Method for recycling phosphate batteries

Abstract

The present invention relates to a novel recycling route for batteries used in the sector of electro-electronic equipment and in the automotive sector. This invention focuses on batteries of the prismatic, cylindrical and pouch types, containing lithium iron phosphate, LFP (LiFePO4), as the active material. The method comprises the following steps: discharging the batteries, dismantling and separating battery components, grinding battery cells, precipitating fluorine and lithium, leaching with acid, separating the iron with precipitation and an ion exchange resin, precipitating aluminium, and precipitating the remaining lithium. The present invention includes an acid leaching step without the use of an oxidising agent, which can reach values close to 99% efficiency for Li and Fe, and mechanical processing without any heat treatment to concentrate the metals of interest from the battery cathodes.

Description

“PHOSPHATE BATTERY RECYCLING PROCESS” TECHNICAL FIELD OF THE INVENTION

[0001] This invention relates to the process of recycling lithium iron phosphate Li-ion batteries, LFP (LiFePO4), from the electronics and automotive sector using mechanical processing and hydrometallurgical route for pouch, cylindrical and prismatic type batteries. BACKGROUND OF THE INVENTION

[0002] Li-ion batteries are the leading technology for use in electronic devices and electric vehicles. Due to the shift toward a society with lower greenhouse gas emissions, the consumption of these batteries for electric vehicles could increase in capacity up to tenfold by 2030. Global consumption of Li-ion batteries is estimated to reach US$221 billion from 2015 to 2024.

[0003] Lithium is considered a critical and strategic element in the world's major economies. Demand for lithium will grow to the point where current production from mining will no longer be sufficient to meet market demand, especially for Li-ion batteries. Therefore, the search for other sources of lithium is crucial, with recycling playing an important role in promoting the circular economy. Another important aspect of Li-ion batteries as a secondary source of lithium is the higher concentration of this element in batteries than in primary sources, such as spodumene and lepidolite.

[0004] Improper disposal of batteries after their useful life can cause serious negative impacts on the environment and society, including soil and water contamination and, consequently, human health. Therefore, proper disposal of these batteries is essential to prevent pollution.

[0005] . The main difference between Li-ion batteries is the models, which can be pouch, cylindrical or prismatic, and the type of active material applied, which can be type LCO (LÍC0O2), NCA (LÍNÍC0AIO2), NMC (LiNixMriyCozC, where x+y+z = 1) or LFP (LiFePCU).

[0006] . Batteries with LFP (LiFePCU - lithium iron phosphate) active material have advantages over other Li-ion batteries for use in large-scale electric vehicles or energy storage facilities due to their low cost, non-toxicity, high capacity, thermal stability and good charge-discharge cycle performance.

[0007] Despite the importance of LFP batteries, little or nothing is done regarding their recycling. There are two traditional routes for recycling Li-ion batteries: pyrometallurgical and hydrometallurgical. Pyrometallurgical processes involve high-temperature steps and must be combined with the hydrometallurgical route to separate the metals and obtain high-purity products, i.e., with contents above 95%. Another drawback of the pyrometallurgical process is that lithium is not recovered, being lost in the slag generated in the high-temperature steps. Nevertheless, current processes have low lithium recovery yields.

[0008] Existing hydrometallurgical processes for LFP batteries utilize heat pretreatment, leaching (acid or alkaline), and separation and purification steps to obtain the product. Among these steps, leaching is crucial to the process, as it is at this stage that the elements present in the active material are extracted and then passed into the aqueous phase. Therefore, separation and purification steps are necessary to obtain high-purity products. This route has the advantage of lower energy consumption and lower greenhouse gas emissions.

[0009] Li-ion battery recycling processes typically focus on other types of batteries, such as LCO, NCA, and NMC. However, as demonstrated in the applications of LFP batteries, the large vehicle market will be dominated by these batteries, which will be discarded at the end of their useful life. As a way to avoid social and environmental impacts, recycling LFP batteries will be of great importance in promoting the circular economy, reinserting critical metals such as lithium back into the market.

