JP5803829B2 - Electrode manufacturing method - Google Patents

Description

The present invention relates to the production how the electrodes.

  Conventionally, lithium-ion secondary batteries, nickel-hydrogen secondary batteries, and the like are well known as power storage devices mounted on vehicles and the like. In these secondary batteries, an electrode having an active material layer formed on the surface is used.

  As an apparatus for manufacturing such an electrode, a paste-like active material mixture containing an active material and a solvent is applied to a strip-shaped metal foil, and the applied active material mixture is dried while being heated by induction heating. Some are dried by blowing warm air in a furnace (for example, Patent Document 1).

JP 2004-327203 A

  However, in Patent Document 1, when a drying fluid such as warm air is blown onto the metal foil, the metal foil may flutter, and the metal foil may be damaged (broken) by the flaking.

The present invention has been made in view of the problems existing in the prior art, and its object is provide a manufacturing how electrodes can suppress breakage of the metal foil while facilitating the drying of the active material mixture There is to do.

In order to solve the above-mentioned problems, the invention according to claim 1 includes an active material and a solvent applied to the first surface of the metal foil in the electrode manufacturing method in which an active material layer is formed on the surface of the metal foil. A drying step of drying the active material mixture, and in the drying step, fins are formed on the second surface of the metal foil opposite to the first surface and the active material mixture is not applied. In the heat transfer member, the active material mixture is dried in contact with a contact surface opposite to the fin formation surface, and the heat transfer member is made of a composite material containing ceramic particles. The gist is that the ceramic particles are exposed on the contact surface of the heat member .

  According to this, in the drying process, the contact surface of the heat transfer member on which the fins are formed and the second surface where the active material mixture is not applied on the metal foil are in contact with each other. Thus, heat exchange between the metal foil (active material mixture) and a drying fluid such as air is promoted, and along with this, drying of the active material mixture is promoted. For this reason, in a drying process, it can dry, without spraying the fluid for drying on metal foil, or the flow volume of the fluid for drying to spray can be set small. Further, even when a drying fluid is sprayed onto the metal foil, the metal foil and the heat transfer member are in contact with each other, so that the metal foil is prevented from flaking off due to the drying fluid. . Therefore, damage to the metal foil can be suppressed while promoting the drying of the active material mixture.

Further, since the ceramic particles are exposed on the surface of the heat transfer member, the contact surface of the heat transfer member is brought into contact with the second surface where the active material mixture is not applied on the metal foil in the drying step. Thereby, the 2nd surface of metal foil can be processed into a rough surface. Therefore, when an active material mixture is formed on the second surface by forming an active material layer, the active material layer and the metal foil are in close contact with each other without being provided in a separate process for processing the second surface of the metal foil into a rough surface. Can increase the sex.

Invention of Claim 2 is a manufacturing method of the electrode of Claim 1 , In the said drying process, tension | tensile_strength is provided to the direction along the surface of the said metal foil, and the 2nd of the said metal foil by the said tension | tensile_strength. The gist is to bring the surface into close contact with the contact surface of the heat transfer member.

According to this, the 2nd surface of metal foil and the contact surface of a heat-transfer member are closely_contact | adhered, and heat exchange between the metal foil (active material mixture) and the fluid for drying through the heat-transfer member is performed. It can be further promoted.
The invention according to claim 3 is the electrode manufacturing method according to claim 1 or 2 , wherein, in the drying step, a heat medium is circulated through a medium flow path formed between the fins. .

According to this, heat exchange between the heat medium flowing through the medium flow path and the metal foil (active material mixture) can be promoted, and thereby drying of the active material mixture can be promoted .

  According to the present invention, damage to the metal foil can be suppressed while promoting the drying of the active material mixture.

The perspective view which shows a secondary battery typically. The perspective view which shows an electrode assembly typically. (A) And (b) is a schematic diagram of the manufacturing apparatus of an electrode. (A)-(c) is a schematic diagram of a heat-transfer member, (d) is an enlarged view which shows typically the contact surface of metal foil and a heat-transfer member. The flowchart which shows the manufacturing method of a positive electrode sheet and a negative electrode sheet. The schematic diagram of the heat-transfer member in another embodiment. The schematic diagram of the heat-transfer member in another embodiment. (A) And (b) is a schematic diagram of the heat-transfer member in another embodiment.

