Claims:
1. A method for recovery of active materials and current collector materials of electrodes of a battery comprises the steps of:
discharging, the battery in a discharging device (202);
conveying, the discharged battery to a dismantling device (204);
dismantling, the discharged battery, in a dismantling device (204) for separating the battery casing and electrodes of the battery;
sorting the separated battery casing and electrodes of the battery conveyed to a sorting device (206) for further segregating the electrodes of the battery into cathode and anode.;
soaking the segregated cathode and anode conveyed to respective solvent tanks (208,210) for a pre-determined time to weaken the bond between the active material and current collector material of their respective electrodes;
agitating the soaked electrodes (cathode and anode) conveyed to their respective agitator tanks (216,218) with a pre-determined solvent to separate the active materials and current collector materials from their respective electrodes;
removing, the separated current collector materials of their electrodes from the respective agitator tanks (216,218); and
sieving, the solvent of the agitator tanks (216,218) for recovery of the active materials.

2. The method for recovery of active materials from current collector materials of their electrodes of a battery as claimed in claim 1, wherein discharging of the battery is configured to be carried out in brine solution to abstain explosion, fire and toxic gas emission during recovery of active materials and current collector materials of respective electrodes of the battery.

3. The method for recovery of active materials and current collector materials of electrodes of a battery as claimed in claim 1, wherein said segregated electrodes (cathode and anode) are configured to be conveyed in sieve trays (212,214) in the respective solvent tanks (208,210) and the respective agitator tanks (216 ,218) for easy handling and removal of the current collector materials of electrodes of the battery.
4. The method for recovery of active materials and current collector materials of electrodes of a battery as claimed in claim 1, wherein said number of batteries are configured to be processed in agitator tanks (216,218) is based upon the saturation capacity of the pre-determined solvent.( not clear)

5. The method for recovery of active materials and current collector materials of electrodes of a battery as claimed in claim 1, wherein said pre-determined solvent used in the respective solvent tanks (208,210) is from at least one of the group of acetic acid, acetone or ethyl formate.

6. The method for recovery of active materials and current collector materials of electrodes of a battery as claimed in claim 1, wherein said agitator tanks (216,218) are configured with water for weakening the binder material ,binding the active materials on current collector materials of the respective electrodes.

7. The method for recovery of active materials and current collector materials of electrodes of a battery as claimed in claim 1, wherein said separated current collector materials of electrodes trapped in sieve ( 212, 214) , mounted in the respective agitator tanks (216,218) are recovered in its original form for its reuse in manufacturing of new batteries.

8. The method for recovery of active materials and current collector materials of electrodes of a battery as claimed in claim 1, wherein said battery is immersed in 5% NaCl solution for a period of 24 hours in order to discharge the battery to a lower voltage.

9. The method for recovery of active materials and current collector materials of electrodes of a battery as claimed in claim 1, wherein said agitators (220, 222) mounted in the first agitator tank 216 and the second agitator tank 218 respectively are kept idle and not operated for a pre-defined time of 15 minutes and then the agitators (220, 222) are operated for a pre-defined time for recovery of the active materials from the current collector materials of cathode and the anode.

10. A system (200) for recovery of active materials and current collector materials of electrodes of a battery comprises:
a discharging device (202), configured to discharge the battery;
a dismantling device (204), configured to receive the discharged battery conveyed from the discharging device (202) for separating battery casing and electrodes of the battery;
a sorting device (206), configured to receive separated battery casing and electrodes of the battery conveyed from the dismantling device (204), for segregating the electrodes into cathode and anodes of the battery;
a plurality of solvent tanks (208,210) comprising a pre-determined solvent, configured to receive the segregated electrodes conveyed from the sorting device (206) for weakening the bond of the binder material binding the active materials to current collector materials of the respective electrodes; and
a plurality of agitator tanks (216,218) comprising water, configured to receive the soaked electrodes for separating and recovering the active materials from current collector materials of the respective electrodes.

11. The system (200) for recovery of active materials and current collector materials of electrodes of a battery as claimed in claim 10, wherein said discharging device (202) is configured for stabilization of the battery in a brine solution to abstain explosion, fire and toxic gas emission during recovery of active materials and current collector materials of the respective electrodes of the battery.

