RECUPERAÇÃO DE LÍTIO A PARTIR DE ESCÓRIAS
Patent Information
- Authority / Receiving Office
- BR · BR
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2024-03-20
- Publication Date
- 2026-08-04
Abstract
Description
1 / 13 Lithium recovery from slag.
[0001] The present invention relates to a process for recovering Li (lithium) contained in metallurgical slags. Such slags are typically produced when Li batteries or their residue are recycled using a smelting process. Relatively noble metals, such as Cu, Co and Ni, report an alloy phase, while more easily oxidizable elements, such as Li, report a slag phase. Both phases are allowed to settle and are removed.
[0002] Due to the relative scarcity of Li, it has recently become economical to recover it from slag. Known processes employ acid leaching to dissolve the Li.
[0003] Document WO2022085222 discloses a process for recovering lithium from secondary battery material. It teaches that it is essential to ensure a mass ratio between Al and Li of 6 or less. This requirement is met by regulating the amount of Al in the slag according to different schemes. Leaching of the slag is carried out using an acidic aqueous solution. Particle diameters between 0.5 and 5 mm are preferred. Then, a purification step of the leachate is carried out, increasing its pH to up to 14 by adding an alkaline substance. The mixture is filtered and the Li in the solution is precipitated as carbonate.
[0004] Document JP2020029613 describes the combination of a reductive smelting step with an aqueous leaching step for the recovery of valuable metals in used Li-ion batteries. The leaching step is carried out on the slag prepared in the smelting step, with the aim of recovering Li in a leaching solution. The slag is leached in slightly acidified water to a pH of 5 to 7, under normal pressure and at a temperature below 100 °C. Pressure leaching is considered unnecessary. Particle diameters between 0.5 and 5 mm are preferred. The pH of the solution gradually increases to 11 or higher due to the dissolution of Li. This helps to precipitate any Ni, Co, Cu, and Fe, which are not desired in the solution. When the amount of Li is small, a water-soluble alkali can be added to the mixture to ensure a basic pH of 11 or higher. The mixture is then filtered.
[0005] According to the documents cited above, Li is leached under acidic conditions, thereby producing a soluble salt, such as LiCl or Li2SO4. This salt must be converted into insoluble Li2CO3 or LiOH, which is then precipitated. The alkaline conditions mentioned refer only to Petition 870250084305, dated 09 / 18 / 2025, pp. 75 / 94 2 / 13 subsequent purification of the solution.
[0006] It has now been found that Li in a slag can be selectively leached using specific amounts of an alkaline Ca compound. Under optimized conditions, Li leaching yields of 80% or more can be obtained. LiOH is formed during the leaching step, thus making further conversion of the lithium salt to LiOH unnecessary.
[0007] To produce battery-grade Li, the LiOH solution can be purified, for example, by impurity precipitation, ion exchange, or using selective membranes. High-purity lithium is easily obtainable using crystallization, such as evaporative crystallization to produce solid LiOH, or reactive crystallization with carbonates to produce Li2CO3.
[0008] In a first embodiment, a process is described for the recovery of Li from a metallurgical slag containing Li, comprising the following steps: - pulverization of metallurgical slag to a particle size distribution having a D50 of less than 100 µm, calculated from the cumulative volume distribution of undersized particles, in accordance with ISO 13320:2020; - contacting, in an aqueous medium, metallurgical slag containing Li with an alkaline Ca compound, supplied in quantities selected to obtain a molar ratio between the Ca in the Ca compound and Li in the slag of at least 0.75, thereby obtaining a suspension; - heating the suspension to a temperature above 80 °C for at least 30 minutes, thereby obtaining a leached suspension; and - separation of solids from liquids in the leachate suspension, thereby obtaining a leachate solution containing a larger proportion of Li and a solid residue containing Ca.
[0009] Metallurgical slag is typically obtained by recycling Li-ion batteries or their residue using smelting. Such a smelting process produces slag containing Li in amounts of at least 0.2% by weight, but more typically more than 1% by weight, or even more than 2.5% by weight. This slag is a suitable feedstock for the present process.
[0010] According to stoichiometry, one would expect that one mole of Ca would be sufficient to leach two moles of Li, resulting in a molar ratio of 0.5. Surprisingly, it was observed that, in fact, a significant excess of Ca is necessary. This excess could be quantified, resulting in a Petition 870250084305, dated 09 / 18 / 2025, pp. 76 / 94 3 / 13 lower limit of 0.75 for the molar ratio between Ca and Li. This lower limit corresponds to 150% of the stoichiometric quantity.
