JP6519372B2 - Active material mixture kneading method and active material mixture continuous kneader - Google Patents

Description

  The present invention relates to an active material mixture kneading method and an active material mixture continuous kneader for producing an active material mixture for an electrode of a power storage device.

  Power storage devices such as secondary batteries and capacitors can be recharged and can be used repeatedly, and are widely used as a power source. BACKGROUND Conventionally, lithium ion secondary batteries, nickel hydrogen secondary batteries, and the like are well known as power storage devices mounted on vehicles such as EVs (Electric Vehicles) and PHVs (Plug-in Hybrid Vehicles). In these secondary batteries, an electrode having an active material layer formed by applying a paste-like or slurry-like active material mixture containing an active material on the surface of a metal foil to form an active material layer is laminated or interposed with a separator interposed therebetween. The electrode assembly is formed by winding or the like, and the electrode assembly is accommodated in a case.

  The slurry-like electrode active material mixture (hereinafter sometimes referred to simply as electrode mixture) may be prepared by using a raw material containing at least an active material, a binder and a solvent, and optionally containing a conductive auxiliary agent and the like. Knead. The active material, the binder and the conductive aid are powders, and the binder dissolves in the solvent, but the active material and the conductive aid generally do not dissolve in the solvent. Therefore, in order to produce a slurry-like active material mixture by uniformly mixing the raw materials containing the active material, the binder, the conductive auxiliary agent and the solvent, for example, kneading a powder such as the active material with a small amount of solvent ) And then diluting with a solvent. At that time, there is a method of preparing a paste containing a binder and a conductive additive in advance, and kneading the paste and the active material with a twin-screw continuous extruder (bi-screw continuous kneader).

  As shown in FIG. 3, the twin-screw continuous extruder has a material feeding zone 51, a kneading zone 52, a material feeding zone 53 and a dilution zone 54 from the upstream side (left side in FIG. 3) in the feeding direction. Then, the main material (active material) and the paste are continuously supplied from the supply port provided in the material feeding zone 51. The paste means that the solid content is dissolved or dispersed in the solvent, for example, one in which the binder and the conductive auxiliary are dissolved or dispersed in the solvent, or one in which the conductive auxiliary is dispersed in the solvent, There is one in which the binder is dissolved in a solvent. The main material and the paste supplied to the material feeding zone 51 are sent from the material feeding zone 51 to the kneading zone 52, and after being kneaded in the kneading zone 52, the solvent is supplied in the material feeding zone 53 to be fed to the dilution zone 54. The solution is diluted to a predetermined concentration in the dilution zone 54 and discharged as a slurry from the outlet.

  Further, in Patent Document 1, a hollow portion of a barrel which is a hollow member forming an exterior of a biaxial continuous kneader as a biaxial continuous kneader for producing an electrode mixture (a mixture for electrodes) of a battery is a kneading chamber. It has been proposed that the first input part, the solid content part, the second input part, the dilution part, the discharge part and the return part are provided. The first feeding portion is a portion where powder and liquid are supplied to the inside of the barrel, and the first feeding portion is located at the upstream end of the kneading chamber.

  A powder supply port and a first liquid supply port are formed in a portion corresponding to the first input portion of the barrel. The second input portion is adjacent to the solid kneading portion on the downstream side of the solid kneading portion, and a second liquid supply port is formed in a portion corresponding to the second input portion of the barrel, and an electrode mixture is prepared The remaining liquid necessary for (a liquid other than the liquid supplied from the first liquid supply port) is introduced from the second liquid supply port, and the mixture mixed in the solidifying part is diluted in the diluting part.

JP 2012-236159 A

  In the material feeding zone, a paste supply port is disposed adjacent to the main material supply port. However, when a paste of an amount suitable for the active material mixture is added at one time, the adhesion of the mixture is increased, and a part of the main material adheres to the vicinity of the supply port. Thereafter, when adhesion is intermittently released, the main material falls into the mixture. As a result, the amount of main material sent to the kneading zone fluctuates, and the composition of the mixture becomes unstable.

