MANGANESE SPINEL DOPED WITH MAGNESIUM, CATHODE MATERIAL COMPRISING THE SAME, METHOD FOR PREPARING THEREOF AND LITHIUM ION BATTERY COMPRISING SUCH SPINEL

Abstract

The present invention relates to the field of technologies for powering portable electronic parts, electrical tools, hybrid and electric vehicles and storage systems for renewable energy sources. Specifically, the invention relates to lithium ion batteries, more specifically to an active compound useful for manufacturing the cathodes in said lithium ion batteries. Even more specifically, the present invention relates to a manganese spinel doped with magnesium, a cathodic material comprising the same, the method for preparing thereof and lithium ion batteries comprising such spinel.

Claims

1. Manganese spinel preparation method doped with magnesium formula LiMg.sub.0.05Mn.sub.1.95O.sub.4 comprising: synthesize pure spinel by means of the sol-gel method assisted by ultrasound, using lithium and manganese raw materials: Li.sub.2CO.sub.3, Mn(CH.sub.3COO).sub.2 and Mg(OH).sub.2, following the following steps: a) prepare a first solution corresponding to the dissolution in stoichiometric quantities of the metal ion precursors, Li.sub.2CO.sub.3, Mn(CH.sub.3COO).sub.2 and Mg(OH).sub.2, in distilled water at room temperature; b) preparing a second solution corresponds to the dissolution of the organic precursors ethylene glycol and citric acid in distilled water; c) mixing the solutions obtained in steps a) and b) under continuous stirring; d) adjusting the pH of the solution resulting from step c) between a range of 7 to 7.5; e) subjecting the sol obtained in step d) to sonication and then heating to evaporate the water and obtain a gel, and subsequently, dry the same; f) grinding and calcining the synthesis precursor obtained in step e) and thus obtaining the spinel doped with magnesium, (LiMg.sub.xMn.sub.2xO.sub.4).

2. The method of claim 1, comprising Li.sub.2CO.sub.3 with battery grade >99.5% as one of the raw materials.

3. The method of claim 1, wherein in step d), the pH is adjusted by adding ammonium hydroxide.

4. The method of claim 1, wherein in step e), the sonication is carried out using an ultrasonic bath.

5. The method of claim 1, wherein in step e) it is heated up to 80 C.

6. The method of claim 1, wherein in step e) the drying is performed at 175 C.

7. The method of claim 1, wherein the calcination of step f) is carried out in an air atmosphere at 500 C. for 4 h and at 750 C. for 12 h.

8. Method of preparing cathodic coating of cells for lithium ion battery using a manganese spinel doped with magnesium of formula LiMg.sub.xMn.sub.2xO.sub.4, comprising: a) preparing a suspension consisting of a mixture of 90% by weight of the Mg-doped spinel prepared according to claim 1, 5% by weight of carbon black as a conductive additive and 5% by weight of PVDF (polyvinylidene difluoride) as a binder in NMP solution (n-methyl pyrrolidone); b) mixing the suspension prepared in step a) minimizing agglomeration and ensuring homogeneity by adding the different constituents of the electrode, LiMg.sub.0.05Mn.sub.1.95O.sub.4 cathodic active material one by one conductive additive and binder; c) depositing the suspension obtained in b) on Al paper and dry to fix it and obtain cathodic coating; d) optionally calendering the cathodic coating is performed to improve the adhesion of the cathodic suspension on the Al paper and to establish the porosity of the coating; e) vacuum dry to remove all water content.

9. Manganese spinel doped with magnesium formula LiMg.sub.0.05Mn.sub.1.95O.sub.4 comprising a diffractogram with eight characteristic peaks at angles 2 of 18.45, 35.66, 37.28, 43.33, 47.42, 57.27, 62.92, 66.19 for CuKa radiation, corresponding to the crystal planes (1 1 1), (3 1 1), (2 2 2), (4 0 0), (3 3 1), (5 1 1), (4 4 0) and (5 3 1), respectively.

10. The spinel of claim 9, wherein the active powders of said spinel have a morphology of the spherical type and an average particle size of 125 nm.