[0011] To allow the formation of an alloy phase and a slag phase during melting, so-called slag formers or fluxes are used. Typically, slag formers are, for example, CaO and SiO2. Notably, the CaO in the slag must be considered as non-reactive in the present Li leaching process. The specified amount of an alkaline Ca compound, such as CaO, Ca(OH)2 or CaCO3, must therefore be added in the contacting step, regardless of the Ca in the slag.
[0012] The amount of Li in metallurgical slag can be determined by chemical analysis. Those skilled in the art can then easily determine the amount of Ca compound needed in the contacting step.
[0013] The specified amount of Ca compound for this process can be added all at once or, alternatively, in stages.
[0014] The steps of contacting, heating, and solid-liquid separation, which together perform leaching, can be repeated on the solid residue to further increase the Li yield. The specified amount of Ca compound can then be distributed across the repeated contacting steps. A countercurrent flow of aqueous solution and solid residue is, by this means, particularly useful as it reduces the total water consumption while optimizing the Li leaching yield.
[0015] The process of the present invention can be operated in batch or continuous mode.
[0016] Heating and reaction time may be somewhat correlated according to generally known rules: lower temperatures may imply longer reaction times to achieve optimal Li leaching yields, while higher temperatures may increase kinetics.
[0017] By “main part” of an element is meant 50% or more of the quantity of that element that goes into the process.
[0018] In another embodiment, metallurgical slag comes from the recycling of Li-ion batteries or their residue using a pyrometallurgical smelting process. Li-ion batteries or their residue comprise spent or end-of-life batteries, production scrap or battery constituents such as electrode sheets, electrolytes, separators, lining material and materials Petition 870250084305, dated 09 / 18 / 2025, pp. 77 / 94 4 / 13 of the electrode, or pre-processed battery materials, such as "black matter," resulting in very complex waste streams.
[0019] In another method, the slag is pulverized by grinding or atomization. This ensures that the dissolution of Li occurs more quickly and completely. Comminution by grinding is a preferred option. Grinding can be carried out during the contact stage.
[0020] In another embodiment, the metallurgical slag has a particle size distribution having a D50 less than 50 µm, preferably less than 25 µm, more preferably less than 15 µm. The particle size distribution is measured by laser diffraction according to ISO 13320:2020. D50 is the particle size, in µm, by which the cumulative volumetric distribution reaches 50%. Through a small particle size, the lithium compounds are more exposed to the Ca compound in solution. Particles having a D50 of 5 to 30 µm showed excellent yields and leaching kinetics of Li. Further reducing the particle size increases the kinetics of the process, but will have only a limited impact on the overall leaching yield.
[0021] The sequence of addition of the slag, the Ca compound and the aqueous medium in the contacting step is not critical.For example, in one embodiment, the Ca compound is added to the metallurgical slag before the mixture is brought into contact with the aqueous medium.
[0022] In another embodiment, the Ca compound is added in an amount selected to have a molar ratio between the Ca in the Ca compound and the Li in the slag of 1 to 1.5, preferably 1.1 to 1.3, and more preferably 1.1 to 1. These ratios provide a good yield of Li while avoiding excessive reagent costs.
[0023] In another embodiment, the Ca compound is CaO, Ca(OH)2 or CaCO3. CaCO3 is the preferred choice, while CaO and Ca(OH)2 are even more preferred.
[0024] In another embodiment, the Ca compound is in powder form. This facilitates reactions with the aqueous medium, as well as with the slag.
[0025] In another embodiment, the contacting step is carried out using a solid-to-liquid ratio of 50 to 500 g / L. This ensures the suspension of the solids in the aqueous medium with reasonable agitation power in the contacting and heating reactor(s).
[0026] In another embodiment, the heating step is carried out at 100 to 200 °C, preferably at 110 to 150 °C. It has been found that reaction temperatures Petition 870250084305, dated 09 / 18 / 2025, pp. 78 / 94 Higher temperatures, above 100 °C, substantially increase the Li yield. Operating at temperatures below 70 °C may be feasible, but this would require an impractical reaction time to achieve the desired Li yield of at least 50%. Higher temperatures in the range of 100 °C to 200 °C are preferable for economic reasons. On the other hand, increasing the reactor temperature to more than 150 °C does not significantly improve the Li yield.