[0010] . Document US10919775 refers to the production of lithium carbonate from the recycling of LFP batteries. In the process, the discarded battery is ground, and the aluminum foil is separated from the active material (cathode). After an acid leaching step (using mineral acids) of the active material with the addition of an oxidizing agent, the iron is not leached, resulting in only a lithium solution.

[0011] . Document CN1051 19024A reports a pretreatment step prior to an LFP cathode leaching step. After this pretreatment step, the solid material reacts with an acidic solution to leach the lithium, which then proceeds to the precipitation step.

[0012] , Document CN106848473B describes calcination (heat treatment) steps as a pretreatment for LFP batteries to remove aluminum, and the material containing lithium and iron undergoes grinding steps in a ball mill. The resulting material is leached in an acidic medium with the addition of an oxidizing agent.

[0013] However, the recycling process for LFP Li-ion batteries has particularities compared to other lithium batteries, such as the processing of aluminum present in the electron collector composition. Furthermore, the most selective leaching steps for lithium still contain some of the leached iron. Therefore, separation and purification steps are necessary to remove the aluminum and iron before obtaining lithium as a product.

[0014] , Therefore, there is a gap in the development of a recycling process focused on LFP Li-ion batteries applicable to different types of batteries, such as pouch, cylindrical and prismatic batteries, with less environmental impact, lower cost and technically viable. OBJECTIVES OF THE INVENTION

[0015] . In this sense, the present invention has an objective of providing a process for recycling LFP (LiFePO4) batteries of the pouch, cylindrical and prismatic types from the electronics and automotive markets, the latter being the main object of this invention.

[0016] . This invention also aims to provide physical processing of LFP batteries without any type of heat treatment and without an oxidizing agent in the leaching stage.

[0017] , Additionally, this invention aims to provide physical processing of LFP type batteries and, in chemical processing, to separate iron and aluminum before obtaining lithium as a product. SUMMARY OF THE INVENTION

[0018] . Features and advantages of the invention will be set forth, in part, in the following description, or may be obvious from the description, or may be learned through practice of the invention.

[0019] . In a first embodiment, the lithium iron phosphate battery recycling process of the present invention has the following steps: discharging the batteries to be recycled; disassembling and separating the battery components, in which the separation is made into groups: electronic parts and protective structure, and battery cells; grinding the battery cells, in which the grinding is carried out in coolant fluid; separating, from the ground material from the grinding stage, plastic parts of the battery cells, in which the graphite and active material follow in the process; precipitate fluorine from the solution from the separation step with the addition of Ca(OH)2 or CaCh, in which the precipitated fluorine is removed from the solution through a filtration step; precipitate lithium from the solution from the fluorine precipitation step with the addition of NaaPC or Na2CO3, in which the precipitated lithium is removed from the solution through filtration; leach the solution from the lithium precipitation step with acid; filter the leached solution to separate the leaching liquor and solid material; separate the filtered solid material containing the external structure of aluminum, aluminum foils, copper and graphite; separate iron from the leached solution from the filtration step with the addition of NaOH or Na2CÜ3; remove remaining iron after the iron separation step, in which the remaining iron is removed using ion exchange resins; precipitate aluminum from the solution from the remaining iron removal step with the addition of NaOH or Na2CÜ3;precipitate the remaining lithium, after the precipitation of aluminum, by crystallization or addition of at least one of sodium phosphate, sodium carbonate and calcium hydroxide.;

[0020] In an alternative embodiment, the lithium iron phosphate battery recycling process of the present invention may include an additional step of separating aluminum by electrodialysis. This alternative embodiment of the invention has the following features: a step of separating aluminum from the solution by electrodialysis with a cationic and anionic membrane after the step of removing the remaining iron, in which the electrodialysis is performed at an electric current range of 200 mA to 400 mA and a reaction time of up to 30 hours, and in which the concentrated aluminum solution proceeds to the aluminum precipitation stage.