Hereinafter, an embodiment embodying the present invention will be described with reference to FIGS.
As shown in FIG. 1, a lithium ion secondary battery (hereinafter referred to as “secondary battery”) 10 as a power storage device includes an electrode assembly 12 housed in a metal case 11. The secondary battery 10 of the present embodiment is a prismatic battery whose appearance is square. The case 11 is filled with a nonaqueous electrolytic solution 13 as an electrolyte. A positive electrode terminal 15 and a negative electrode terminal 16 for taking out electricity from the electrode assembly 12 are electrically connected to the electrode assembly 12.

  As shown in FIG. 2, the electrode assembly 12 includes a positive electrode sheet 18 as an electrode, a negative electrode sheet 19 as an electrode, and a separator 20 that insulates between the positive electrode sheet 18 and the negative electrode sheet 19. The electrode assembly 12 is a wound-type electrode assembly configured by winding with a strip-shaped separator 20 interposed between a strip-shaped positive electrode sheet 18 and a strip-shaped negative electrode sheet 19. is there.

  The positive electrode sheet 18 includes a positive electrode metal foil (aluminum foil in this embodiment) 21 and a positive electrode active material layer 22 formed on both surfaces thereof. Further, the portion of the metal foil 21 where the positive electrode active material layer 22 is not formed constitutes the non-coated portion 23. In the electrode assembly 12, a positive electrode current collector 24 in which an uncoated portion 23 is stacked in a direction orthogonal to the winding axis L at one edge of both edges in the direction in which the winding axis L extends. Projectingly formed. The positive electrode current collector 24 is electrically connected to the positive electrode terminal 15.

  Moreover, the negative electrode sheet 19 has the metal foil (in this embodiment copper foil) 25 for negative electrodes, and the negative electrode active material layer 26 formed in the both surfaces. Further, the portion of the metal foil 25 where the negative electrode active material layer 26 is not formed constitutes a non-coated portion 27. And in the electrode assembly 12, the negative electrode current collection part 28 by which the non-coating part 27 was laminated | stacked on the other edge part among the both edge parts of the direction where the winding axis L is extended in the direction orthogonal to the winding axis L. Projectingly formed. The negative electrode current collector 28 is electrically connected to the negative electrode terminal 16.

  Next, the 1st manufacturing apparatus 30 and the 2nd manufacturing apparatus 40 used for manufacture of the positive electrode sheet 18 and the negative electrode sheet 19 are demonstrated according to FIG.3 and FIG.4. The first manufacturing apparatus 30 is an apparatus for forming an active material layer on the first surface M1 which is one side of the metal foils 21 and 25 on which the active material layer is not formed, while the second manufacturing apparatus 40 is In the metal foils 21 and 25 in which the active material layer is formed on the first surface M1, the active material layer is formed on the second surface M2 that is opposite to the first surface M1 and on which the active material layer is not formed. Device.

First, the first manufacturing apparatus 30 will be described.
As shown in FIG. 3A, the first manufacturing apparatus 30 includes a supply mechanism 31 for setting and supplying the strip-shaped metal foils 21 and 25 wound in a roll shape. In addition, an application mechanism unit 33 that applies an active material paste 32 as an active material mixture to the first surface M1 of the supplied metal foils 21 and 25 is provided above the supply mechanism unit 31.

Here, the active material paste 32 applied to the positive electrode metal foil 21 is, for example, LiCoO ₂ as an active material, acetylene black as a conductive agent, polyvinylidene fluoride (PVDF) as a binder, and N-methylpyrrolidone (NMP) as a solvent. A kneaded mixture is used. As the active material paste 32 applied to the metal foil 25 for the negative electrode, for example, a material obtained by kneading carbon as an active material, acetylene black as a conductive agent, PVDF as a binder, and NMP as a solvent is used.