[0027] In another embodiment, the process is carried out in an aqueous medium comprising dissolved salts. For example, 1 mol / L of dissolved Na2SO4 or NaOH will raise the boiling point of the aqueous medium, allowing the heating stage to operate slightly above 100 °C, avoiding the use and costs of a pressure reactor.
[0028] In another modality, the warm-up phase is carried out for a period of 30 to 600 min, preferably for 90 to 400 min and, more preferably, for 180 to 360 min.
[0029] In another embodiment, the Ca compound is premixed with the metallurgical slag before the contact stage. For example, the Ca compound can be added during the comminution of the slag.
[0030] In another embodiment, the solid residue, obtained in the solids-liquid separation step in the leachate suspension, is ground. This is useful when the contact, heating, and solid-liquid separation steps are applied repeatedly.
[0031] In another embodiment, the metallurgical slag additionally comprises 5 to 50% by weight of Al2O3, preferably 30 to 50% by weight. Al is frequently present in metallurgical slag, since the casing of Li-ion batteries or cathode sheets are made of Al. Al is very easily oxidized and is fully absorbed into the slag.
[0032] In another embodiment, the metallurgical slag additionally comprises 2 to 50% by weight of SiO2, preferably 2 to 20% by weight, more preferably 2 to 10% by weight. SiO2 is frequently added to a metallurgical slag as a flux, reducing the melting point of the slag or making it less viscous. Si is very easily oxidized and fully disperses into the slag.
[0033] In another embodiment, the metallurgical slag additionally comprises 10 to 70% by weight of MnO, preferably 10 to 40% by weight and, more preferably, 15 to 30% by weight. Mn is frequently present Petition 870250084305, dated 09 / 18 / 2025, pp. 79 / 94 6 / 13 as an active ingredient in cathodes. It is easily oxidized and is mainly found in slag.
[0034] In another embodiment, at the contact stage, smelter fumes comprising LiF and an additional alkaline Ca compound are provided in amounts selected to obtain a molar ratio between the Ca in the additional Ca compound and the Li in the fumes of 0.25 to 0.5. The Li fumes may comprise different Li salts. Some of them, such as LiF, consume a stoichiometric amount of the Ca compound to dissolve, while most others, such as LiBr, LiCl, and Li2O, dissolve readily without any need for Ca. In contrast to the first embodiment, the additional amount of Ca to leach LiF corresponds to the expected molar ratio of 0.5. This additional amount could, however, be even lower, down to 0.25, particularly when the amount of Ca compound used to leach the Li in the slag is high, resulting in a large unreacted excess.For practical reasons, the same Ca compound is preferably chosen to leach Li from the slag and fumes.
[0035] In another embodiment, metallurgical slag containing Li obtained from a first pyrometallurgical smelting process and foundry fumes containing Li, obtained from the same or another pyrometallurgical smelting stage, are premixed, thereby obtaining a heterogeneous mixture enriched in Li.
[0036] In another embodiment, the solid residue is used as a substitute for cement. The solid residue or leaching residue is the insoluble part that remains after the execution of the process of the present invention. It can be used, at least partially, as a substitute for cement.
