JP2008293793A - Solid thin film battery, and manufacturing method of solid thin film battery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a solid thin film battery in which quality is stabilized and its yield is improved by preventing breakage of a membrane of a solid electrolyte layer, and deterioration of battery performance can be prevented even in the case bending or the like is applied, and which has a high flexibility. <P>SOLUTION: This is the solid thin-film battery 1 which has a positive electrode layer 4, a negative electrode layer 6, a solid electrolyte layer 7 arranged between these layers, and a support body 2 on which these respective layers are laminated and supported, and is provided with chamfer parts 7, 7 at the side edge parts of the positive electrode layer or/and the negative electrode layer. By adopting this structure, breakage of a membrane of the solid electrolyte layer is prevented, and the solid thin-film battery with stable quality and high flexibility can be provided. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a solid-state thin-film battery, and more particularly to a solid-state thin-film battery that can exhibit stable performance, has a good yield, and does not deteriorate battery performance even when bent.

  The configuration of the solid thin film battery is, for example, a laminated structure in which a positive electrode layer, a solid electrolyte layer, and a negative electrode layer are sequentially stacked on a metal foil that is a current collector or a metal film formed on a ceramic substrate such as alumina. ing. When a solid electrolyte layer is used, an organic electrolyte solution is not used unlike a conventional battery, so that there is no risk of liquid leakage or ignition, and a highly safe battery can be provided.

  In recent years, portable electronic devices such as mobile phones have been increasingly reduced in size and weight, and batteries mounted thereon are also required to be reduced in size and weight. In addition, as a result of multifunctionalization, a battery having a higher voltage and a larger electric capacity is demanded, and a battery capable of exhibiting stable performance is demanded.

JP 05-50617 Patent No. 3116857

  For example, in a solid-state thin film battery having a laminated structure as described in Patent Document 1, these electrodes are connected so as to connect a positive electrode layer and a negative electrode layer that are spaced apart in the surface direction of the support. The solid electrolyte layer is laminated and formed between the layers.

  Since the positive electrode layer and the negative electrode layer are laminated on the support with a predetermined thickness, a step is formed between the electrode layer and the support, and the solid electrolyte layer also corresponds to the step. In this manner, the electrode layer and the support are laminated and formed.

  However, since each of the electrode layers has a substantially rectangular cross section, when the thickness of the solid electrolyte layer is smaller than the thickness of the electrode layer, the solid electrolyte layer is continuously laminated on the stepped portion. In many cases, the solid electrolyte layer becomes discontinuous. If the solid electrolyte layer breaks, there arises a problem that the battery performance is lowered and the yield of the product is also lowered.

  Further, when the thin film battery is bent, there is a high possibility that stress or deformation concentrates in the vicinity of the stepped portion and a crack or the like occurs in the solid electrolyte layer. Further, even between the positive electrode layer and the negative electrode layer and the support on which these layers are laminated, stress and deformation are concentrated in the vicinity of the edge portions of these laminated surfaces due to bending, and a peeling phenomenon is likely to occur between these layers. .

  The invention of the present application provides a highly flexible solid thin film battery capable of stabilizing the quality and improving the yield by preventing film breakage of the solid electrolyte layer, and preventing deterioration of the battery performance even when bent or the like. This is a problem.

  The present invention is a solid thin film battery comprising a positive electrode layer, a negative electrode layer, a solid electrolyte layer disposed between these layers, and a support on which these layers are laminated and held, wherein the positive electrode layer and / or the negative electrode A chamfer is provided on the side edge of the layer.

  By providing the chamfered portion, the thicknesses of the edge portions of the positive electrode layer and the negative electrode layer are reduced, and stress and deformation can be reduced from being concentrated on the edge portions of the electrode layers when bent. For this reason, it becomes difficult to peel the said electrode layer and a support body, and joining strength increases.

