Electrode paste production device and electrode paste production method

Patent metadata

Field	Value
Publication number	US-9630344-B2
Application number	US-201313974431-A
Country	US
Kind code	B2
Filing date	Aug 23, 2013
Priority date	Sep 6, 2012
Publication date	Apr 25, 2017
Grant date	Apr 25, 2017

Abstract

In production of electrode paste, powder and solvent are separately injected into a hollow exterior component, the powder and the solvent are transferred to a downstream side in a transfer direction by rotation of two rotary shafts supported by the exterior component in a state where the rotary shafts are located parallel to each other at a predetermined interval, a mixture is produced by mixing the powder and the solvent by rotation of the rotary shafts without applying a shearing force, which is higher than or equal to a predetermined shearing force, to the powder, and producing electrode paste by kneading the mixture through application of a shearing force, which is higher than the shearing force that is applied in the mixing step, to the mixture through rotation of the rotary shafts.

First claim

What is claimed is:

1. An electrode paste production device comprising:
a hollow exterior component having a generally tubular configuration while maintaining the same interior cross section throughout its length, and including in said interior, in an axial direction, an injection zone, a rough mixing zone and a kneading zone, the rough mixing zone being located between the injection zone and the kneading zone;
two rotary shafts, the rotation speed of which is controlled by a controller, said shafts located in said interior in an axial direction and extending through the injection zone, rough mixing zone and kneading zone of the exterior component in a state where the rotary shafts are located parallel to each other at a predetermined interval in a direction perpendicular to the axial direction;
the injection zone including a transfer portion in the form of a feed screw configured to transfer separately injected powder and solvent to a downstream side in a transfer direction by rotation of the two rotary shafts;
the rough mixing zone including a rough mixing portion configured to produce a mixture by mixing the powder and the solvent by rotation of the two rotary shafts without applying a shearing force, which is higher than or equal to a predetermined shearing force, to the powder; and
the kneading zone including a kneading portion configured to produce electrode paste by kneading the mixture through application of a shearing force, which is higher than the shearing force that is applied in the rough mixing zone, to the mixture by rotation of the two rotary shafts,
wherein each rotary shaft in the rough mixing portion includes an impeller having a shaft portion and blade portions provided on the outer periphery of the shaft portion radially outward of the rotary shaft, and configured to apply a shearing force to the mixture of the powder and the solvent, and each rotary shaft in the kneading portion includes a paddle configured to apply a higher shearing force to the mixture than the shearing force applied by the impellers of the rough mixing portion, and
wherein a clearance between an outer periphery of a rotational trajectory of the impellers of the rough mixing portion and an inner wall of the housing is larger than a clearance between an outer periphery of a rotational trajectory of the paddles of the kneading portion and the inner wall of the housing.

2. The electrode paste production device according to claim 1 , wherein
a clearance between an outer periphery of a rotational trajectory of the impellers in the rough mixing portion and an inner wall of the exterior component is larger than or equal to 3 mm and smaller than or equal to 10 mm.

3. The electrode paste production device according to claim 1 , wherein
the rotational speed of the two rotating shafts is adjustable to cause an accumulated number of revolutions of each of the rotary shafts in an average residence time of the powder and the solvent in the rough mixing zone to be 300 or larger.

4. The electrode paste production device according to claim 1 , further comprising:
a suppressing portion on a downstream side of the rough mixing portion in the transfer direction in the rough mixing zone, the suppressing portion being configured to suppress by rotation a transfer of the powder and the solvent to the downstream side in the transfer direction, wherein the rotary shafts are located as an upper rotary shaft and a lower rotary shaft, and the suppressing portion includes upper and lower screws supported by the upper and lower rotary shafts, respectively, and oriented in a direction opposite the transfer direction.

5. The electrode paste production device according to claim 1 , wherein the transfer portion includes a powder injection port configured for powder injection and a solvent injection port located downstream of the powder injection port and configured for solvent injection.

6. The electrode paste production device according to claim 1 , wherein the hollow exterior component has such a shape that two perfect circles partially overlap with each other when viewed in the transfer direction, and the rotary shafts are each located at the center of curvature of circular portions of the hollow exterior component.

Assignees

• Kono Takashi
• Toyota Motor Co Ltd

Inventors

• Kono Takashi

Classifications

• B29B7/483

  the other mixing parts being discs perpendicular to the screw axis · CPC title

• B01F3/1221

  Operations & Transport · mapped topic

• B01F7/0065

  Operations & Transport · mapped topic

• B01F7/042

  Operations & Transport · mapped topic

• Y02P70/54

  Cross-Sectional Technologies · mapped topic