12. The system (200) for recovery of active materials and current collector materials of electrodes of a battery as claimed in claim 10, wherein sieve trays (212,214) are configured to convey said segregated cathode and anode electrodes in the respective solvent tanks (208,210) and the respective agitator tanks (216,218) for easy handling and removal of the current collector materials .

13. The system (200) for recovery of active materials and current collector materials of electrodes of a battery as claimed in claim 10, wherein drain outlets (224,226) of the respective agitator tanks (216,218) are configured for recovery of the settled active materials from the bottom of the respective agitator tanks (216,218).
14. The system (200) for recovery of active materials and current collector materials of electrodes of a battery as claimed in claim 10, wherein said pre-determined solvent used in the respective solvent tanks (208,210) comprises from at least one of acetic acid, acetone or ethyl formate.

15. The system (200) for recovery of active materials and current collector materials of electrodes of a battery as claimed in claim 10 and 14, wherein selection of said pre-determined solvent used in the respective solvent tanks (208,210) is based on Hansen Solubility Parameters and are non-toxic and can be available easily.

16. The system (200) for recovery of active materials and current collector materials of electrodes of a battery as claimed in claim 10, wherein said agitator tanks (216,218) comprises water for weakening the binder l used for binding the active materials on current collector material.
17. A method and system for recovery of active materials and current collector materials of electrodes of battery as claimed in claim 1 and 10 wherein said batteries are configured with recovery of all types of Li ion batteries like prismatic, pouch, cylindrical, etc.
18. A method and system for recovery of active materials and current collector materials of electrodes of battery as claimed in claim 1 to 10, wherein said batteries are configured to be fresh batteries or secondary usage batteries or tertiary usage batteries and so on.
, Description:FORM 2

THE PATENTS ACT, 1970
(39 of 1970)
&
THE PATENT RULES, 2003

COMPLETE SPECIFICATION
(See Section 10 and Rule 13)

Title of invention:
METHOD AND SYSTEM FOR RECOVERY OF ACTIVE MATERIALS AND CURRENT COLLECTOR MATERIALS OF LITHIUM ION BATTERY

Applicant:
Tata Motors Limited
A company Incorporated in India under the Companies Act, 1956
Having address:
Bombay House, 24 Homi Mody Street,
Hutatma Chowk, Mumbai 400001,
Maharashtra, India

The following specification describes the subject matter and the manner in which it is to be performed.
FIELD OF THE INVENTION
The present disclosure generally relates to a method for recycling a lithium-ion-batteries. More particularly, the present disclosure relates to a method for recovery of active materials and current collector materials s from the lithium-ion battery.
BACKGROUND OF THE INVENTION
In recent times, popularity of lithium-ion batteries has increased tremendously and finds several applications viz. batteries of laptops, mobile phones, tablets, power tools and electrical storage systems etc.

In addition to the above mentioned applications, the auto industry has large scale use of lithium-ion battery. The sale and use of electric vehicles (EVs) is bound to increase rapidly as many countries are promoting hybrid and EVs through legislation. As the popularity of electric vehicles starts to grow explosively, so does the pile of scrapped lithium-ion batteries viz. lithium-iron phosphate (LFP) battery, Lithium Cobalt Oxide battery ( LCO), Lithium Manganese Oxide ( LMO) and lithium nickel manganese cobalt (NMC) battery, that had once powered those cars, has increased. These popular power packs contain many materials including valuable metals. Hence, there is a necessity to recover, process and reuse these valuable materials. As per the rules and regulations of of battery waste management, the onus of recycling & disposal of scrapped batteries lies on original equipment manufacturer under extended manufacturer’s responsibility.

