The present application claims priority to Taiwan Patent Application No. 109126389 filed Aug. 4, 2020 and entitled “A METHOD FOR THE FABRICATION OF A HYBRID SOLID ELECTROLYTE MEMBRANE, AND AN ALL-SOLID-STATE LITHIUM BATTERY USES THE MEMBRANE,” which is hereby incorporated by reference in its entirety.
This invention relates to a method for the fabrication of a LaZrGa(OH)x metal hydroxide precursor, the fabrication of an ion-doped all-solid-state lithium-ion conductive material with lithium ionic conductivity using the precursor, and the fabrication of a free standing double layered and triple layered organic-inorganic hybrid solid electrolyte (hereinafter called “HSE”) membrane using the all-solid-state lithium-ion conductive material. The hybrid solid electrolyte membrane is further utilized in an all-solid-state lithium battery.
Lithium-ion batteries are often used for electrical storage or powered devices, such as consumer electronics and transportation facilities, due to the high open circuit voltage, high energy density, fast charge-discharge rate, long lifetime of charge-discharge cycle, low self-discharge and light weight. However, volatile and flammable liquid electrolyte may highly affect the safety of lithium-ion batteries. After undergoing several charge-discharge cycles, other than the risk of overheat, combustion and even explosion, the problem of internal short circuit of batteries due to acicular lithium-dendrite formation may also arise easily.
Though an all-solid-state lithium battery using a solid electrolyte membrane may effectively prevent the safety problems such as electrolyte leakage and combustion or explosion, other problems, including the lithium-dendrite formation, the high interfacial resistance due to the poor contact between the solid electrolyte membrane and the electrode, and the generally low conductivity (around 10−7 S cm−1) under room temperature (25° C.), still exist, which lead to a bad overall battery performance.
Therefore, regarding the current lithium batteries, the technology of preventing the lithium-dendrite formation, enhancing the lithium ionic conductivity, and lowering the interfacial resistance between the solid electrolyte membrane and the electrode, in order to higher the battery performance, still needs to be improved.
[Patent Literature 1] TW202014382
The performance of the current lithium batteries is limited due to the problems such as the lithium-dendrite formation, low lithium ionic conductivity and high interfacial resistance resulting from the poor contact between the solid electrolyte membrane and the electrode.
In order to solve such problems, the inventor of the present invention, after thorough research, provides a method for the fabrication of a LaZrGa(OH)x metal hydroxide precursor, the fabrication of an ion-doped all-solid-state lithium-ion conductive material with lithium ionic conductivity, and the fabrication of a free standing double layered and triple layered organic-inorganic (polymer comprising ceramics) hybrid solid electrolyte membrane using the all-solid-state lithium-ion conductive material.
That is, as a first aspect, the present invention relates to a method for the fabrication of a LaZrGa(OH)x metal hydroxide precursor, comprising the steps of:
As a second aspect, the present invention relates to a method for the fabrication of an ion-doped all-solid-state lithium-ion conductive material with lithium ionic conductivity, comprising the steps of:
As a third aspect, the present invention relates to a method for the fabrication of a free standing double layered organic-inorganic hybrid solid electrolyte membrane, comprising the steps of:
As a fourth aspect, the present invention relates to a method for fabrication of a free standing triple layered organic-inorganic hybrid solid electrolyte membrane, comprising the steps of:
A fifth aspect of the present invention relates to the method for the fabrication of a LaZrGa(OH)x metal hydroxide precursor material recited in the first aspect, wherein the lanthanum source in said step (a) is one or more materials selected from lanthanum sulfate, lanthanum oxalate, lanthanum acetate, lanthanum nitrate, lanthanum chloride, lanthanum fluoride, lanthanum hydroxide.
A sixth aspect of the present invention relates to the method for the fabrication of a LaZrGa(OH)x metal hydroxide precursor material recited in the first aspect, wherein the zirconium source in said step (a) is one or more materials selected from zirconium oxychloride, zirconium sulphate, zirconium phosphate, zirconium carbonate, zirconium acetate, zirconium oxynitrate, zirconium chloride, zirconium dioxide and zirconium hydroxide.
A seventh aspect of the present invention relates to the method for the fabrication of a LaZrGa(OH)x metal hydroxide precursor material recited in the first aspect, wherein the gallium source in said step (a) is one or more materials selected from gallium oxalate, gallium acetate, gallium carbonate, gallium hydroxide, gallium sulfate, gallium nitrate, gallium phosphate and gallium oxide.
