HK1207921B - Battery with structured surface - Google Patents

Description

Battery with structured surface

Technical Field

The present invention relates to a primary or secondary battery comprising an anode casing, an anode located within the anode casing, a cathode casing joined to the anode casing, a seal sealing the cathode casing to the anode casing, a cathode located within the cathode casing between the anode and cathode casings and a membrane separating the anode and cathode.

Background

Shown in fig. 1 is an electrical energy storage cell, such as a button cell, known for powering electronic devices, such as watches or calculators. These button cells 1 comprise an anode casing 2, an anode 4 located within the anode casing, a cathode casing 3 joined to the anode casing 2, a seal 6 sealing the cathode casing to the anode casing, a cathode 5 located within the cathode casing between the anode and cathode casings, and a membrane 7 separating the anode and cathode.

To distinguish between the various types of button cells, the indicia 8 are made on one of the cell's exterior surfaces, i.e., on the cathode casing surface or on the anode casing surface.

These markings can be made in a variety of different ways. The first method involves the use of ink 8a or paint deposited on one surface of the cell. This method has the advantage of being simple and easy to adjust. In fact, it is easy to change the label for the first type of battery to the label for the second type of battery.

However, a first drawback of this solution is to ensure good adhesion of the layers to the battery casing. Another disadvantage is that the paint or ink on the battery can be easily wiped or scratched. In fact, none of these batteries are handled carefully and may fall or suffer from scratches or distorted appearance that can damage the ink or paint. If the deposited layer is damaged, ink or coating residue may leave the cell surface and contaminate the electrical contacts or interrupt the proper operation of the device.

Furthermore, the use of inks or paints also has the disadvantage of reducing the contact area of the battery, and therefore the marking must be formed in such a way that it does not prevent electrical contact from occurring. One solution consists in using more expensive conductive paints or inks, which still have the above-mentioned drawbacks and also limit the choice of colours to dark colours based on grey-black.

Another solution consists in forming the marks 8b and 8c by stamping. This method consists in plastically deforming the anode casing or more generally the cathode with the aid of a punch. The stamping may produce indicia 8b that will be visible from the other side of the housing, or indicia 8c may simply be created by crushing the material. However, this approach has the disadvantage of involving more complex management. In fact, each marking requires a different punch.

This therefore involves a complex battery manufacturing process, where the punch must be changed with each change of marking, or where a battery series with one or more specific markings is continuously manufactured.

Disclosure of Invention

The present invention relates to an electric energy storage cell, such as a cell battery, which overcomes the above-mentioned drawbacks of the prior art by proposing a battery capable of housing simple and durable markings which do not impair the electrical contact with the battery.

To this end, the invention relates to a battery or accumulator comprising an anode casing, an anode located inside the anode casing, a cathode casing fixed to the anode casing, a seal sealing the cathode casing to the anode casing, a cathode located inside the cathode casing between the anode and cathode casings and a membrane located between the anode and cathode, the anode casing and the cathode casing fixed to each other having a first outer surface and a second outer surface, respectively, the third outer surface being tangent to said first and second surfaces and serving as an edge of said accumulator, characterized in that one of the outer surfaces of said accumulator comprises at least one mark generated by the localized heating of the material, said mark being electrically conductive, said mark being a charge state monitoring device, said mark comprising a plurality of grooves forming a diffraction grating, when the surface of the grating is set deformed under the influence of the discharge of said accumulator or the charge/discharge of said accumulator, deforming the groove.

In a first advantageous embodiment, the local heating of said material forming the marking removes material.

In a second advantageous embodiment, the local heating of the material forming the marking is carried out by means of a laser.

In a third advantageous embodiment, the marking extends on at least any one of the surfaces of the accumulator.

In a fourth advantageous embodiment of the invention, the local heating of the material is carried out by means of a laser, so that the marking has a contrasting colour with the material of the surface to which it is applied.

In another advantageous embodiment of the invention, the local heating of the material is carried out by means of a laser, so that the marking has the same color as the material of the surface to which the marking is applied.

In another advantageous embodiment of the invention, the marking comprises a plurality of grooves forming a diffraction grating allowing to generate interference effects imparting a color to the marking.

In a further advantageous embodiment of the invention, the battery further comprises a second marking, which is a decorative image.

In a further advantageous embodiment of the invention, the battery further comprises a second marking, which is an anti-counterfeiting device.

In another advantageous embodiment of the invention, the anti-counterfeiting device comprises a combination of a plurality of recesses having different surface dimensions forming a unique arrangement.

In another embodiment of the invention, the anti-counterfeiting device comprises a combination of a plurality of recesses arranged parallel to each other, the spacing between two recesses and the width of the recesses being non-uniform to form a unique arrangement.

