walls oriented in the stacking direction from the bottom surface to the top surface, - One solid electrolyte, - A battery is provided, comprising one anode.

[0013] Advantageously, the battery has a covering portion that surrounds and contacts all of the side walls of the cathode, without covering the top surface of the cathode.

[0014] The cathode is embedded, or rather, surrounded, by the covering portion. This arrangement induces at least one of the following advantages:

[0015] The mechanical strength of the cathode can be increased by the lateral reinforcement it has through the covering portion, which can be useful during the manufacturing process, for example, if the upper surface of the cathode is machined, for example, by polishing, to improve its surface condition, and this reinforcement can also be useful after manufacturing to enhance the retention of the cathode to the support, especially when a significant cathode thickness is achieved.

[0016] Optionally, the coated portion can be obtained after removal, including mechanical action, of a portion of the coating layer covering the upper surface of the cathode, following the deposition of the coating layer covering the upper surface of the cathode.

[0017] Another potential area of interest for the coated portion is having a peripheral region of the upper surface of the cathode located at one and the same level, where the coated portion is at the same height as the upper surface and thus the deposition areas of other layers are present (in particular, but not limited to, the electrolyte and the anode), and this would apply when the cathode has undulations with respect to the area surrounding it, with fewer manufacturing constraints being imposed than for a recessed deposition surface that, possibly, at least a part of the upper surface of the coated portion is flat and continuous with the upper surface of the cathode, preferably oriented perpendicular to the stacking direction, and the surface of this assembly is particularly advantageous for the deposition of subsequent layers for making the battery.

[0018] Another aspect involves, in the stacking direction, on a first face of a substrate, at least - one cathode comprising a lower face, an upper face and side walls oriented in the stacking direction from the lower face to the upper face, - one electrolyte, - one anode, and includes the formation of a stack that continuously comprises these, and further includes the formation of a coated portion that surrounds and is in contact with all of the side walls of the cathode without covering the upper surface of the cathode, for manufacturing a battery.

[0019] Another aspect also relates to a system comprising a plurality of batteries. The batteries can be juxtaposed and / or superimposed.

[0020] Another aspect is a microelectronic device comprising at least one battery.

[0021] The objects, aims, as well as the features and advantages of the present invention will become most clearly apparent from the detailed description of one embodiment of the present invention, illustrated by the following accompanying drawings.

Brief Description of the Drawings

[0022] [Figure 1] Shows an example of a stack of electrochemical devices forming a solid electrolyte battery according to the prior art. [Figure 2] Has a series of steps for making a battery according to one embodiment. [Figure 3] Has a series of steps for making a battery according to one embodiment. [Figure 4] Has a series of steps for making a battery according to one embodiment. [Figure 5] Has a series of steps for making a battery according to one embodiment. [Figure 6] Has a series of steps for making a battery according to one embodiment. [Figure 7] Has a series of steps for making a battery according to one embodiment. [Figure 8] Has a series of steps for making a battery according to one embodiment. [Figure 9] Has a series of steps for making a battery according to one embodiment. [Figure 10] Has a series of steps for making a battery according to one embodiment. [Figure 11] Has a series of steps for making a battery according to one embodiment. [Figure 12] Has a series of steps for making a battery according to one embodiment. [Figure 13] Has a series of steps for making a battery according to one embodiment. [Figure 14] Has an example of a battery system with batteries stacked. [Figure 15] Has another continuation of the steps for making a battery. [Figure 16] Has another continuation of the steps for making a battery. [Figure 17] Has another continuation of the steps for making a battery. [Figure 18] Has another continuation of the steps for making a battery. [Figure 19] Has an example of a battery stack with batteries stacked. [Figure 20]An example of the formation of multiple batteries on a flat plate is illustrated. [Figure 21A] This provides an example of battery levels in a battery superimposed configuration. [Figure 21B] This provides an example of battery levels in a battery superimposed configuration. [Figure 21C] This provides an example of battery levels in a battery superimposed configuration. [Modes for carrying out the invention]

[0023] The drawings are provided as examples and do not limit the invention. They constitute schematic diagrams of principles intended to facilitate understanding of the invention and are not necessarily to the scale of practical applications. In particular, the thickness does not necessarily represent reality.

