Battery deconstruction apparatus and methods
Apparatus ( 10 ) for safe and effective shredding of batteries, including lithium-ion batteries, is disclosed. The system integrates a shredding subassembly ( 12 ), an auger/screw conveyor subassembly ( 14 ), a rotary screen subassembly ( 16 ), and an optional solvent recovery/recirculation subassembly ( 18 ). Valves/actuators ( 26, 28 ) can be coordinated such that a nitrogen blanket or a vacuum is maintained within the shredding assembly and/or the other subassemblies ( 16, 18 ). Shredded battery materials are transported to the rotary screen subassembly ( 16 ) via the auger-screw conveyor assembly ( 14 ) before being washed and split into solid and liquid sub-components.
1 . Apparatus for recycling batteries containing solid battery materials and liquid electrolyte, comprising:
a shredder subassembly, including a feed hopper having a hopper inlet adapted to receive the batteries to be shredded, an intermediate hopper connected to said feed hopper via a first valve, a shredding chamber connected to said intermediate hopper via a second valve, and at least one shredder at least partially contained in said shredding chamber and configured to shred the solid battery materials into shredded battery materials;
an auger subassembly adapted to receive the shredded battery materials from said shredder subassembly;
a rotary screen subassembly, adapted to receive the shredded battery materials via said auger subassembly, said rotary screen subassembly including a housing having an inlet end proximal to said auger subassembly and an outlet end distal to said auger subassembly, a cylindrical rotary screen provided with a plurality of holes and adapted for rotation via a motor, a plurality of spiral baffles provided along the length of said cylindrical rotary screen, a soaking chamber located in said cylindrical rotary screen proximal to said inlet end of said housing, a plurality of spray nozzles contained within said housing and adapted to discharge solvent in said housing, a discharge duct adapted to receive solvent and liquid electrolyte at said inlet end of said housing and a discharge chute adapted to receive shredded battery materials at said outlet end of said housing;
a solvent recovery/recirculation subassembly, including a collection tank located below and to one side of said rotary screen subassembly, said discharge duct extending from said housing to said collection tank, whereby solvent, liquid electrolyte and shredded battery materials can flow from said rotary screen subassembly to said solvent recovery/recirculation subassembly, baffles provided on said collection tank, adapted to create a centrifugal effect on solvent, liquid electrolyte and shredded battery materials delivered to said collection tank, a waste drain adapted to receive solvent, liquid electrolyte and/or shredded battery materials, a third valve adapted to control flow through said waste drain, a separation area adapted to separate shredded battery materials from solvent, a fourth valve adapted to discharge solvent from said collection tank, and a pump adapted to transport solvent discharged from said fourth valve to said rotary screen subassembly via a recirculation duct for reuse; and
a control system, adapted to coordinate operation of said first valve and said second valve.
2 . The apparatus of claim 1 , wherein said housing is inclined upward such that said outlet end of said housing is higher than said inlet end of said housing.
3 . The apparatus of claim 1 , wherein said spray nozzles are aimed away from said soaking chamber.
4 . The apparatus of claim 1 , wherein said discharge duct connects to said inlet end of said housing to receive built-up liquid from said soaking chamber.
5 . The apparatus of claim 1 , wherein said auger subassembly includes a motorized screw conveyor.
6 . The apparatus of claim 5 , wherein said motorized screw conveyor is angled upward towards said rotary screen subassembly.
7 . The apparatus of claim 1 , wherein said hopper inlet is formed in an upper end of said feed hopper.
8 . The apparatus of claim 1 , wherein said hopper inlet is formed in a side of said feed hopper.
9 . The apparatus of claim 1 , wherein said motor is located at said inlet end of said housing.
10 . The apparatus of claim 1 , wherein said motor is located at said outlet end of said housing.
11 . The apparatus of claim 1 , wherein at least one shredder includes two shredders.
12 . The apparatus of claim 11 , wherein said two shredders include a coarse shredder and a fine shredder.
13 . The apparatus of claim 1 , wherein said shredding chamber is connected to said auger subassembly via a gate valve.
14 . The apparatus of claim 1 , further comprising a liquid bath in which said least one shredder is immersed.
15 . The apparatus of claim 1 , wherein said rotary screen subassembly includes a rotary valve proximal to said outlet end of said housing.
16 . The apparatus of claim 15 , wherein said control system is adapted to maintain a nitrogen blanket or a vacuum between said second valve and said rotary valve.
17 . The apparatus of claim 1 , wherein said shredder subassembly includes a showering means adapted to wash said shredder subassembly with intermittent showers via a series of ports on said shredder subassembly.
18 . The apparatus of claim 1 , wherein said shredder subassembly includes a rotary airlock feeder adapted to control discharge of shredded material from said at least one shredder.
19 . The apparatus of claim 1 , wherein said at least one shredder is configured to work under vacuum, under N 2 or CO 2 blanketing, while completely submerged or with intermittent liquid showers.
20 . The apparatus of claim 1 , wherein said first and second valves are gate valves.
21 . The apparatus of claim 1 , wherein said third valve is a knife gate valve.
22 . The apparatus of claim 1 , wherein said fourth valve is a bleed valve.
23 . The apparatus of claim 1 , wherein said rotary screen subassembly includes an oxygen sensing system, adapted and positioned to monitor an oxygen concentration in said apparatus and configured to shut down said apparatus when excessive oxygen is detected.