11. The spinel of claim 9 wherein the oxidation state of manganese is 3.6.sup.+.

12. The spinel of claim 9, wherein it has a cubic cell Fd3m with a cell parameter of a=8.355 .

13. The spinel of claim 9, wherein it has a particle size of approx. 125 nm.

14. The spinel of claim 9 wherein that it has a density of 4.2 gcm.sup.1.

15. Use of the magnesium doped spinel of claim 9 to manufacture a lithium ion battery.

16. Lithium-ion battery comprising the magnesium doped spinel of claim 9.

17. The battery of claim 16 wherein it is composed of unit cells type pouch (prismatic cell of malleable shell of polymer/aluminum) of 4 Ah capacity and 12 mm thick.

18. The battery of claim 16 wherein it is composed of a positive (positive) electrode of manganese oxide lithium doped with magnesium (LiMg.sub.0.05Mn.sub.1.95O.sub.4) with spinel structure and by a negative electrode (anode) of graphite, (G), with layered structure.

19. The battery of claim 17 wherein said lithium ion pouch cell of 4 Ah capacity comprises 23 double coating electrodes, including 12 positive electrodes and 11 negative electrodes; and also 2 negative single coating electrodes, where the electrodes are arranged alternately, starting and ending with a negative electrode of simple coating.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0040] FIG. 1 shows the configuration of a coin-type cell CR2032.

[0041] FIGS. 2A-2C show an EDS analysis by color mapping for manganese spine's: FIG. 2A shows commercial spinel. FIG. 2B shows pure spinel. FIG. 2C shows spinel doped with Mg. Color description: O=yellow color, Mn=red color and Mg=green color.

[0042] FIGS. 3A-3C show SEM images of manganese spinels FIG. 3A shows commercial spinel. FIG. 3B shows pure spinel. FIG. 3C shows spinel doped with Mg.

[0043] FIGS. 4A-4C show X-ray diffraction patterns of manganese spinels. FIG. 4A shows spinel to commercial. FIG. 4B shows pure spinel. FIG. 4C shows spinel doped with Mg.

[0044] FIGS. 5A-5B: FIG. 5A shows curves of discharge capacity with the number of cycles, FIG. 5B shows impedance spectra of cycles 1 and 100, for a state of 100% loading, of the commercial, pure manganese spinels and commercial manganese spinel doped with Mg.

[0045] FIG. 6 shows sizing drawings of the electrodes and positive and negative terminals.

[0046] FIG. 7 shows sizing planes of the pouch type cell of 4 Ah capacity.

[0047] FIG. 8 shows sizing drawings of the 10 Ah capacity lithium-ion battery module.

DETAILED DESCRIPTION OF THE INVENTION

[0048] The present invention is related to a manganese spinel doped with magnesium (LiMg.sub.0.05Mn.sub.1.95O.sub.4), cathodic material comprising the same, method of preparation and use in lithium ion batteries.

[0049] The evaluation of the electrochemical performance of a Mg-doped Mn spinel, LiMg.sub.0.05Mn.sub.1.95O.sub.4, was performed on a laboratory scale in coin 2032-type cells, composed of a positive electrode of LiMg.sub.0.05Mn.sub.1.95O.sub.4, a metallic lithium negative electrode, a polymeric separator and an aprotic electrolyte of LiPF.sub.6. The structural and electrochemical properties of the material of the invention (Mg-doped Mn spinel, (LiMg.sub.0.05Mn.sub.1.95O.sub.4) were compared with a pure spinel and a commercial spinel. The results showed that the spinel doped with Mg, presents better electrochemical performance and better structural properties compared to pure spinel and commercial spinel.

[0050] Based on the promising electrochemical results obtained in the coin type cells, a prototype of a 10 Ah capacity lithium ion battery module was developed, consisting of individual pouch cells, composed of single and double LiMg.sub.0.05Mn.sub.1.95O.sub.4 coated cathodes, double-coated graphite anodes, a polymeric separator and aprotic electrolyte of LiPF.sub.6. At the present time, commercial solutions for the LiMn.sub.2O.sub.4 are not known with characteristics similar to those proposed in the present invention.

