JP2012074201A - Lithium ion secondary battery, vehicle, electronic device and manufacturing method of lithium ion secondary battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lithium ion secondary battery having a current collector with an active material layer stacked thereon, in which the exfoliation of the active material layer from the current collector is suppressed.SOLUTION: In the lithium ion secondary battery, the active material layer 12 has a stripe structure which includes line patterns 121 spaced apart from each other and arrayed in parallel with each other on a surface of a current collector layer 11. The length La of parts of the line patterns 121 in contact with the surface of the current collector layer 11 in a longer direction Y of the line pattern 121 is not less than four times as large as the width Da of parts of the line patterns 121 in contact with the surface of the current collector layer 11 in a direction X of the width. A wider contact area of the active material layer 12 and the surface of the current collector layer 11 is arranged like this and therefore, the exfoliation of the active material layer 12 from the current collector layer 11 can be suppressed efficiently.

Description

  The present invention relates to a lithium ion secondary battery in which an electrolyte layer is interposed between positive and negative electrode active materials, a vehicle and an electronic device including the same, and a method for manufacturing the battery.

  Conventionally, as such a lithium ion secondary battery, a current collector in which a positive electrode active material is laminated and a current collector in which a negative electrode active material is laminated are prepared, and a separator impregnated with an electrolytic solution is provided for each current collector. It is known that it is sandwiched between the two. However, as pointed out in Patent Documents 1 and 2 and the like, in a lithium ion secondary battery in which an active material is stacked on a current collector, there is a problem that the active material is separated from the current collector.

  That is, Patent Document 1 points out that the active material peels from the current collector because the adhesion between the active material and the current collector is insufficient. Further, in Patent Document 2, when a groove is provided in the active material layer in order to increase the contact area between the active material layer and the electrolytic solution, the active material layer is separated from the current collector due to the groove. It is pointed out.

  In order to cope with such a problem, in Patent Document 1, the active material is covered with a conductive protective film, thereby improving the adhesion between the active material and the current collector, and peeling the active material from the current collector. Suppressed. Moreover, in patent document 2, peeling of the active material layer from a collector is suppressed by keeping the edge of a groove | channel away from the periphery of an active material layer.

JP 2008-117574 A (for example, paragraphs 0011, 0013, 0014) JP 2008-277242 A (for example, paragraph 0005)

  However, in Patent Document 1, since a member called a conductive protective film is required separately, there is a risk that the cost may be increased, and the conductive protection is performed so that the adhesion between the active material layer and the current collector can be reliably obtained. It is necessary to cover the active material layer exactly with a film, and there is a possibility that the manufacturing process becomes complicated. Further, in Patent Document 2, even if it is effective for the cause of the groove of the active material layer, it is not necessarily effective when the active material layer is separated from the current collector due to other causes. It was.

  The present invention has been made in view of the above problems, and it is an object of the present invention to provide a technique capable of suppressing separation of an active material layer from a current collector in a lithium ion secondary battery in which an active material layer is stacked on a current collector. And

  In order to achieve the above object, a lithium ion secondary battery according to the present invention includes a first current collector layer, a first active material layer, an electrolyte layer, a second active material layer, and a second current collector layer. Are stacked in this order, and the first active material layer has a stripe structure in which a plurality of line-shaped patterns spaced apart from each other are arranged in parallel on the surface of the first current collector layer. The length dimension of the line-shaped pattern in contact with the first current collector layer surface in the longitudinal direction of the line-shaped pattern is equal to the width dimension of the line-shaped pattern in contact with the first current collector layer surface in the width direction orthogonal to the longitudinal direction. It is characterized by four times or more.

  In the invention thus configured (lithium ion secondary battery), the first active material layer has a stripe structure in which a plurality of line-shaped patterns separated from each other are arranged in parallel on the surface of the first current collector layer. have. Moreover, the length of the line-shaped pattern in contact with the surface of the first current collector layer in the longitudinal direction of the line-shaped pattern is equal to the length of the line-shaped pattern in contact with the surface of the first current collector layer in the width direction orthogonal to the longitudinal direction. It is at least four times the width dimension. As described above, in the present invention, the contact area between the first active material layer and the surface of the current collector layer is wide, and it is possible to effectively suppress peeling of the active material layer from the current collector layer. It has become.