  The coating mechanism 33 includes a tank 33a for storing the active material paste 32, a transfer roller 33b for supporting the active material paste 32 supplied from the tank 33a on the surface, and an active material paste for supporting the active material paste 32 on the surface of the transfer roller 33b. A comma roller 33c for adjusting the thickness (amount) of 32 is provided. In addition, the coating mechanism 33 is provided with a back roller 33d that sandwiches the metal foils 21 and 25 with the transfer roller 33b and rotates and transports the metal foils 21 and 25 in the transport direction Y1.

  The transfer roller 33b rotates in the direction opposite to that of the back roller 33d, thereby transferring and applying the active material paste 32 carried on the surface to the first surface M1 of the metal foils 21 and 25. In addition, in the application | coating mechanism part 33, it is the width | variety in which the non-coating part in which the active material paste 32 is not apply | coated is formed in the both edges of the width direction in the metal foils 21 and 25, and the active material paste 32 is metal foil 21, 25 is applied.

  Further, a drying furnace 34 for drying the active material paste 32 applied to the first surface M1 of the metal foils 21 and 25 is provided on the side of the application mechanism unit 33. Inside the drying furnace 34, a high-temperature heat medium (for example, gas such as air or nitrogen gas) is supplied from the outside to heat the active material paste 32 applied to the metal foils 21 and 25, and at the same time, the active material paste 32. The solvent vapor evaporated from the inside is removed from the drying furnace 34.

  Further, in the drying furnace 34, a heat transfer member 35 for promoting heat exchange between the active material paste 32 applied to the metal foils 21 and 25 and the heat medium flowing in the drying furnace 34 is arranged. It is installed.

  As shown in FIGS. 4A to 4C, the heat transfer member 35 includes a rectangular flat plate-like contact member 36 extending along the conveyance direction Y <b> 1 of the metal foils 21 and 25, and this contact. The upper surface of the member 36 is a contact surface 36a with which the second surfaces M2 of the metal foils 21 and 25 are brought into contact. In the contact member 36, the contact surface 36a is slightly curved upward, and has a convex shape in which the central portion of the metal foils 21 and 25 in the transport direction Y1 protrudes upward.

  In the contact member 36, a plurality of fins 37 each formed in a rectangular flat plate shape on the lower surface opposite to the contact surface 36a are orthogonal to the transport direction Y1 of the metal foils 21 and 25, and the metal foils 21 and 25 It hangs down to extend across the width. The plurality of fins 37 are arranged at equal intervals along the transport direction Y <b> 1 and are formed integrally with the contact member 36. The lower surface of the contact member 36 becomes a formation surface 36b on which the fins 37 are formed.

  In the present embodiment, the aforementioned heat medium is circulated through a medium flow path 37a formed between adjacent fins 37 in the heat transfer member 35 (indicated by an arrow Y2). In the present embodiment, the heating medium is not directly sprayed onto the metal foils 21 and 25 (active material paste 32) in the drying furnace 34. FIG. 4C is a schematic view of the heat transfer member when FIG. 4A is viewed from the cross section in the transport direction.

  The heat transfer member 35 is formed of a composite material of a first material that is a metal and a second material that is a ceramic. In the present embodiment, the metal of the first material is aluminum, and the ceramic of the second material is silicon carbide. The volume ratio of silicon carbide with respect to the heat transfer member 35 is, for example, 60% or more and 90% or less, and preferably 68% or more and 72% or less. The heat transfer member 35 is composed of a silicon carbide powder having a representative particle diameter of 100 μm (median diameter) and a silicon carbide powder having a representative particle diameter (median diameter) of 8 μm in a volume ratio of 7%. : The mixed powder mixed so that it may be set to 3 is used.

  The heat transfer member 35 is manufactured by suction casting in which molten aluminum is sucked and filled with powdered silicon carbide in a mold. The heat transfer member 35 thus formed has a high thermal conductivity of 250 to 340 W / mK, and has a smaller linear expansion coefficient and excellent wear resistance than the case where the heat transfer member 35 is formed from aluminum. . Hard silicon carbide particles are exposed on the surface (contact surface 36 a) of the heat transfer member 35.

  As shown in FIG. 3 (a), on the side of the outlet side of the drying furnace 34, the dried active material paste 32 is transferred by a pair of press rollers 38a while conveying the metal foils 21 and 25 in the conveying direction Y1. A press mechanism 38 that compresses while heating is provided. The positive active material layer 22 or the negative active material layer 26 is completed by compressing the dried active material paste 32 by the press mechanism unit 38.