[0051] The ultrasound-assisted sol-gel synthesis method that was used to prepare the spinel doped with Mg, proved to be efficient for the preparation of active materials, applied to lithium ion batteries, with homogeneous morphology and particle size in nanometric scale. The doping with Mg in the manganese spinelwithout consent with any theory, would have increased the average oxidation state of the manganese, which increased the electrical conductivity of the cathode material, and on the other hand, does not modify the symmetry of the crystalline cell. Manganese spinel doped with magnesium proved to possess physical, chemical and electrochemical properties superior to commercial spinel and pure spinel. The electrochemical performance of manganese spinel doped with Mg, especially during cycling tests, it can be significantly improved with the optimization of a synthesis method and a heating treatment.

Example 1: Preparation of Manganese Spinel Doped with Magnesium

[0052] Pure spinel (LiMnO.sub.4) and spinel doped with Mg (LiMg.sub.0.05Mn.sub.1.95O.sub.4) were synthesized by means of the sol-gel method assisted by ultrasound. For the synthesis of manganese spine's, lithium and manganese raw materials were used: Li.sub.2CO.sub.3 (battery grade >99.5%, RockwoodChile) and Mn(CH.sub.3COO).sub.2 (>99%, Sigma Aldrich), respectively; in addition to the addition of Mg(OH).sub.2 (99%, Fluka Analytical) for the spinel doped with magnesium.

[0053] For the synthesis, two aqueous solutions were prepared. The first solution corresponds to the dissolution in stoichiometric quantities of the precursors of metal ions, Li.sub.2CO.sub.3 and Mn(CH.sub.3COO).sub.2 for the pure spinel and Li.sub.2CO.sub.3, Mn(CH.sub.3COO).sub.2 and Mg(OH).sub.2 for the spinel doped with Mg, in distilled water at room temperature and the second solution corresponds to the dissolution of the organic precursors ethylene glycol and citric acid in distilled water. Both aqueous solutions were mixed under continuous agitation. The pH of the resulting solution was adjusted between a range of 6 to 6.5 by adding ammonium hydroxide, thereby obtaining a sol. The sol was subjected to sonication for 2.5 hours using an ultrasound bath and then heated to 80 C. to evaporate the water content and obtain the gel. Subsequently, the gel was dried in a muffle at 170 C. for 12 h. The dry gel or synthesis precursor obtained was ground in an agate mortar and sieved for subsequent Thermogravimetric (TG) analysis. Using this technique, the optimal time/temperature programming for the heat treatment of the synthesis method was determined. Finally, the powders of the synthesis precursor were calcined in air atmosphere at 500 C. for 4 h and at 750 C. for 12 h to finally obtain the pure manganese spinel (LiMn.sub.2O.sub.4) and the spinel doped with magnesium, (LiMg.sub.0.05Mn.sub.1.95O.sub.4).

Example 2 Preparation of Cathodic Coatings

[0054] For the manufacture of the cathodic coatings, it was prepared a suspension consisting of a mixture of 90% by weight of cathodic active material [pure manganese spinel (LiMn.sub.2O.sub.4) or spinel doped with Mg (LiMg.sub.0.05Mn.sub.1.95O.sub.4) or commercial spinel (Li.sub.1.16Mn.sub.1.84O.sub.3.996S.sub.0.004), 5% by weight of carbon black as a conductive additive and 5% by weight of PVdF (polyvinylidene difluoro) as a binder in NMP solution (n-methyl pyrrolidone). The mixing process of the coating suspension was carried out in a paddle mixer under static vacuum conditions (=0.1 atm) to minimize water contamination in the suspension. The different constituents of the positive electrode, cathodic active material, conductive additive and binder were added one by one to minimize agglomeration and achieve homogeneity of the suspension.

[0055] The suspension obtained was deposited on Al paper, as a current collector, to perform the cathodic coating and then subjected to a pre-drying process in the presence of air for 12 hours, to fix the cathode cover on the current collector.