In another advantageous embodiment of the invention, the marking is a charge state monitoring device, said marking comprising a plurality of grooves forming a diffraction grating, said grooves being deformed when the surface on which the grating is provided is deformed under the influence of the charging or discharging of said accumulator.

In a further advantageous embodiment of the invention, the battery further comprises at least one electrically non-conductive marking.

The invention also relates to an electronic device comprising a closed casing containing an electronic module, said casing comprising a hatch closed by a hatch cover in which a battery for supplying power to the electronic module can be arranged, the battery being a battery according to any one of the preceding claims.

In an advantageous embodiment of the invention, the hatch is made of a transparent material to make visible the markings of the accumulator.

In an advantageous embodiment of the invention, the casing of the accumulator comprises a decoration and the marking of the accumulator is done so that the decoration and the marking combine to form an attractive assembly.

Drawings

Further advantages and features of the battery according to the invention will appear more clearly from reading the following detailed description of an embodiment of the invention, given purely by way of non-limiting example and illustrated by the accompanying drawings, in which:

fig. 1 is a schematic diagram of a battery according to the prior art.

Fig. 2 is a schematic cross-sectional view of a battery according to the present invention.

Fig. 3 and 4 are cross-sectional views of different labels of a battery according to the present invention.

Fig. 5 is a perspective view of a first application of a battery according to the present invention.

Fig. 6 is a view of the back cover of a watch case with indicia of a first application of the battery of the present invention.

Fig. 7 is a perspective view of a second application of the battery according to the present invention.

Fig. 8A and 8B are sectional views of a third application of the battery according to the present invention.

Detailed Description

Fig. 2 shows an electrical energy storage cell 10 as a cell according to the invention, which cell 10 may or may not be rechargeable. The cell 10 is, for example, a button cell and includes an anode casing 12 containing an anode 14. The cell also includes a cathode casing 13 secured to the anode casing 12. To ensure sealing between the anode casing 12 and the cathode casing 13, a seal 16 is used that seals the cathode casing 13 to the anode casing 12.

A cathode 15 is located within the cathode casing 13 between the anode 14 and the cathode casing 13. A membrane 17 is provided between the anode 14 and the cathode 15. The anode casing 12 has a first outer surface 21 and the cathode casing 13 has a second outer surface 22. For example, the first outer surface 21 and the second outer surface 22 are parallel to each other. The cell 10 also includes a third outer surface 23 tangent to the first and second surfaces 21, 22; the third surface 23 forms an edge of the cell 10 and is formed by a portion of the anode casing 12 and a portion of the cathode casing 13. However, the first outer surface 21 and the second outer surface 22 may not be parallel and may be curved.

The battery 10 is intended to be incorporated in an electronic device 100 such as a watch or a calculator. The electronic device 100 includes a housing 101 in which an electronic module is disposed. Such an electronic module is powered by the battery 10. The housing 101 is made such that: at its rear cover 102 has a hatch 103 in which the battery 10 is placed for electrical connection to the electronic module. This hatch 103 is closed by a battery hatch cover 104. Typically, when the battery 10 is disposed in its hatch 103, the surface becomes visible to the user. However, the electronic device 100 may allow several surfaces of the battery 10 to be visible. Electrical contact is made via the opposite surface of the user-visible surface, typically the second outer surface 21, i.e. the anode, and through a contact, typically in the form of a resilient metal strip, via a portion of the cathode casing which is the third outer surface 23 of the edge of the cell 10.

According to an advantage of the invention, the battery 10 has indicia 18. Such marking 18 is accomplished by local heating of the material. In a first embodiment, the localized heating of the material involves removing material from one of the surfaces of the cell 10. This removal of material is accomplished by laser engraving, i.e. directing a laser beam to the desired area. The material is then melted and evaporated by a laser. This use of laser engraving has the advantage of providing a simpler battery marking process, since only the programming of the laser is changed between one mark 18 and another. Furthermore, this method makes it possible to obtain engraving depths of 10 to 200nm, which are impossible to obtain by stamping. Laser engraving makes it possible to obtain a very good adhesion of the mark, since it is integrated in the material of the housing.

Preferably, the indicia 18 is fabricated such that it is electrically conductive. To achieve this, laser engraving is carried out in the ambient atmosphere in order to limit the conductivity drop (by oxidation between oxygen in the air and the material) to a value that does not affect the cell performance, i.e. is negligible for its internal resistance.

With the conductive label 18, the label 18 may extend over any surface of the battery. Such conductive indicia 18 may extend over the first outer surface 21, the second outer surface 22, or the third outer surface 23. Of course, the indicia 18 may extend over all surfaces simultaneously. This type of marking 18 has the advantage of having no restrictions on its arrangement or surface. In fact, since the marking 18 does not compromise the electrical contact, its shape is limited only by the available surface.