  In the kneader of Patent Document 1, the liquid is introduced twice from the first liquid supply port and the second liquid supply port provided in the kneading chamber. However, the second liquid supply port is a liquid for diluting the mixture mixed in the solidifying part in the diluting part. That is, also in the kneader of Patent Document 1, the liquid containing the binder necessary for kneading the main material constituting the active material mixture and the binder before being sent to the dilution part is one of the first liquid supply ports. The above-mentioned problems occur because it is introduced from the place.

  The present invention has been made in view of the above problems, and an object thereof is to knead an active material mixture which can knead a paste containing a binder and a conductive additive and an active material with a stable composition. A method and an active material combination are to provide a continuous kneader.

  The active material mixture kneading method for solving the above problems comprises: active material mixture kneading having a material feeding step, a kneading step performed after the material feeding step, and a dilution step of charging a solvent into the mixture after the kneading step In the method, the main material is supplied in the material feeding step, and the paste containing at least one of the binder and the conductive auxiliary is supplied from the first step of the material feeding step and the kneading step from the material feeding step. At least a second injection between Here, the "main material" means a main component of the active material mixture, which is mainly an active material. In addition, “paste” means one in which solid content is dissolved or dispersed in a solvent, for example, one in which a binder and a conductive auxiliary are dissolved or dispersed in a solvent, or a conductive auxiliary is dispersed in a solvent And those in which the binder is dissolved or dispersed in a solvent.

  When the main material supplied to the material feeding process and the paste are mixed and sent to the kneading process, if the entire paste is supplied at one time, the proportion of the binder in the mixture to be sent is large near the feed port of the main material. As a result, the adhesion of the main material to the vicinity of the main material supply port increases. Then, after a part is in the state of adhering to the vicinity of the supply port, the adhesion is canceled intermittently, and the unmixed main material falls into the mixture.

  However, in the configuration of the present invention, the ratio of the binder to the main material in the vicinity of the main material supply port is reduced because the paste supply is not performed once in the material feeding process but at least once in addition to that one time. be able to. Therefore, after a part of the main material adheres to the vicinity of the supply port, the adhesion is intermittently eliminated, and the non-mixed main material is prevented from falling into the mixture. Therefore, it is possible to knead the paste containing the binder and the conductive additive and the active material with a stable composition.

  It is preferable that the supply of the paste is performed in the material feeding step and the kneading step. Although the supply of the paste containing the binder may be carried out only in the material feeding step, if the interval between the two feedings of the paste is too short, the effect of dividing into two will be insufficient. The process needs to be lengthened, and the apparatus becomes larger. However, if the paste supply is performed in the material feeding step and the kneading step, the paste can be supplied at least twice without increasing the size of the apparatus.

  It is preferable that the supply amount of the paste supplied in the kneading step is half or less of the supply amount of the paste supplied in the material feeding step. If the amount of paste supplied to be mixed with the main material supplied from the main material supply port in the material feeding step is too small, the amount of binder supplied in the kneading step increases and the binder becomes the main material It is not preferable because uniform mixing becomes difficult. Therefore, the amount of paste supplied in the kneading step is preferably half or less of the supply amount of paste supplied in the material feeding step.

  The paste supply may be performed twice in the material feeding process. The main material and paste supplied to the material feeding process are mixed while moving the material feeding process, but the main material and paste are positively mixed and kneaded while passing through the kneading process and are well mixed. Be done. Therefore, when the paste supply is performed twice in the material feeding process, the main material and the paste supplied are all well passed through the kneading process, so that the mixing is performed well.

  The paste preferably contains a binder and a conductive additive. The active material combination requires a conduction aid depending on the type of active material. The paste containing the conductive auxiliary and the paste containing the binder may be separately prepared and mixed with the main component, but it is preferable to mix the paste containing the binder and the conductive auxiliary with the main component, It is easy to mix the binder and the conductive additive uniformly.