  Here, the conveyance speed of the metal foils 21 and 25 by the press mechanism part 38 (press roller 38a) is set to a speed very slightly higher than the conveyance speed by the application | coating mechanism part 33 (back roller 33d). For this reason, between the press mechanism part 38 and the application | coating mechanism part 33, tension | tensile_strength is provided to the metal foils 21 and 25 in the direction along the surface of the said metal foils 21 and 25 (conveyance direction Y1). It has become.

  Further, the sandwiching position of the metal foils 21 and 25 by the transfer roller 33b and the back roller 33d and the sandwiching position of the metal foils 21 and 25 by the pair of press rollers 38a are disposed below the contact surface 36a in the heat transfer member 35. ing. For this reason, in the 1st manufacturing apparatus 30, the 2nd surface M2 of the metal foils 21 and 25 and the contact surface 36a of the contact member 36 are closely_contact | adhered by the tension | tensile_strength provided to the metal foils 21 and 25.

And the winding mechanism part 39 which winds up the metal foils 21 and 25 in which the active material layer was formed in the 1st surface M1 in roll shape is provided in the side of the press mechanism part 38. As shown in FIG.
Next, the second manufacturing apparatus 40 will be described.

  The second manufacturing apparatus 40 supplies the metal foils 21 and 25 in which the positive electrode active material layer 22 or the negative electrode active material layer 26 is formed on the first surface M1, and the point that the heat transfer member 35 is not provided in the drying furnace 34. However, since the other configuration is the same as that of the first manufacturing apparatus 30, detailed description thereof is omitted.

  As shown in FIG. 3B, rolls of metal foils 21 and 25 in which an active material layer is formed on the first surface M <b> 1 are set in the supply mechanism unit 31. In the application mechanism unit 33, the active material paste 32 is applied to the second surface M2.

  Instead of the heat transfer member 35, the drying furnace 34 is provided with a plurality of support rollers 41 that support the metal foils 21 and 25 that are transported in the drying furnace 34. In the drying furnace 34, a heat medium is supplied from above the metal foils 21 and 25 so as to be sprayed onto the active material paste 32 applied to the metal foils 21 and 25 (indicated by an arrow Y3).

Next, the manufacturing method of the positive electrode sheet 18 and the negative electrode sheet 19 is demonstrated according to FIG. 5 with the effect | action.
As shown in FIG. 5, first, the application mechanism 33 of the first manufacturing apparatus 30 applies the active material paste 32 to the first surface M1 of the metal foils 21 and 25 where the active material layer is not formed. A coating process is performed (step S1).

  Next, the metal foils 21 and 25 coated with the active material paste 32 are conveyed to the drying furnace 34, and a first drying process is performed as a drying process for drying the active material paste 32 by the drying furnace 34 (step S2). .

  In the first drying step, the drying is performed in a state where the contact surface 36a of the heat transfer member 35 excellent in heat transfer and the second surface M2 of the metal foils 21 and 25 are in contact with each other. Heat exchange with the circulating heat medium is promoted, and along with this, drying of the active material paste 32 is promoted. Further, since the second surface M2 of the metal foils 21 and 25 and the contact surface 36a of the contact member 36 are in close contact with each other by the tension applied to the metal foils 21 and 25, the heat through the heat transfer member 35 is increased. Exchange can be further promoted.

  Moreover, in the drying furnace 34, since the heat medium is circulated through the medium flow path 37a formed between the fins 37, the heat exchange between the heat medium and the metal foils 21 and 25 is promoted, thereby the active material. The drying of the mixture can be promoted. Further, the metal foils 21 and 25 are prevented from flaking due to the circulation of the heat medium.