  In addition, by providing the chamfered portion, the stepped form between the positive electrode layer or / and the negative electrode layer and the surface of the support on which these electrode layers are laminated is eased. For this reason, when the solid electrolyte layer is formed in a spanning manner between the electrode layer and another region having a step in the thickness direction via the chamfered portion as in the invention described in claim 2 Thus, the solid electrolyte layer can be surely laminated in the vicinity of the stepped portion. Therefore, the film breakage of the solid electrolyte layer can be prevented. Further, since stress and deformation concentration in the vicinity of the stepped portion can be relaxed, it is possible to prevent the electrolyte layer from being cracked when the battery is bent.

  The present invention can be applied to a solid-state thin film battery made of various materials. For example, as the positive electrode layer, a thin film layer using an active material such as lithium manganate (LiMnO 2), lithium cobalt oxide (LiCO 2 O 2), manganese oxide (MnO 2), iron sulfide (FeS 2) alone or in a mixture can be employed. Moreover, it can comprise by providing the coating layer by the screen printing method etc. which contain the carbon particle of a conductive support agent, a binder, etc. in the powder of the said material.

  On the other hand, as the negative electrode layer, for example, an alloy film such as a Li metal film, Li—Al, Li—Mn—Al, Si, Si—N, Si—Co, or Si—Fe can be employed. In addition, a coating layer made of powder of carbon, Si or the like, carbon particles of a conductive additive, and a binder may be employed.

  As the solid electrolyte disposed between the positive electrode layer and the negative electrode layer, for example, an amorphous film made of Li—P—S—O or a polycrystalline film thereof can be used. Further, an amorphous film made of Li—P—S—N or a polycrystalline film thereof can be employed. In particular, it is preferable to employ an amorphous film made of the above Li—PS—O as the positive electrode side electrolyte and an amorphous film made of the above Li—P—S—N as the negative electrode side electrolyte.

The electrode or the solid electrolyte can be impregnated with an ion conductive material to increase conductivity. For example, as the ion conductive material, (1) cationic materials such as EMI ⁺ , PyI 3 ⁺ and PPI 3 ⁺ , (2) anionic materials such as FSI ⁻ and TFSI ⁻ , (3) support such as LiTFSI and LiBETI It can also be impregnated with salt.

  By impregnating the ionic conductive material in the voids of the positive electrode layer and the solid electrolyte layer and increasing the ionic conductivity between the positive electrode layer and the solid electrolyte layer, the electric resistance at the interface between the positive electrode layer and the solid electrolyte layer is reduced. The battery capacity on the positive electrode side can be increased.

  Various materials can be employed as the support in the present invention. For example, the electrode layer can be laminated on a metal thin film support that also serves as a current collector, directly or via an electrically insulating film. Further, the electrode layer can be formed directly or via a current collector on an electrically insulating film-like support.

  When the positive electrode side current collector is used as the support, a metal foil such as Al, Ni, and stainless steel can be employed. On the other hand, a metal foil such as Cu, Ni, and stainless steel can be adopted as the negative electrode side current collector.

  Moreover, various insulating films can also be employed as the support. For example, a general flexible printed wiring board can be used as the support.

  The form and dimensions of the chamfered portion are not particularly limited, and can be set according to the thickness of the positive electrode layer, the negative electrode layer, and the electrolyte layer, the required deformation amount, and the like. For example, as in the invention described in claim 3, the chamfered portion in which the positive electrode layer and / or the negative electrode layer have a substantially trapezoidal cross section can be provided.

  Moreover, it is not limited to the chamfering form which cut | disconnected the cross-sectional corner | angular part of the electrode layer in the plane, and can also provide a curved chamfering part, such as a circular arc cross section.

  According to a fourth aspect of the present invention, the positive electrode layer and / or the negative electrode layer includes a linear portion having a predetermined width, and at least the chamfered portion is provided on a longitudinal side edge of the linear portion. is there.