[0056] Next, a calendering of the cathodic coating was carried out to improve the adhesion of the cathodic suspension on the aluminum foil and establish the porosity of the coating according to the following expression:

=1V.sub.h/V.sub.s

[0057] wherein VI, is the volume of the wet cathodic coating and V.sub.s is the volume of the dry cathodic coating. Finally, the cathodic coating was subjected to a final vacuum drying process for 12 h, in order to eliminate all the water content. The completely dry cathodes were cut in circles with a diameter of 9/16 (1.43 cm) Table 1 details the characteristics of the prepared cathodes.

TABLE-US-00001 TABLE 1 Formulation and loading parameters of the cathodes used in CR2032 cells Description Characteristics Cathodic active Material 90% wt Binder 5% wt PVDF Conductor Additive 5% wt carbon black Coating Area 1.60 cm.sup.2 Coating Density 6.25 mg cm.sup.2 Al current collector 15 m Coating thickness 100 m Porosity 35%

Example 3: Characterization of Physical and Chemical Properties

[0058] The physical and chemical properties of the synthesized cathode materials and commercial material were determined by applying the following characterization techniques: [0059] Solid Picnometry, to determine the apparent density of the synthesized cathode active compounds and the commercial product. [0060] Scanning Electron Microscopy with X-ray Dispersion Spectroscopy detector (SEM-EDS, TESCAN, Vega 3 LMU), to study the morphology, homogeneity, particle size on a microchrome scale and elemental composition of pure spinel, spinel doped with Mg and commercial spinel. [0061] Atomic Force MicroscopyRaman (AFM RAMAN, WITec, alpha300), to determine the particle size of the cathode materials synthesized in the nanometer scale. [0062] Diffraction of X-rays for crystalline powder (DRX, Bruker, D8 Advance-A25) using Cu Ka radiation, to determine and compare the structural parameters and identify the phases, structures and crystalline defects of the synthesized spinel and commercial spinel.

[0063] Electrochemical Measurements

[0064] To evaluate the electrochemical performance of the cathode materials, CR2032 coin-type lithium ion cells were manufactured. The coin cells (FIG. 1) consist of a cathode, a metallic lithium anode, a polymeric separator and 1M LiPF.sub.6 electrolyte in EC:DMC:EMC (1:1:1 by weight). The cells were assembled in a glovebox in Argon controlled atmosphere (H.sub.2O, O.sub.2<2 ppm), to minimize the effect of moisture and oxygen. [0065] Cycling tests (Battery Analyzer, BST8-WA), coin cell load/unload tests were performed according to the CC-VC protocol (constant current-constant voltage). The activation procedure of the cells was carried out between 3.0 V and 4.8 V (versus Li+/Li) at a constant current of C/10 for 3 cycles. The extended cycling tests were performed between 3.0 V and 4.4 V (versus Li+/Li) at a constant current of C/3 per 100 cycles. The cycling protocol is detailed in Table 2. [0066] Impedance measurements (Autolab, PGSTAT302N), the measurement of the electrochemical impedance of the coin 2032 cells was carried out in a range of 20 cycles of charge/discharge, using a frequency range of 100 kHz to 10 mHz with a signal amplitude of 5 mV for a state of charge of 100%, 50% and 0%.

TABLE-US-00002 TABLE 2 Cycling test protocol Protocol of cycling tests Number of Range of Velocity of constant cycles Voltage current Cycles of activation 3 3.0 V-4.8 V C/10 Succesive cycles 100 3.0 V-4.8 V C/3

[0067] Comparative analysis between the commercial spinel and spinel doped with Mg of the invention, elemental chemical analysis and bulk density

[0068] The stoichiometries of the commercial, pure, magnesium-doped manganese spinels of the invention were elucidated from the elemental compositions provided by the EDS measurements, as shown in Table 3.