[0021] , It is possible to resynthesize the cathode of recycled lithium iron phosphate batteries using the present invention. For this resynthesis, the iron phosphate obtained by the process disclosed herein is added to a lithium solution, with the pH adjusted to 5.0, and the addition of ascorbic acid at a concentration of up to 0.05 mol / L. The Li:Fe:PCU ratio in the solution is adjusted with the addition of LiOH, Fe(OH)2, or LiPC. The solution is then transferred to a pressure reactor, where the mixture is stirred and heated to a temperature of approximately 200°C for a reaction period of up to 6.0 hours. After this reaction, the final solution is filtered, and the LiFePC cathode is obtained.

[0022] , The present invention is aimed at recycling processes focused on LFP type Li-ion batteries applicable to different types of batteries, such as pouch, cylindrical and prismatic batteries, with less environmental impact, lower cost and technically viable. BRIEF DESCRIPTION OF THE FIGURES

[0023] . A complete and feasible description of the present invention, which includes the best mode thereof, directed to a person of ordinary skill in the art, is presented in the descriptive report, which makes reference to the attached figures, in which: Figure 1 illustrates a flowchart of a first embodiment of the battery recycling process of the present invention; and Figure 2 illustrates a flowchart of a second embodiment of the battery recycling process of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0024] , Reference will now be made in detail to the embodiments of the invention, one or more examples of which are illustrated in the drawings. Each The example is provided by way of explanation of the invention, without limitation thereof. Indeed, it will be apparent to those skilled in the art that various modifications and variations may be made to the present invention without departing from the scope or spirit of the invention. For example, the functions illustrated or described as part of some embodiments may be used with another embodiment to produce yet a further embodiment. Accordingly, the present invention should encompass such modifications and variations as they are presented within the scope of the appended claims and their equivalents.

[0025] . In general, as can be seen in Figure 1, the LFP battery recycling process of the present invention, preferably prismatic, cylindrical and pouch type batteries, has mechanical processing of the batteries (without any heat treatment to concentrate the metals of interest in the battery cathodes) with steps of: discharging the batteries 101 to be recycled; disassembling and separating the components of the battery 102, in which the separation is made into groups: electronic parts and protective structure, and battery cells; grinding the battery cells 103, in which the grinding is carried out in coolant fluid (wet grinding, which avoids the risk of explosions, unlike existing processes), preferably water; separating 104, from the ground material from the grinding step 103, plastic parts of the battery cells, in which the plastic parts are washed and sieved 1 15, and the graphite and active material continue in the process.After mechanical processing of the batteries, there is a step to precipitate fluorine 105 from the solution coming from separation step 104 with addition of Ca(OH)2 or CaCh, in which the precipitated fluorine is removed from the solution through a filtration step 1 16, with a filter having pores of 0.1 to 4 pm, then there is a step to precipitate lithium 106 from the solution coming from fluorine precipitation step 105 with addition of NaaPC or Na2CO3, in which the precipitated lithium is removed from the solution through filtration 1 17, with a filter having pores of 0.1 to 4 pm. Then, the. hydrometallurgical processing of the present invention, with a step for leaching with acid 107 the solution from the lithium precipitation step 106; followed by a step for filtering the leached solution 108 to separate the leaching liquor and solid material, with a filter having pores of 0.1 to 4 pm.After leaching 107, there is a step to separate the filtered solid material 109 that contains aluminum outer structure, aluminum foils, copper and graphite; a step to separate iron 110 from the leached solution coming from filtration step 108 with addition of NaOH or Na2CÜ3; a step to remove remaining iron 111 after iron separation step 110, in which the remaining iron is removed using ion exchange resins; a step to precipitate aluminum 112A from the solution coming from remaining iron removal step 111 with addition of NaOH or Na2CÜ3; and a step to precipitate remaining lithium 113 from the solution coming after aluminum 112A precipitation by crystallization or addition of at least one of sodium phosphate, sodium carbonate and calcium hydroxide.