  For example, in order to adjust the capacity or the like of the electrode, one or both electrodes are formed on the support in a comb-like shape having a linear portion with a predetermined width, and a solid electrolyte layer is formed between the support surface and the like. In some cases, the layers are stacked in a hanging manner. In such a case, the stepped part of each electrode layer and the support becomes very long corresponding to the dimension in the longitudinal direction, and if the film breaks at this part, the battery performance is greatly affected. The film breakage can be prevented by providing the chamfered portion at least at the longitudinal edge of the linear portion.

  In addition, the step-down form of the solid electrolyte layer is relaxed, and a solid electrolyte layer having a uniform thickness can be formed on the stepped portion. Therefore, when the battery is bent or the like, it is possible to prevent stress and deformation from being concentrated on the stepped portion and causing a crack or the like in the solid electrolyte layer. Furthermore, each electrode layer provided with a chamfered portion is also difficult to peel off from the surface of the support, so that it is possible to prevent deterioration in performance when bent or the like.

  The lamination form of the positive electrode layer, the negative electrode layer, and the solid electrolyte layer is not particularly limited. As in the invention described in claim 5, the positive electrode layer and the negative electrode layer can be laminated on the support so as not to overlap in the lamination direction. By forming the positive electrode layer and the negative electrode layer so as not to overlap with each other, there is no risk of a short circuit due to pinholes in the thickness direction of the solid electrolyte layer, and a stable battery with low performance deterioration can be provided.

  As the above laminated form, there are a case where one electrode layer is directly formed on a metal current collector, and a case where one electrode layer is formed directly on an insulating substrate or via a current collector.

  In the former case, the current collector is made of metal, and one electrode layer is formed directly on a part of the current collector without an electric insulating layer, and the current collector other than the portion where the one electrode layer is formed is formed. An electrical insulating layer is formed on the surface of the electric body. Then, a solid electrolyte layer is formed on the one electrode layer and the electrical insulating layer in a spanning manner. In this laminated form, the stepped form between the one electrode layer and the electrically insulating layer is relaxed by the chamfered portion, so that the solid electrolyte layer can be prevented from being cut near the stepped portion.

  In the latter case, a current collector is formed on a part of the insulating substrate, and an electrode layer is formed so as to cover the current collector, or one electrode layer is formed directly on a part of the insulating substrate. . And the said solid electrolyte layer is formed in a spanning form on one electrode layer and an insulated substrate. Also in the case of this laminated form, the stepped form between the one electrode layer and the insulating substrate is relaxed by the chamfered portion, so that the film breakage of the solid electrolyte layer can be prevented.

  According to a sixth aspect of the present invention, the chamfered portion is formed at an angle of 20 ° to 70 ° with respect to the support surface. In particular, when each electrode portion is formed in a substantially trapezoidal shape, it is desirable to set the angle of the hypotenuse within the above range.

  When the angle of the chamfered portion is set to 20 ° or less, the thickness of the edge portion of the electrode portion is reduced, and the area of the electrode layer is increased to ensure the same cross-sectional area. In particular, in the case of an electrode having a linear portion with a predetermined width, the width of each linear portion becomes too large. For this reason, the danger of the increase in a battery dimension and the short circuit with the other adjacent electrode increases.

  On the other hand, when the chamfered portion is set to 70 ° or more, it becomes difficult to reliably form the solid electrolyte layer on the inclined surface, and the risk of the solid electrolyte layer being broken is increased.

  The invention described in claim 7 is a method of manufacturing a solid thin film battery comprising a positive electrode layer, a negative electrode layer, a solid electrolyte layer disposed between these layers, and a support on which each of these layers is laminated and held. An electrode layer lamination forming step of laminating the positive electrode layer or / and the negative electrode layer on the surface of the support, and a chamfered portion forming step of forming a chamfered portion at a side edge of the positive electrode layer or / and the negative electrode layer; A solid electrolyte layer forming step of forming a solid electrolyte between the positive electrode layer and the negative electrode layer.

  Each of the above steps is not limited to one time, and a plurality of the same steps can be performed according to the battery stacking form. Moreover, when using an electrically insulating support body, the current collection layer formation process which forms a current collection layer can be included.