[0069] The average oxidation state of the manganese in each oxide with spinel structure, whether commercial or pure or doped with magnesium (Table 3), was determined by the charge balance of its different constituent elements based on the electroneutrality of each molecule. spinel oxide,

TABLE-US-00003 TABLE 3 Stoichiometries of manganese spinels, commercial, pure and doped with Mg, calculated from the EDS measurements Commercial LMO Pure LMO Mg doped LMO Description EDS atomic Molar EDS atomic Molar EDS atomic Molar Element percent (%) ratio percent (%) ratio percent (To) ratio Mn 31.51 1.840 33.62 2.0 32.25 1.95 O 68.42 3.996 66.38 4.0 66.93 4.05 S 0.07 0.004 Mg 0.83 0.05 Total 100 100 100 Stoichiometry Li.sub.1.15Mn.sub.1.84O.sub.3.996O.sub.0.004 LiMn.sub.2O.sub.4 LiMg.sub.0.05Mn.sub.1.95O.sub.4 Average 37.sup.+ 3.5.sup.+ 3.6.sup.+ Oxidation state of Mn

[0070] The elemental quantification of the commercial spinel (Table 3) showed the presence of sulfur in small amounts and an excess in the concentration of lithium. The commercial spinel has a co-doped crystalline structure; on the one hand, cationic doping with lithium ions that partially replace the manganese content, allowing to obtain as a resultwithout consent with any theory, an increase in the average oxidation state, high electrical conductivity and greater load capacity of the active material. On the other hand, anodic doping with sulfur ions that partially replace the oxygen concentration. Without consenting to any theory, the addition of sulfur ions would improve the structural stability of the spinel and reduce/eliminate the dissolution of Mn at high potentials, because sulfur would form stronger MnS bonds in comparison to those formed by oxygen OS. An exact stoichiometric ratio of 1:2:4 for Li:Mn:O was evidenced for the pure spinel (Table 3) synthesized by the sol-gel method assisted by ultrasound.

[0071] Regarding manganese spinel doped with Mg, the elemental analysis (Table 3) showed the presence of a spinel with Mg cationic doping. Without consenting to any theory, the small amounts of magnesium ions would replace partially the manganese content in the structure of the spinel; which would result in a higher average oxidation state compared to pure spinel, high electrical conductivity and greater structural stability. The EDS compositional analysis, by elementary mapping using false color images (FIGS. 2A-2C), shows a homogeneous distribution of the main components of the three manganese spinels: commercial spinel, pure spinel and spinel doped with Mg, respectively. The measurement of the apparent density of the commercial spinel and synthesized spinels (pure and doped with Mg) was carried out by means of pycnometry, using distilled water at room temperature, as shown in Table 5.

[0072] Particle Size and Morphology

[0073] FIGS. 3A-3C show the SEM images of the commercial manganese spinel, pure spinel and spinel doped with magnesium, respectively. FIG. 3A shows that powders of active material of the commercial spinel are composed of agglomerated particles with an average diameter of 18.5 m, which in turn are composed of fine particles with an average diameter of 500 nm. The agglomerated particles have an irregular morphology and a wide dispersion in the particle size distribution (particles of inhomogeneous size); on the other hand, it can be observed that each fine particle presents a homogeneous morphology of the cubic type, typical of the crystalline structure of the Mn spinels.

[0074] FIGS. 3B and 3C show the powders of the cathode materials synthesized via sol gel assisted by ultrasound: pure spinel and spinel with Mg doping, respectively. In both images, it can be seen that the powders are composed of fine particles of morphology and homogeneous size, properties that are attributed to the synthesis method. In both active powders a morphology of the spherical type is demonstrated and with an average particle size of 125 nm, this last measurement was made by Atomic Force Microscopy (AFM).

[0075] Crystal Structure

[0076] FIGS. 4A-4C show the X-ray diffraction patterns of the spinels analyzed. The diffraction branches present eight characteristic peaks at 2 angles and their corresponding crystal planes as shown in Table 4.