  Moreover, you may comprise so that the height dimension of the line-shaped pattern from the 1st collector layer surface may be smaller than a width dimension. In this manner, by suppressing the height of the line pattern, it is possible to more effectively suppress the peeling of the active material layer from the current collector.

  The lithium ion secondary battery having the above-described structure can be applied in various fields. For example, an electronic circuit unit that operates as a power source for various vehicles such as an electric vehicle and uses the lithium ion secondary battery as a power source. It is possible to apply to various electronic devices provided with.

  Further, in order to achieve the above object, a method for manufacturing a lithium ion secondary battery according to the present invention has a stripe structure in which a plurality of line-shaped patterns separated from each other are arranged in parallel on the surface of the first current collector layer. A first step of forming a first active material layer having a second layer, and an electrolyte layer, a second active material layer, and a second current collector layer are laminated in this order on the surface of the first active material layer A line in which the length dimension of the line-shaped pattern in contact with the surface of the first current collector layer in the longitudinal direction of the line-shaped pattern is in contact with the surface of the first current collector layer in the width direction orthogonal to the longitudinal direction. It is characterized by being at least four times the width dimension of the pattern.

  In the invention configured as described above (a method for manufacturing a lithium ion secondary battery), the first active material layer includes a plurality of line-shaped patterns arranged in parallel to each other on the surface of the first current collector layer. The stripe structure is as follows. Moreover, the length of the line-shaped pattern in contact with the surface of the first current collector layer in the longitudinal direction of the line-shaped pattern is equal to the length of the line-shaped pattern in contact with the surface of the first current collector layer in the width direction orthogonal to the longitudinal direction. It is at least four times the width dimension. As described above, in the present invention, the contact area between the first active material layer and the current collector layer surface is wide, and it is possible to effectively suppress peeling of the active material layer from the current collector. It has become.

  In the present invention, the contact area between the first active material layer and the current collector layer surface is wide, and it is possible to effectively suppress peeling of the active material layer from the current collector. .

It is a figure which shows schematic structure of a lithium ion secondary battery. 2 is a flowchart illustrating an example of a method for manufacturing the battery of FIG. It is a figure which shows typically the mode of material application by the nozzle scan method. It is an expanded sectional view which shows the cross-sectional shape of a negative electrode active material layer. It is a figure which shows typically the difference with the structure of FIG. 4, and the structure of the conventional battery module. It is a figure which shows the example of the other pattern of a negative electrode active material layer. It is a figure which shows typically the electric vehicle carrying the battery concerning this invention. It is a figure which shows typically the IC card carrying the battery concerning this invention.

  FIG. 1 is a diagram showing a schematic structure of a lithium ion secondary battery. More specifically, FIG. 1A is a diagram showing a cross-sectional structure of a lithium ion secondary battery module as one embodiment of the present invention, FIG. 1B is an overview perspective view thereof, and FIG. ) Is an external perspective view showing only the negative electrode current collector and the negative electrode active material layer. The lithium ion secondary battery module 1 has a structure in which a negative electrode active material layer 12, a solid electrolyte layer 13, a positive electrode active material layer 14, and a positive electrode current collector 15 are sequentially laminated on a negative electrode current collector 11. Yes. In this specification, the X, Y, and Z coordinate directions are defined as shown in FIG.

  As shown in FIGS. 1B and 1C, the negative electrode active material layer 12 has a line-and-space structure in which a large number of line-shaped patterns 121 extending along the Y direction are arranged at regular intervals in the X direction. (Stripe structure). The solid electrolyte layer 13 is formed of a solid electrolyte, and the lower surface thereof has an uneven shape corresponding to the unevenness of the negative electrode active material layer 12, while the upper surface is substantially flat.