  And since the metal foils 21 and 25 are conveyed in the state which the 2nd surface M2 and the contact surface 36a closely_contact | adhered, as shown in FIG.4 (d), on the 2nd surface M2 of the metal foils 21 and 25, FIG. A plurality of fine streak-like grooves (scratches) extending along the transport direction Y1 of the metal foils 21 and 25 are formed by ceramic particles (silicon carbide) slightly exposed on the contact surface 36a. As described above, the heat transfer member 35 is made of silicon carbide having a typical particle diameter of 100 μm and silicon carbide having a typical particle diameter of 8 μm. Therefore, the second surface M2 of the metal foils 21 and 25 is formed in a state where a groove having a width corresponding to the surface roughness Ra of 70 to 100 μm and a groove having a width corresponding to the surface roughness Ra of 7 to 10 μm are mixed. .

  Next, as shown in FIG. 5, a first press process is performed in which the dried active material paste 32 is compressed while being heated by the press mechanism unit 38 (step S <b> 3). By this first pressing step, the active material paste 32 is compressed, and the active material layer is completed on the first surface M1 of the metal foils 21 and 25.

  Next, the winding mechanism unit 39 performs a first winding process of winding the metal foils 21 and 25 having the active material layer formed on the first surface M1 in a roll shape (step S4). As described above, in the present embodiment, the first manufacturing apparatus 30 performs each of steps S1 to S4.

  Next, the application mechanism unit 33 of the second manufacturing apparatus 40 applies the active material paste 32 to the second surface M2 opposite to the first surface M1 where the active material layer has already been formed in the metal foils 21 and 25. Two coating processes are performed (step S5).

  Next, a second drying process is performed in which the metal foils 21 and 25 having the active material paste 32 applied to the second surface M2 are conveyed to the drying furnace 34, and the active material paste 32 is dried by the drying furnace 34 (step S6). ). In the second drying step, the active material paste 32 is dried by a drying furnace 34 that does not include the heat transfer member 35. However, in the second drying step, since the active material layer is already formed on the first surface M1 of the metal foils 21 and 25, the strength is improved as compared with the case of the metal foils 21 and 25 alone. For this reason, in a 2nd drying process, even if it heats and sprays a thermal medium on the metal foils 21 and 25 (active material paste 32), possibility that the metal foils 21 and 25 will be damaged is low.

  Next, a second press process is performed in which the dried active material paste 32 is compressed while being heated by the press mechanism unit 38 (step S7). By this second pressing step, the active material paste 32 is compressed, and an active material layer is completed on the second surface M2 of the metal foils 21 and 25. Thereby, the positive electrode sheet 18 or the negative electrode sheet 19 in which the active material layer is formed on both surfaces is completed.

  Thereafter, the winding mechanism unit 39 performs a second winding process in which the metal foils 21 and 25 having the active material layers formed on both surfaces are wound in a roll shape (step S8). As described above, in the present embodiment, steps S5 to S8 are performed by the second manufacturing apparatus 40.

  Thereafter, the completed positive electrode sheet 18 and negative electrode sheet 19 are cut along the length direction at the center in the width direction, and a strip-shaped separator 20 is interposed between the positive electrode sheet 18 and the negative electrode sheet 19. In this state, the electrode assembly 12 is formed. Subsequently, the electrode assembly 12 is accommodated in the case 11 and the current collectors 24 and 28 formed by winding are electrically connected to the terminals 15 and 16, respectively. Then, the secondary battery 10 is completed by filling the case 11 with the nonaqueous electrolytic solution 13.

Therefore, according to the present embodiment, the following effects can be obtained.
(1) In the first drying step (step S2), the contact surface 36a of the heat transfer member 35 and the second surface M2 where the active material paste 32 is not applied on the metal foils 21 and 25 are in contact with each other. Through the heat transfer member 35, heat exchange between the metal foils 21 and 25 (active material paste 32) and the heat medium is promoted, and along with this, drying of the active material paste 32 is promoted. For this reason, in the first drying step, the metal foils 21 and 25 can be dried without spraying a heat medium. Therefore, damage (break) of the metal foils 21 and 25 can be suppressed while promoting the drying of the active material paste 32.

  (2) The heat transfer member 35 is formed of a composite material of aluminum and silicon carbide. For this reason, since hard silicon carbide is exposed on the surface of the heat transfer member 35, the contact surface 36a of the heat transfer member 35 and the second surface M2 of the metal foils 21 and 25 are formed in the first drying step. By making it contact, the 2nd surface M2 of the metal foils 21 and 25 can be processed into a rough surface. Therefore, when forming the active material layer by applying the active material paste 32 to the second surface M2, the active material layer and the metal foil 21, without providing a separate process for processing the second surface M2 into a rough surface. Adhesion with 25 can be improved.