An eighth aspect of the present invention relates to the method for the fabrication of a LaZrGa(OH)x metal hydroxide precursor material recited in the first aspect, wherein the concentration of the metal salt solution 1 in said step (a) is 1.0˜3 M, preferably 2.0 M; wherein in said step (a), the stoichiometric composition of La(NO3)3·6H2O, serving as a lanthanum source, ZrOCl2·8H2O, serving as a zirconium source, and Ga(NO3)3, serving as a gallium source, is 3:2:0.05˜0.5.
A ninth aspect of the present invention relates to the method for the fabrication of a LaZrGa(OH)x metal hydroxide precursor material recited in the first aspect, wherein in said step (b), the concentration of the ammonia water, which serves as a chelating agent, is 2.0˜8.0 M, preferably 3.6 M; said pH value in said reaction chamber of the TFR is controlled between 10˜12, preferably around 11; the rotation rate of said TFR is set within the range of 500˜1500 rpm, preferably 1300 rpm; the reaction time in said TFR is 8˜80 hours, preferably 12˜16 hours.
A tenth aspect of the present invention relates to the method for the fabrication of a LaZrGa(OH)x metal hydroxide precursor material recited in the first aspect, wherein the drying condition in said step (d) is at 50˜100° C. (preferably 80° C.) for 10˜30 hours, preferably 24 hours.
An eleventh aspect of the present invention relates to the method for the fabrication of an ion-doped all-solid-state lithium-ion conductive material recited in the second aspect, wherein the lithium source in said step (a) is one or more materials selected from lithium hydroxide, lithium nitrate, lithium acetate, lithium oxalate, lithium oxide, lithium chloride, lithium hydrogen phosphate, lithium phosphate and lithium carbonate; the molar ratio between the LaZrGa(OH)x metal hydroxide precursor and the lithium salt in said step (a) is 1:5. 5˜6. 650 (i.e. 5˜20% excessed amount of the lithium salt), preferably 1:6 (i.e. 10% excessed amount of the lithium salt); using lithium fluoride (LiF) or ammonium fluoride (NH4F) as the source of ion doping with the stoichiometric composition 0.05˜0.3 (preferably 0.2); the condition of grinding and mixing in the ball mill in said step (a) is 100˜650 rpm for 10 minutes to 2 hours, preferably 400 rpm/20 min, and the ball of the ball mill is one or more selected from zirconia (ZrO2) ball, hardened steel, yitrium stablized zirconia (YSZ), stainless steel, tungsten carbide, agate, sintered alumina and silicon nitride ball, wherein the weight ratio of the mixture to the ball in said step (a) is 1:1˜20, preferably 1:10.
A twelfth aspect of the present invention relates to the method for the fabrication of an ion-doped all-solid-state lithium-ion conductive material recited in the second aspect, wherein the condition of the calcining in said step (b) is: keeping the temperature at 150° C. for 1 hour as the first stage, 300˜400° C. (preferably 350° C.) for 3 hours as the second stage, 400˜600° C. (preferably 550° C.) for 1 hour as the third stage, 500˜800° C. (750° C.) for 4 hours as the fourth stage, and 800˜1000° C. (preferably 900° C.) for 1˜5 hours (preferably 2 hours) as the fifth stage. The heating rate of said five stages is 1˜10° C. min−1, preferably 3° C. min−1.
A thirteenth aspect of the present invention relates to the method for the fabrication of a double layered hybrid solid electrolyte membrane recited in the third aspect, wherein the lithium salt in said step (a) is one or more materials selected from lithium bis(trifluoromethanesulfonyl)imide, lithium bis(trifluoromethanesulfonyl)azanide, lithium bis(fluorosulfonyl)imide, lithium perchlorate, lithium trifluoromethanesulfonate, lithium bis(oxalate)borate and lithium tetrafluoroborate; the plasticizer in said step (a) is one or more materials selected from succinonitrile, adiponitrile, lithium azide, polyethylene glycol, poly(ethylene glycol) diacrylate and triallyl isocyanurate.
A fourteenth aspect of the present invention relates to the method for the fabrication of a triple layered hybrid solid electrolyte membrane recited in the fourth aspect, wherein in the process of material surface coating, the amount of coating in said step (a) and (b) is 0.05˜5.0 wt. %, preferably 0.5˜1.5 wt. %.
The present invention is also to provide an all-solid-state lithium battery with excellent performance, using said hybrid solid electrolyte membrane.