[0037] The following Examples illustrate the invention. Example 1: effect of temperature
[0038] Lithium slag containing 4.35 wt% Li, 21.4 wt% Al, 21.7 wt% Si, 17.6 wt% Ca, 1.12 wt% Mn, 1.30 wt% Mg, and 0.74 wt% Fe is ground to obtain a particle size distribution having a D50 of about 5 to 8 µm. 30 g of this slag, 125 mL of water, and 10.5 g of CaO are added to a pressure reactor. The molar ratio of Ca in the added CaO to Li in the slag is 1. The reactor is heated to 120 °C and maintained at this temperature for 90 minutes. The leached suspension is filtered, and the solid residue is washed and dried. A leaching solution is obtained with a Li concentration of 8.98 g / L, corresponding to a Petition 870250084305, dated 09 / 18 / 2025, pp. 80 / 94 7 / 13 yield of 75%. The elemental content of the feed, the resulting leaching solution and the solid residue is shown in Table 1. Table 1: Mass balance (g) of the leaching process carried out at 120 °C (base case) __________________________________________________________ Slag CaO Leaching solution Solid residue Li 1.31 0.98 0.33 Al 6.42 0.06 6.36 Ca 5.28 7.53 0.003 12.8 Mn 0.34 0 0.34 Si 6.51 0 6.51
[0039] This example is repeated at different temperatures. The corresponding yields of Li are shown in Table 1a. Table 1a: Li yield as a function of heating temperature Petition 870250084305, dated 09 / 18 / 2025, pp. 81 / 94 8 / 13 Temperature (°C) Li Yield (%) 70 36 80 50 120 75 150 77 200 76
[0040] Reducing the reactor temperature to 70 °C results in an inadequate Li yield of 36%. Increasing the reactor temperature to 80 °C or more significantly improves Li dissolution. Further increasing the temperature to over 120 °C or more than 150 °C has only a limited effect. Example 2: effect of the Ca / Li ratio
[0041] 30 g of ground slag according to Example 1, 125 mL of water and 15.8 g of CaO are added to a pressure reactor. The molar ratio between the Ca in the added CaO and the Li in the slag is 1.5. The reactor is heated to 150 °C and maintained at this temperature for 90 minutes. The leached suspension is filtered, and the solid residue is washed and dried. A leaching solution with a Li concentration of 9.82 g / L is obtained, corresponding to a yield of 78%. The elemental content of the feed, the resulting leaching solution, and the solid residue is shown in Table 2. Table 2: Mass balance (g) of the leaching process carried out with a Ca / Li ratio of 1.5 (base case) Li slag CaO Leaching solution Solid residue Li 1.31 1.02 0.29 Al 6.42 0.11 6.31 Ca 5.28 11.3 0.004 16.54 Mn 0.34 0 0.34 Si 6.51 0 6.51 This example is repeated using different Ca / Li ratios. The corresponding Li yields are shown in Table 2a. Petition 870250084305, dated 09 / 18 / 2025, pp. 82 / 94 9 / 13 Table 2a: Li yield as a function of the Ca / Li ratio Ca / Li Ratio Li Yield (%) 0.5 37 0.75 54 1.0 67 1.5 78
[0042] A Ca / Li ratio of 0.5 results in an inadequate Li yield of 37%. Increasing the Ca / Li ratio to 0.75 significantly improves the Li yield. The Li yield increases even further when more Ca is added. Example 3: Effect of heating time using pressure leaching
[0043] Lithium slag containing 4.1% by weight of Li, 20.1% by weight of Al, 7.0% by weight of Si, 15.5% by weight of Ca, 6.6% by weight of Mn, 1.99% by weight of Mg, and 0.90% by weight of Fe is ground to obtain a particle size distribution having a D50 of about 5 to 8 µm. 20 g of this slag, 125 mL of water, and 10.5 g of CaO are added to a pressure reactor. The molar ratio of Ca in the added CaO to Li in the slag is 1.5. The reactor is heated to 150 °C and maintained at this temperature for 270 minutes. The leached suspension is filtered, and the solid residue is washed and dried. A leaching solution with a Li concentration of 6.84 g / L is obtained, corresponding to a yield of 88%. The elemental content of the feed, the resulting leaching solution, and the solid residue is shown in Table 3. Table 3: Mass balance (g) of the leaching process carried out for 270 min (base case) Li slag CaO Leaching solution Solid residue Li 0.82 0.72 0.10 Al 4.02 0.041 3.98 Ca 3.10 7.5 0.002 10.6 Mn 1.32 0 1.32 Si 1.40 0 1.40