  The line pattern 121 of the negative electrode active material layer 12 formed on the surface of the negative electrode current collector 11 has the following dimensional relationship. That is, the length dimension La of the line-shaped pattern 12 that contacts the surface of the negative electrode current collector 11 in the longitudinal direction Y of the line-shaped pattern 12 is a line shape that contacts the surface of the negative electrode current collector 11 in the width direction X orthogonal to the longitudinal direction Y. It is 4 times or more the pattern width dimension Da (La ≧ 4 × Da). As described above, in this embodiment, the contact area between the negative electrode active material layer 12 and the surface of the negative electrode current collector 11 is wide, and the peeling of the negative electrode active material layer 12 from the negative electrode current collector 11 is effectively suppressed. It is possible to do.

  Further, the height dimension Ha of the line-shaped pattern 12 from the surface of the negative electrode current collector 11 is smaller than the width dimension Da of the line-shaped pattern 12 (Ha <Da). Thus, in this embodiment, it is possible to more effectively suppress the peeling of the negative electrode active material layer 12 from the negative electrode current collector 11 by suppressing the height of the line pattern 12.

  Then, the positive electrode active material layer 14 and the positive electrode current collector 15 are laminated on the solid electrolyte layer 13 formed substantially flat in this manner, so that the lithium ion secondary battery module 1 is formed. The lithium ion secondary battery module 1 is appropriately provided with a tab electrode, or a plurality of modules are stacked to constitute a lithium ion battery.

Here, as a material constituting each layer, for example, a copper foil or an aluminum foil can be used as the negative electrode current collector 11 and the positive electrode current collector 15, respectively. Further, as the positive electrode active material, for example, a material mainly composed of LiCoO ₂ (LCO) can be used, and as the negative electrode active material, for example, a material mainly composed of Li ₄ Ti ₅ O ₁₂ (LTO) can be used. Moreover, as the solid electrolyte layer 13, for example, polyethylene oxide and polystyrene can be used.

  The lithium ion secondary battery module 1 having such a configuration (composition and structure) is thin and easy to bend. Further, since the negative electrode active material layer 12 has a three-dimensional structure having irregularities as illustrated, the surface area with respect to the volume is increased, so that the surface area facing the positive electrode active material layer 14 through the thin solid electrolyte layer 13 is increased. High efficiency and high output can be obtained. Thus, the lithium ion battery having the above-described structure is small and can obtain high performance.

  Next, a method for manufacturing the above-described lithium ion secondary battery module 1 will be described. Conventionally, this type of module has been formed by laminating thin film materials corresponding to each functional layer. However, this manufacturing method has a limit in increasing the density of the module. Moreover, in the manufacturing method proposed conventionally (for example, Unexamined-Japanese-Patent No. 2005-116248), there are many processes and manufacturing takes time, and isolation | separation between each functional layer is difficult. On the other hand, in the manufacturing method described below, the lithium ion battery module 1 having the above-described structure can be manufactured with a small number of steps and using an existing processing apparatus.

  FIG. 2 is a flowchart showing an example of a method for manufacturing the battery of FIG. In this manufacturing method, first, a metal foil, such as a copper foil, to be the negative electrode current collector 11 is prepared (step S101). Since thin copper foils are difficult to transport and handle, it is preferable to improve transportability, for example, by attaching one side to a carrier such as a glass plate.

  Subsequently, a coating liquid containing a negative electrode active material is applied to one surface of the copper foil by a nozzle dispensing method, particularly a nozzle scanning method in which a nozzle for discharging the coating liquid is moved relative to the surface to be coated (step S102). As the coating solution, for example, an organic LTO material containing the negative electrode active material described above can be used. In addition to the negative electrode active material, the coating solution includes acetylene black (AB) or ketjen black as a conductive auxiliary agent, polyvinylidene fluoride (PVDF), styrene butadiene rubber (SBR), polyvinyl pyrrolidone (PVP) as a binder. ), Polyvinyl alcohol (PVA) or polytetrafluoroethylene (PTFE), N-methyl-2-pyrrolidone (NMP) as a solvent, and the like can be used. In the coating liquid used for the trial production of the examples described later, the composition ratio of LTO: AB: PVDF was about 8: 1: 1.