Conventionally, hydrometallurgy and pyrometallurgy are widely used recycling techniques for recovery of active materials from the scrapped lithium-ion batteries. Both the techniques require huge infrastructure and significant batch size. Further, active materials from the battery are processed and recovered in a single batch, where the single batch contains batteries of similar type i.e. either Lithium-iron phosphate battery (LFP) or lithium nickel manganese cobalt (NMC) or Lithium Cobalt Oxide battery (LCO) or Lithium Manganese Oxide ( LMO). Recyclers consider mixture of one type of battery with other type of battery as impurity and hence it becomes difficult to treat all types of batteries in a single batch under same recovery methods or processes. Hydrometallurgy includes large number of processes viz. battery discharging, shredding/crushing, magnetic separation, density separation and treatment with acid, alkali for recovery of active materials. This method uses shredding/crushing process, by which the collector material and active materials of electrodes are also shredded or crushed and e collector material and active material are recovered. . The recycling of batteries by using hydrometallurgy technique is popular for lithium batteries containing nickel and cobalt. Hydrometallurgy is profitable business for these batteries containing nickel and cobalt, as the recovered cobalt and nickel are having high economic value for its secondary use as compared to the operational cost of the recovery process.

Referring to Figure 1, a conventional method for recovery of active materials from lithium-ion battery using hydrometallurgy is disclosed. The hydrometallurgy method comprises the steps of discharging the battery. Further, the discharged battery is shredded/crushed to remove the plastic, followed by magnetic separation or any other equivalent technique to draw out the ferrous metals from non-ferrous materials. Furthermore, aluminum and copper are recovered using density separation or equivalent techniques followed by treatment of the remained powder fraction with various types of acids and alkalis to obtain and recover the active materials separately. However, hydrometallurgy is not preferred for recovery of materials from lithium-iron phosphate (LFP) battery, as the recovered materials in hydrometallurgy is lithium carbonate and iron-sulphate, which have low economic value in comparison with the operational cost of hydrometallurgy process. Further, there is no effective research/solution currently available to address recycling of the lithium-iron phosphate (LFP) battery in a simple and cost-effective manner with high rate of recovery and purity of active materials and current collector materials.

The present disclosure is directed to overcome one or more limitations stated above and any other limitations associated with the prior arts.

OBJECTS OF THE INVENTION
One object of the present disclosure is to recover various essential components and materials of the battery.
Another object of the present disclosure is to enhance recovery rate of active materials from the lithium-iron phosphate battery using a simple and cost-effective method.
Yet another object of the present disclosure is to use green and non-toxic solvents for weakening the binder adhesion of the active materials, current collector materials of the electrodes of the battery.
Another object of the present disclosure is to provide a method to enhance active material and current collector material separation efficiently.
Yet another object of the present disclosure is to recover active materials, current collector materials of the electrodes from the lithium-iron phosphate battery using minimum number of chemicals.
Yet, another object of the present disclosure is to recover active materials and current collector materials with higher purity.
Yet, another object of the present disclosure is to recover the electrodes and current collector materials in the original form for reuse in manufacturing of new batteries.

SUMMARY OF THE INVENTION
Before the present method and system for recovery of active materials, current collector materials of electrodes from a battery is described, it is to be understood that this application is not limited to a particular method and system for recovery of active materials, current collector materials of electrodes from a battery, as there may be multiple possible embodiments, which are not expressly illustrated in the present disclosures. It is also to be understood that the terminology used in the description is for the purpose of describing the particular implementations, versions, or embodiments only, and is not intended to limit the scope of the present application. This summary is provided to introduce aspects related to a method and system for recovery of active materials, current collector materials of electrodes from a battery. This summary is not intended to identify essential features of the claimed subject matter nor is it intended for use in determining or limiting the scope of the claimed subject matter.

In one embodiment, a method for recovery of active materials, current collector materials of electrodes from a battery is disclosed. The method comprises discharging, the battery in a discharging device. The next step of the method comprises conveying the discharged battery to a dismantling device for dismantling & separating the battery casing and electrodes of the battery. The further step of the method comprises conveying, the separated battery casing and electrodes of the battery, to a sorting device for segregating, the battery casing and electrodes of the battery. The next step of the method comprises segregating electrodes into cathode and anode and conveying segregated cathode and anode electrodes to respective solvent tanks for soaking, wherein the segregated electrodes are immersed in respective solvent tanks for a predefined time, for weakening the bond of the binder material used for binding the active materials to current collector materials of their respective electrodes. In the next step, the method comprises conveying, the soaked cathode and anode electrodes into their respective agitator tanks containing pre-determined solvent. Agitation further breaks the binding between the active materials and the current collector materials of their respective electrodes. In the next step, the method comprises removing, the separated active material and current collector materials from the respective agitator tanks. and after sieving, recovering the current collector material on the sieve and recovering active material from the bottom of the respective agitator tanks via a drain outlet mounted in the respective agitator tanks.