[0044] This example is repeated using different leaching times. The Petition 870250084305, dated 09 / 18 / 2025, pp. 83 / 94 10 / 13 corresponding Li yields are shown in Table 3a. Table 3a: Li yield as a function of leaching time Reaction time (min) Li yield (%) 30 68 45 77 90 82 180 85 270 88 360 90
[0045] Most of the Li is leached after only 30 minutes. Longer times result in improved yields. Such longer times can be useful when a lower temperature is selected or when coarser slag particles are being treated. Example 4: Effect of heating time on atmospheric pressure
[0046] Lithium slag containing 4.3% by weight Li, 16.8% by weight Al, 4.5% by weight Si, 17.7% by weight Ca, 11% by weight Mn, 1.3% by weight Mg, and 2.5% by weight Fe is ground to obtain a particle size distribution having a D50 of about 5 to 8 pm. 200 g of this slag, 1000 mL of water, and 140 g of Ca(OH)2 are added to a pressure reactor. The molar ratio between the Ca in the added Ca(OH)2 and the Li in the slag is 1.5. The reactor is heated to 90 °C and maintained at this temperature for 360 minutes. The leached suspension is filtered, and the solid residue is washed and dried. A leaching solution with a Li concentration of 4.2 g / L is obtained, corresponding to a yield of 59%. The elemental content of the feed, the resulting leaching solution, and the solid residue is shown in Table 4. Table 4: Mass balance (g) of the leaching process carried out for 270 min (base case) Li slag Ca(OH)2 Leaching solution Solid residue Li 8.6 5.1 3.5 Al 33.6 0.025 33.6 Ca 35.4 76 0.002 35.4 Mn 22 0 22 Petition 870250084305, dated 09 / 18 / 2025, pages 84 / 94 11 / 13 Li slag Ca(OH)2 Leaching solution Solid residue Si 8.8 0 8.8
[0047] This example is repeated using different leaching times. The corresponding Li yields are shown in Table 4a. Table 4a: Li yield as a function of leaching time Reaction time (min) Li yield (%) 360 59 720 72
[0048] Most of the Li is leached after 360 minutes at 90 °C. Longer times result in improved yields. Compared to Example 3, lower temperatures require, as expected, longer reaction times to leach most of the Li. Example 5: effect of particle size distribution
[0049] Li slag containing 4.41 wt% Li, 19.8 wt% Al, 6.48 wt% Si, 23.8 wt% Ca, 0.93 wt% Mn, 1.30 wt% Mg, and 0.81 wt% Fe is ground to a particle size distribution having a D50 of approximately 9.8 µm. 200 g of this slag, 1 L of water, and 107 g of CaO are added to a pressure reactor. The molar ratio of Ca in the added CaO to Li in the slag is 1.5. The reactor is heated to 150 °C and maintained at this temperature for 10 hours. The leached suspension is filtered, and the solid residue is washed and dried. A leaching solution with a Li concentration of 7.5 g / L is obtained, corresponding to a yield of 85%. The elemental content of the feed, the resulting leaching solution, and the solid residue is shown in Table 5. Table 5: Mass balance (g) of the leaching process carried out on slags Having a D50 of 9.8 pm (base case) Li slag CaO Leaching solution Solid residue Li 8.82 7.5 1.32 Al 39.6 0.4 39.2 Ca 47.6 76.5 0.05 124.1 Petition 870250084305, dated 09 / 18 / 2025, pages 85 / 94 12 / 13 Li slag CaO Leaching solution Solid residue Mn 1.86 0 1.86 Si 13.0 0 13.0
[0050] This example is repeated using different grinding conditions, producing slags with different particle size distributions. These are characterized primarily by their D50. The corresponding Li yields are shown in Table 5a. Table 5a: Li yield as a function of particle size distribution D50 (pm) Li Yield (%) 7.61 93 9.8 85 11.2 77 24.1 75 95.5 52
[0051] With a D50 of 95.5 pm, a marginally acceptable 52% of the Li dissolves. Further decreasing the particle size to less than 50 pm considerably increases the Li yield. Example 6: Illustration of a two-stage leaching process.
[0052] 30 g of ground slag according to Example 1, 125 mL of water and 13.2 g of CaO are added to a pressure reactor. The molar ratio between the Ca in the added CaO and the Li in the slag is 1.25. The reactor is heated to 150 °C and maintained at this temperature for 90 minutes. The first leached suspension is filtered, and the solid residue is washed and dried. A first leaching solution was obtained having a Li concentration corresponding to a yield of 78%.