  An active material mixture continuous kneader solving the above problems is an active material mixture continuous kneader having a material feeding zone and a kneading zone provided downstream of the material feeding zone, wherein the material feeding zone And a first paste supply port capable of supplying paste simultaneously with the main material supplied from the main material supply port to the material feed zone, the main material supply port of the material transfer zone A second paste supply port is provided on at least one of the downstream side of the mouth and the kneading zone. This active material mixture continuous kneader can knead the paste containing the binder and the conductive additive and the active material with a stable composition.

  The second paste supply port is preferably provided in the kneading zone. According to this configuration, unlike the case where the first paste supply port and the second paste supply port are provided in the material feeding zone, it is not necessary to lengthen the material feeding zone, and it is not necessary to enlarge the apparatus.

  The kneading zone preferably includes a plurality of paddles, and the second paste supply port is preferably separated from the material feeding zone by one or more paddles. According to this configuration, regardless of the distance between the first paste supply port and the second paste supply port, the backflow of paste to the material feeding zone is prevented.

  According to the present invention, it is possible to knead the paste containing the binder and the conductive additive and the active material with a stable composition.

BRIEF DESCRIPTION OF THE DRAWINGS (a) is a schematic cross section of the biaxial continuous kneader of 1st Embodiment, (b) is sectional drawing in the BB line | wire of (a). FIG. 7 is a partial schematic cross-sectional view of a biaxial continuous kneader of a second embodiment. The schematic diagram which shows the kneading method of a prior art.

First Embodiment
Hereinafter, a first embodiment of the present invention, which is embodied to manufacture an active material mixture for an electrode of a secondary battery as a power storage device, will be described according to FIGS. 1 (a) and 1 (b).

  As shown in FIGS. 1 (a) and 1 (b), a twin-screw continuous kneader as an active material mixture continuous kneader has two rotating shafts 11, 12 along the longitudinal direction of a barrel (cylinder) 10. It is provided in parallel. Both rotary shafts 11 and 12 are rotationally driven in the same direction by a driving device (not shown).

  As shown in FIG. 1 (b), in the space portion S for accommodating the rotating shafts 11 and 12 provided in the barrel 10, when viewed from the axial direction of the rotating shafts 11 and 12, two perfect circles partially overlap each other Have a cross-sectional shape.

  As shown in FIG. 1A, the barrel 10 has a material feeding zone Z1a and a material feeding zone Z1a from the upstream side to the downstream side in the transport direction (direction from left to right in FIG. 1A). It has a kneading zone Z2 provided further downstream, and a dilution zone Z3 provided downstream of the kneading zone Z2. In this embodiment, a material feed zone Z1b is also provided between the kneading zone Z2 and the dilution zone Z3.

  As shown in FIG. 1A, a screw 13a is provided at a position corresponding to the material feeding zone Z1a, and a screw 13b is provided at a position corresponding to the material feeding zone Z1b. The barrel 10 has a main material supply port 14 at a position corresponding to the upstream end of the material feeding zone Z1a, and has a first paste supply port 15 near the main material supply port 14. The main material supply port 14 is a supply port for supplying a powdery main material having an active material as a main component. The first paste supply port 15 is provided so as to be able to supply paste simultaneously with the main material supplied from the main material supply port 14 to the material feeding zone Z1a, and is formed in a smaller hole than the main material supply port 14.

  A powdery main material (active material) is continuously supplied from the main material supply port (not shown) from the main material supply port 14 in a constant amount by a predetermined amount, and a paste is not supplied from the first paste supply port 15. It is continuously supplied so that the ratio from the part to the main material becomes a preset constant ratio.

  Although not shown, a screw similar to the screw 13a provided on the rotating shaft 11 is also provided on the rotating shaft 12, and the screws 13a of both rotating shafts 11 and 12 are supplied from the main material supply port 14. The paste supplied from the main material and the first paste supply port 15 is sent to the kneading zone Z2 by the rotation of the rotating shafts 11 and 12.