[0024] Before beginning a detailed examination of embodiments of the present invention, the following describes optional features that may be used in conjunction with or as alternatives to the present invention. - In one example, the upper surface 33 of the cathode 3 is flat, and the covering portion comprises an upper surface 71 having at least one flat portion continuous with the upper surface 33 of the cathode 3. - In one example, the covering portion comprises a main portion 72 made of a first material and a contact covering 73 made of a second material different from the first material, the contact covering 73 being in contact with the side wall 31 of the cathode 3 and provided between the main portion 72 and the side wall 31 of the cathode 3. - In one example, at least one electrical connection element 9 crosses through the covering portion and reaches the upper surface 71 of the covering portion. - For example, at least one electrical connection element 9 comprises at least one terminal 92 made from a conductive material, in particular from a soldering material, or a copper-based material that can be deposited by electrolysis, or also from a material that can be welded to its support, such as an aluminum terminal. - In one example, at least one electrical connection element 9 extends to a second surface 12 of the support 1, opposite to the first surface 11. - For example, a first current collector 2 connected to the cathode 3, a second current collector 6 connected to the anode 5, and at least one electrical connection element 9 comprises at least one first electrical connection element 9 connected to the first current collector 2 and at least one second electrical connection element 9 connected to the second current collector 6. - The present invention also relates to a system comprising a plurality of the above-described batteries. - At least two batteries are optionally superimposed. - At least one electrical connection element 9 of one of the batteries is electrically connected to at least one other electrical connection element 9 of the battery. - According to one possible embodiment of the above method, the formation of the covering portion is ○Formation of a covering layer that completely covers cathode 3, The thinning of the coating layer until the upper surface 33 of the cathode 3 is exposed includes thinning, which includes at least one polishing step. - The formation of the coating layer includes the formation of a coating layer 8 made of a first material on and in contact with the cathode 3, and then the formation of a main layer 7 made of a second material different from the first material on and in contact with the coating layer 8. - The first material is selected to have greater mechanical resistance to abrasion than the second material. - Polishing is applied to the main layer 7 by using the coating layer 8 as a polishing stop layer. - To expose the upper surface 33 of cathode 3, the process includes etching of the coating layer 8 after polishing. - Polishing is applied until the upper surface 33 of cathode 3 is exposed. - Optionally, the method includes forming at least one electrical connection element 9, and the polishing is configured to expose at least one electrical connection element 9 on the upper surface 33 of the coated portion. - Optionally, the method includes thinning of the support 1 by a second surface 12 of the support 1 opposite to the first surface 11, wherein the thinning is configured to expose at least one electrical connection element 9 on the second surface 12 of the support 1.

[0025] Within the scope of the present invention, it is explicitly stated that the terms “on” or “above” do not necessarily mean “in contact with.” Therefore, for example, the deposition of one layer on another does not necessarily mean that the two layers are in direct contact with each other, but rather that one layer at least partially covers the other, either by direct contact with the other or by separation from it by a film or similarly another layer or element. However, the layers of the first current collector, the first electrode, the electrolyte, the second electrode, and the second current collector are preferably laminated on a continuous contact surface. The layers do not necessarily cover the entire surface of the portion beneath them.

[0026] Furthermore, a layer can consist of several sublayers made from one identical material or from different materials.

[0027] A substrate, element, layer, etc., "based on" material M means a substrate, element, or layer containing only material M, or material M and optionally other materials, such as alloying elements, impurities, or doping elements. If necessary, material M can have various chemical amounts.

[0028] Within the scope of this invention, it is specified that the thickness of a layer or substrate is measured in a direction perpendicular to the surface on which the layer or substrate has its maximum elongation. Stacking of electrochemical devices is done in this direction. The transverse direction is oriented perpendicular to the thickness of the substrate.

[0029] A portion of the device of the present invention may have an electrical function. A portion may be used for conductivity, such as by electrodes, current collectors, or homogeneous materials, meaning an element formed from at least one material having sufficient conductivity in the application to achieve the desired function. Conversely, a portion may be used by an electrical or dielectric insulator, meaning a material that ensures electrical insulation in the application.

[0030] A battery, which means an element for storing and releasing electrical energy, comprises a stack of components, along with a cathode, a solid electrolyte, and an anode. For example, in this battery, the contact surface between the cathode and the electrolyte is 1 cm in projection in the stacking direction. 2 Furthermore, 20mm 2 Or even 10mm 2 If they are even smaller, they can be reduced in size to what are called micro batteries.

[0031] All battery assemblies can be made, whether or not they conform to the present invention, particularly by superimposing batteries in the stacking direction of their layers. A certain conductive element may serve to electrically connect at least one other battery in the assembly through a given battery.

[0032] Before providing details of embodiments, general notes relating to aspects of the present invention are given below, particularly by example.

[0033] The covering portion can be made from several sub-parts. For example, it may comprise a sub-part intended to be in direct contact with the cathode, also called a contact covering portion. This is not limiting, and it may be thinner than the rest of the covering portion. Preferably, this sub-part is derived from a deposition according to the material in order to form the contour of the cathode very uniformly. The covering portion may extend across a first surface of the support.