  FIG. 3 is a diagram schematically showing a state of material application by the nozzle scanning method. More specifically, FIG. 3 (a) is a view of the state of application by the nozzle scanning method as seen from the X direction, and FIGS. 3 (b) and 3 (c) are views of the same state as seen from the Y direction and obliquely from above. It is. A technique for applying a coating solution to a substrate by a nozzle scanning method is known, and such a known technique can also be applied to this method, and thus the description of the apparatus configuration is omitted.

  In the nozzle scanning method, a nozzle 31 having one or a plurality of discharge ports 311 for discharging the organic LTO material as a coating solution is disposed above the copper foil 11 and a certain amount of coating is applied from the discharge port 311. While discharging the liquid 32, the nozzle 31 is moved relative to the copper foil 11 at a constant speed in the arrow direction Dn. By doing so, the coating liquid 32 is applied onto the copper foil 11 in a line shape along the Y direction. By providing a plurality of discharge ports 311 in the nozzle 31, a plurality of stripes can be formed by a single scanning movement, and by repeating the scanning movement as necessary, the coating liquid is formed in a line on the entire surface of the copper foil 11. Can be applied. By drying and curing this, a line pattern 121 made of a negative electrode active material is formed on the upper surface of the copper foil 11. Alternatively, a photo-curable resin may be added to the coating solution and cured by light irradiation after coating.

  At this time, the negative electrode active material layer 12 is partially raised with respect to the surface of the substantially flat copper foil 11, compared with a case where the coating liquid is simply applied so that the upper surface is flat, Since the surface area with respect to the usage amount of the active material can be increased, the facing area with the positive electrode active material to be formed later can be increased to obtain a high output.

The description of the flowchart of FIG. 2 will be continued. An electrolyte coating solution is applied to the upper surface of the laminate formed by laminating the negative electrode active material layer 12 on the copper foil 11 thus formed by an appropriate coating method, for example, a knife coating method or a bar coating method (step S103). . As the electrolyte coating solution, a mixture of the above-described polymer electrolyte material, for example, a resin such as polyethylene oxide or polystyrene, a support salt such as LiPF ₆ and a solvent such as diethylene carbonate can be used. Although it is not limited to the above as a coating method here, It is preferable that it is a method which can make the surface after application | coating substantially flat.

  Subsequently, a positive electrode active material layer 14 and an aluminum foil 15 as a positive electrode current collector are laminated. Here, an example will be described. First, a substantially uniform positive electrode active material layer 14 is formed on the surface of the aluminum foil 15 by previously applying a coating liquid containing a positive electrode active material to the aluminum foil 15 as a positive electrode current collector. Examples of the coating liquid containing the positive electrode active material include, for example, the above-described positive electrode active material, acetylene black as a conductive additive, SBR as a binder, carboxymethyl cellulose (CMC) as a dispersant, and pure water as a solvent. A water-based LCO material mixed with the above can be used. In addition to the knife coating method and bar coating method described above, a known coating method capable of forming a flat film on a flat surface, such as a spin coating method, can be employed as appropriate. .

  Then, before the electrolyte coating solution applied in step S103 is cured, the aluminum foil 15 on which the positive electrode active material layer 14 is formed is bonded to bring the positive electrode active material layer 14 and the electrolyte coating solution into close contact (step S104). ). At this time, in order to further improve the adhesion, an electrolyte coating solution may be applied to the positive electrode active material layer 14 on the surface of the aluminum foil 15.