In another embodiment, a system for recovery of active materials, current collector materials of electrodes from a battery is disclosed. The system comprises a discharging device, configured to discharge the battery. Further, the system comprises a dismantling device, configured to receive the discharged battery conveyed from the discharging device for separating battery casing and electrodes of the battery. Furthermore, the system comprises a sorting device, configured to receive separated battery casing and electrodes of the battery conveyed from the dismantling device for segregating the battery casing and segregating electrodes into cathode and anode .. Moreover, the system comprises a plurality of solvent tanks, configured to receive the segregated cathode and anode electrodes in the respective solvent tanks, for weakening the bond of the binder material, which binds the active materials to current collector materials of e electrodes. Going further, the system comprises an agitator, configured to further e weaken the binder material in the pre-determined solvent, for separating the active materials and the current collector materials from their respective electrodes and a drain outlet, configured to recover the separated active materials from the bottom of the respective agitator tanks and recover and collection of current collector material from the sieve.

BRIEF DESCRIPTION OF DRAWINGS
The foregoing detailed description of embodiments is better understood when read in conjunction with the appended drawings. For the purpose of illustrating the present subject matter, an example of construction of the present subject matter is provided as figures; however, the present subject matter is not limited to the specific system for recovery of active materials from battery disclosed in the document and the figures.

The present subject matter is described in detail with reference to the accompanying figures. In the figures, the left-most digit(s) of a reference number identifies the figure in which the reference number first appears. The same numbers are used throughout the drawings to refer various features of the present subject matter.
FIG. 1 illustrates a conventional method for recovery of active materials from lithium-iron battery using hydrometallurgy (prior art).
FIG. 2 illustrates a schematic representation of method for recovery of active materials, current collector materials of electrodes of a battery, in accordance with one embodiment of the present disclosure.
FIG. 3 illustrates a schematic representation of construction of the lithium-iron phosphate (LFP) battery.

DETAILED DESCRIPTION
Some embodiments of this disclosure, illustrating all its features, will now be discussed in detail. The words "comprising," "having," "containing," and "including," and other forms thereof, are intended to be open ended in that an item or items following any one of these words is not meant to be an exhaustive listing of such item or items, or meant to be limited to only the listed item or items. It must also be noted that as used herein and in the appended claims, the singular forms "a," "an," and "the" include plural references unless the context clearly dictates otherwise. Although any method and system for recovery of active materials, current collector materials and the electrodes of battery and, similar or equivalent to those described herein may be used in the practice or testing of embodiments of the present disclosure, the exemplary, method and system for recovery of active materials, current collector materials and the electrodes of battery is now described.

Various modifications to the embodiment will be readily apparent to those skilled in the art and the generic principles herein may be applied to other embodiments. However, one of ordinary skill in the art will readily recognize that the present disclosure is not intended to be limited to the embodiments described but is to be accorded the widest scope consist in this regard, in a generic sense.

Figures 1-3 are now described using the reference numbers stated in the below table.
Reference Numeral Description
200 System for recovery of active materials, current collector materials of electrodes of a battery
202 Discharging device
204 Dismantling device
206 Sorting device
208 First solvent tank
210 Second solvent tank
212 First sieve tray
214 Second sieve tray
216 First agitator tank
218 Second agitator tank
220 Agitator of First agitator tank
222 Agitator of second agitator tank
224 Drain outlet of first agitator tank
226 Drain outlet of second agitator tank

Referring to Figure 2, a schematic representation of the method for recovery of active materials, current collector materials and the electrodes of a battery is disclosed.