  The chamfered portion can be provided only on one of the positive electrode layer and the negative electrode layer, or can be provided on both. When both are provided, the chamfered portion can be formed in all the electrode layers in one chamfered portion forming step, or two or more chamfered portion forming steps are performed according to the positive and negative electrode layer forming steps. You can also.

  The method for performing the chamfered portion forming step is not particularly limited. For example, the chamfered portion can be formed on the edge portion of the electrode layer on the support using a press die having a chamfered portion forming mold portion corresponding to the form of the electrode.

  Moreover, like the invention described in Claim 8, the said chamfered part formation process can be performed by roll-pressing the support body in which the electrode layer was formed.

  For example, the opposing gaps of the roll presses arranged on the top and bottom are set to 10 μm to 200 μm smaller than the total thickness of the electrode and the support formed by laminating the electrodes, and pressing is performed, so that the required edge portions of the electrode layers are required. A chamfered portion can be formed. In addition, when press-working, in order to increase the lamination strength (peeling strength) of an electrode layer and a support body, it is preferable to heat and perform press work. For example, when processing the positive electrode layer, it is preferable to perform the press processing while heating to a temperature lower by 10 to 100 ° C. than the melting point of the binder contained therein.

  Since there is no problem such as film breakage of the solid electrolyte layer, there is little deterioration in battery performance, and a solid thin film battery with stable quality can be formed.

  Hereinafter, embodiments of the present invention will be specifically described.

  FIG. 1 shows a cross-sectional view of a solid-state thin film battery according to the first embodiment of the present invention.

  The solid thin film battery 1 according to the first embodiment is obtained by applying the present invention to a lithium solid thin film battery. In the solid thin film battery 1, a current collector 3 is patterned with a metal thin film on an electrically insulating support 2, and a positive electrode layer 4 is formed so as to cover the current collector. A solid electrolyte layer 5 is laminated and formed so as to cover the positive electrode layer 4, and a negative electrode layer 6 is laminated and formed on the solid electrolyte layer 5 at a position that does not overlap the positive electrode layer 4.

  Although the conventional positive electrode layer has a substantially rectangular cross section, in the present embodiment, both corners have an angle of about 50 ° with respect to the surface of the support 2 so that the cross sectional shape is substantially trapezoidal. Chamfered portions 7 and 7 formed of inclined surfaces are formed.

  As is apparent from FIG. 1, by providing the chamfered portions 7 and 7, the upper surface of the positive electrode layer 4 and the surface of the support 2 are connected via the chamfered portions 7 and 7. By providing the chamfered portions 7 and 7, the solid electrolyte layer 5 having the same thickness as the other portions can be laminated on the stepped portion formed between the positive electrode layer 4 and the support 2. Take possible. For this reason, it becomes possible to prevent the film breakage of the solid electrolyte layer 5 at the stepped portion between the positive electrode layer 4 and the support, and a solid thin film battery having a stable quality and a good yield can be formed.

  In addition, even when the solid thin film battery 1 is bent, the stress and deformation acting on the side edge of the positive electrode layer 4 can be relaxed, so that the positive electrode layer 4 and the surface of the support 2 The lamination strength of can be substantially increased.

  Furthermore, since the solid electrolyte layer 5 can be formed with a uniform thickness at the stepped-down portion, stress and deformation acting on the solid electrolyte layer laminated in the vicinity of the chamfered portion are also alleviated. Therefore, when the battery is bent or the like, an effect of preventing cracks or the like from occurring in the solid electrolyte layer can be expected.

  The inclination angle T of the chamfered portion is preferably set in a range of 20 ° to 70 ° with respect to the support surface. When the inclination angle is 20 ° or less, the width of the solid electrolyte layer becomes too large during press working. On the other hand, when the angle is set to 70 ° or more, the solid electrolyte layer easily breaks. In addition, the said chamfering part is not limited to the said embodiment, The thing of a various form is employable.