  As shown to Fig.1 (a), the several paddle (kneading blade | wing) 16a is provided in the position corresponding to kneading | mixing zone Z2 at predetermined intervals at the rotating shaft 11. As shown in FIG. The barrel 10 has a second paste supply port 17 at a position corresponding to the upstream end of the kneading zone Z2. In the present embodiment, the second paste supply port 17 is disposed at a position separating the paddle 16a by one sheet between the material feeding zone Z1a, but even if the paddle 16a is separated by two or more sheets Good.

  As shown in FIG. 1 (b), a plurality of paddles 16b are provided on the rotary shaft 12 at positions corresponding to the kneading zone Z2 at predetermined intervals. The paddles 16a and 16b rotate with the rotary shafts 11 and 12 and serve to stir and mix the main material and the paste sent to the kneading zone Z2. The paddles 16a and 16b disposed at opposing positions in the longitudinal direction of the rotating shafts 11 and 12 have a substantially triangular shape when viewed from the axial direction of the rotating shafts 11 and 12, and the main components are the same as the paddles 16a and 16b rotate. The material and the paste are stirred and mixed in the space portion S of the barrel 10.

  As shown in FIG. 1A, the rotation shaft 11 is provided with a screw 13b at a position corresponding to the material feeding zone Z1b. The barrel 10 has a solvent inlet 18 at a position corresponding to the material feeding zone Z1b. Although not shown, a screw is similarly provided on the rotary shaft 12 at a position corresponding to the material feeding zone Z1b.

  As shown in FIG. 1A, on the rotating shaft 11, a plurality of paddles 19 are provided at predetermined intervals at positions corresponding to the dilution zone Z3. The paddle 19 has the same configuration as the paddle 16a provided at a position corresponding to the kneading zone Z2. The barrel 10 has an outlet 20 at a position corresponding to the dilution zone Z3. Although not shown, a plurality of paddles are also provided at predetermined intervals on the rotation shaft 12 at positions corresponding to the dilution zone Z3.

Next, the operation of the twin-screw continuous kneader configured as described above will be described.
When manufacturing the active material mixture, the main material supply port 14 of the main material supply port 14 is provided with a predetermined amount of main material of powder from the main material supply portion in a state in which both rotating shafts 11 and 12 are rotated synchronously in the same direction. It is continuously supplied, and the paste is continuously supplied to the first paste supply port 15 so that the ratio to the main material is a predetermined constant ratio. In this embodiment, a paste in which a binder and a conductive additive are dissolved or dispersed in a solvent is used. As the binder, for example, polyvinylidene fluoride (PVDF) is used, and as the solvent, for example, N-methylpyrrolidone (NMP) is used.

  The amount of paste supplied from the second paste supply port 17 is equal to or less than half the amount of paste supplied from the first paste supply port 15. That is, the amount of paste supplied in the kneading zone Z2 is equal to or less than half of the amount of paste supplied in the material feeding zone Z1a. In this embodiment, the ratio of the amount of paste supplied from the first paste supply port 15 to the amount of paste supplied from the second paste supply port 17 is 3: 1.

  As in the conventional kneading method, when the paste containing the binder and the conductive auxiliary supplied to the material feeding zone Z1a is supplied from one supply port adjacent to the main material supply port 14, the vicinity of the main material supply port 14 is obtained. In the above, the adhesion of the mixture of the main component and the paste becomes strong. For this reason, after the mixture, or the mixture and part of the main material adhere to the vicinity of the main material supply port 14, the adhesion is canceled intermittently and the main material not mixed is contained in the mixture. Or fall. As a result, the composition of the mixture sent to the dilution zone Z3 becomes unstable. In addition, when the proportion of the paste, in particular the solvent, increases, it is difficult for the paste to enter the kneading zone with a high filling rate, the back flow and the like easily occur, and the productivity is deteriorated.