[0034] The covering portion may complement the main portion and extend laterally from the covering portion. This portion may be larger than the others and, in particular, may fill the entire area surrounding the cathode, extending to a height equal to the thickness of the cathode. This may be due to the formation of a "solid plate" of the covering layer extending to a thickness greater than the desired final thickness.

[0035] According to another possibility, the covering portion comprises three or more parts, for example, several layers formed continuously on the surface of the support and the cathode.

[0036] However, the coating portion can also be formed from a single step, particularly the formation of the coating layer, or from a single material.

[0037] Therefore, the coating layer from which the coating layer originates covers the entire cathode, even if the cathode is no longer exposed at all. However, this does not necessarily mean that all the layers initially formed to create the coating portion cover the entire surface of the cathode. In particular, the forming layer of the contact coating portion can be thin enough not to absorb the entire undulation of the upper surface of the cathode, and the cathode may have significant roughness at this manufacturing stage. At this stage, cathode material ridges may exist protruding from the coating layer. The coating layer can serve to reinforce this area and await subsequent polishing. Thus, the ridges will be gradually removed from above, with their bases not being destroyed.

[0038] Alternatively, the contact coating layer can cover the upper surface of the cathode so that the elements of the surface's undulations are not left exposed, and even in this case, the coating layer is a mechanical reinforcement that can be valued for polishing against the undulations it forms.

[0039] The electrical connection element 9 extends from the entire structure and is configured to conduct electricity between two points. The exemplified structure is merely an example. More generally, these elements may, in part, serve to electrically connect the cathode of at least one battery, preferably via a first current collector. In other parts, they are intended to electrically connect the anode of at least one battery, preferably via a second current collector. These elements preferably have main dimensions oriented in the stacking direction.

[0040] A sealing structure can also be advantageously formed to insulate one or more batteries from their environment. Preferably, a sealing frame is formed around the stack. This structure can be formed by assembling two sealing elements, one for the first battery and one for the second battery, with their surfaces facing each other.

[0041] Figures 2 to 13 illustrate a first example of a series of steps that enable the development of a battery according to the present invention.

[0042] Support 1 forms the starting element. It can be a flat plate made of a semiconducting material, particularly silicon. However, other substrates are possible, such as those made of glass. Furthermore, especially if the support comprises a base made of a conductive material, it can comprise a surface made of an electrical insulating material, typically silicon dioxide, for the silicon support base 1.

[0043] Support 1 will enable the production of multiple battery components in the stack. Unless otherwise addressed below in this description, the formation of these components can be carried out by layer deposition photolithography and etching steps to obtain the desired component patterns. Typically, physical vapor deposition (PVD) techniques can be used for layer deposition of the stack.

[0044] The first surface 11 of the support supports the first current collector 2. The current collector 2 is connected to its electrode, in this case the cathode 3, to establish conductivity between these two parts, and the current collector generally extends laterally beyond the cathode 3, out of the encapsulation device.

[0045] As an example, the first current collector 2 comprises at least one metallic layer, for example, titanium and / or platinum-based. In particular, it may comprise a platinum layer following an initial thin layer of titanium dioxide.

[0046] The stack then proceeds to the formation of cathode 3.

[0047] The material for the first electrode 3 can be LiCoO2 (as shown above). Furthermore, examples of materials that can similarly be used for the first electrode 3 are listed below: V2O5, TiS2, LiMn2O4, NaMnO2, NaCoO2. After the pattern of cathode 3 is formed, it generally undergoes annealing.

[0048] Preferably, the thickness of the cathode 3 is 10 μm or more, and more preferably 20 μm or more. Optionally, this thickness can be 70 μm or less. It will then be seen that such a significant thickness can be achieved by the present invention depending on the structure to be mounted and / or the preparation for manufacturing. In this step, it will be noted that the cathode 3 potentially represents a significant elevation above the first surface 11 of the substrate 1. It preferably comprises a side wall 31 extending in the direction of the stacking of the battery components (typically the dimension of the thickness of the support 1), a lower surface 32 in contact with the first current collector 2, and an upper surface 33 opposite the lower surface 32. The upper surface 33 is advantageously flat along a plane perpendicular to the stacking direction.

[0049] Typically, manufacturing would involve directly mounting the electrolyte onto cathode 3. However, as illustrated in Figure 3, it is proposed to pre-form the covering portion of cathode 3.