According to a characteristic of the invention, the marking 18 according to the invention can be colourless or coloured. This coloring or non-coloring depends on the parameters of the laser engraving process. These parameters are beam intensity, signal type (pulsed or continuous), pulse duration, air during engraving, etc.

The advantage of having the indicia 18 in black is that it provides a contrast between the material of the cell 10, i.e. the anode casing 12 and/or the cathode casing 13, and the indicia 18. This contrast means that the indicia 18 are prominent and noticeable.

Conversely, not colored means that the mark 18 has the same color as the base material as the case of the battery 10, so that it is hardly visible and thus can hide basic information that it does not need to be seen by the first eye.

In a second embodiment, the local heating of the material is carried out at a temperature that does not allow the material to be removed but simply colours the cell material. The coloring with different colors is achieved by selecting the parameters of the method, such as temperature, necessary to obtain the desired color. This technique, known as color change marking, can be implemented by a laser. In this way, the type of adjustment already used for ablation marking is also used, namely: beam width, beam type, beam frequency, marker air, etc.

In a modification as shown in fig. 3, the mark 18 may be generated to have a color different from black or the color of the bare cell material. To achieve this, the diffraction grating 180 is engraved using a laser engraving method. The diffraction grating 180 is formed of a plurality of grooves 180a parallel to each other.

These grooves 180a are defined by their shape and their size. The grooves 180a cause diffuse light reflection. An interference effect is generated during the specular reflection occurring at the tops of the non-faceted serrations 180b of the grating, which has a large number of small mirrors. This is thus the same physical configuration as the slot network. The width of the serrations 180b is equal to the opening of the slots and the grooves 180a are equal to the spacing between the slots. The spacing between the serrations may be varied from region to obtain a mosaic colour (like peacock feathers) as shown in figure 4. The boundaries between these regions will be black/disordered and thus the regions have some surface area within which the pitch needs to remain regular.

In a first application, these indicia 18 are used to form an attractive pattern 181 or decorative image as seen in fig. 5. For this purpose, when the battery 10 is located in its hatch 103, the attractive pattern(s) 181 are formed on the surface of the battery that the user sees. These attractive patterns 181 can be easily used to make limited quantities of plates.

Furthermore, the attractive pattern or patterns 181 may be integrated in a larger attractive assembly as seen in fig. 6. It is contemplated that there is a housing 101 with a decoration 105 for the device 100 and a component of the decoration 105 for the battery 10. To accomplish this, the indicia 18 of the battery 10 are designed to mate with the decoration 105 of the housing 101 and form an attractive assembly 106. For example, if the housing 101 has a decoration made up of stars forming a particular constellation (not shown), the indicia 18 of the battery 10 may take the form of an array of one or more stars, such that once the battery 10 is placed in the compartmentThe constellation is displayed in its entirety when in port 103. Also it may provide for example for creating and famous espionageThe related logo: the picture of the barrel is the decoration 105 of the housing 101 and the person's pattern forms the indicia 18.

On the other hand, attractive pattern 181 may simply be a manufacturer's logo or an indication of a characteristic of battery 10, such as the battery type or the voltage it provides. In this case, the mark 18 may be colourless so as to be less visible, especially when it is associated with another mark 18 as an attractive pattern 181. In such an application, the attractive pattern 181 may include a diffraction grating 180 to improve its appearance.

This first application is associated with an advantageous solution with a battery hatch 104 made of transparent material. This transparency allows the user to see the indicia 18 of the battery 10 when he wishes, and not just when replacing the battery 10.

In a second application, the marking(s) 18 are used for anti-counterfeiting purposes. Such security markings can take various forms.

The first form consists in generating a serial number. The serial number is preferably colorless, i.e., the same color as the bare material of the battery, so as to be more difficult to detect.

A second form of the authentication mark 18 is a specific configuration of a bar code 182 such as that shown in fig. 7. The bar code may be two-dimensional, i.e. engraved with a laser, and it is possible to envisage making a series of recesses 182a, which may be shallow or deep, wide or narrow and long or short and form, for example, a square. This particular combination is preferably made with a colorless mark to be as inconspicuous as possible. The bar code 182 may then be scanned to check the authenticity of the battery 10.

A conventional bar code formed of a plurality of parallel recesses 182a having the same depth but different widths and spacings may also be engraved.

In a variation of this second form of the security mark 18, each recess 182a may include a diffraction grating 180 to obtain a colored bar code 182. One advantage of marking and removing material by laser is that it is more reliable than printing because the bar code must be filed away to remove and thus leave a mark.

According to a third application, the markings 18 are used to form a charge indicator 183 of the battery 10. In fact, the battery profile varies depending on whether the battery 10 is fully charged or discharged. More specifically, when the battery 10 is fully discharged, the profile of the first outer surface 21 or the second outer surface 22 has a different appearance.