That is, as the fifteenth aspect, the present invention relates to an all-solid-state lithium battery, comprising: cathode, anode, and the hybrid solid electrolyte membrane recited in the third or the fourth aspect; wherein said hybrid solid electrolyte membrane is disposed between the cathode and the anode, serving as a separator and electrolyte at the same time; said anode is lithium metal foil; said cathode is made of a composite comprising active material, conductive agent and binder on a collector layer (aluminum foil or carbon coated aluminum foil).
The triple layered HSE membrane of the present invention utilizes a multiwall carbon nanotube carbon-based material coated with Li-Nafion coating material (i.e. Li-Nafion@MWCNT), and ion-doped Ga—F-LLZO all-solid-state lithium-ion conductive material coated with Li-Nafion coating material (i.e. Li-Nafion@Ga—F-LLZO), to increase the conducting path of the lithium ions and inhibit the lithium-dendrite formation.
The present invention also measures and analyzes the lithium ionic conductivity, electrochemical stability and interface resistance behavior, etc. of the prepared double and triple layered HSE membrane. The ionic conductivity of the Ga—F-LLZO all-solid-state lithium-ion conductive pellet under room temperature is 2.50×10−4 S cm−1. The ionic conductivities of the double layered and triple layered HSE membranes under room temperature are 2.67×10−4 S cm−1 and 4.45×10−4 S cm−1, respectively.
The all-solid-state lithium battery of the present invention may enhance the lithium ionic conductivity with an increased lithium ion transmission path, and lower the interfacial resistance between the solid electrolyte membrane and the electrode, therefore the battery may have excellent performance, and prevent the lithium-dendrite formation to enhance the safety.
The following examples are given to describe the method for the fabrication of the LaZrGa(OH)x metal hydroxide precursor, the all-solid-state lithium-ion conductive material, the hybrid solid electrolyte membrane, and the performance of the all-solid-state lithium battery using said hybrid solid electrolyte membrane. It should be noted that the following examples are only given for illustrative purposes and are not intended to limit the scope of the present invention.
Preparing the La3Zr2Ga0.3(OH)x Hydroxide Precursor, x=17.9:
Comparing with a Batch reactor, a stronger mixing capability may be achieved by a TFR due to the flowing theory of the Taylor flow, which may be about 7 times of the mixing capability of a Batch reactor. Therefore, the smaller particle size distribution (about ½ of which achieved by a Batch reactor), pure cubic phase of the hydroxide precursor and a higher yield (volume of the reactor: 1˜300 L) may be achieved in shorter reaction time (about ⅛ of the reaction time; increased mass transfer rate: 3.3 vs. 1.0 m s−1). As a result, the present invention prepares the La3Zr2Ga0.3(OH)17.9 metal hydroxide precursor with a TFR reactor.
One embodiment of preparing the LaZrGa(OH)x metal hydroxide precursor is as follow:
First, weigh metal salt powders to prepare the 2M metal salt solution of La(NO3)3·6H2O, ZrOCl2·8H2O and Ga(NO3)3 with the stoichiometric composition being 3:2:0.3, which may be adjusted in different preparation, and dissolve which in 1 L deionized water for 4 hours. At the same time, prepare 4M sodium hydroxide (NaOH) precipitant solution for equimolar reaction. Prepare 3.6M of ammonia water (NH4OH) as a chelating agent for co-precipitation to prepare La3Zr2Ga0.3(OH)17.9. During the co-precipitation reaction in the TFR reactor (LCTR-tera 3100, the volume of the reactor: 0.5˜1.5 L), adjust and control the pH value in the reaction chamber at 11, the rotation rate of the reactor at 1300 rpm, the feed rate at 1.7 ml min−1, and the reaction time within 12˜16 hours at 25° C. The TFR reactor, having a working volume of 1 L, comprises two coaxial cylinders. Two steel cylinders are both disposed with heating jackets to control the reaction temperature. Spin the inner cylinder and keep the outer cylinder stationary to have a Taylor vortex flow within the gap between the inner cylinder and the outer cylinder. Finally, continuously collect the suspension of the La3Zr2Ga0.3(OH)17.9 metal hydroxide precursor sample at the nozzle end of the cylinder of the reactor. Filter the sample with filter paper and wash the sample several times with ethanol and deionized water to remove the residual ions (Na+, NO3− and other ions). Dry the sample in an oven at 80° C. for 24 hours. The La3Zr2Ga0.3(OH)17.9 metal hydroxide precursor powders is therefore prepared.