[0050] To achieve this, in the embodiment shown in Figure 3, it is initiated by forming a contact coating layer 8 configured to completely cover the cathode 3. However, it should be noted that the formation of layer 8 is not essential. In fact, the coating portion can be made without resorting to this step.

[0051] Layer 8 has a side portion 81 that covers the side wall 31 of the cathode 3, an upper portion 82 that covers the upper surface 33 of the cathode 3, and a base portion 83 that is provided on the surface 11 of the support.

[0052] However, as shown above, roughness, particularly the undulations of the upper surface 33, may remain protruding beyond the contact coating layer 8. Preferably, the coating layer 8 also covers the rest of the support surface 11. This layer may be mineral, for example, made from TEOS (tetraethyl orthosilicate), SiN, or SiON, or it may be organic (for example, a polymer such as parylene, whether photosensitive or not). The contact coating layer 8 may be formed from several sublayers of different materials, for example, according to the examples given above. The thickness of the coating layer 8 may be 200 nanometers or more and / or 10 μm or less.

[0053] The first potential interest of the coating layer 8 is to act as a stop layer during subsequent thinning steps, including polishing, as detailed below. Alternatively, or complementaryly, this layer 8 can have a protective role in preventing particle detachment from the cathode 3 material, typically Lico.

[0054] As shown above, the material of cathode 3 may have irregularities in the form of pointed shapes on its exposed surface, especially when the cathode is thick. According to one non-limiting aspect of the present invention, layer 8 plays a role in maintaining the pointed shapes during the thinning of the main coating layer 7. In particular, the thickness of layer 8 can be less than the maximum height of the pointed shapes, and can be, for example, between 30% and 75% of the maximum height of the pointed shapes. In this case, these pointed shapes protrude beyond layer 8 and are then covered by layer 7. They are held laterally by layer 8 during the thinning of layer 7, which also leads to wear of the ends protruding from the pointed shapes, without detaching them at their bases. Even if the bases of the pointed shapes are present, the undulation of cathode 3 is clearly reduced therefrom.

[0055] According to one possibility, at least several steps are carried out to create electrical connection elements 9 in parallel with the formation of the battery stack. This is reflected in Figure 4, where one or more cavities 13 are created in the support 1 by intersecting through the coating layer 8, for example, in the form of trenches. Etching steps or saw cuts can also be implemented for this purpose. Preferably, this formation is configured to expose a portion of the first current collector 2 laterally to the layer 8 to make it accessible.

[0056] Figure 5 has the following steps: a conductive portion is created in the cavity 13 in the form of a wall portion 91, which can be derived from a metal coating. A titanium and gold bilayer can be used, for example. The portion 91 can cover the entire surface of the cavity 13. Due to at least some electrical connection elements 9, the portion 91 can be in contact with the first current collector 2 for the electrical connection of the cathode 3. As shown above, other electrical connection elements 9 can have a function for the electrical connection of other, in particular, the anode 5. In the representation of Figure 5, the portion 91 illustrated to the right of the cathode acts as a connection to the first current collector 2, and the portion 91 illustrated to the left of the cathode is not connected to the first current collector 2 but can act as a connection to the anode 5 via the second current collector 6. Furthermore, especially when the support 1 is conductive, an electrical insulating layer can also be deposited before forming the portion 91, and this insulating layer can be etched to establish electrical contact of the portion 91 with the current collector 2.

[0057] The formation of the electrical connection elements 9 can be followed by creating terminals 92 made of a conductive material in contact with a portion 91 for each element 9, particularly to at least partially fill the cavity 13, and preferably to form an element that protrudes beyond it.

[0058] For terminal 92, a lead and / or tin-based material can typically be used, according to a technique known as "bumps." This solution is relatively inexpensive. Also, terminal 92 can be made from gold or aluminum, especially if such bumps have a "stud bump" shape.

[0059] To increase the height of the conductive element 9, the manufacturing process advantageously includes an additional step, as illustrated in Figure 7, of forming at least one second terminal 93 that is conductive and above the terminal 92. It is understood that the resulting structure projects laterally beyond the first surface 11 of the support 1 toward the stack comprising the cathode 3. Preferably, the height of this structure is equal to or greater than the height of the upper surface 33 of the cathode 3 in this step, and preferably strictly greater.

[0060] Figure 8 illustrates the formation of the main covering layer 7, which covers all elements already formed on the first surface 11 of the support 1.

[0061] According to one possibility, layer 7 can be obtained by molding, for example, by planarizing a mold for the device and by injecting a polymer material at a sufficient temperature. Layering can also be used by layering a film on top of the coating layer 8 and by continuing the creep of the layered material by increasing temperature. Thus, it is understood that the cathode 3 is completely insulated from the outside by the coating formed from the coating layer 8 and the main layer 7 in the illustrated example.

