Method for recycling electrode scraps, and method for manufacturing electrode by using same
Provided are a reuse method of electrode scrap and a method of fabricating a recycled electrode using the same. The reuse method of electrode scrap of the present disclosure includes (a) dry milling electrode scrap remaining after punching an electrode sheet including an active material layer on a current collector to obtain milled products; and (b) screening active material layer flakes from current collector fragments in the milled products by sieving the milled products, and collecting the screened active material layer flakes to obtain reusable particles.
1. A method of reusing an electrode scrap, comprising:
dry milling an electrode scrap remaining after punching an electrode sheet including an active material layer on a current collector to obtain milled products;
screening active material layer flakes from current collector fragments in the milled products by sieving the milled products to produce screened active material layer flakes; and
collecting the screened active material layer flakes to obtain reusable particles,
wherein
the screening comprises separating the active material layer flakes from the current collector fragments in the milled products stepwise according to size by sieving the milled products in a sequential order using a plurality of sieves having different mesh sizes; and
the collecting comprises collecting smallest sized active material layer flakes and active material layer flakes that are at least one size bigger than the smallest sized active material layer flakes to obtain reusable particles.
2. The method according to claim 1 , wherein the dry milling uses any one of a pin-mill, a disc-mill, a cutting-mill or a hammer-mill.
3. The method according to claim 1 , wherein in the screening,
the plurality of sieves is stacked, wherein each sieve of the plurality of sieves has a mesh size that gradually decreases from top to bottom,
the milled products are fed into an uppermost sieve, and
screening is performed under vibration applied to all the sieves by a vibrating motor.
4. The method according to claim 1 , wherein the method further comprises reusing the smallest sized active material layer flakes and the active material layer flakes that are at least one size bigger than the smallest sized active material layer flakes.
5. The method according to claim 1 , wherein the method comprises, before the dry milling, punching an electrode sheet including an active material layer on a current collector to a predetermined size.
6. The method according to claim 1 , wherein the dry milling is conducted by a pin mill comprising a screen with opening, and the milled products pass through the openings.
7. A method of fabricating a recycled electrode, comprising:
dry milling an electrode scrap remaining after punching an electrode sheet including an active material layer on a current collector to obtain milled products;
screening active material layer flakes from current collector fragments in the milled products by sieving the milled products to produce screened active material layer flakes;
collecting the screened active material layer flakes to obtain reusable particles; and
using the reusable particles alone without composition adjustment, or in combination with a same slurry as a slurry used to form the active material layer to fabricate another electrode,
wherein
the screening comprises separating the active material layer flakes from the current collector fragments in the milled products stepwise according to size by sieving the milled products in a sequential order using a plurality of sieves having different mesh sizes; and
the collecting comprises collecting smallest sized active material layer flakes and active material layer flakes that are at least one size bigger than the smallest sized active material layer flakes to obtain the reusable particles.
8. The method according to claim 7 , wherein the dry milling uses any one of a pin-mill, a disc-mill, a cutting-mill or a hammer-mill.
9. The method according to claim 7 , wherein the dry milling uses a pin-mill with a screen having an opening size of 0.1 to 1.9 mm.
10. The method according to claim 7 , wherein in the screening,
the plurality of sieves is stacked, wherein each sieve of the plurality of sieves has a mesh size that gradually decreases from top to bottom,
the milled products are fed into an uppermost sieve, and
screening is performed under vibration applied to all the sieves by a vibrating motor.
11. The method according to claim 7 , wherein the screening comprises screening the active material layer flakes of more than 0 μm and 100 μm or less to obtain the usable particles.
12. The method according to claim 7 , wherein the method further comprises reusing the smallest sized active material layer flakes and the active material layer flakes that are at least one size bigger than the smallest sized active material layer flakes.