[0026] The first step of the process is to discharge the batteries 101 to be recycled. Discharging is preferably done in two resistance discharge stages to eliminate remaining electricity or recover electrical energy. For example, the discharge stage 101 can be performed with Ni-Cr and metallic Cu resistors connecting the battery terminals in series or parallel for 12 to 24 hours. Next, the battery components 102 are disassembled and separated into two groups: electronic parts and protective structure, including plastic, aluminum, or steel; and battery cells.The grinding of LFP 103 battery cells, preferably LFP cylindrical batteries, can be done in a shredder or knife mill with the constant addition of coolant, preferably water (wet grinding, which avoids the risk of explosions, unlike existing processes), the battery cells are inserted into the mill at intervals of 1 to 20 seconds between each part and the material. The ground material has a particle size of less than 50 mm. After grinding (103), the plastic material from the batteries (104) is separated, which can be done by washing with water and by decantation, centrifugation, or vibrating table. Separation can be done by sieving; the plastic parts of the battery cells (polypropylene and high- and low-density polyethylene) are washed and sieved (15). They can be removed through a sieve with a mesh opening size of 0.1 to 4 mm. The graphite and active material proceed to the next stages of the process. The removed plastic parts are washed to remove any graphite (anode) remaining in the plastic, and this wash water is reincorporated into the flow that continues for fluoride precipitation (105).

[0027] , The solution without the plastic material then proceeds to the fluoride precipitation step 105 with calcium hydroxide (Ca(OH)2) or calcium chloride (CaCh). The addition of Ca(OH)2 or CaCh is in an amount between stoichiometric and 20% excess, with a reaction time of up to 2.0 hours, and in a temperature range of 25°C to 90°C. The precipitated fluoride is removed from the solution through a filtration step 116, with a filter having pores of 0.1 to 4 pm.

[0028] . Next comes the lithium precipitation step 106, in which lithium is precipitated with the addition of NaaPC or Na2CO3. Lithium precipitation is performed by adding an amount of Na2CÜ3 that is between stoichiometric and 20% excess, with a reaction time of up to 2.0 hours, in a temperature range of 20°C to 80°C, and with a yield of at least 10% lithium precipitation.

[0029] . After the lithium precipitation step 106, the precipitated lithium passes through a filtration step 117 and the water used for filtration can then be recirculated in the process, and can return and feed the grinding step 103.

[0030] . The external structure of the battery cells (without plastic parts), graphite, active material, the aluminum and copper foils that are present in the solution from the grinding step 103, go to the leaching step 107. In this step, the acids Sulfuric and citric acids can be used, preferably sulfuric acid. Acid concentrations range from 0.2 mol / L to 4.0 mol / L over a temperature range of 25°C to 90°C. The reaction time can range from 0.5 to 5.0 hours. No oxidizing agent is used in the leaching step. The efficiency of the leaching process of the present invention can reach 99% of the metals present in the active material, even without the presence of an oxidizing agent, due to the presence of the metallic aluminum foil of the battery cells. The efficiency of the leaching step 107 of the present invention can be seen in Table 1, which shows a comparison between the results obtained with the process claimed herein and prior art processes that use an oxidizing agent or another type of acid different from those employed in the present process. Table 1

[0031] . References from Table 1: (a): 99% aluminum leaching from the active material, and 70% aluminum leaching considering the active material + electron collecting foil; *not informed.

[0032] , After the leaching step 107 there is a filtration step 108 to remove solid material from the solution (external structure of the battery cells, aluminum, copper and graphite sheets). The obtained liquor (aqueous phase) goes to the separation (purification) step of the metals present, and the solid material (leaching residue) goes to the sieving and elutriation step 109 (physical separation). In the screening and elutriation step 109, a screening step is performed to recover the graphite, while the outer structure of the battery cells, the aluminum foils, and the copper foils are recovered through an elutriation step. In elutriation, performed in a conventional elutriator, water is fed from below the tank (or column), and the aluminum foils exit at the top (overflow), while the copper and the outer structure of the battery cells exit at the bottom of the tank (underflow).