Preparing the Ion-Doped Ga—F-LLZO (i.e. Li5.9Ga0.3La3Zr2F0.2O11.8) all-Solid-State Lithium-Ion Conductive Material:
The steps to prepare the ion-doped Ga—F-LLZO all-solid-state lithium-ion conductive material with fluorine doped (stoichiometry being 0.2, using LiF as the source of ion doping) are stated as follow. Place the dried La3Zr2Ga0.3(OH)17.9 metal hydroxide precursor prepared in Example 1, 10% excess of LiOH·H2O (i.e. the molar ratio between La3Zr2Ga0.3(OH)17.9 and LiOH·H2O is 1:6, in order to compensate the loss of lithium under high temperature due to the subsequent calcining), and LiF in a milling pot containing 99% methanol solvent (a zirconia ball is used, wherein the weight ratio between the mixture and the ball is 1:10), and grind and mix the mixture with a planetary ball mill (Planetary Ball Mill PM 200, Retsch, Germany) at 400 rpm for 20 minutes. After grinding, take out the milling ball from the milling pot, and place the milling pot in an oven, where the temperature is 80° C., to dry the mixture for 5-10 hours in order to remove the methanol solvent and produce the powder. Finally, calcine the dried powder in a furnace in air atmosphere. The Ga—F-LLZO all-solid-state lithium-ion conductive material is produced. The calcining condition is shown as Table 1.
Preparing the Free Standing Double Layered Hybrid Solid Electrolyte (Bi-HSE) Membrane:
One embodiment to prepare the free standing double layered hybrid solid electrolyte membrane, i.e. double layered Ga—F-LLZO@PVDF+PAN/LiTFSI/SN//Ga—F-LLZO@PVDF+PAN/LiTFSI/SN membrane, is shown as follow (in the present invention, different materials contained in the same layer of a membrane are separated with a “/”, different layers of the membranes are separated with a “//”, and the arrangement from top to bottom is shown as “the first layer//the second layer//the third layer):
The free standing double layered hybrid solid electrolyte membrane with lithium ionic conductivity is composed with polyvinylidene fluoride (PVDF) polymer, polyacrylonitrile (PAN) polymer, bis(trifluoromethanesulfonyl)imide (LiTFSI) lithium salt, succinonitrile (SN) plasticizer and ion-doped Ga—F-LLZO all-solid-state lithium-ion conductive material prepared in Example 2. Prepare the following two solutions, solution A and solution B, during the preparation of the membrane.
Step (1) solution A: Dissolve PVDF in dimethylformamide (DMF) solvent, add LiTFSI (the ratio of LiTFSI to PVDF and PAN is 1:1, wt. %), mix and stir at 65° C. for 4 hours to prepare homogeneous solution (solution A). Add PAN (PAN:PVDF=1:9, wt. %), SN (SN: PVDF and PAN=1:9, wt. %) and ion-doped Ga—F-LLZO all-solid-state lithium-ion conductive material (Ga—F-LLZO: PVDF and PAN=0.2:1, wt. %) into the homogeneous solution A, and stir the solution at 65° C. for 6 hours. Subsequently, coat the mixture solution with doctor-blade coating method on a glass substrate (i.e. the first layer, the glass side). Place the glass substrate in a vacuum oven under room temperature to dry and remove part of the DMF solvent.
Step (2) solution B: The preparation of solution B is similar to Step (1), but lower the ratio of LiTFSI to PVDF and PAN polymer to 1:2 (wt. %), and the ratio of Ga—F-LLZO to PVDF and PAN to 0.125:1 (wt. %). Coat solution B on the first layer, which is formed by the solution A dried under room temperature, to form a second layer (i.e. the air side). Subsequently, dry the layer at 60° C. for 48 hours. Put the double layered hybrid solid electrolyte membrane in a vacuum oven, and further dry it at 70° C. for 24 hours to remove the residual solvent.
The thickness of the prepared free standing double layered hybrid solid electrolyte membrane is about 150˜160 μm. The membrane is compressed under a condition of 500˜2000 psi, 25° C.˜60° C. to make the thickness of about 100˜150 μm, and cut it into circular with a diameter of 18 mm. The cut membrane is also as a separator and electrolyte in the battery assembly at the same time. Finally, store the prepared double layered hybrid solid electrolyte membrane in a glove box filled with argon gas to prevent from exposing to the outside environment with moisture and air.
