Magnetism alignment apparatus for negative electrodes and method for manufacturing negative electrodes using same

1 . A magnetic alignment device for a negative electrode having a negative electrode slurry including a carbon-based negative electrode active material disposed on a negative electrode collector of an electrode sheet, the magnetic alignment device comprising:

a first magnet part and a second magnet part spaced away from each other in a vertical direction and configured to accommodate the electrode sheet traveling along a traveling direction therebetween;

a loading amount measuring part arranged prior to the first and second magnet parts along the traveling direction, and configured to measure a loading amount of the negative electrode slurry disposed on the electrode sheet; and

a controller configured to adjust a separation distance of the first magnet part and the second magnet part based on the loading amount;

wherein each of the first and second magnet parts comprise a plurality of unit magnets arranged in a width direction of the negative electrode slurry disposed on the electrode sheet, wherein the plurality of unit magnets in one of the first and second magnet parts is configured to be individually moveable along the vertical direction to adjust the separation distance, so as to magnetically align the plurality of unit magnets of the other one of the first and second magnet parts being centered on the electrode sheet, and

wherein the magnetic alignment device is configured to orient the carbon-based negative electrode active material by applying a magnetic force.

2 . The magnetic alignment device of claim 1 ,

wherein the controller part includes a database storage device configured to store a plurality of reference values of the separation distance, and

wherein the controller part is configured to adjust the separation distance based on the plurality of reference values corresponding to a plurality of loading amounts of the negative electrode slurry measured by the loading amount measuring part.

3 . The magnetic alignment device of claim 1 ,

wherein each of the plurality of unit magnets comprise a support part and a distance adjuster,

wherein the support part accommodates and fixes respective ones of the plurality of unit magnets; and

wherein the distance adjuster is coupled to the support part and configured to move the support part in the vertical direction.

4 . The magnetic alignment device of claim 1 , wherein the separation distance between the first magnet part and the second magnet part is adjustable in a range of 10 mm to 50 mm.

5 . The magnetic alignment device of claim 1 , wherein the first magnet part and the second magnet part comprise ones of the plurality of unit magnets having opposing magnetic poles facing each other.

6 . The magnetic alignment device of claim 1 , wherein the loading amount measuring part comprises at least one of a web gauge or an ultrasonic sensor.

7 . The magnetic alignment device of claim 6 , wherein the ultrasonic sensor comprises:

an ultrasonic generator configured to discharge ultrasonic waves toward a surface of the negative electrode slurry;

an ultrasonic receiver configured to scan the negative electrode slurry and receive the ultrasonic waves; and

a data transmitter programmed to calculate the loading amount of the negative electrode slurry based on data obtained from the ultrasonic sensor and transmit the data to the controller part.

8 . The magnetic alignment device of claim 1 , wherein the magnetic alignment device comprises a dryer configured to dry the negative electrode slurry.

9 . A method of manufacturing a negative electrode, comprising:

applying a negative electrode slurry comprising a carbon-based negative electrode active material on a negative electrode collector;

aligning the carbon-based negative electrode active material using the magnetic alignment device of claim 1 ; and

drying the negative electrode slurry in which the carbon-based negative electrode active material is in an aligned state to form a negative electrode active layer,

wherein the aligning of the carbon-based negative electrode active material comprises adjusting a separation distance between the negative electrode slurry and the first and second magnet parts of the magnetic alignment device based on a loading amount of the negative electrode slurry.

10 . The method for manufacturing the negative electrode of claim 9 , wherein the loading amount of the negative electrode slurry is in a range of 100 mg/25 cm 2 to 500 mg/25 cm 2 .

11 . The method for manufacturing the negative electrode of claim 9 , wherein the negative electrode active layer has an alignment degree (O.I.) of the carbon-based negative electrode active material in a range of 0.1 to 5.0 based on Equation 1:

O

.

I

.

=

I

0

⁢

0

⁢

4

/

I

1

⁢

1

⁢

0

[

Equation

⁢

1

]

I 004 is an area of a peak representing a (0,0,4) crystal face in an X-ray diffraction spectroscopy (XRD) measurement of the negative electrode active layer, and

I 110 is an area of a peak representing a (1,1,0) crystal face in the X-ray diffraction (XRD) measurement of the negative electrode active layer.