[0062] Based on this, the thinning of the coating is continued until the configuration shown in Figure 9 is obtained. In this figure, the upper surface 33 of the cathode 3 is exposed, but the rest of its wall remains protected by the coating portions 72 and 73 formed by the contact coating layer 8 and the rest of the main coating layer 7.

[0063] To achieve such a configuration, thinning involves polishing. This can be a purely mechanical action, such as grinding or dry polishing, or a mechanical and chemical action, such as chemical mechanical polishing, which simultaneously implements mechanical and chemical etching with a solution adapted to at least one etching of the coating material.

[0064] According to one possibility, polishing is performed to thin the main coating layer 7 by using the upper part of the contact coating layer 8 as a stopping layer. In this configuration, polishing can be successfully completed by precisely stopping on the coating 8.

[0065] Optionally, the coating 8 can be thinned at a lower speed during polishing to gradually reduce the roughness of the upper surface 33 of the cathode 3. Preferably, in this context, the material chosen for layer 8 is more mechanically resistant to polishing (in particular, harder) than the material chosen for layer 7.

[0066] According to the first possibility, polishing ensures the exposure of the surface 33 of cathode 3, either by its mechanical action on the coating aggregate or by its mechanical action which is completed by a chemical action targeting the coating layer 8.

[0067] According to another possibility, polishing is stopped before surface 33 is exposed. The top of layer 8 is then removed by etching, which can be dry etching or wet etching.

[0068] The resulting configuration can be seen in Figure 9, which shows that the cathode 3 is maintained laterally by the covering portion comprising a contact coating 73 from the contact coating layer 8 and a main coating portion 72 from the main coating layer 7.

[0069] If the steps described above are implemented to thin the coating, a flat top surface 71 is obtained for the coating portion. Furthermore, the top surface 71 is at the same height as the top surface 33 of the cathode 3. The example illustrates some lateral extension of the coating portions 72, 73, but this can be further restricted. However, it covers the entire height of the cathode 3 laterally from the cathode for at least a certain distance.

[0070] Furthermore, Figure 9 illustrates that the pre-formed electrical connection element portion 9, particularly the terminal 93, is exposed by thinning. Thus, the element 9 is also advantageously embedded in the covering portions 72 and 73, and their exposure is achieved without any additional steps.

[0071] Therefore, the creation of the battery stack continues. In Figure 10, the electrolyte 4, anode 5, protective layer 16, and second current collector 6 are formed in succession from the upper surface 33 of the cathode 3 and the upper surface 71 of the covering portion. Manufacturing is simplified as long as the flat surface is advantageous for these additional operations, and the cathode 3 no longer has any undulations with respect to the first surface 11 of the support 1, which is a terrain that is generally disadvantageous for layer deposition implementation.

[0072] Electrolyte 4 is advantageously made from a solid ion conductor, which can be LiPON.

[0073] In a configuration where the surface and environment of cathode 3 form a flat area, anode 5 can be wider than in the standard configuration, and in particular wider than cathode 3, which can be advantageous from the viewpoint of electrostatic control. Anode 5 can be made of, for example, a metallic conductor, particularly titanium. The second current collector covering it can be made preferably from copper, or titanium, or any other conductive material, preferably metal. As shown above, the opening 161 in the protective layer 16 can allow electrical connection of anode 5 while maintaining the stack protected by the protective layer 16. The protective layer can be made of, for example, polyparaxylylene.

[0074] For the connection of the anode 5, the formation of the second current collector 6 can be configured to connect it to at least one electrical connection element 9, typically shown on the left in Figure 10. The electrical connection can be completed by a contact reconnection element 94, made of, for example, gold.

[0075] Furthermore, a sealing element can also be generated, which will serve to insulate the battery from the external environment. In the embodiment presented in Figure 10, it is advantageous to create a sealing seam 10a from the formation of certain elements, particularly from the second current collector 6 and the contact 94. The sealing seam is not visible in Figure 10 as a cross-sectional view, but is advantageously configured to form a closed contour around the battery. An example of a contour for a battery 17i is given in Figure 21A.

[0076] A battery formed in this manner can conventionally be electrically connected to operate it. The reconnection of the electrical contacts on the front, as shown in Figure 10, makes this possible.

[0077] The subsequent steps can optionally perform contact reconnection using the rear surface of support 1 and the second surface 12.

[0078] Therefore, in Figure 11, the front surface is encapsulated in an encapsulation layer 18 (for example, made of polymer) with a battery stack, and the second surface 12 of the support is thinned to expose the electrical connection elements 9 through the bottom of the cavity 13.