  In this way, the lithium ion secondary battery module 1 in which the negative electrode current collector 11, the negative electrode active material layer 12, the solid electrolyte layer 13, the positive electrode active material layer 14, and the positive electrode current collector 15 are sequentially stacked is formed. . In addition to the above method, for example, after applying the electrolyte coating solution, and curing this to form the solid electrolyte layer 13, a coating solution containing a cathode active material is applied to form the cathode active material layer 14, Further, the positive electrode current collector 15 may be bonded.

  Next, the structure of the negative electrode active material layer in the lithium ion secondary battery module 1 of FIG. 1 will be described in more detail with reference to FIGS. FIG. 4 is an enlarged cross-sectional view showing a cross-sectional shape of the negative electrode active material layer. FIG. 5 is a diagram schematically showing the difference between the structure of FIG. 4 and the structure of the conventional battery module.

  As shown in FIG. 1, the negative electrode active material layer 12 in this embodiment has a structure in which a plurality of line-shaped patterns 121 extending in the Y direction are arranged in islands separated from each other in the X direction. FIG. 4 shows a cross section of the line-shaped pattern 121 cut along the XZ plane. As shown in the figure, the surface of the line-shaped pattern 121 is a smooth curved surface convex upward (Z direction). Yes.

  Typical dimensions of each part in the battery module 1 prototyped by the inventors of the present application are a line pattern 121 having a width Da of about 170 μm and a height Ha of about 100 μm. Further, the distance S between the adjacent line patterns 121, 121 is about 160 μm. The thickness Hd of the solid electrolyte layer 13 is about 200 μm.

  Further, the line pattern 121 at the contact point P where the three of the negative electrode current collector 11, the negative electrode active material line pattern 121, and the solid electrolyte layer 13 come into contact with each other, that is, the position where the line pattern 121 rises from the negative electrode current collector 11. Of the angles formed by the surface gradient, in other words, the tangent line drawn to the line-shaped pattern 121 at the contact point P and the negative electrode current collector layer 11, the angle θ on the side including the line-shaped pattern 121 is smaller than 90 degrees. Hereinafter, in this specification, this angle θ is referred to as a “contact angle”.

  According to the knowledge of the inventors of the present application, the preferred ranges of the dimensions of the respective parts where good characteristics are obtained as a battery are as follows. That is, the line pattern 121 has a width Da of 20 μm to 300 μm, a height Ha of about 10 μm to 300 μm, and a cross-sectional aspect ratio, that is, a ratio of the height Ha to the width Da of 0.5 or more. preferable. That is, the length dimension La of the line-shaped pattern 12 that contacts the surface of the negative electrode current collector 11 in the longitudinal direction Y of the line-shaped pattern 12 is a line shape that contacts the surface of the negative electrode current collector 11 in the width direction X orthogonal to the longitudinal direction Y. It is 4 times or more the pattern width dimension Da (La ≧ 4 × Da). Thus, the contact area between the negative electrode active material layer 12 and the surface of the negative electrode current collector 11 is wide, and it is possible to effectively suppress the peeling of the negative electrode active material layer 12 from the negative electrode current collector 11. ing. Further, the height dimension Ha of the line-shaped pattern 12 from the surface of the negative electrode current collector 11 is smaller than the width dimension Da of the line-shaped pattern 12 (Ha <Da). In this way, by suppressing the height of the line pattern 12, it is possible to more effectively suppress the peeling of the negative electrode active material layer 12 from the negative electrode current collector 11.

The inventors considered the reason why the battery of the present embodiment exhibited good characteristics as follows. As shown in FIG. 5A, a case where an external DC power source Vc is connected to the lithium ion secondary battery module 1 of the present embodiment and a higher potential than the negative electrode current collector 11 is applied to the positive electrode current collector 15 is shown. Think. This state corresponds to the case where the lithium ion secondary battery module 1 is charged by the external DC power supply Vc. At this time, the lithium atoms in the positive electrode active material 14 emit electrons (indicated by “e ⁻ ” in the figure) to become lithium ions (indicated by “Li ⁺ ” in the figure), migrate in the solid electrolyte layer 13. The negative electrode active material layer 12 (line pattern 121) is reached. Then, it recombines with electrons supplied to the negative electrode active material layer 12 through the negative electrode current collector 11. By storing lithium atoms in the negative electrode active material layer 12 in this way, the lithium ion secondary battery module 1 is charged as viewed from the outside.