Discharge of lithium-ion battery cells is vital for stabilization during lithium-ion battery disposal in order to prevent explosions, fires, and toxic gas emission. These are consequences of short-circuiting and penetrating high-energy lithium-ion battery devices, which can be hazardous to human health and the environment. Explosions, fires, and toxic gas emission may also damage disposal infrastructure, and damage lithium-ion battery materials and could reduce the material value due to lower efficiency for recycling and materials reclamation. A proven way to prevent the abovementioned disasters is to conduct electrochemical discharge as the initial step to stabilize the battery using brine solution. Thus, the battery is stabilized in a discharging device 202, wherein the discharging device 202 uses brine solution for stabilizing the battery to prevent explosion, fire and toxic gas emission. The battery is immersed in 5% NaCl solution for a period of 24 hours in order to discharge the battery to a lower voltage. Post completion of the battery discharge process, liquid is pumped for treatment and batteries are loaded on to a conveyor.

Once the battery is discharged using brine solution, it is dismantled in an dismantling device 204 to separate its casing and electrodes. Only the separated electrodes comprising both cathode and anode are then considered for further treatment.

Electrodes are subjected for sorting using sorting device 206, where cathode, anode and plastic separator are sorted. Plastic separator is removed & only anode & cathode are selected for further treatment.

The separated cathode of the battery received from the sorting device 206 is then conveyed to a first sieve tray 212, wherein the first sieve tray 212 is configured for mounting in a first solvent tank 208. The separated anode of the battery received from the sorting device 206, is conveyed to a second sieve tray 214, wherein the second sieve tray 214 is configured for mounting in a second solvent tank 210.

The first solvent tank 208 and the second solvent tank 210 comprises a pre-determined solvent which is crucial for weakening the bond which binds the active material to current collector material i.e. Lithium iron phosphate to aluminum foil of the cathode. Further, the pre-determined solvent is crucial for weakening the bond binding the active material to current collector material i.e. graphite to copper foil of the anode. The first sieve tray 212 comprising cathode is conveyed for mounting in a first solvent tank 208. The first solvent tank 208 comprises pre-determined solvent for weakening the bond of the binder material between the active material and current collector material of cathode. Further, the second sieve tray 214 comprising anode is conveyed for mounting in a second solvent tank 210. The second solvent tank 210 comprises pre-determined solvent for weakening the bond of the binder material between the active material and current collector material of anode. Both cathode and anode are soaked in the pre-determined solvents of the first solvent tank 208 and the second solvent tank 210 at room temperature for a predefined time i.e. 15 minutes.

However, merely soaking the cathode and the anode in pre-determined solvents does not result in complete separation of active materials from current collector materials of the respective electrodes. Thus, the cathode and anode are then subjected to further treatment for separation of the active materials from current collector materials.

After soaking, the soaked cathode along with the first sieve tray 212 is conveyed from the first solvent tank 208 to the first agitator tank 216. Further, the soaked anode along with the second sieve tray 212 is conveyed from the second solvent tank 210 to the second agitator tank 218. The first agitator tank 216 and the second agitator tank 218 are configured for mounting the first sieve tray 212 and the second sieve tray 214. Further, the first agitator tank 216 and the second agitator tank 218 are equipped with agitator’s (220, 222) respectively for stirring the electrodes in pre-determined solvent in order to weaken the binder material to separate the active materials from the current collector material of their respective electrodes.

Initially, the agitators (220, 222) mounted in the first agitator tank 216 and the second agitator tank 218 respectively are kept idle and not operated for a pre-defined time i.e. 15 minutes. After completion of the pre-defined idle period, the agitators (220, 222) are operated for a pre-defined time for recovery of the active materials from the current collector materials of cathode and the anode.

Due to agitation of the solvent in the first agitator tank 216, the binder material weakens the bond between active material and current collector material s in the solvent and the active materials are separated from the current collector material of cathode. Further, the current collector materials of cathode are trapped in the first sieve tray 212 mounted in the first agitator tank 216. Furthermore, the separated active materials are in powder or in flake form. The active materials then pass through the first sieve tray 212 thereby trapping the current collector materials of the cathode in the first sieve tray 212, wherein the separated active materials settle at the bottom of the first agitator tank 216. Similarly, due to agitation of the solvent in the second agitator tank 218, the binder material weakens the bond between active material and current collector material in the solvent and the active materials are separated the current collector material of the anode. Further, the current collector materials of anode are trapped in the second sieve tray 214 mounted in the second agitator tank 218. Furthermore, the separated active materials are in powder or in flake form. The active materials then passes through the second sieve tray 214 thereby trapping the current collector materials of the anode in the second sieve tray 214, wherein the separated active materials settles at the bottom of the second agitator tank 218.