[0079] The following steps in Figure 12 involve metal deposition, for example, by a titanium and gold bilayer, which allows for the creation of a contact reconnection element 95 on the rear surface of the electrical connection element 9. As described above, this formation can be used to create another sealing seam 10b, as is proposed for the sealing seam 10a on the other surface. Of course, the specific embodiments proposed for sealing are not limiting, and it can benefit from metal layer deposition and patterning steps performed for other purposes. Sealing can be reliably achieved by different steps.

[0080] In general, according to the present invention, an electrical insulating layer can be mounted at the interface between the support 1 and all or part of the conductive members of the present device, particularly when the support 1 is conductive.

[0081] Optionally, a recess 14 can be created in the support in a region facing the battery stack containing the cathode 3. Etching can be implemented for this purpose. This arrangement determines a volume that can be useful for stacking batteries, as shown in Figure 14.

[0082] In fact, the recess 14 is configured to at least partially accommodate the superimposed battery. The interest of this arrangement is that it can accommodate the swelling of the battery during charging.

[0083] In the configuration shown in Figure 14, three levels of batteries a, b, and c are superimposed. This number is, however, merely an example. Preferably, the lower level, level c, has a battery stack encapsulated in layer 18. On its opposite side, this battery accepts the battery of level b. An electrical connection is created between these two levels via an electrical connection element 9. The implementation illustrated here forms a parallel circuit, with the positive terminals of the batteries connected to a common node formed by the continuity of one electrical connection element 9, typically shown on the right in Figure 14. Similarly, the anodes of the batteries are connected by another electrical connection element 9, which is shown on the left in Figure 14.

[0084] An equivalent connection is made between levels b and a. The last level opposite to the one presented at the bottom of the battery stack can here serve as the external connection to the battery via the exposed portion of the connecting element 9 it possesses.

[0085] Afterward, it will become clear that other electrical connection diagrams are possible.

[0086] On the other hand, the sealing seams 10a and 10b create a peripheral assembly for the battery, and the seams create an internal volume in which the battery stack is located.

[0087] The assemblies between the levels, whether they are sealing seams 10a, 10b and / or electrical connection elements 9, can be made by direct bonding, soldering, or thermal compression. The advantages of having a gold / gold interface will be noted in this context through the resulting contact quality and cold glue capacity.

[0088] Preferably, the battery assembly is manufactured under vacuum or under a flow of a neutral gas such as argon.

[0089] In the integration described above, a portion of the substrate, such as silicon, is retained, which is advantageous for mechanical strength, especially when a metal seal (particularly gold / gold) is implemented. Nevertheless, stress and mechanical strength depend largely on the surface of the battery. In some cases, it is possible to completely remove the support 1 as an alternative to the above case and modify the structure to have an expanded battery stack volume.

[0090] Figures 15 to 19 illustrate this possibility, with Figure 19 showing a modified battery stack configuration.

[0091] Figure 15 illustrates a structure that is quite similar to that obtained in Figure 10. To achieve this, all common parts can be referenced to the description of the previous embodiment.

[0092] Clearly, the front contact reconnection is preferably located on the side of the battery stack, as shown in Figure 15, to connect the battery stack to other superimposed batteries. Therefore, in this optional configuration, the electrical connection elements 9 do not necessarily cross through the support in the cavity 13. They can be made on the first surface 11 of the support 1. In the example shown in Figure 15, as described above, they have one or more terminals that cross through the thickness of the covering portion, here in portion 72.

[0093] Furthermore, as mentioned above, Figure 15 illustrates a covering portion having two consecutive parts 72, 73, but it should be noted that this embodiment is not limiting. It may be possible to implement it with a single part, or with three or more parts.

[0094] The steps in Figure 16 allow for the creation of a volume remaining around the stack containing the electrolyte and anode. For this purpose, a sealing frame 19 is formed around the battery stack and on the surface 71 of the covering portion. The sealing frame has dimensions that are greater in thickness than that of the battery stack, typically so that space exists above the stack, particularly above the second current collector 6.

[0095] The sealed frame 19 can be made by forming an outer wall 191 and an inner wall 192, the gap between them then filled with a filler material 193. More specifically, lithography and layering steps can be used to make the walls 191 and 192. The filler material 193 can be deposited by screen printing of solder paste or by electrolysis.

[0096] For walls, a SiNR-type photosensitive dielectric polymer material, sold under the trademark Shin-Etsu®, can be used in the form of a dry film or by spin coating.