  In this embodiment, the contact angle θ at the contact point P is smaller than 90 degrees. Therefore, the thickness of the line pattern 121 is extremely small at the contact point P. In particular, in this embodiment, since the negative electrode current collector 11 and the solid electrolyte layer 13 are in contact with each other at the contact point P, the thickness is zero. As the distance from P increases, the thickness increases. Therefore, in the vicinity of the contact point P, the negative electrode current collector 11 and the solid electrolyte layer 13 face each other with the very thin negative electrode active material layer 12 interposed therebetween. For this reason, the distance moved for recombination of lithium ions and electrons in the negative electrode active material layer 12 can be extremely short. On the contrary, the same applies to the discharge in which lithium atoms in the negative electrode active material layer 12 emit electrons. This is considered to contribute to the improvement of charge / discharge characteristics. On the other hand, in the region away from the contact point P, the negative electrode active material layer 12 has a sufficient thickness, so that many lithium atoms can be stored and a large capacity can be obtained. Thus, the lithium ion secondary battery module 1 of the present embodiment can achieve both good charge / discharge characteristics and large capacity.

  In the above-described prior art battery as well, it is considered possible to obtain good charge / discharge characteristics by forming the negative electrode active material layer very thinly, for example, as shown in FIG. However, in such a configuration, since the amount (volume) of the negative electrode active material used is small, the amount of lithium atoms that can be stored is limited, and it is difficult to increase the capacity. Further, as shown in FIG. 5C, the capacity can be increased by increasing the thickness of the negative electrode active material layer. However, when the ground angle θ is 90 degrees or more, ions in the negative electrode active material layer can be increased. In addition, since the distance traveled by the electrons becomes longer, the charge / discharge characteristics are inferior.

  In particular, when the solid electrolyte layer is formed by application of a coating solution containing an electrolyte material, the coating solution does not wrap around the contact point between the negative electrode current collector and the negative electrode active material if the ground angle θ is 90 degrees or more, There is a possibility that a gap is generated at the contact point P. On the other hand, when the grounding angle θ is less than 90 degrees as in this embodiment, the electrolyte material surely goes around the contact point between the negative electrode current collector and the negative electrode active material, and the negative electrode current collector, the negative electrode active material, and The solid electrolytes can be brought into contact with each other at the contact point P, and a battery having excellent characteristics as described above can be obtained.

As described above, in this embodiment, the lithium ion secondary battery in which the negative electrode current collector 11, the negative electrode active material layer 12, the solid electrolyte layer 13, the positive electrode active material layer 14, and the positive electrode current collector 15 are sequentially stacked. In the module 1, Li ₄ Ti ₅ O ₁₂ as a negative electrode active material, polyethylene oxide and polystyrene as a solid electrolyte, and LiCoO ₂ as a positive electrode active material are used as main materials, respectively, and the negative electrode active material layer 12 includes a plurality of line-shaped patterns 121. A striped structure is used. And by making the ground angle θ of the line-shaped pattern 121 with respect to the negative electrode current collector 11 smaller than 90 degrees, it is possible to construct a battery that operates at room temperature, has high capacity, and good charge / discharge characteristics. Yes.

  Here, the line pattern 121 constituting the negative electrode active material layer 12 is obtained by relatively moving the nozzle 31 for discharging the coating liquid containing the negative electrode active material in the Y direction with respect to the surface of the base material (negative electrode current collector 11). It is formed. In such pattern formation by the so-called nozzle scanning method, a large number of parallel line patterns can be formed in a short time with good controllability, and a fine pattern can also be formed. Therefore, a battery having good and stable electrical characteristics can be manufactured with excellent productivity and at a low manufacturing cost.

