Electrode sheet manufacturing apparatus and power storage device manufacturing method
Provided is an electrode sheet manufacturing apparatus that forms an electrode sheet by cutting a sheet stack including an electrode composite material layer and a separator provided on the electrode composite material layer. The electrode sheet manufacturing apparatus includes a laser irradiation device that irradiates the sheet stack with a first laser beam having a wavelength to be absorbed by the separator and a second laser beam having a wavelength to be absorbed by the electrode composite material layer, and a controller that controls driving of the laser irradiation device. The controller moves an irradiation position of the first laser beam relative to the sheet stack and moves an irradiation position of the second laser beam so as to follow a track of the irradiation position of the first laser beam.
1. A power storage device manufacturing method comprising:
preparing a sheet stack including an electrode composite material layer and a separator provided on the electrode composite material layer;
irradiating the separator of the sheet stack with a first laser beam having a wavelength to be absorbed by the separator, and moving an irradiation position of the first laser beam relative to the sheet stack; and
irradiating the sheet stack having been irradiated with the first laser beam with a second laser beam having a wavelength to be absorbed by the electrode composite material layer, and moving an irradiation position of the second laser beam relative to the sheet stack, wherein
the irradiation position of the second laser beam moves so as to follow a track of the irradiation position of the first laser beam; and
wherein a distance between the irradiation position of the first laser beam and the irradiation position of the second laser beam in a moving direction of the first laser beam in the sheet stack is equal to or larger than a value obtained by multiplying a time from when the separator is irradiated with the first laser beam until when the separator melts and a moving speed of the irradiation position of the second laser beam.
2. The power storage device manufacturing method according to claim 1 , further comprising conveying the sheet stack in a conveying direction, wherein the sheet stack being conveyed in the conveying direction is irradiated with the first laser beam and the second laser beam, and the irradiation position of the first laser beam and the irradiation position of the second laser beam move in the conveying direction as well as in a width direction of the sheet stack.
3. The power storage device manufacturing method according to claim 1 , wherein output power of the second laser beam is higher than output power of the first laser beam.
4. The power storage device manufacturing method according to claim 1 , wherein:
a wavelength of the first laser beam is within a range from 1500 nm to 3000 nm;
a wavelength of the second laser beam is within a range from 300 nm to 2000 nm; and
the wavelength of the first laser beam is longer than the wavelength of the second laser beam.