  In the present embodiment, since the positive electrode layer 4 and the negative electrode layer 6 are arranged so as not to overlap each other in the thickness direction of each layer, the pin is attached to the solid electrolyte layer 5 interposed between both electrode layers. Even if holes or the like are formed, there is no fear that both electrode layers are short-circuited. Further, the solid electrolyte layer 5 is located on the lower surface of the negative electrode layer 6. The lower surface of the solid electrolyte layer 5 is an electrically insulating support 2, and the current collector on the positive electrode layer side. 3 are arranged so as not to overlap with each other, there is no possibility that the negative electrode layer 6 is short-circuited to the current collector 3 even if there is a pinhole in the solid electrolyte layer 5 located below the negative electrode layer 6. . Therefore, it becomes possible to provide a solid thin film battery with more stable quality.

  Various substrate materials can be employed as the electrically insulating support 5. For example, an electrically insulating resin film used for a flexible wiring board, for example, a polyimide resin film can be used as the support.

  There are no particular limitations on the material and the forming method of the current collector 3. For example, a metal such as Ni or Co can be formed in a predetermined pattern on the surface of the support 2 by a wet process such as electroless plating or a dry process such as sputtering or vapor deposition.

  The positive electrode layer 4 is composed of a layer containing an active material that occludes and releases lithium ions. For example, active materials such as lithium manganate (LiMnO2) and lithium cobaltate (LiCOO2) can be used alone or in a mixture. Further, sulfides such as iron sulfide (FeS, FeS2) can be used alone or as a mixture. Carbon particles can be used as the conductive powder, and polyvinylidene fluoride or Teflon can be used as the binder. The positive electrode layer 4 can be formed using a wet method such as a sol-gel method or a colloid, or a dry method such as a vapor deposition method or a sputtering method.

  Alternatively, the above positive electrode powder, conductive powder, binder, etc. may be dispersed in a solvent such as N-methyl-2pyrrolidone, applied in a predetermined pattern, and then heated to about 150 ° C. and dried. it can. The positive electrode layer 4 formed by this technique is a porous body, and the conductivity on the positive electrode side can be increased by impregnating the void portion with an ionic liquid.

  Similarly to the positive electrode layer 4, the negative electrode layer 6 is also composed of a layer containing an active material that occludes and releases lithium ions. The negative electrode layer 6 is preferably formed of Li metal or a metal capable of forming an alloy with Li metal alone or in a mixture. For example, lithium simple substance (Li), lithium (Li) -aluminum (Al) alloy, lithium (Li) -manganese (Mn) -aluminum (Al) alloy, etc. can be employed. Alternatively, an alloy such as silicon simple substance (Si), silicon (Si) -nickel (Ni), silicon (Si) -cobalt (Co), silicon (Si) -iron (Fe), or the like may be employed. The negative electrode layer 6 can also be laminated on the solid electrolyte layer 5 in the same manner as the positive electrode layer.

  As the solid electrolyte layer 5, an amorphous film or a polycrystalline film made of Li—PS—O can be adopted. Further, an amorphous film or a polycrystalline film made of Li—P—O—N can also be used as the negative electrode side electrolyte.

  FIG. 2 shows a cross-sectional view of a solid-state thin film battery according to the second embodiment of the present invention.

  The solid thin film battery 201 according to the second embodiment employs a metal film such as aluminum (Al), nickel (Ni), and stainless steel as the support 202 that is also used as a current collector. A positive electrode layer 204 and an electrical insulating layer 208 are provided on the support 202, and a solid electrolyte layer 205 is formed between the two layers. Further, the solid electrolyte layer 205 overlaps with the positive electrode layer 204. A negative electrode layer 206 is laminated and formed at a position where it does not become necessary. Note that the material, configuration, and the like of each layer are the same as those described in the first embodiment, and a description thereof will be omitted.