[0053] The dried leaching residue, 165 mL of H2O, and 2.6 g of CaO are added to a pressurized reactor. This increases the total molar ratio between the Ca in the added CaO and the Li in the slag to 1.5. The reactor is heated to 150 °C and maintained at this temperature for 90 minutes. The second leached suspension is filtered, and the solid residue is washed and dried. A second leaching solution containing Li was obtained, raising the total Li yield of the process to 90%. The Petition 870250084305, dated 09 / 18 / 2025, pages 86 / 94 13 / 13 final residue is depleted in Li. Table 6: Mass balance (g) of the two-stage leaching process Li slag CaO First leaching solution Second leaching solution Final residue Li (g) 1.31 1.02 0.16 0.13 Al (g) 6.42 0.05 0.01 6.36 Ca (g) 5.3 11.3 0.003 0.02 16.6 Mn (g) 0.34 0 0 0.34 Si (g) 6.51 0 0 6.51
[0054] The yield of Li can be improved by repeating the leaching operation on the solid residue. The total amount of Ca added can then be distributed across the different leaching stages. Petition 870250084305, dated 09 / 18 / 2025, pp. 87 / 94
Claims
1 / 3 CLAIMS 1. Process for recovering Li from a metallurgical slag containing Li, characterized by comprising the steps of: - pulverization of the metallurgical slag to a particle size distribution having a D50 of less than 100 µm, calculated from the cumulative volume distribution of undersized particles, in accordance with ISO 13320:2020; - contacting, in an aqueous medium, the metallurgical slag containing Li with an alkaline Ca compound, supplied in quantities selected to obtain a molar ratio between the Ca in the Ca compound and Li in the slag of at least 0.75, thereby obtaining a suspension; - heating the suspension to a temperature above 80 °C for at least 30 min, thereby obtaining a leached suspension; e - separation of solids from liquids in the leachate suspension, thereby obtaining a leachate solution containing a larger proportion of Li and a solid residue containing Ca.
2. Process according to claim 1, characterized in that the metallurgical slag comes from the recycling of Li-ion batteries or their residue.
3. Process, according to claim 1 or 2, characterized in that the pulverization of the slag is carried out by comminution or atomization.
4. Process according to claim 3, characterized in that the comminution is carried out by grinding, and in which the grinding is carried out during the contacting step.
5. Process, according to any one of claims 1 to 4, characterized in that the metallurgical slag has a particle size distribution having a D50 below 50 µm, preferably below 25 µm, more preferably below 15 µm, calculated from the cumulative undersized distribution by volume, in accordance with the standard Petition 870250084305, dated 18 / 09 / 2025, pp. 91 / 94 2 / 3 ISO 13320:2020.
6. Process, according to any one of claims 1 to 5, characterized in that the Ca compound is provided in an amount selected to obtain a molar ratio between the Ca in the Ca compound and the Li in the slag of 1 to 1.5, preferably 1.1 to 1.
3.
7. Process according to any one of claims 1 to 6, characterized in that the Ca compound is CaO, Ca(OH)2 or CaCO3.
8. Process, according to any one of claims 1 to 7, characterized in that the contacting step is carried out using a solid-to-liquid ratio of 50 to 500 g / L.
9. Process, according to any one of claims 1 to 8, characterized in that the heating step is carried out at a temperature of 100 to 200 °C, preferably 110 to 150 °C.
10. Process, according to any one of claims 1 to 9, characterized in that the heating stage is carried out for a period of 30 to 600 min, preferably 90 to 400 min, and most preferably 180 to 360 min.
11. Process, according to any one of claims 1 to 10, characterized in that the Ca compound is premixed with the metallurgical slag before the contacting step.
12. Process, according to any one of claims 1 to 11, characterized in that the solid residue is ground.
13. Process, according to any one of claims 1 to 12, characterized in that the metallurgical slag additionally comprises 5 to 50% by weight of Al2O3, preferably 30 to 50% by weight.
14. Process, according to any one of claims 1 to 13, characterized in that the metallurgical slag additionally comprises 2 to 50% by weight of SiO2, preferably 2 to 20% by weight, more preferably 2 to 10% by weight. Petition 870250084305, dated 09 / 18 / 2025, pp. 92 / 94 3 / 3 15. Process, according to any one of claims 1 to 14, characterized in that the metallurgical slag additionally comprises 10 to 70% by weight of MnO, preferably 10 to 40% by weight and, more preferably, 15 to 30% by weight.
16. Process, according to any one of claims 1 to 15, characterized in that, in the contacting step, melting fumes comprising LiF, and an additional alkaline Ca compound are provided in quantities selected to obtain a molar ratio between the Ca in the additional Ca compound and the Li in the fumes of 0.25 to 0.
5. Petition 870250084305, dated 09 / 18 / 2025, pp. 93 / 94