  (3) In the first drying step, tension is applied in the direction along the surfaces of the metal foils 21 and 25, and the second surface M2 and the contact surface 36a of the heat transfer member 35 are brought into close contact with each other by the tension. For this reason, the heat exchange between the metal foils 21 and 25 (active material paste 32) and the heat medium via the heat transfer member 35 can be further promoted.

  (4) In the first drying step, the heat medium is circulated through the medium flow path 37 a formed between the fins 37. For this reason, heat exchange between the heat medium flowing through the medium flow path 37a and the metal foils 21 and 25 (active material paste 32) is promoted, and thereby drying of the active material paste 32 can be promoted.

  (5) In particular, in this embodiment, the heat medium is not directly sprayed on the metal foils 21 and 25 (active material paste 32). For this reason, damage to the metal foil in the first drying step can be further suppressed.

(6) It can suppress that the metal foil 21 which comprises the positive electrode sheet 18 for the secondary batteries 10, and the metal foil 25 which comprises the negative electrode sheet 19 are damaged.
(7) Without providing a large-scale device such as an induction heating device, the drying of the active material paste 32 can be promoted and the cost can be reduced.

The embodiment is not limited to the above, and may be embodied as follows, for example.
The heat transfer member 35 may be formed by a manufacturing method different from various castings using aluminum. For example, as shown in FIG. 6, the heat transfer member 35 bends a rectangular graphite sheet 42 in an inverted U shape, and causes the bent portion 42 a of each graphite sheet 42 to extend along the conveyance direction Y <b> 1 of the metal foils 21 and 25. May be formed side by side. In this case, the contact surface 36a is formed by the upper surface (outer surface) of each bent portion 42a, and the fins 37 are formed by the flat portion depending from each bent portion 42a. The graphite sheet 42 is excellent in heat conductivity in the direction along the surface. Further, the surface of the graphite sheet 42 is smooth and has good slipperiness. For this reason, according to this another example, heat exchange between the metal foils 21 and 25 (active material paste 32) and the heat medium via the heat transfer member 35 can be further promoted, and the contact surface 36a is brought into contact with the heat transfer member 35. The resistance when the metal foils 21 and 25 are conveyed in the state can be reduced.

  As shown in FIG. 7, the heat transfer member 35 may be provided with a heater 43 by casting. Since the heat transfer member 35 is formed by suction casting or high pressure casting, there are few cast holes (voids). For this reason, it is possible to suppress uneven heating of the metal foils 21 and 25 or a burden on the heater 43 due to non-uniform transmission of heat from the heater 43 to the heat transfer member 35. Moreover, since the coefficient of linear expansion of the heat transfer member 35 is small, deformation of the heater 43 due to heating can be suppressed, and the temperature of the heater 43 can be set to a high temperature (for example, 350 to 400 ° C.). And according to this example, drying of the active material paste 32 can be further promoted by the heater 43.

  ○ The shape and number of fins 37 may be changed. For example, as shown in FIG. 8 (a), the fins 37 may be formed in the shape of corrugated ribs, and as shown in FIG. 8 (b), the fins 37 are staggered in the transport direction Y1 of the metal foils 21 and 25. It may be formed. Further, the fin 37 may be an offset fin. Moreover, the fin 37 may be extended along the conveyance direction Y1 of the metal foils 21 and 25.

The heat transfer member 35 may be manufactured by forming the fin 37 and the contact member 36 separately and then joining them.
○ The material constituting the heat transfer member 35 may be changed. For example, the first material can be an aluminum alloy, and the second material can be changed to aluminum oxide or aluminum nitride. The heat transfer member 35 may be formed of a hypereutectic alloy of silicon and aluminum. Even with such a configuration, hard ceramic or silicon can be exposed on the surface of the heat transfer member 35.

The heat transfer member 35 may be formed of aluminum or an aluminum alloy. That is, the heat transfer member 35 should just be formed from the material excellent in heat conductivity.
The heat transfer member 35 may be formed by die casting, molten metal forging, or high pressure casting.