  However, in this embodiment, the paste containing the binder and the conductive additive is supplied from the first paste supply port 15 so that all is mixed with the main material supplied from the main material supply port 14 in the material feeding zone Z1a. Instead, a portion of the paste is supplied from the second paste supply port 17 to the kneading zone Z2 so as to be mixed with the mixture sent to the kneading zone Z2. Therefore, the ratio of the binder to the mixture of the main material and the paste supplied to the material feeding zone Z1a decreases, and the mixture is smoothly sent to the kneading zone Z2, and the mixture flows backward or a part of the main material supply port. After being in the state of adhering in the vicinity of 14, the adhesion is canceled intermittently and the main material not mixed is prevented from dropping into the mixture.

  If the amount of paste supplied from the first paste supply port 15 is too small to be mixed with the main material supplied from the main material supply port 14 in the material feeding zone Z1a, the paste is difficult to be uniformly mixed with the main material Is not preferable because However, the amount of paste supplied in the kneading zone Z2 is less than half the amount of paste supplied in the material feed zone Z1a, so the amount of paste supplied from the first paste supply port 15 is too small. However, the paste and the main material are uniformly mixed.

  The main material and the paste sent from the material feeding zone Z1a to the kneading zone Z2 are mixed (kneaded) by rotation of the paddles 16a and 16b in the kneading zone Z2. In the kneading zone Z2, the remaining paste is supplied from the second paste supply port 17, and is kneaded such that the mixing ratio of the main material and the paste becomes the mixing ratio in the active material mixture set in advance. The main material and paste kneaded in the kneading zone Z2 are fed to the dilution zone Z3 through the material feeding zone Z1b.

  Although the filling factor in the kneading zone Z2, that is, the amount of the mixture in the space S is higher than the filling factor in the material feeding zone Z1a, the filling factor is high, so the mixture fed from the material feeding zone Z1a is pushed downstream It moves and adheres on the way such as near the second paste supply port 17 and does not clog.

  As described above, the active material mixture kneading method using the twin-screw continuous kneader includes the material feeding process (material feeding zone Z1a), the kneading process (mixing zone Z2) provided downstream of the material feeding process, and the kneading And a dilution step (dilution zone Z3) provided downstream of the step. Then, the main material is supplied in the material feeding step, and the paste containing the binder and the conductive additive is supplied at one time of the material feeding step and at least once between the material feeding step and the kneading step. That is, since the paste is supplied in the material feeding step and the kneading step, the paste can be supplied at least twice without increasing the size of the apparatus.

According to this embodiment, the following effects can be obtained.
(1) The active material mixture kneading method has a material feeding step, a kneading step performed after the material feeding step, and a dilution step of charging a solvent into the mixture after the kneading step. Then, the main material is supplied in the material feeding step, and the paste containing at least one of the binder and the conductive auxiliary is supplied at least for the first time of the material feeding step and at least the second time between the material feeding step and the kneading step. It takes place by

  In this configuration, the main material in the vicinity of the main material supply port 14 is provided because the paste containing the binder and the conductive auxiliary is not only supplied once but also at least one other time. The ratio of the binder to the binder can be reduced as compared with the case where the paste is supplied only once. Therefore, after a part of the main material adheres to the vicinity of the main material supply port 14, the adhesion is intermittently canceled and the non-mixed main material is prevented from falling into the mixture. Be done. Therefore, it is possible to knead the paste containing the binder and the conductive member and the active material with a stable composition.

  (2) The paste supply is performed in the material feeding step and the kneading step. Although the supply of the paste containing the binder may be carried out only in the material feeding step, if the interval between the two feedings of the paste is too short, the effect of dividing into two will be insufficient. The process needs to be lengthened, and as the apparatus, the material feeding zone becomes long and becomes large. However, if the paste supply is performed in the material feeding step and the kneading step, there is no need to upsize the apparatus. The filling rate of the kneading zone in which the kneading step is performed is high, and the backflow of the paste to the material feeding zone is prevented regardless of the distance between the feeding ports. Further, by separating the second paste supply port 17 in the kneading step from the material feeding step with one or a plurality of paddles 16a, the backflow of the paste to the material feeding step is more reliably prevented.