[0033] The liquor obtained in the leaching step contains the metals lithium, iron, and aluminum. The first separation step for these metals is the iron-110 separation step using Na2Cu3 or NaOH as a precipitating agent in batch reactors. It is important to note that an oxidizing agent, H2O2, air, or O2, can be added to increase the redox potential (oxidation potential) of the solution from 0.3V to 0.7V, to oxidize the iron ions and aid in precipitation. However, such an oxidizing agent is not used in the leaching step, as is typically used in the prior art. The precipitating agent, preferably Na2CO3, can be added in solid form or in solution to reach a concentration of up to 1.0mol / L of precipitating agent in the solution, until a pH for FePCU precipitation is reached in the range of 1.5 to 3.5.The reaction occurs in a period of 0.25 to 4.0 hours and a temperature range of 25°C to 80°C, in which the obtained product FePCU is separated through filtration, with a filter having pores of 0.1 to 4 pm.

[0034] , It is noteworthy that the presence of iron in aluminum hydroxide precipitates (AI(OH)3) impairs the final use of the product, therefore, all possible iron must be removed to increase the purity of the products obtained later. Therefore, after the iron separation step 110, a remaining iron removal step 11 1 is performed using an ion exchange resin with a functional group among aminophosphonate, iminodiacetate, aminophosphonic or bis-picolylamine, preferably aminophosphonic. The remaining iron removal step 1 1 1 can be performed in a batch process or, preferably, in a continuous system, for example, ion exchange columns. In the batch process removal, 0.2 to 2.0 kg of resin are used to treat approximately 10 L of solution, at a pH of 2.0 to 3.0, and a temperature range of 25 S C to 60 s C, in a reaction period of 0.5 to 6.0 hours. In a continuous system with resin-filled ion exchange columns connected in series with ascending or descending flow at a flow rate of 0.5 to 5 bed volumes / hour and a temperature of 25°C to 60°C. Preferably, a flow rate of 2VL / h to 4VL / h and a pH of 2.0 to 3.0 is used. For a continuous system, the removal of remaining iron can also be carried out in stirred reactors for 0.5 to 2.0 hours. Using the remaining iron removal step 111, all the iron present in the solution is removed as iron phosphate (FePO4) through filtration, with a filter having pores of 0.1 to 4 µm.

[0035] . The filtrate (solution) then proceeds to the aluminum 1 12A precipitation step using Na2CÜ3 or NaOH, preferably Na2CO3, in an amount between stoichiometric and 40% excess, in a temperature range of 25°C to 80°C, in a pH range of 3.0 to 7.0 and for a reaction time of 0.5 to 3.0 hours. In this case, aluminum hydroxide and aluminum carbonate can be obtained. It is possible to obtain aluminum oxide after heat treatment with a temperature range of 200°C to 800°C for a reaction time of 1.0 to 5.0 hours.

[0036] Another viable separation technique for aluminum is electrodialysis. Electrodialysis separation 112B, used to separate aluminum from the solution prior to the aluminum precipitation step 112A, shown in the embodiment illustrated in Figure 2, is performed with cationic and anionic membranes, using an electric current range of 200 mA to 400 mA for a reaction time of up to 30 hours. The concentrated aluminum solution then proceeds to the aluminum precipitation step 112A to obtain aluminum hydroxide, aluminum carbonate, or aluminum oxide, as explained above.

[0037] , Different types of lithium product can be obtained from the solution after precipitation of iron and aluminum.The remaining lithium precipitation step 113 can obtain, for example, i) lithium sulfate, from the crystallization of the solution in a temperature range of 80°C to 110°C, for a reaction period of 1.0 to 5.0 hours; ii) lithium phosphate, from the addition of sodium phosphate, in an amount between the stoichiometric and 40% excess, in the solution under stirring in a temperature range of 25 to 90°C for a reaction period of 1.0 to 5.0 hours; iii) lithium carbonate, with the addition of solid sodium carbonate or in solution in a concentration of 50 to 200 g / L, under stirring, in a temperature range of 25°C to 90°C for a reaction period of 1.0 to 5.0 hours; iv) lithium hydroxide, from lithium carbonate previously obtained with the addition of calcium hydroxide at a concentration of 0.2g / L to 1.0g / L, in a temperature range of 25°C to 90°C, for a reaction period of 1.0 to 5.0 hours.Lithium products are removed from the solution by filtration, with a filter having pore sizes of 0.1 to 4 pm.

