Crushing method for galvanic cells with high energy densities

Abstract

A crushing method for galvanic cells with high energy densities in which a mixture of used cells is placed inside an insulated container and carbon dioxide as dry ice is added to this mixture as a cooling medium. Dry ice is added to the mixture of used galvanic cells at a volumetric ration of 0.5:1 to 2:1. The mixture of used cells with dry ice is cooled down from ?20? C. to ?50? C. and is subsequently fed to the crushing device and subjected to crushing. A stream of used galvanic cells and a stream of dry ice granules are preferably fed simultaneously to the insulated container of the crushing device, and this mixture is forwarded to the working part of the crushing device. At the end of galvanic cell crushing, the mixture of air and gaseous carbon dioxide is returned to the insulated container.

Claims

1. A method for processing used galvanic cells with high energy densities, comprising: placing a mixture of the used galvanic cells inside an insulated container; adding a cooling medium to the mixture to reduce the temperature of the used galvanic cells; and subsequently feeding the mixture and the cooling medium to a working unit of a crushing device; wherein the cooling medium is carbon dioxide as dry ice; wherein the mixture is cooled down to a temperature of ?20? C. to ?50? C.; and wherein a volumetric ratio of the used galvanic cells to the dry ice is between 0.5:1 and 2:1.

2. The method according to claim 1, wherein said dry ice is a granulate, with granule size of 1 mm to 100 mm.

3. The method according to claim 1, wherein said dry ice is a granulate, with granule size of 14 mm to 18 mm.

4. The method according to claim 1, wherein alternate layers of dry ice and of the used galvanic cells are placed in an insulated container of the crushing device during the placement of the used galvanic cells.

5. The method according to claim 1, wherein a stream of the used galvanic cells and a stream of dry ice granules are fed simultaneously to an insulated container of the crushing device.

6. The method according to claim 1, wherein after the crushing of the used galvanic cells, a mixture of air and carbon dioxide is returned to an insulated container of the crushing device.

7. The method according to claim 6, wherein the mixture of air and carbon dioxide is returned with an average linear rate of 10 m/h to 36 m/h.

Description

DESCRIPTION OF PREFERRED EMBODIMENTS

(1) The subject of the invention is presented below as embodiments.

(2) A mixture of used cells is placed in the insulated container and a cooling medium is added to this mixture, the temperature of used cells is decreased and the cooled mixture of used cells and of the cooling medium is then fed to the working unit of the crushing device. The cooling medium in this embodiment is carbon dioxide in the form of dry ice, added to the mixture of used galvanic cells at a volumetric ratio of 0.5:1. Next, the mixture of used cells and dry ice is cooled to ?20? C., followed by feeding the mixture of used cells and dry ice to the working unit of the crushing device.

(3) Dry ice in this embodiment is a granulate with granule size of 1 mm. In other embodiments, dry ice may be used as granulate with granule size up to 18 mm.

(4) Alternate, 5 cm thick layers of dry ice and used cells are placed in the insulated container of the crushing device during placement of used galvanic cells in the insulated container.

(5) In another embodiment, a stream of used galvanic cells and a stream of dry ice granules are fed simultaneously to the insulated container of the crushing device.

(6) At the end of galvanic cell crushing, the mixture of air and carbon dioxide is returned to the insulated container of the crushing device.

(7) In this embodiment, the mixture of air and carbon dioxide is returned from the crushing zone to the insulated container at an average, linear rate of 10 m/h.

(8) In the next embodiment, a mixture of used cells is placed in the insulated container and a cooling medium is added to this mixture, the temperature of used cells is decreased and the cooled mixture of used cells and of the cooling medium is then fed to the working unit of the crushing device. The cooling medium in the form of dry ice is added to the mixture of used galvanic cells in this embodiment at a volumetric ratio of 2:1, and the mixture of used cells with said dry ice is cooled down to ?50? C., and the mixture of used cells and dry ice is fed to the working unit of the crushing device.

(9) In this embodiment, dry ice is a granulate with granule size of 100 mm. In this embodiment, alternate, 20 cm thick layers of dry ice and 10 cm thick layers of used cells are placed in the insulated container of the crushing device during placement of used galvanic cells in the insulated container.

(10) In this embodiment, the mixture of air and carbon dioxide is returned from the crushing zone to the insulated container at an average, linear rate of 36 m/h.

(11) According to another embodiment of the invention, the mixture of used cells is placed in an insulated container of the crushing device, in this embodiment in a container of a known, double shaft, slow rotation shredder crushing machine with cutting discs with a diameter of 260-360 mm and thickness of 3 to 15 mm. The mixture of used cells of the 18650 and/or 2170 type is simultaneously cooled in this container using recirculated mixture of cold carbon dioxide and air and/or by adding dry ice. In this embodiment, dry ice is added crushed into granules with diameter of 14 mm to 18 mm, in a volumetric ratio to used cells from 1:100 to 1:10. The mixture with dry ice decreases the temperature of recycled cells. The mixture of used cells and dry ice is stored in the thermally insulated container of the crushing device by the technologically required time, usually no longer than 15 minutes, in order to decrease the cell temperature to at least ?20? C. Then, the chute leading from the insulated container to the working unit of the crushing device is opened. Inside the working unit of the double shaft shredder, the initially cooled mixture of used cells is crushed into particles with size between 2 mm and 8 mm with additional dry ice, wherein the material temperature reaches ?20? C. to ?50? C. Such crushed cells are directed to separation and possible further crushing, where the known process of sorting into individual, recoverable fractions takes place.

(12) The mixture of used cells with dry ice is conditioned to the crushing temperature in two stages: inside the insulated container, for 15 minutes, to ?20? C., and during the crushing itself, to between ?30? C. and ?50? C.

(13) In another embodiment of the invention, layers of used galvanic cells are placed inside the insulated container of the crushing device loosely packed, alternating with dry ice layers, in the respective, initial volumetric ratio of 7:1.

(14) After crushing of galvanic cells in the double shaft shredder to fractions listed for this embodiment (the initial volumetric ratio of 7:1), the mixture of air and carbon dioxide is directed to the space of cutting discs of the double shaft shredder and to subsequent operations or unit processes of battery recycling. This mixture is fed from the space of cutting discs of the disc mill to the insulated container at the average linear rate of 20 m/h.