TABLE-US-00004 TABLE 4 Characteristic peaks of X-ray diffraction patterns recorded for manganese spinels, commercial, pure and doped with magnesium. Description No. of characteristics Commercial LMO Pure LMO Mg doped LMO peaks 2 angles Crystal plane 2 angles Crystal plane 2 angles Crystal plane 1 18.44 (1 1 1) 18.52 (1 1 1) 18.45 (1 1 1) 2 35.67 (3 1 1) 35.69 (3 1 1) 35.66 (3 1 1) 3 37.31 (2 2 2) 37.36 (2 2 2) 37.28 (2 2 2) 4 43.35 (4 0 0) 43.37 (4 0 0) 43.33 (4 0 0 ) 5 47.47 (3 3 1) 47.50 (3 3 1) 47.42 (3 3 1) 6 57.36 (5 1 1) 57.37 (5 1 1) 57.27 (5 1 1) 7 63.00 (4 4 0) 62.99 (4 4 0) 62.92 (4 4 0) 8 66.27 (5 3 1) 66.21 (5 3 1) 66.19 (5 3 1)

[0077] As a result of the refinement of the X-ray patterns, by means of the Rietveld method, it was determined that the three spinels have a crystalline structure with cubic symmetry and spatial group Fd3m. In addition, it was verified that the co-doping with sulfur-lithium, for the commercial spinel, and the doping of magnesium, for the doped spinel, do not modify the crystalline structure. Regarding the cell parameters, it was evidenced that the pure spinel has a smaller cell dimension compared to the commercial spinel and the spinel doped with Mg, which have a similar cell dimension. The small increase in length of the commercial spinel cell parameter, co-doped with sulfur and lithium, compared to pure spinel, is attributed to the incorporation of the sulfur ion (S.sup.2) in the crystalline structure of the manganese spinel; this is due to the fact that the sulfide ion has a greater ion radius with respect to the oxygen ion (O.sup.2), besides forming stronger bonds with manganese that improve the structural stability of the manganese spinel. In contrast, the increase in the length of the spinel cell parameter doped with Mg is attributed to the substitution of the Mn.sup.3 ion by the Mg.sup.2+ ion, and that it has a greater ion radius than the Mn.sup.4+ ion. The monovalent oxidation state of the Mg.sup.2+ ion remains unchanged during the process of intercalation and de-interleaving of the lithium ion in a way that reduces the corresponding effects of expansion and contraction of the crystalline cell, improving the structural stability of the manganese spinel during cycling at temperatures in environmental and high conditions.

[0078] Table 5 shows the data obtained from the characterization of the physical and chemical properties of manganese spinels: commercial spinel Li.sub.1.15Mn.sub.1.84O.sub.3.996O.sub.0.004, pure spinel and spinel doped with Mg (LiMg.sub.0.05Mn.sub.1.95O.sub.4).

TABLE-US-00005 TABLE 5 Data on the physical and chemical properties of commercial manganese spinels, pure spinel and spinel doped with magnesium Description Commercial LMO Pure LMO Mg doped LMO Particle size (nm) 500 ~125 ~125 Density (gcm.sup.1) 4.23 4.23 4.02 Crystal system Cubic Cubic Cubic Spatial group Fd3m Fd3m Fd3m Cell Parameter () 8.345 8.341 8.355

[0079] Cycling and Impedance Tests

[0080] After the 100 cycles of loading/unloading the coin cells assembled with the cathodes of the commercial manganese spinel and the synthesized spinel of the invention, the processing of the cycling data, as shown in FIG. 5A, showed that the cathode manufactured with the manganese spinel doped with Mg of the invention, has a higher initial load capacity compared to pure spinel (5.6% more) and commercial spinel (13% more). Although, the cathode manufactured with the commercial spinel has a better load retention in the cycle, the load capacity of the spinel doped with magnesium is always above the load capacity of the commercial spinel and with the increase of the number of cycles the loss of capacity, stabilizes and shows a linear behavior. On the other hand, the pure spinel showed a lower performance in cycling compared to the commercial spinel and the spinel doped with Mg. However, it has a higher load capacity compared to the commercial cathode, however, after 100 cycles its capacity decreases compared to the spinel doped with Mg and the commercial spinel. Regarding the tests of measure measured during cycles 1 and 100 for a state of charge of 100% (FIG. 5B). It was evidenced that the cathode manufactured with the commercial manganese spinel presents high values of impedance in comparison to the cathode synthesized by the sol-gel method assisted by ultrasound and doped with Mg according to the invention. This effect is mainly attributed to the particle size of the active material, because a smaller particle size increases the chemical reactivity of the material during the electrochemical loading and unloading reactions. The synthesis method used to obtain the pure spinel and the spinet doped with Mg, guarantees the formation of fine and homogeneous particles in nanometric scale, this property is an advantage compared to the commercial spinet which is composed of particles in scale micrometer and therefore with less chemical reactivity.