The active material separated from the respective electrodes settles at bottom of the tank, while the current collector materials trapped in the respective sieve trays mounted in the respective agitator tanks.

The settled d active materials from cathode in powdered or flake form are recovered from a first drain outlet 224 of the first agitator tank 216. The settled active material from anode in powdered or flake form are recovered from the second drain outlet 226 of the second agitator tank 218. The first agitator tank 216 and the second agitator tank 218 comprise water as a solvent.

The current collector materials of cathode are trapped in the first sieve tray sieve 212, mounted in the first agitator tank 216, while the current collector materials of anode are trapped in the second sieve tray 214, mounted in the second agitator tank 218. Sieve trays 212 and 214 are removed from first agitator tank 216 and second agitator tank 218 for recovery of current collector materials.

Prior to treatment of the electrodes, suitable solvents for weakening the bond between the active materials and current collector materials of their respective electrodes, is determined using Hansen Solubility Parameters.

The method for determining suitable solvents for weakening the bond comprises identification of solvents which are common and easily available. In this case, 100 common solvents were identified. The identified common solvents are then classified into toxic and non-toxic solvents. In order to ensure safe and environmentally friendly recovery of the active materials of the battery, only the non-toxic solvents are considered. Based on the classification of the solvents, only 17 solvents from the initial list of 100 common solvents qualify as non-toxic solvents.

According to Hansen concept, for dissolution of a polymer in a solvent, individual forces of attraction (dD, dP and dH) of both the polymer and solvent should be similar. To find out whether a polymer dissolves in a solvent, the relative distance between these parameters are found out as (Ra). This distance is divided by the radius of interaction of the polymer to get RED value. (The solid polymer has a spherical region around it and solvents whose Hansen solubility parameters lie inside this region is said to dissolve the polymer}

Materials, generally have two types of forces of attraction i.e. inter-molecular force of attraction and intra-molecular forces of attraction. Inter-molecular attraction forces are those forces, which are present between different molecules of the same material whereas intramolecular attraction forces are those forces which are present inside a molecule due to different atoms.

Dispersion energy parameter (dD) and hydrogen bonding energy (dH) are inter-molecular forces of attraction whereas polar bonding energy (dP) is intra-molecular force of attraction. Every material has both intra and inter molecular forces of attraction. The dispersion energy parameter (dD) can be defined as the energy due to dispersion forces between molecules. Further, polar bonding energy (dP) can be defined as the energy due to dipolar intramolecular force. Furthermore, hydrogen bonding energy (dH) can be defined as the energy due to hydrogen bonds between molecules.

Relative energy difference (RED) = Ra / Ro, where Ra is the relative distance between respective Hansen solubility parameters and Ro is interaction radius of the polymer.

Further, Relative Energy Difference (RED) was calculated using Hansen Solubility Parameters for the previously shortlisted 17 non-toxic solvents & Polyvinylidene fluoride (PVDF) as a binder used to bind active material to current collector materials of both anode and cathode electrodes. using e using dD (dispersion energy parameter), dP (polar bonding energy ), dH ( hydrogen bonding energy) values from the literature. The relation between RED, dD, dP and dH is shown in the below formula.
Ra= v(4(dDPVDF-dDsolvent)² + (dPPVDF-dPsolvent)² +(dHPVDF-dHsolvent)²)

RED was computed as follows:

RED = Ra/Ro Ro for PVDF=9.6 {from literature}

For acetic acid as a solvent,

Ra=v(4*?(17-14.5)?^2+?(12.1-8)?^2 ?+(10.2-13.5)?^2 ) =7.259

RED= Ra/Ro =7.2594/9.6 =0.7561

The Relative Energy Difference (RED) was calculated for the 17 non-toxic solvents using the above formula. The RED calculations have been carried out considering PVDF (Polyvinylidene Fluoride) as a binder material used to bind active material to current collector materials of both anode and cathode electrodes of the battery.