[0038] . After the remaining lithium precipitation step 113, it is still possible to obtain sodium sulfate crystals as a byproduct through a crystallization process, in which the solution is evaporated at a temperature of 90°C to 110°C and a reaction time of 1.0 to 5.0 hours, since the filtrate (solution) contains sodium sulfate. The acids used in leaching and that remained in the solution until the precipitated lithium was removed can be returned to leaching step 107. This has the advantage of avoiding waste and disposal of the acid used during leaching.

[0039] . In the lithium iron phosphate battery recycling process 100 of the present invention, in the steps of fluorine precipitation 105, lithium precipitation 106, iron separation 110, removal of remaining iron 111, leaching 107, filtration of the leached solution 108, aluminum precipitation 112A, and precipitation of remaining lithium 113, the filters used have pores of 0.1 to 4 pm and are preferably of the paper or membrane types.

[0040] The new battery recycling process 100 of the present invention has a combination of process advantages, among which the following stand out: discharging the batteries without loss of materials; no heat treatment steps in the mechanical and chemical processing of the batteries to be recycled; grinding the batteries in water; no consumption of oxidizing agent in the leaching step; obtaining high-purity products from the active material of the battery cathode; the possibility of resynthesizing the cathodes from the leaching solution or from the products obtained in the recycling process; obtaining plastic, metallic copper, metallic aluminum and the external structure of the battery in the recycling of batteries by physical separation; an alternative for separating aluminum after leaching by means of electrodialysis; avoiding waste and disposal of acid used during leaching.

[0041] , Through the LFP lithium battery recycling process of the present invention, it is possible to resynthesize the LFP battery cathode. For resynthesis of the LFP battery cathode, the iron phosphate obtained after iron separation (1 10) and removal of the remaining iron (11 1) is added to a lithium solution, with the pH adjusted to 5.0, and the addition of ascorbic acid at a concentration of up to 0.05 mol / L. The Li:Fe:PCU ratio in the solution is adjusted with the addition of LiOH, Fe(OH)2, or LiPC. The solution is then transferred to a pressure reactor, where the mixture is stirred and heated to a temperature of approximately 200°C for a reaction period of up to 6 hours. After this reaction, the final solution is filtered, and the LiFePCU cathode is obtained. This specification uses examples to describe the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including producing and using any devices or systems and performing any methods incorporated therein. The patentable scope of the invention is defined by the claims and may include other examples that occur to those skilled in the art. Such other examples are intended to fall within the scope of the claims if they include structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal language of the claims.

Claims

CLAIMS 1. Process for recycling phosphate, lithium and iron batteries (100), CHARACTERIZED by the fact that it comprises the steps: discharging the batteries (101) to be recycled; disassembling and separating the battery components (102), in which the separation is made into groups: electronic parts and protective structure, and battery cells; grinding the battery cells (103), in which the grinding is carried out in coolant fluid; separating (104), from the ground material coming from the grinding step (103), plastic parts of the battery cells, in which the graphite and active material follow the process; precipitate fluorine (105) from the solution coming from the separation stage (104) with addition of Ca(OH)2 or CaCh, in which the precipitated fluorine is removed from the solution through a filtration step (1 16); precipitating lithium (106) from the solution coming from the fluorine precipitation step (105) with addition of NaaPC or Na2CO3, in which the precipitated lithium is removed from the solution through filtration (1 17); leaching with acid (107) the solution coming from the lithium precipitation step (106); filtering the leached solution (108) to separate leaching liquor and solid material; separating the filtered solid material (109) which contains external aluminum structure, aluminum foils, copper and graphite; separating iron (1 10) from the leached solution coming from the filtration step (108) with addition of NaOH or Na2COa; remove remaining iron (11 1 ) after the iron separation step (1 10), in which the remaining iron is removed using ion exchange resins; precipitate aluminum (112A) from the solution coming from the remaining iron removal step (1 1 1 ) with the addition of NaOH or Na2CÜ3; precipitate remaining lithium (1 13), after the precipitation of aluminum, by crystallization or addition of at least one of sodium phosphate, sodium carbonate, calcium hydroxide.