[0097] As mentioned above, however, it is advantageous to proceed with the electrical connection structure stage simultaneously with the sealing structure, but not limited to that.

[0098] This is also proposed in Figure 16. Thus, a connecting trench 152 is defined using an additional wall 151 provided inside the inner wall 192 relative to the battery stack. Wall 151 can be made simultaneously with walls 191 and 192. It is also possible to fill the trench 152 thus defined between walls 151 and 192. Solder paste can also be used. In this case, contrary to the filling 193, it is preferable to form a discontinuous filling that is not completely filled in the trench 152, but is basically in contact with element 9. The current collectors can be electrically connected via electrical connection elements according to different configurations. In particular, as shown in Figures 16 to 19, the trench 152 can play a role in generating element 9 in contact with the second current collector 6 downstream of the wall 151 which rests on at least a portion of the second current collector 6 thus extended toward element 9 in the trench 152. However, other situations can be considered, such as retaining a portion of the surface without the wall 151, so that the second current collector 6 is not interrupted.

[0099] Figure 17 has steps similar to those in Figure 11, by creating an encapsulation 18 for a first example of a battery configuration for the battery assemblies to be superimposed. This example can constitute an edge level of superposition.

[0100] In this embodiment, the original support 1 is completely removed as shown in Figure 18. Thus, on the rear side, the support is gone and the electrical connection element 9 is accessible for electrical connection. As described above, this can be achieved by forming the contact reconnection element 95, for example in the form of a metal coating, which may include a gold surface layer and, for example, a titanium / gold bilayer.

[0101] Furthermore, as mentioned above, the metal coating step can be utilized to form the contacts 95 that make up the sealing seam 10b, and it is conceivable that such seams can be made separately.

[0102] Based on the structure in Figure 18, other batteries can be superimposed, as illustrated in Figure 19, which shows three levels. In this case, the spacer function of the sealed frame 19 is to maintain the internal volume of the battery stack housing.

[0103] The sealing can be made in the same way as in the previous case, especially at the gold / gold adhesive interface. Similarly, the electrical connection elements 9 can be connected sequentially level by level according to the desired electrical configuration.

[0104] In this regard, Figure 20 illustrates different possibilities.

[0105] In one embodiment, it illustrates the ability to have multiple batteries 17i, 17j, 17k on one same level of the battery matrix 12. In particular, in this case, the batteries may share one same support or one same covering portion 72, 73, at least during manufacturing. They may or may not be individualized.

[0106] In another embodiment, this figure reflects the fact that the electrical connection elements 9 can be made in common. For example, one identical trench, diagrammed here by a dotted line, can be formed to create several juxtaposed battery cavities 13 or trenches 152. Conductive elements 9 are then individually made within these trenches.

[0107] It is understood that the battery proposed here allows for juxtaposition configuration, as shown in Figure 20, or superimposed configuration, as shown in Figures 14 and 19.

[0108] Multiple configuration possibilities are also evident from Figures 21A and 21C. Figure 21A illustrates a battery at level a, considering its superposition with two other levels, b and c. This level comprises multiple conductive elements 9.

[0109] When series and / or parallel connections are made between superimposed batteries, only two conductive elements 9 from the batteries are needed (one for the anode and one for the cathode).

[0110] However, the individual addressing of the superimposed batteries can also be continued, so as to connect them individually to the outside. To achieve this, each continuum of superimposed batteries has at least twice as many conductive elements 9 as the level. In the represented case, for example, battery 17i has six electrical connection elements (i.e., enough to electrically connect the two electrodes of each battery on three levels).

[0111] In this context, the two first electrical connection elements 9 will serve as electrical connections to the battery 17i at this level, which is illustrated in Figure 21A by the gray fills of the two corresponding elements 9. The four other elements 9 of batteries 17i, 17j, and 17k will serve as conduits to the batteries at the other levels.

[0112] Therefore, Figure 21B illustrates the level of battery b, and the two connection elements 9, which are continuous with the two electrical connection elements 9 of level a and are diagrammed as gray fills, play a role in electrically connecting the cathode 3 and anode 5 of batteries 17i, 17j, and 17k of level b.

[0113] Finally, the level c batteries have two connecting elements 9 for connecting their cathodes and their anodes. These elements are continuous with the lower level elements 9.

[0114] Therefore, batteries of different levels can be individually connected through electrical connections that pass through the structure, which are formed by the superposition of the connecting elements 9.

[0115] In the solutions shown in Figures 21A to 21C, all batteries in the battery system are independent. Without departing from the scope of the present invention, all or some of the batteries in one level may be further connected in series or in parallel, and each level may be electrically connected independently.