RED values for shortlisted solvents with respect to PVDF using Hansen’s solubility parameter are shown in the table 1.

Table 1
Based on the RED calculations as seen in table 1, only 11 non-toxic solvents out of the 17 non-toxic solvents were found to have RED below or around 1.

The solvents having RED (Relative Energy Difference) less than or around 1 as seen in table 1, were selected as a solvent to conduct further experiments for separating active materials from current collector materials of cathode which Aluminum foil

Cathode was immersed in the 11 non-toxic solvents having RED 1 or less than 1 for a predetermined duration at room temperature. Further, the cathode immersed in the solvents was taken out and agitated in water for a predetermined duration.
Cathode Separation efficiency was calculated using the following formula.
(CSE)= (Initial mass of cathode-Final mass of cathode without coating)/Initial mass of cathode

The calculations for cathode separation efficiency are shown in the table 2 for the 11 non-toxic solvents.

Table 2
Further, solvents showing cathode coating separation efficiency more than 80% from the table 2 were selected to conduct experiment on anode. As evident from table 2, the solvents suitable for weakening the binder adhesion between active material from current collector material of cathode are acetic acid or acetone or ethyl formate at room temperature for a predetermined time followed by agitation in water for a predetermined time to remove the active materials.
.
Further, anode is soaked in acetic acid or acetone or ethyl formate solvents at room temperature for a predetermined time followed by agitation in water for a predetermined time to remove the active materials.

In one embodiment, a method for recovery of active materials and current collector materials of d electrodes of a battery is disclosed. The method comprises the steps of discharging, the battery in a discharging device (202) followed by conveying, the discharged battery to a dismantling device (204). for separating the battery casing and electrodes of the battery and conveying, the separated battery casing and electrodes of the battery, to a sorting device (206). Furthermore, the method comprises segregating, the battery casing and electrodes of the battery into cathode and anode, in a sorting device (206) and conveying, the segregated cathode and anode electrodes to sieve trays 212 and 214, which are mounted in solvent tanks (208,210) respectively for soaking, the segregated electrodes in respective solvent tanks (208,210) for a predefined time, for weakening the bond between the active material from current collector material of their respective electrodes;. Moreover, the method comprises conveying, the soaked electrodes into their respective agitator tanks (216,218) followed by agitating, the respective agitator tanks (216,218) for weakening the bond between active material and current collector material, in the pre-determined solvent for separating the active material from the current collector material of their respective electrodes. Separated active materials and current collector materials are then recovered from the agitator tanks (216,218). The last step of the method comprises removal of sieve trays 212 and 214 from first agitator tank 216 and second agitator tank 218 respectively for recovery of the current collector material and active materials , settled at the bottom of the agitator tanks (216,218) is collected via drain outlets (224,226) of the respective agitator tanks (216,218).

The method for recovery of active materials and current collector materials of electrodes of a battery uses brine solution for discharging the battery in order to prevent explosion, fire and toxic gas emission during recovery of active materials from the electrodes of the battery. Further, the segregated electrodes after sorting are conveyed in sieve trays (212,214) for mounting in the respective solvent tanks (208,210). Furthermore, sieve trays (212,214) having soaked electrodes are conveyed and mounted to the respective agitator tanks (216,218). Moreover, separated active materials and current collector materials are recovered after agitation of electrodes in sieve trays (212,214), which are mounted in the respective agitator tanks (216,218).

The method for recovery of active materials and current collector materials of electrodes of a battery comprising weakening the binder material used to bind active material to current collector material of electrode, in the solvent depends upon the RED values of the solvent with respect to the binder. Further, the pre-determined solvent used in the respective solvent tanks (208,210) comprises at least one of acetic acid, acetone or ethyl formate. The separated current collector materials trapped in sieves 212 and 214 mounted on the respective agitator tanks (216,218) are recovered as an intact unit for secondary use. While active materials settled at bottom of the respective agitator tanks (216,218), are recovered through drain outlets 224 and 226 respectively.