2. Process for recycling phosphate, lithium and iron batteries (100), according to claim 1, CHARACTERIZED by the fact that the recycled batteries are of the prismatic, cylindrical and pouch types.

3. Process for recycling phosphate, lithium and iron batteries (100), according to claim 1 or 2, CHARACTERIZED by the fact that the discharging step (101) is carried out in two resistance discharging steps to recover the electrical energy discharged from the batteries.

4. Process for recycling phosphate, lithium and iron batteries (100), according to any one of the preceding claims, CHARACTERIZED by the fact that the grinding step (103) is carried out in a shredder or knife type mill.

5. Process for recycling phosphate, lithium and iron batteries (100), according to any one of the previous claims, CHARACTERIZED by the fact that the grinding step (103) has a constant addition of cooling fluid, preferably water, in which the battery cells are inserted into the mill at intervals of 1 to 20 seconds between each part and the ground material has a particle size of less than 50 mm.

6. Process for recycling phosphate, lithium and iron (100) batteries (100), according to any one of the preceding claims, CHARACTERIZED in that the separation step (104) is carried out by at least one of decantation, centrifugation, and vibrating table.

7. Process for recycling phosphate, lithium and iron batteries (100), according to any one of the preceding claims, CHARACTERIZED by the fact that in the separation step (104), the plastic parts are separated by means of a sieve that has a mesh opening size of 0.1 to 4 mm.

8. Process for recycling phosphate, lithium and iron batteries (100), according to any one of the preceding claims, CHARACTERIZED by the fact that in the fluorine precipitation step (105), the addition of Ca(OH)2 or CaCh is in an amount of 0 stoichiometric and 20% excess, reaction time of up to 2.0 hours, and with a temperature between 25°C and 90°C.

9. Process for recycling phosphate, lithium and iron batteries (100), according to any one of the previous claims, CHARACTERIZED by the fact that in the lithium precipitation step (106), the addition of Na2CÜ3 is in an amount of 0 stoichiometric and 20% excess, reaction time of up to 2.0 hours, with a temperature of 20°C to 80°C, and with a yield of at least 10% lithium precipitation.

10. Process for recycling phosphate, lithium and iron batteries (100), according to any one of the previous claims, CHARACTERIZED by the fact that: the acid used in the leaching step (107) is one of sulfuric acid or citric acid, sulfuric acid being the preferred leaching agent.

11. Process for recycling phosphate, lithium and iron batteries (100), according to any one of the preceding claims, CHARACTERIZED by the fact that the leaching step (107) is carried out without the presence of an oxidizing agent.

12. Process for recycling phosphate, lithium and iron batteries (100), according to any one of the preceding claims, CHARACTERIZED by the fact that the leaching stage (107) has an acid concentration ranging from 0.2mol / L to 4.0mol / L, temperature from 25°C to 90°C, reaction time from 0.5 to 5.0 hours.

13. Process for recycling phosphate, lithium and iron batteries (100), according to any one of the previous claims, CHARACTERIZED by the fact that the solid material filtered in the leached solution filtration step (108) comprises graphite, remains of the battery's external structure, metallic copper sheets and metallic aluminum sheets.

14. Process for recycling phosphate, lithium and iron batteries (100), according to any one of the preceding claims, CHARACTERIZED by the fact that the sieving of the solid material separation step (109) is carried out with a sieve with a mesh opening size of 0.1 to 4 mm to separate the graphite from the solid material.

15. Process for recycling phosphate, lithium and iron batteries (100), according to any one of the preceding claims, CHARACTERIZED by the fact that the elutriation of the solid material separation step (109) is carried out in a conventional elutriator with the addition of water in the column in ascending flow after screening to separate the graphite, in which the external structure of the battery cells, the aluminum and copper sheets are recovered.

16. Process for recycling phosphate, lithium and iron batteries (100), according to any one of the previous claims, CHARACTERIZED by the fact that the iron separation step (110) is carried out in a pH range of 1.5 to 3.5, temperature of 25°C to 80°C, reaction time of 0.25 and 4.0 hours, preferably using Na2CÜ3 added in solid form or in solution to reach a concentration of up to 1.0mol / L of precipitating agent in the solution.