[0081] The impedance value of the cathode of the invention, after 100 cycles was 49% lower compared to the commercial cathode of manganese spinet. This difference should be due to no theory, low particle size, high chemical reactivity and high average oxidation state of manganese, which increases the electrical conductivity of the material and is attributed to the incorporation of magnesium ions in the structure of the manganese spinet.

[0082] Table 6 shows the results obtained from the stereochemical measurements for the commercial spinet and the synthesized spinet.

TABLE-US-00006 TABLE 6 Data of the electrochemical measurements of commercial manganese spinel (LMO com), pure spinel (pure LMO) and magnesium doped spinel of the invention Description Commerial LMO Pure LMO Mg doped LMO Initial capacity 106.36 113.33 120.00 (mAh g 1) Final capacity 101.82 94.44 105.60 (mAh g 1) Average coulombic 98.56 97.75 98.44 efficiency (%) Capacity retention 95.73 83.33 87.96

Example 4: Design of the Prototype of a 10 Ah Capacity Lithium-Ion Battery Module

[0083] For the design of the lithium ion battery module with the cathodic material developed based on the material of the present invention, a program developed in Excel software, called BatPac v2.2, was used. This tool provides necessary data for the design and dimensioning of the electrodes, cells, modules and packs that make up a complete lithium ion battery, this according to the energy and power criteria required by the designer.

[0084] Table 7 shows the design criteria of the lithium ion battery module used in the BatPac v2.2 tool.

TABLE-US-00007 TABLE 7 Design criteria for lithium on batteries Battery Type Ev.sup.1 SOC.sup.2 to nominal potency, % 20 Potency Duration, s 10 Range of SOC to utilizable energy, % 10-95 Cell thickness, mm 12 .sup.1EV = Electric vehicles .sup.2SOC = State of Charge

[0085] In this way, referring to the design criteria (Table 7) and the initial experimental parameters required, the Excel tool was executed with the following specifications: [0086] The type of battery selected for the simulation, corresponds to a lithium ion battery applied to electric vehicles, composed of unit cells type pouch (prismatic cell of malleable polymer/aluminum housing) of 4 Ah capacity and 12 mm thickness, with a positive electrode length/width ratio equal to 2.2 and a usable energy range of 85%. [0087] The selected system corresponds to a battery composed of the positive electrode (cathode developed based on the material of the present invention) of lithium manganese oxide doped with magnesium, (LiMg.sub.0.05Mn.sub.1.95O.sub.4) (LMO-Mg), with spinel structure and by a negative electrode (anode) of graphite, (G), with layered structure. [0088] The initial input parameters correspond to experimental measurements recorded in coin type cells (rigid metal shell button cell in the form of a disk) CR2032, corresponding to the selected system LMO-Mg/G.

[0089] The data obtained from the simulation show that to manufacture a lithium ion pouch cell, with an LMO-Mg/G capacity of 4 Ah, 23 double-coated electrodes (12 positive electrodes and 1 negative electrodes) and 2 electrodes are required. Simple negative coating. The arrangement of the electrodes is alternately, starting and ending with a negative electrode of simple coating.

[0090] FIG. 9 shows the sizing planes of the positive electrode, constituted by a manganese spinel cover doped with magnesium deposited on an Al current collector, and negative electrode, constituted by a graphite cover deposited on a current collector of Cu; as well as the planes of the positive terminals of Al and negative of Ni. For the manufacture of the lithium-ion battery module, the parallel connection of three individual cells is necessary to reach a capacity of 10 Ah. The three cells are soldered by their positive terminals of Al and negative of Ni, respectively. The end of each terminal of the module is soldered to a copper buss (buss); such connectors will be used for the final installation of the positive and negative terminals of the module.

[0091] A better detail of the parallel connection of the cells can be seen in FIG. 11, which shows the sizing drawings of the 10 Ah lithium-ion battery module.