○ The contact surface 36a of the heat transfer member 35 may be formed flat,
The tension | tensile_strength does not need to be provided to the metal foils 21 and 25 between the application | coating mechanism part 33 and the press mechanism part 38. FIG.

  The positive electrode sheet 18 and the negative electrode sheet 19 may be manufactured by applying the active material paste 32 to the first surface M1 of the metal foils 21 and 25 that are not strip-shaped. In this case, in the first drying step (step S2), for example, after applying the active material paste 32 to the first surface M1 of the rectangular metal foils 21 and 25, the metal foils 21 and 25 are placed on the heat transfer member 35. The second surface M2 and the contact surface 36a may be dried in a contacted state.

  In the first drying step, the heat medium may be directly sprayed on the metal foils 21 and 25. Even in this case, since the metal foils 21 and 25 and the heat transfer member 35 are in contact with each other, it is possible to suppress the metal foils 21 and 25 from being fluttered by the heat medium. Therefore, damage to the metal foil can be suppressed while promoting the drying of the active material mixture. Further, if the heat medium is directly sprayed in the first drying step as in the second drying step, the time required for the first drying step may be shorter than that in the second drying step. In that case, the equipment length of the drying furnace 34 in the 1st manufacturing apparatus 30 can be shortened.

A part or all of each press process (steps S3 and S7) and each winding process (steps S4 and S8) may be omitted.
The first manufacturing apparatus 30 and the second manufacturing apparatus 40 may not include all or part of the supply mechanism unit 31, the coating mechanism unit 33, the press mechanism unit 38, and the winding mechanism unit 39.

In the case where the positive electrode active material layer 22 or the negative electrode active material layer 26 is formed only on one surface of the metal foil, the second manufacturing apparatus 40 may not be provided.
○ The secondary battery 10 is formed by punching a positive electrode sheet 18 and a negative electrode sheet 19 into a rectangular shape, and laminating with a separator 20 interposed between the positive electrode sheet 18 and the negative electrode sheet 19. The electrode assembly 12 may be used.

O You may actualize as electrical storage apparatuses, such as a nickel hydride secondary battery and an electrical double layer capacitor, the electrode for the said electrical storage apparatuses, and the manufacturing method of an electrode.
Hereinafter, a technical idea that can be grasped from the above embodiment and another example will be additionally described.

(A) A power storage device having an electrode assembly in which electrodes are stacked with a separator interposed therebetween, wherein the electrode is an electrode manufactured by the above manufacturing method .

  M1 ... first surface, M2 ... second surface, S2 ... step (drying process), 10 ... lithium ion secondary battery (power storage device), 18 ... positive electrode sheet (electrode), 19 ... negative electrode sheet (electrode), 21 ... Metal foil, 22 ... Positive electrode active material layer (active material layer), 25 ... Metal foil, 26 ... Negative electrode active material layer (active material layer), 32 ... Active material paste (active material mixture), 35 ... Heat transfer member, 36a ... contact surface, 36b ... forming surface, 37 ... fin, 37a ... medium flow path, 42 ... graphite sheet, 42a ... bent portion.

Claims (3)

In the manufacturing method of the electrode in which the active material layer is formed on the surface of the metal foil,
Including a drying step of drying an active material mixture containing an active material and a solvent applied to the first surface of the metal foil,
In the drying step,
In the metal foil, a second surface that is opposite to the first surface and not coated with the active material mixture, and a contact that is opposite to the surface on which the fin is formed in the heat transfer member on which the fin is formed. The active material mixture is dried in a state where the surface is contacted ,
The heat transfer member is made of a composite material containing ceramic particles, and the ceramic particles are exposed on the contact surface of the heat transfer member . In the drying step,
The manufacturing method of the electrode of Claim 1 which provides tension | tensile_strength in the direction along the surface of the said metal foil, and adheres the 2nd surface of the said metal foil, and the contact surface of the said heat-transfer member with the said tension | tensile_strength. In the drying step,
The method for manufacturing an electrode according to claim 1 , wherein a heat medium is circulated through a medium flow path formed between the fins.