In another embodiment, a system (200) for recovery of active materials and current collector materials of electrodes of a battery is disclosed. The system (200) comprises a discharging device (202), configured to discharge the battery Further, the system comprises a dismantling device (204), configured to receive the discharged battery conveyed from the discharging device (202), for separating battery casing and electrodes of the battery. Furthermore, the system (200) comprises a sorting device (206), configured to receive separated battery casing and electrodes of the battery conveyed from the dismantling device (204), for segregating the battery casing and electrodes into cathode and anode of the battery. Moreover, the system (200) comprises a plurality of solvent tanks (208,210), configured to receive the segregated electrodes in sieve trays (212, 214) mounted in the respective solvent tanks (208,210), for weakening the bond of the binder material between the active material and current collector material of their respective electrodes and transferring sieve trays (212, 214) to an agitator tanks (216, 218) having agitators (220,222), configured to weaken binder material which is binding active material on current collector materials , in the pre-determined solvent, for separating the active materials from the current collector materials of their respective electrodes. Further, the system (200) comprises a drain outlet (224,226), configured to recover the settled active materials at the bottom of the respective agitator tanks (216,218) and current collector material is trapped in sieve (212, 214).

The system (200) for recovery of active materials and current collector materials of their electrodes of a battery comprising discharging device (200) is configured to stabilize the battery for preventing explosion, fire and toxic gas emission during recovery of active materials from the current collector material of electrodes of the battery. The system (200) further comprises conveying the separated battery casing and electrodes of the battery to said sorting device (206). Furthermore, the system comprises sieve trays (212,214) to receive the segregated cathode and anode electrodes of the battery from the sorting device (206), for conveying said segregated cathode and anode electrodes to respective solvent tanks (208,210). The system (200) comprising said solvent tanks (208,210) and said agitator tanks (216,218) are configured for mounting said sieve trays (212,214).

Furthermore, said drain outlets (224,226) of the agitator tanks (216,218) are configured to filter the solvent of the agitator tank (216,218) for recovery of the separated active materials settled at the bottom of the agitator tank (216,218) in powdered or flake form Moreover, said pre-determined solvent used in the respective solvent tanks (208,210) comprises at least one of acetic acid, acetone or ethyl formate.

In one embodiment, a binder material for binding, the active material to the aluminium foil which is current collector of the cathode or the copper foil , which is current collector of the anode can be Polyvinylidene fluoride (PVDF), Styrene Butadiene Rubber (SBR), Carboxymethyl Cellulose (CMC), Polyacrylonitrile (PAN) etc.

Referring to Figure 3, construction of a lithium-iron phosphate (LFP) battery is disclosed. The LFP battery comprises cathodes and anodes alternately stacked and electrically isolated by the plastic separator. The active material i.e. lithium-iron phosphate of the cathode is adhered to aluminium foil which is current collector material, by binder (polyvinylidene fluoride (PVDF)), making it difficult to separate the active material from the current collector. Further, the active material i.e. graphite of the anode is adhered to copper foil which is current collector, by binder (polyvinylidene fluoride (PVDF)) making it difficult to separate the active material from the current collector.

A method and system for recovery of active materials and current collector materials of their electrodes disclosed is for of all types of Li ion batteries like prismatic, pouch, cylindrical, etc.

The system and method disclosed can be used for recovery of active materials from the cathode and the anode of a lithium-ion battery and also recovery of current collector materials of cathode and anode of lithium ion battery.

Exemplary embodiments discussed above may provide certain advantages. Though not required to practice aspects of the disclosure, these advantages may include the following:

Some embodiments of the present subject matter disclose a method and system for recovery of active materials from current collector material of electrodes of lithium-iron phosphate battery.

Some embodiments of the present subject matter disclose a method that enhances recovery rate of active materials from current collector material of electrodes of the lithium-iron phosphate battery using a simple and cost-effective method.

Some embodiments of the present subject matter provides a method that enhances separation efficiency of active materials from current collector materials.

Some embodiments of the present disclosure enable recovery of active materials and current collector materials of electrodes of the lithium-iron phosphate battery using minimum number of chemicals and with high degree of purity.

Although implementations for recovery of active materials from current collector materials of electrodes of lithium-iron phosphate battery have been described in language specific to structural features and/or system, it is to be understood that the appended claims are not necessarily limited to the specific features or described. Rather, the specific features are disclosed as examples of implementations.