Lithium battery recycling methods

Abstract

A method for recycling lithium batteries includes a crushing step of breaking the lithium battery into multiple coarse particles with an average particle size of 1 to 2 cm, a drying step of drying the electrolyte in the coarse particles using a dryer, a primary screening step, first and second magnetic separation steps, and a sorting step. The primary screening step separates multiple sieved powders containing graphite and various metal components, and sieved granules containing iron fragments and plastic particles, through mechanical vibration screening. The first magnetic separation step separates the iron fragments; the second magnetic separation step first separates the magnetic components; and the sorting step separates various recyclable metals according to differences in conductivity at multiple secondary stages, and sorts out valuable powders containing graphite at the primary stage.

Claims

1. A method for recycling a lithium battery, comprising: a crushing step, crushing the lithium battery into multiple coarse particles with an average particle size of 1 to 2 cm; a drying step, drying the electrolyte in the coarse particles using a dryer; a primary screening step, separating multiple sieved powders containing graphite and various metal components through mechanical vibration screening, and leaving screened granules containing iron metal fragments and plastic particles; a first magnetic separation step, screening the screened granules with magnetic force to separate the iron metal fragments; and a rejection step, causing non-magnetic metals in the screened granules to be rejected due to eddy currents generated by electromagnetic induction, thereby leaving the plastic particles. A second magnetic separation step, in which the sieved powder is magnetically sieved to separate the magnetic components; and a sorting step, in which the sieved powder is sorted by eddy currents generated by electromagnetic induction, the sorting step including multiple secondary stages according to the differences in conductivity of various components, in which various recycled metals are sorted in sequence according to the differences in conductivity; and a main stage, in which valuable powder mainly containing graphite is retained.

2. The method for recycling lithium batteries as described in claim 1, wherein, In this crushing step, an inert gas is introduced into the working environment to maintain an oxygen content of less than 6%.

3. The method for recycling lithium batteries as described in claim 1, wherein, This drying step is carried out under a vacuum environment with a vacuum level of less than 1 millibar.

4. The method for recycling lithium batteries as described in claim 1, wherein, In this initial screening step, a vibrating air screen is used.

5. The method for recycling lithium batteries as described in claim 4, wherein, In this initial screening step, an inert gas is introduced into a working environment to maintain an oxygen content of less than 6%.

6. The method for recycling lithium batteries as described in claim 1, wherein, In this sorting step, an inert gas is introduced into a working environment to maintain an oxygen content of less than 6%.

7. A method for recycling lithium batteries as described in any one of claims 2, 5, and 6, wherein, The inert gas is nitrogen.

8. The method for recycling and processing lithium batteries as described in claim 7, wherein, The operating environment is maintained at a slightly positive pressure of slightly more than 1 atmosphere.

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