  Further, by making the surface of the line pattern 121 a smooth curved surface without sharp corners, the degree of adhesion between the negative electrode current collector 11 and the negative electrode active material layer 12 and the solid electrolyte layer 13 can be increased. it can. As a result, it is possible to construct a battery with stable characteristics that is less susceptible to damage such as peeling of these interfaces due to bending of the battery module. As a result, a bendable battery can be constructed, and storage in various shaped containers is facilitated. The application by the nozzle scan method described above is a particularly suitable method for forming the line pattern 121 having such a cross-sectional shape. Note that the structure of the negative electrode active material layer 12 according to the present embodiment is not only for a battery having a solid electrolyte layer, but also for a battery having a liquid electrolyte layer composed of a separator and an electrolytic solution in order to improve its characteristics. Although effective, in this case, it is not an essential requirement to make the surface of the line-shaped pattern 121 a smooth curved surface.

  Further, the negative electrode active material layer 12 in the above embodiment has an island structure in which a plurality of line patterns 121 extending in the Y direction are arranged in the X direction, and each line pattern 121 is independent of the negative electrode current collector. It is formed on the surface of the body 11. However, the “island-like structure” referred to in the present specification is a concept representing that the main part of each pattern exists substantially independently, and not only each pattern is completely independent, A part thereof may be connected as illustrated in FIG.

  FIG. 6 is a diagram illustrating an example of another pattern of the negative electrode active material layer. In the negative electrode active material layer 122 exemplified here, a plurality of line patterns 122a are formed on the surface of the negative electrode current collector 11 and the adjacent line patterns 122a are made of the same material as in the example of FIG. They are connected to each other by a connection part 122b. Even in such a structure, each line-shaped pattern 122a has the same function as the line-shaped pattern 121 in the example of FIG. 1, and it can be said that these have a substantially island-shaped structure. .

  Next, the use of the battery configured as described above will be described. Since the lithium ion secondary battery module 1 of the present embodiment has a high capacity and good charge / discharge characteristics at room temperature, application to various devices is considered as exemplified below. In addition, the following exemplifies a part of the device to which the battery of the present embodiment can be applied, and the scope of application of the battery according to the present invention is not limited to these.

  FIG. 7 is a diagram schematically showing a vehicle, specifically an electric vehicle, as an example of a device equipped with a battery according to the present invention. The electric vehicle 50 includes a wheel 51, a motor 52 that drives the wheel 51, and a battery 53 that supplies electric power to the motor 52. As the battery 53, a configuration in which a large number of the above-described lithium ion secondary battery modules 1 are connected in series and parallel can be employed. The battery 53 configured as described above is suitable as a power source for driving a vehicle such as the electric vehicle 50 because it has a high current supply capability and can be charged in a short time.

  FIG. 8 is a diagram schematically showing an electronic device, specifically, an IC card (smart card) as another example of a device equipped with a battery according to the present invention. The IC card 70 is superposed on each other to form a pair of housings 71 and 72 constituting a card-type package, a circuit module 73 housed in the housing, and a battery 74 serving as a power source for the circuit module 73. And. Among these, the circuit module 73 includes a loop-shaped antenna 731 for communication with the outside, and an integrated circuit (IC) that performs data exchange with the external device via the antenna 731 and various arithmetic / storage processes. Circuit block 732. Further, as the battery 74, a battery provided with one or a plurality of the lithium ion secondary battery modules 1 described above can be used.

  According to such a configuration, the communicable distance with the external device can be extended and more complicated processing can be performed as compared with a general IC card that does not have a power supply. Become. Since the battery 74 according to the present invention is small and thin and has a large capacity, it can be suitably applied to such a card-type device.

  Other than this, machinery such as electric assist bicycles, electric tools, robots, personal computers, mobile phones and portable music players, mobile devices such as digital cameras and video cameras, game machines, portable measuring devices, communication The battery according to the present invention can be employed in various electronic devices such as devices and toys.