  (3) The feed rate of the paste fed in the kneading step is half or less of the feed rate of the paste fed in the material feeding step. If the amount of paste supplied so as to be mixed with the main material supplied from the main material supply port 14 in the material feeding step is too small, the amount of binder supplied in the kneading step increases and the binder becomes the main material It becomes difficult to be mixed uniformly. However, the amount of paste supplied in the kneading step is not more than half the amount supplied of the paste supplied in the material feeding step, so the amount of paste supplied from the first paste supply port 15 is never too small. The paste and the main material are uniformly mixed.

  (4) The paste contains a binder and a conductive additive. The paste containing the conductive auxiliary and the paste containing the binder may be separately prepared and mixed with the main component, but it is preferable to mix the paste containing the binder and the conductive auxiliary with the main component, It is easy to mix the binder and the conductive additive uniformly.

  (5) The twin-screw continuous kneader (active material mixture continuous kneader) is provided downstream of the material feeding zone Z1a, the kneading zone Z2 provided downstream of the material feeding zone Z1a, and the kneading zone Z2 And the dilution zone Z3. The material feed zone Z1a has the main material supply port 14, and the material feed zone Z1a has the first paste supply port 15 capable of supplying the paste simultaneously with the main material supplied from the main material feed port 14; A second paste supply port 17 is provided downstream of the main material supply port 14 of the feed zone Z1a and / or at least one of the kneading zone Z2. Therefore, it is possible to knead the paste containing the binder and the active material with a stable composition and in a state in which the deterioration of productivity is prevented.

  (6) The second paste supply port 17 is provided in the kneading zone Z2. Therefore, unlike the case where the second paste supply port 17 is provided in the material feeding zone Z1a, there is no need to lengthen the material feeding zone Z1a, and it is not necessary to enlarge the apparatus.

  (7) The kneading zone Z2 includes a plurality of paddles 16a and 16b, and the second paste supply port 17 is separated from the material feeding zone Z1a by one or more paddles 16a and 16b. According to this configuration, regardless of the distance between the first paste supply port 15 and the second paste supply port 17, the backflow of the paste to the material feeding zone Z1a is prevented.

Second Embodiment
Next, a second embodiment will be described according to FIG. In the second embodiment, the paste is supplied at two points in the material feeding zone Z1a, and the configuration of the material feeding zone Z1a and the kneading zone Z2 is the first embodiment as the constitution of the twin-screw continuous kneader. However, the configurations of the material feed zone Z1b and the dilution zone Z3 are the same. The same parts as those of the first embodiment are denoted by the same reference numerals and the detailed description thereof is omitted.

  As shown in FIG. 2, the second paste supply port 17 is not provided in the kneading zone Z2, and the second paste supply port 17 is provided in the material feed zone Z1a in addition to the first paste supply port 15. ing. If the distance between the first paste supply port 15 and the second paste supply port 17 is too short, the effect of dividing the supply port for supplying the paste into two parts becomes insufficient. Therefore, the material feeding zone Z1a is made longer than the device of the first embodiment. The distance between the first paste supply port 15 and the second paste supply port 17 is preferably, for example, five or more turns of the spiral of the screw 13a.

  The main material and paste supplied to the material feeding zone Z1a are mixed also while moving the material feeding zone Z1a, but are positively kneadable by the paddles 16a and 16b while passing through the kneading zone Z2. Mix well. Therefore, when the paste is supplied at two places in the material feeding zone Z1a, the supplied main material and paste all pass through the kneading zone Z2, so that the mixing is performed well and the quality of the slurry is improved. Becomes stable.

The embodiment is not limited to the above, and may be embodied as follows, for example.
○ The paste containing both the binder and the conductive additive is supplied from the paste supplied from the first paste supply port 15 provided in the material feeding zone Z1a and the second paste supply port 17 provided in the kneading Z2 zone The proportions of the components, that is, the proportions of the binder, the conductive additive, and the solvent may differ depending on the paste to be used.