Skillfully, the charge indicator 183 of the battery 10 according to the present invention is composed of a diffraction grating 180 on the surface of the deformed battery 10. This diffraction grating 180 is formed of a plurality of grooves 180a parallel to each other. As explained above, such a grating decomposes light into different wavelengths whose propagation differs significantly from each other as shown in fig. 8A.

Thus, when the battery 10 is discharged, the surface, here the surface of the anode casing 12 on which the diffraction grating 180 is made, is deformed as seen in fig. 8B. This results in a change in the pitch of the diffraction grating 180. Thus, the light is disturbed differently and the color changes. This color change thus provides a visual indication of the state of charge.

It will be clear to a person skilled in the art that various alternatives and/or modifications and/or combinations of the different embodiments of the invention as set forth above may be made without departing from the scope of the invention as defined in the appended claims.

In a second variant, the battery 10 also comprises a marking made non-conductive. To achieve this, laser engraving is performed in oxygen atmosphere. This has the effect of oxidizing the engraved surface and reducing the conductivity sufficiently to disturb the current flow.

Claims (17)

1. An electric energy accumulator (10) comprising an anode casing (12), an anode (14) located within the anode casing, a cathode casing (13) fixed to the anode casing, a seal (16) sealing the cathode casing to the anode casing, a cathode (15) located within the cathode casing between the anode and cathode casings and a membrane (17) between the anode and cathode, the anode casing (12) and the cathode casing (13) fixed to each other having a first outer surface (21) and a second outer surface (22), respectively, a third outer surface (23) tangent to said first and second outer surfaces and serving as an edge of said accumulator, characterized in that one of the first outer surface (21), the second outer surface (22) and the third outer surface (23) of said accumulator comprises at least one marking (18) generated by localized heating of a material carried out by a laser, the mark is electrically conductive, the mark (18) is a state-of-charge monitoring device (183), the mark comprises a plurality of grooves (180a) forming a diffraction grating (180), which are deformed when one of a first outer surface (21), a second outer surface (22) and a third outer surface (23) provided with the diffraction grating is deformed under the influence of the discharge of the storage battery or the charge of the storage battery.

2. Accumulator according to claim 1, characterized in that the marking (18) is formed by removing said material.

3. Accumulator according to claim 1, characterized in that said marking (18) extends on at least any one of the external surfaces of said accumulator.

4. Accumulator according to claim 1, characterized in that said marking (18) extends on all the external surfaces of said accumulator.

5. Accumulator according to claim 1, characterized in that the local heating of the material is carried out by means of a laser so that the marking (18) has a contrasting colour with the surface material to which it is applied.

6. Accumulator according to claim 1, characterized in that the local heating of the material is carried out by laser, so that the marking has the same colour as the surface material to which it is applied.

7. Accumulator according to claim 1, characterized in that said marking (18) comprises a plurality of grooves (180a) forming a diffraction grating (180) generating a disturbing effect to impart a colour to said marking.

8. Accumulator according to claim 1, characterized in that said marking (18) is a decorative image.

9. Accumulator according to claim 1, characterized in that said marking (18) is an anti-counterfeiting device (182).

10. A battery according to claim 9, characterized in that the anti-counterfeiting device (182) comprises a combination of a plurality of recesses (182a) having different surface dimensions forming a unique arrangement.

11. Accumulator according to claim 9, characterized in that the anti-counterfeiting device (182) comprises a combination of several recesses (182a) arranged parallel to each other, the spacing between two recesses and the width of said recesses being non-uniform to form a unique arrangement.

12. The battery of claim 1, wherein the battery further comprises at least one nonconductive marker.

13. An electronic device (100) comprising a closed housing (101) containing an electronic module, said housing comprising a hatch (103) closed by a hatch cover (104) in which a battery for supplying power to the electronic module can be arranged, characterized in that said battery (10) is made in accordance with claim 1.

14. An electronic device (100) comprising a closed housing (101) containing an electronic module, said housing comprising a hatch (103) closed by a hatch cover (104) in which a battery for supplying power to the electronic module can be arranged, characterized in that said battery (10) is made in accordance with claim 8.

15. An electronic device (100) comprising a closed housing (101) containing an electronic module, said housing comprising a hatch (103) closed by a hatch cover (104) in which a battery for supplying power to the electronic module can be arranged, characterized in that said battery (10) is made in accordance with claim 9.

16. Electronic device according to claim 13, characterised in that the hatch (104) or any other element of the housing is made of a transparent material to allow the marking (18) of the accumulator to be seen.

17. An electronic device according to claim 13, characterized in that the casing of the accumulator comprises a decoration (105) and the label (18) of the battery is made such that the decoration (105) and the label (18) combine to form an attractive assembly (106).