  As described above, in the above embodiment, the negative electrode current collector 11 corresponds to the “first current collector layer” of the present invention, and the negative electrode active material layer 12 corresponds to the “first active material layer” of the present invention. The solid electrolyte layer 13 corresponds to the “electrolyte layer” of the present invention, the positive electrode active material layer 14 corresponds to the “second active material layer” of the present invention, and the positive electrode current collector 15 corresponds to the present invention. Corresponds to the “second current collector layer”. Further, steps S101 and S102 in the flowchart of FIG. 2 correspond to the “first step” of the present invention, and steps S103 and S104 correspond to the “second step” of the present invention.

  Further, the electric vehicle 50 in the above embodiment corresponds to a “vehicle” of the present invention. Furthermore, the IC card 70 in the above embodiment corresponds to the “electronic device” of the present invention, and the circuit block 73 functions as the “electronic circuit unit” of the present invention.

  The present invention is not limited to the above-described embodiment, and various modifications other than those described above can be made without departing from the spirit of the present invention. For example, in the above embodiment, the negative electrode active material layer is formed by application by a nozzle scan method, and the solid electrolyte layer is formed by application by a knife coat method or a bar coat method, but the formation method of each layer is limited to these. Instead, various known coating methods can be applied.

  Moreover, in the said embodiment, it is a battery by bonding the laminated body which consists of the positive electrode active material layer and positive electrode collector which were formed separately with respect to the laminated body which consists of a negative electrode collector, a negative electrode active material layer, and a solid electrolyte layer. However, the present invention is not limited to this. For example, a positive electrode active material layer is formed by applying a coating liquid containing a positive electrode active material to a laminate composed of a negative electrode current collector, a negative electrode active material layer, and a solid electrolyte layer. However, a positive electrode current collector may be bonded to this.

  The lithium ion secondary battery according to the present invention can be suitably applied to a vehicle in which the battery is mounted and various electronic devices.

1, 53, 74 Lithium ion secondary battery 11 Copper foil (as negative electrode current collector) 12 Negative electrode active material layer 13 Electrolyte layer 14 Positive electrode active material layer 15 Aluminum foil (as positive electrode current collector) 31 Nozzle 32 Negative electrode active Substance coating solution 50 Electric car (vehicle)
70 IC card (electronic equipment)
71, 72 Card housing (housing)
73 Circuit module (electronic circuit part)
121 Line pattern (of negative electrode active material)

Claims (5)

Having a structure in which a first current collector layer, a first active material layer, an electrolyte layer, a second active material layer, and a second current collector layer are laminated in this order;
The first active material layer has a stripe structure in which a plurality of line-shaped patterns spaced apart from each other are arranged in parallel on the surface of the first current collector layer,
The length dimension of the line-shaped pattern in contact with the surface of the first current collector layer in the longitudinal direction of the line-shaped pattern is the length dimension of the line-shaped pattern in contact with the surface of the first current collector layer in the width direction orthogonal to the longitudinal direction. A lithium ion secondary battery characterized by being at least four times the width of the line pattern.   The lithium ion secondary battery according to claim 1, wherein a height dimension of the line pattern from the surface of the first current collector layer is smaller than the width dimension.   A vehicle comprising the lithium ion secondary battery according to claim 1. The lithium ion secondary battery according to claim 1 or 2,
An electronic device comprising: an electronic circuit unit that operates using the lithium ion secondary battery as a power source. Forming a first active material layer having a stripe structure in which a plurality of line-shaped patterns spaced apart from each other are arranged in parallel on the surface of the first current collector layer;
A second step of laminating an electrolyte layer, a second active material layer, and a second current collector layer in this order on the surface of the first active material layer;
The length dimension of the line-shaped pattern in contact with the surface of the first current collector layer in the longitudinal direction of the line-shaped pattern is the length dimension of the line-shaped pattern in contact with the surface of the first current collector layer in the width direction orthogonal to the longitudinal direction. A method for producing a lithium ion secondary battery, characterized in that it is at least four times the width of the line pattern.

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