  The positive electrode layer 204 is formed in a predetermined pattern on the surface of the support 202, and the electrical insulating layer 208 is formed on a portion of the support surface where the positive electrode layer 204 is not formed. The positive electrode layer 204 is set to be thicker than the electric insulating layer 208, and the upper portion of the positive electrode layer 204 has a form protruding from the electric insulating layer 208.

  A chamfered portion 207 having a circular arc cross section is formed on the side edge of each positive electrode layer 204. As is apparent from FIG. 2, by providing the arc-shaped chamfered portion 207, the solid electrolyte layer 205 can be formed in a substantially uniform thickness at these stepped portions, and the solid portions in these portions can be formed. The film breakage of the electrolyte layer 205 can be prevented. Further, in this laminated form, since the electric insulating layer 208 is provided on the surface of the support 202 where the positive electrode layer 204 is not formed, the step height between the positive electrode layer 204 and the electric insulating layer 208 is reduced. By setting a small value, an effect of preventing the solid electrolyte layer 205 from being broken can be expected.

  The form of the cross-section arc shape of the chamfered portion 207 is not particularly limited, and a form in which the solid electrolyte layer 205 can be surely laminated and formed with a predetermined thickness may be adopted. In addition, an arc-shaped chamfered portion having a shape opposite to that of the chamfered portion 207 is formed at the boundary between the positive electrode layer 204 and the surface of the support 202, and the lamination strength of the positive electrode layer 204 and the support 202 is increased. Can also be increased.

  FIG. 3 shows a cross-sectional view of a solid-state thin film battery according to the third embodiment of the present invention.

  In the solid thin film battery 301 according to the third embodiment, the positive electrode side current collector 303a and the negative electrode side current collector 303b are stacked on the surface of the electrically insulating support 302 with a predetermined distance therebetween. A positive electrode layer 304 and a negative electrode layer 306 are stacked on the current collectors 303 a and 303 b, respectively, and a solid electrolyte layer 305 is stacked on the surfaces of the electrode layers 303 a and 303 b and the support 302. Yes. Note that the material, configuration, and the like of each layer are the same as those described in the first embodiment, and a description thereof will be omitted.

  In the third embodiment, the chamfered portions 307a and 307b are provided on the side edge portions of the positive electrode layer 304 and the negative electrode layer 306, so that the cross-sectional shapes of both the electrode layers 304 and 306 are formed in a substantially trapezoidal shape. Thereby, similar to the first embodiment and the second embodiment, the solid electrolyte layer is prevented from being cut off due to a step between the electrode layers 304 and 306 and the surface of the support 302. be able to.

  Also in this embodiment, since the positive electrode layer 304 and the negative electrode layer 306 do not overlap in the stacking direction, the two electrode layers are short-circuited even if a pinhole or the like exists in the solid electrolyte layer 305. There is no fear.

  Based on FIG.4 and FIG.5, the manufacturing method of the solid thin film battery which concerns on 1st Embodiment is demonstrated.

  The solid thin film battery 1 includes a current collector stacking step in which the positive electrode side current collector 3 is stacked on the surface of the support 2 in a predetermined comb-like pattern, and the support 3 so as to cover the current collector 3. A chamfered portion 7 is formed on the side edge of the positive electrode layer 4 by roll pressing the positive electrode layer forming step of forming the positive electrode layer 4 on the surface of the body 2 and the support on which the positive electrode layer 4 is laminated. A chamfered portion forming step, a solid electrolyte layer forming step of laminating and forming a solid electrolyte layer 5 in a predetermined region of the positive electrode layer 4 and the support 2 on which the chamfered portion 7 is formed, and the solid electrolyte layer 5 laminated above A negative electrode layer forming step of forming the negative electrode layer 6 at a position not overlapping the positive electrode layer 4 is performed in this order.

  As shown in FIG. 4, a roller press device 10 is used in which a laminated body 1a on which the positive current collector 3 and the positive electrode layer 4 are formed is opposed to a pair of rollers 10a and 10b with a predetermined gap therebetween. The chamfered portion forming step is performed by pressing.