17. Process for recycling phosphate, lithium and iron batteries (100), according to any one of the preceding claims, CHARACTERIZED by the fact that in the step of removing the remaining iron (1 1 1 ), the ion exchange resin used is preferably of the aminophosphonic functional group, carried out in a batch process or, preferably, in a continuous system.

18. Process for recycling phosphate, lithium and iron batteries (100), according to any one of the previous claims, CHARACTERIZED by the fact that in the stage of removing the remaining iron (11 1) carried out in a batch process, it occurs with the addition of 0.2 to 2 kg of resin per 10 L of solution, a temperature range of 25°C to 60°C, reaction time of 0.5 to 6.0 hours.

19. Process for recycling phosphate, lithium and iron batteries (100), according to any one of the preceding claims, CHARACTERIZED by the fact that in the remaining iron removal step (1 1 1 ) carried out in a continuous system, columns filled with resin connected in series are used, with ascending or descending flow, with a flow rate of 0.5 to 5 bed volumes / hour and a temperature range of 25°C to 60°C.

20. Process for recycling phosphate, lithium and iron batteries (100), according to any one of the previous claims, CHARACTERIZED by the fact that the aluminum precipitation step (112A) is carried out in a pH range of 3.5 to 7.0, temperature of 25°C to 80°C, reaction time of 0.5 to 3.0 hours, and preferably using Na2CÜ3 in an amount of stoichiometric and 40% excess, in which precipitated aluminum is separated from the solution through filtration.

21. Process for recycling lithium iron phosphate batteries (100), according to any one of the preceding claims, CHARACTERIZED by the fact that the remaining lithium precipitation step (113) to obtain lithium in the form of Li2SO4, Li3PO4, Li2CO3, or LiOH is carried out in one of the following ways: i) crystallizing the solution at a temperature of 80°C to 110°C, reaction time of 1.0 to 5.0 hours, to obtain lithium sulfate (Li2SO4); ii) add sodium phosphate (solid or in solution) in a stoichiometric amount at 40% excess, to the solution under stirring, at a temperature of 25°C to 90°C, reaction time of 1.0 to 5.0 hours, to obtain lithium phosphate (LI3PO4); iii) add sodium carbonate to the solution under stirring, at a concentration of 50g / L to 200g / L, at a temperature of 25°C to 90°C, reaction time of 1.0 to 5.0 hours, and obtain lithium carbonate (LI2CO3); or iv) from the lithium carbonate obtained in iii), add calcium hydroxide at a concentration of 0.2g / L to 1.0g / L, at a temperature of 25°C to 90°C, reaction time of 1.0 to 5.0 hours, and obtain lithium hydroxide (LiOH).

22. Process for recycling phosphate, lithium and iron batteries (100), according to any one of the previous claims, CHARACTERIZED by the fact that it further comprises: a step for separating aluminum from the solution by electrodialysis (112B) with a cationic and anionic membrane after the step for removing the remaining iron (111), in which the electrodialysis is carried out in a range of 200mA to 400mA of electric current and a reaction time of up to 30 hours, and in which the solution concentrated in aluminum proceeds to the aluminum precipitation step (112A).

23. Process for recycling phosphate, lithium and iron batteries (100), according to any one of the previous claims, CHARACTERIZED by the fact that after the remaining lithium precipitation step (113), the solution goes through a crystallization step, in which the solution is evaporated at a temperature of 90°C to 110°C and reaction time of 1.0 to 5.0 hours, to obtain sodium sulfate crystals and return the acid used in the leaching and still present in the solution to the leaching step (107).

24. Process for recycling phosphate, lithium and iron batteries (100), according to any one of the preceding claims, CHARACTERIZED by the fact that in the steps of fluorine precipitation (105), lithium precipitation (106), leaching (107), filtration of the leached solution (108), aluminum precipitation (112A), and precipitation of remaining lithium (113), the filter used has pores of 0.1 to 4 pm.

25. Process for recycling phosphate, lithium and iron batteries (100), according to any one of the preceding claims, CHARACTERIZED by the fact that the filters used are of the paper or membrane types.

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