  The paste supplied from the first paste supply port 15 and the second paste supply port 17 is not limited to one containing a binder and a conductive additive in a solvent. For example, a paste composed of a solvent, a binder and a conductive additive, and a paste composed of a solvent and a binder, or a paste composed of a solvent, a binder and a conductive additive, and a solvent and a conductive additive Alternatively, one paste may be supplied from the first paste supply port 15 and the other paste may be supplied from the second paste supply port 17 using the above paste.

  ○ One paste is supplied from the first paste supply port 15 using the paste composed of the solvent and the binder and the paste composed of the solvent and the conductive additive as the paste, and the other paste is the second paste It may be supplied from the supply port 17.

The first paste supply port 15 may be provided not only on the downstream side of the main material supply port 14 but also on the upstream side of the main material supply port 14.
The binder may be supplied from the main material supply port 14 together with the main material in the form of powder without being supplied as a paste from the main material supply port 14, and the paste may have a conductive auxiliary agent dispersed in a solvent.

  ○ A part of the binder may be supplied in the form of powder, and the remaining binder may be supplied as a paste. In this case, the paste supplied from the first paste supply port 15 and the second paste supply port 17 is composed of a binder, a conductive additive and a solvent, a conductive additive and a solvent, and a binder And a solvent.

○ A solvent may be used in which a dispersion aid is dissolved.
The total number of paste supply ports, that is, the total number of first paste supply ports 15 and second paste supply ports 17 is not limited to two, and may be three or more. For example, the second paste supply port 17 may be provided in both the material feeding zone Z1a and the kneading zone Z2.

  The twin-screw continuous kneader according to the embodiment performs the kneading step and the dilution step in one unit, but can be applied to the case where the kneading step and the dilution step are performed in different devices. For example, in a twin-screw continuous kneader, it is possible to perform up to the kneading step (solid kneading) and to carry out the dilution step with another device, for example, a batch kneader.

  The storage device is not limited to the secondary battery, and may be, for example, a capacitor such as an electric double layer capacitor or a lithium ion capacitor.

  Z1a, Z1b ... material feeding zone, Z2 ... kneading zone, Z3 ... dilution zone, 14 ... main material supply port, 15 ... first paste supply port, 17 ... second paste supply port.

Claims (8)

An active material mixture kneading method comprising a material feeding step, a kneading step performed after the material feeding step, and a dilution step of charging a solvent into the mixture after the kneading step,
The main material is supplied in the material feeding step, and the paste containing at least one of the binder and the conductive additive is supplied at least between the first time of the material feeding step and the material feeding step to the kneading step. A method of mixing and kneading an active material mixture, characterized in that it is performed in a second time.   The active material mixture kneading method according to claim 1, wherein the paste is supplied in the material feeding step and the kneading step.   The active material mixture kneading method according to claim 2, wherein a supply amount of the paste supplied in the kneading step is half or less of a supply amount of the paste supplied in the material feeding step.   The active material mixture kneading method according to claim 1, wherein the paste is supplied at two places in the material feeding step.   The active material mixture kneading method according to any one of claims 1 to 4, wherein the paste contains a binder and a conductive additive. An active material mixture continuous kneader having a material feeding zone and a kneading zone provided downstream of the material feeding zone, wherein
The material feed zone has a main material supply port, and the material feed zone has a first paste supply port capable of supplying paste simultaneously with the main material supplied from the main material feed port; An active material mixture continuous kneader having a second paste supply port at least one of the downstream side of the main material supply port and the kneading zone.   The active material mixture continuous kneader according to claim 6, wherein the second paste supply port is provided in the kneading zone.   The active material mixture continuous kneader according to claim 7, wherein the kneading zone comprises a plurality of paddles, and the second paste supply port is separated from the material feeding zone by one or more paddles. .