[0116] The present invention is not limited to the embodiments described above, but extends to all embodiments encompassed by the present invention. [Explanation of Symbols]

[0117] 1 Support 2. First current collector 3 Cathode 4 Electrolytes 5 Anodes 6. Second current collector 7 Main coating layer 8 Contact coating layer 9. Electrical connection elements 10a Sealed Seam 10b Sealed seam 11 First side 12. Second side 13 Cavity 14 recess 16 Protective layer 17i, 17j, 17k batteries 18 Encapsulation layer 19. Sealed frame 31 Side wall 32 Bottom side 33 Top surface 71 Top surface 72 Main covering part 73 Contact coating 81 Side 82 Top 83 Base 91 Wall section 92 terminals 93 Second terminal 94 Contact reconnection element 95 Contact reconnection element 151 Wall 152 Connecting Trench 161 Aperture 191 Exterior Wall 192 Inner wall 193 Filling materials

Claims

1. The laminated films are laminated continuously on the first surface (11) of the support (1), and in the lamination direction, at least a cathode (3) having a lower surface (32), an upper surface (33), and a sidewall (31) extending from the lower surface (32) to the upper surface (33) in the stacking direction; A solid electrolyte (4), an anode (5), a covering portion surrounding and in contact with all of the side walls (31) of the cathode (3) without covering the top surface (33) of the cathode (3), the covering portion having an upper surface (71); at least one electrical connection element (9) that crosses through the covering portion and leads to the top surface (71) of the covering portion and to a second surface (12) of the support (1) opposite the first surface (11); A battery comprising:

2. 2. The battery of claim 1, wherein the upper surface (33) of the cathode (3) is flat, and the upper surface (71) of the covering portion has at least one flat portion continuous with the upper surface (33) of the cathode (3).

3. 3. The battery of claim 1, wherein the covering portion comprises a main portion (72) made of a first material and a contact covering (73) made of a second material different from the first material, the contact covering (73) being in contact with the side wall (31) of the cathode (3) and being provided between the main portion (72) and the side wall (31) of the cathode (3).

4. 3. The battery according to claim 1 or 2, wherein said at least one electrical connection element (9) comprises at least one terminal (92) made from an electrically conductive material.

5. 2. The battery according to claim 1, comprising a first current collector (2) in electrical communication with the cathode (3) and a second current collector (6) in electrical communication with the anode (5), and wherein the at least one electrical connection element (9) comprises at least one first electrical connection element (9) connected to the first current collector (2) and at least one second electrical connection element (9) connected to the second current collector (6).

6. A system comprising a plurality of batteries according to claim 1.

7. A system as described in claim 6, comprising a plurality of batteries as described in claim 5, and at least two batteries being superimposed.

8. 8. The system of claim 7, wherein at least one electrical connection element (9) of one of the batteries is in electrical communication with at least one other electrical connection element (9) of the batteries.

9. On the first surface of the substrate (1), at least a cathode (3) having a lower surface (32), an upper surface (33), and a sidewall (31) extending from the lower surface (32) to the upper surface (33) in the stacking direction; an electrolyte (4); 1. A method for manufacturing a battery comprising forming a stack comprising, in succession, a cathode and an anode (5), Formation of a coating surrounding and in contact with all of the side walls (31) of the cathode (3) without covering the top surface (33) of the cathode (3), i. forming a coating layer that completely covers the cathode (3); ii. forming the coating part, including thinning the coating layer until the top surface (33) of the cathode (3) is exposed, the thinning including at least one polishing step; Formation of at least one electrical connection element (9); thinning of said support (1) by a second surface (12) of said support (1) opposite said first surface (11); The method, wherein the polishing is configured to expose the at least one electrical connection element (9) on the top surface (33) of the covered portion, and the thinning of the support (1) is configured to expose the at least one electrical connection element (9) on the second surface (12) of the support (1).

10. 10. The method of claim 9, wherein the formation of a coating layer comprises the formation of a coating layer (8) made of a first material on and in contact with the cathode (3), followed by the formation of a main layer (7) made of a second material different from the first material on and in contact with the coating layer (8).

11. The method of claim 10 , wherein the first material is selected to be more mechanically resistant to abrasion than the second material.

12. 12. The method according to claim 10 or 11, wherein polishing is applied to the main layer (7) by using the cover layer (8) as a polishing stop layer.

13. 13. The method of claim 12, comprising, after polishing, etching the covering layer (8) to expose the top surface (33) of the cathode (3).

14. 12. The method according to any one of claims 9 to 11, wherein polishing is applied until the top surface (33) of the cathode (3) is exposed.

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