Electrode for rechargeable battery, manufacturing apparatus thereof and manufacturing method thereof
A method for manufacturing an electrode for a secondary battery, includes: ejecting, by an ejector, a first slurry and a second slurry at a variable ejection ratio that varies in response to control signals from a controller; coating, by a coater, the first slurry and the second slurry ejected at the variable ejection ratio onto a current collector in a longitudinal direction of the current collector; and drying, by a dryer, the first slurry and the second slurry coated onto the current collector.
1 . A method for manufacturing an electrode for a secondary battery, the method comprising:
ejecting, by an ejector, a first slurry and a second slurry at a variable ejection ratio that varies in response to control signals from a controller;
coating, by a coater, the first slurry and the second slurry ejected at the variable ejection ratio onto a current collector in a longitudinal direction of the current collector; and
drying, by a dryer, the first slurry and the second slurry coated onto the current collector,
wherein thicknesses of the first slurry and the second slurry that are coated onto the current collector vary along a longitudinal direction of the current collector, as the variable ejection ratio of the first slurry to the second slurry varies.
2 . The method as claimed in claim 1 , wherein the ejector comprises a first pump and a second pump, and
wherein to eject the first slurry and the second slurry, the method comprises:
ejecting, by the first pump, the first slurry while rotating at a rotational speed that varies in response to control signals from the controller; and
ejecting, by the second pump, the second slurry while rotating at a rotational speed that varies in response to control signals from the controller.
3 . The method as claimed in claim 2 , wherein in the ejecting of the first slurry and the second slurry, each of a rotational speed of the first pump and a rotational speed of the second pump over time or over a coating length varies in a wave-like manner in response to the control signals from the controller.
4 . The method as claimed in claim 3 , wherein in the ejecting of the first slurry and the second slurry, each of the rotational speed of the first pump and the rotational speed of the second pump over the time or over the coating length varies in a range from ±20% to ±80% based on a central value of the rotational speed.
5 . The method as claimed in claim 1 , wherein the coater comprises a dual-slot die including an upper slot and a lower slot, and
wherein to coat the first slurry and the second slurry, the method comprises:
applying the first slurry onto the current collector through the lower slot of the dual-slot die; and
applying the second slurry onto the current collector through the upper slot of the dual-slot die.
6 . The method as claimed in claim 1 , wherein the coater comprises a slot die including a single slot, and
wherein to coat the first slurry and the second slurry, the method comprises applying the first slurry and the second slurry concurrently onto the current collector through the single slot of the slot die.
7 . The method as claimed in claim 1 , wherein in the ejecting of the first slurry and the second slurry, the variable ejection ratio of the first slurry to the second slurry varies, while a sum of an ejection amount of the first slurry and an ejection amount of the second slurry remains constant, in response to the control signals from the controller.
8 . The method as claimed in claim 1 , wherein to coat the first slurry and the second slurry, the method comprises:
coating the first slurry on a top surface of the current collector; and
coating the second slurry on a top surface of the first slurry.
9 . The method as claimed in claim 8 , wherein a binder content of the first slurry is higher than a binder content of the second slurry.
10 . The method as claimed in claim 1 , further comprising feeding, by a backup roll, the current collector to the coater.
11 . A method for manufacturing an electrode for a secondary battery, the method comprising:
ejecting, by an ejector, a first slurry and a second slurry at a variable ejection ratio that varies in response to control signals from a controller;
coating, by a coater, the first slurry and the second slurry ejected at the variable ejection ratio onto a current collector in a longitudinal direction of the current collector; and
drying, by a dryer, the first slurry and the second slurry coated onto the current collector
wherein in the ejecting of the first slurry and the second slurry, the variable ejection ratio of the first slurry to the second slurry over time or over a coating length varies in a wave-like manner in response to the control signals from the controller.