  The pair of rollers is set to be 10 μm to 200 μm smaller than the thickness of the stacked body 1 a in which the support 2 and the positive electrode layer 4 are stacked. When the laminated body 1a is pressed through the pair of rollers 10a and 10b in a direction perpendicular to the side edge of the linearly formed positive electrode layer 4, the longitudinal direction of the linear positive electrode layer 4 is increased. The corner portions are pressed and deformed to form the chamfered portions 7 and 7 shown in FIG. 5, and the positive electrode layer 4 having a substantially trapezoidal cross section can be formed. In order to increase the lamination strength (peeling strength) between the positive electrode layer 4 and the support 2, the rollers 10 a and 10 b are heated to a temperature 10 ° C. to 100 ° C. lower than the melting point of the binder contained in the positive electrode layer. However, it is preferable to perform press working.

  Next, a solid electrolyte layer forming step is performed in which the solid electrolyte layer is laminated and formed in a predetermined region where the positive electrode layer of the support is formed. Thereafter, a negative electrode layer forming step is performed in which the negative electrode layer is formed on the surface of the solid electrolyte layer at a position that does not overlap with the positive electrode layer, that is, between the adjacent positive electrode layers, thereby forming a solid thin film battery. Note that the current collector forming step, the positive electrode layer forming step, the solid electrolyte layer forming step, and the negative electrode layer forming step are performed using the same method as described above, and thus description thereof is omitted.

  Thereafter, a sealing film is disposed on one side or both sides of the solid thin film battery and roll-pressed, and the peripheral portion of the sealing film is thermocompression-bonded to the other sealing film or the support 2, thereby packaging. The battery is completed.

  In the solid-state thin film battery 1 having the laminated structure according to the first embodiment formed by the above manufacturing method, the operation and effect by providing the chamfered portion 7 will be described based on the following embodiments and comparative examples. .

〔Example〕
1. Support PPS thickness 50μm
2. Positive electrode layer MnO2 grain + carbon black + PVDF thickness 100μm
3. Positive electrode layer impregnated ionic liquid EMI-FSI
4). Solid electrolyte layer Li2 S + P2 S5 thickness 3 μm
5. Negative electrode layer Li metal film thickness 25μm
6). Structure Power generation unit 3cm ²
Electrode line width 0.5mm
Gap width between positive and negative electrode layers 0.3mm
7). Cross-sectional shape of positive electrode layer Sectional trapezoidal shape including a chamfered portion with an inclination angle T = 60 ° with the support surface. 8. Manufacturing method of chamfered portion After the positive electrode layer is applied and formed, roll pressing is performed by applying a 1 ton pinching pressure to the upper and lower rollers. Aluminum laminate foil was provided on both sides of the battery and roll pressed at a temperature of 120 ° to seal the peripheral edge of the aluminum laminate foil by thermocompression bonding.

[Comparative example]
1. Support PPS thickness 50μm
2. Positive electrode layer MnO2 grain + carbon black + PVDF thickness 100μm
3. Positive electrode layer impregnated ionic liquid EMI-FSI
4). Solid electrolyte layer Li2 S + P2 S5 thickness 3 μm
5. Negative electrode layer Li metal film thickness 25μm
6). Structure Power generation unit 3cm ²
Electrode layer line width 0.5mm
Gap width between positive and negative electrode layers 0.3mm
7). Cross-sectional shape of positive electrode Form of rectangular cross-section with angle T = 90 ° with support surface 8. No roll press processing 9. Aluminum laminate foil was provided on both sides of the battery and roll pressed at a temperature of 120 ° to seal the peripheral edge of the aluminum laminate foil by thermocompression bonding.

〔Comparison result〕
1. About the solid thin film battery which concerns on an Example and a comparative example, the voltage fall at the time of 1 mA discharge was measured.
In the example of the present application provided with the chamfered portion, the voltage drop was 0.1 V, whereas in the comparative example in which the chamfered portion was not formed, it was 0.6 V.
2. When the solid thin film batteries according to the examples and the comparative example were observed with a microscope, the solid electrolyte layer was cut off at the side edge on the positive electrode side of the solid thin film battery according to the comparative example. On the other hand, in the solid thin film battery according to the example, the solid electrolyte layer was formed without film breakage on the side edge of the positive electrode layer.

  As is clear from the comparison results between the above example and the above comparative example, the provision of the chamfered portion eliminates the film breakage of the solid electrolyte layer at the stepped portion between the positive electrode layer and the support, thereby greatly reducing the voltage drop. It was found that it can be improved. Therefore, a solid thin film battery with stable performance can be manufactured with high yield. In addition, even when the battery is bent, stress and deformation are less likely to concentrate on the edge of the electrode layer and the solid electrolyte layer in the vicinity of the stepped portion, and peeling of the electrode layer and generation of cracks in the solid electrolyte layer occur. Thus, a highly flexible battery can be manufactured at low cost.

  The present invention is not limited to the embodiment described above. It should be thought that embodiment disclosed this time is an illustration and restrictive at no points. The scope of the present invention is defined not by the above-described meaning but by the scope of the claims, and is intended to include all modifications within the meaning and scope equivalent to the scope of the claims.

  According to the present invention, a solid thin film battery that can exhibit stable performance and has a high yield can be manufactured at low cost.

It is sectional drawing of the solid thin film battery which concerns on the 1st Embodiment of this invention. It is sectional drawing of the solid thin film battery which concerns on 2nd Embodiment of this invention. It is sectional drawing of the solid thin film battery which concerns on 3rd Embodiment of this invention. It is a perspective view which shows the outline | summary of the chamfer part formation process in the manufacturing method of the solid thin film battery which concerns on this invention. It is sectional drawing which shows the outline | summary of the chamfer part formation process in the manufacturing method of the solid thin film battery which concerns on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Solid thin film battery 2 Support body 4 Positive electrode layer 5 Solid electrolyte layer 6 Negative electrode layer 7 Chamfer

Claims (8)

A solid thin film battery comprising a positive electrode layer, a negative electrode layer, a solid electrolyte layer disposed between these layers, and a support on which each of these layers is laminated and held,
A solid thin film battery in which a chamfered portion is provided on a side edge of the positive electrode layer and / or the negative electrode layer.   The solid thin film battery according to claim 1, further comprising a solid electrolyte layer formed in a spanning manner between the electrode layer and another region having a step in the thickness direction via the chamfered portion.   The solid film battery according to claim 1, wherein the positive electrode layer and / or the negative electrode layer includes the chamfered portion having a substantially trapezoidal cross section.   The positive electrode layer and / or the negative electrode layer includes a linear portion having a predetermined width, and at least the chamfered portion is provided at a longitudinal side edge of the linear portion. The solid thin film battery described in 1.   5. The solid thin film battery according to claim 1, wherein the positive electrode layer and the negative electrode layer are stacked on the support so as not to overlap in the stacking direction.   6. The solid thin film battery according to claim 1, wherein the chamfered portion is formed at an angle of 20 ° to 70 ° with respect to the support surface. A method for producing a solid thin film battery comprising a positive electrode layer, a negative electrode layer, a solid electrolyte layer disposed between these layers, and a support on which each of these layers is laminated and held,
An electrode layer stacking step of stacking the positive electrode layer or / and the negative electrode layer on the support surface;
A chamfered portion forming step of forming a chamfered portion on a side edge of the positive electrode layer or / and the negative electrode layer;
A method for producing a solid thin film battery, comprising: a solid electrolyte layer forming step of forming a solid electrolyte between the positive electrode layer and the negative electrode layer.   The said chamfer part formation process is a manufacturing method of the solid thin film battery of Claim 7 performed by roll-pressing the support body in which the said electrode layer was formed.

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