Preparing the Free Standing Triple Layered Hybrid Solid Electrolyte (Tri-HSE) Membrane:
One embodiment to prepare the free standing triple layered hybrid solid electrolyte membrane, i.e. triple layered Li-Nafion@Ga—F-LLZO@PVDF+PAN/LiTFSI/SN//Li-Nafion@Ga—F-LLZO@PVDF+PAN/LiTFSI/SN//Li-Nafion@MWCNT@PVDF+PAN/LiTFSI/SN membrane, is shown as follow:
The free standing triple layered hybrid solid electrolyte membrane with lithium ionic conductivity is composed with polyvinylidene fluoride (PVDF) polymer, polyacrylonitrile (PAN) polymer, bis(trifluoromethanesulfonyl)imide (LiTFSI) lithium salt, succinonitrile (SN) plasticizer, multiwall carbon nanotube carbon-based material coated with lithium-Nafion (Li-Nafion) coating material (i.e. Li-Nafion@MWCNT, used for isolation and inhibition the lithium-dendrite formation), and ion-doped Ga—F-LLZO all-solid-state lithium-ion conductive material coated with Li-Nafion coating material (i.e. Li-Nafion@Ga—F-LLZO). The following three solutions, solution A, B and C, are prepared for the preparation of the membrane.
Step (1) solution A: Dissolve PVDF in dimethylformamide (DMF) solvent, add LiTFSI (the ratio of LiTFSI to PVDF and PAN is 1:1, wt. %), mix and stir at 65° C. for 4 hours to prepare homogeneous solution (solution A). Add PAN (PAN:PVDF=1:9, wt. %), SN (SN: PVDF and PAN=1:9, wt. %) and 1 wt. % Li-Nafion coating material @MWCNT (comparing to PVDF+LiTFSI+PAN+SN) into the homogeneous solution A, and stir the solution at 65° C. for 6 hours. Subsequently, coat the mixture solution on a glass substrate, place the glass substrate in a vacuum oven under room temperature to dry and remove part of the solvent. The first layer is therefore prepared (glass side).
Step (2) solution B: The preparation of solution B is similar to Step (1) in Example 3, but the ion-doped Ga—F-LLZO all-solid-state lithium-ion conductive material is replaced with 1 wt. % Li-Nafion coating material (comparing to Ga—F-LLZO)@Ga—F-LLZO. Subsequently, coat solution B on the first layer, which is formed by the solution A dried under room temperature (i.e. the second layer, the sandwiched layer).
Step (3) solution C: The preparation of solution C is similar to Step (2) in Example 3, but Ga—F-LLZO is replaced with 1 wt. % Li-Nafion@ Ga—F-LLZO, and the ratio of LiTFSI to PVDF and PAN is higher to 1:1 (wt. %). Coat solution C on the two layers, which are formed by the solution A and B dried under room temperature, to form a third layer (air side). Dry it at 60° C. for 48 hours. Place the triple layered hybrid solid electrolyte membrane in a vacuum oven for drying at 70° C. for 24 hours to remove the residual solvent.
The thickness of the prepared free standing triple layered hybrid solid electrolyte membrane is about 210˜220 μm. The membrane is compressed under a condition of 500˜2000 psi, 25° C.˜60° C. to make the thickness of about 150˜200 μm, and cut it into circular with a diameter of 18 mm. The cut membrane is also as an isolator and electrolyte in the battery assembly at the same time. Finally, store the prepared triple layered hybrid solid electrolyte membrane in a glove box filled with argon gas to prevent from exposing to the outside environment with moisture and air.
Preparing the Button-Type all-Solid-State Lithium Battery:
The cathode separately uses LiNi0.5Co0.2Mn0.3O2(named as NCM523), LiNi0.6Co0.2Mn0.2O2(NCM622), LiNi0.8Co0.1Mn0.1O2(NCM811), or LiFePO4 (LFP) as active material, which is dispersed and mixed together with Super P conductive carbon black (conductive agent) and PVDF (binder) in N-Methyl-2-Pyrrolidone (NMP) solvent to prepare the slurry of the cathode. After the stirring and mixing of the slurry, coat the mixed slurry on the aluminum foil or carbon coated aluminum foil (collector layer). Place the coated material in an oven to dry at 60° C. for 12 hours to remove the NMP solvent, and dry at 120° C. for 1 hour in an oven to remove the water or moisture. Cut the dried electrode into circular with a diameter of 1.3 cm and the surface area about 1.33 cm2.
Assemble the dried cathode (working electrode) to get CR2032 button-typed battery in a glove box filled with argon gas (1TS100-1, German MBRAUN UniLab-B, H2O and O2<0.5 ppm). Use the lithium metal foil as the anode (corresponding electrode and reference electrode) of the battery. The hybrid solid electrolyte membrane prepared in Example 3 or 4 is used as a separator and electrolyte at the same time. Besides, in the present invention, the assembled battery is defined as “cathode/electrolyte membrane/anode”. For example, when using NCM523 as a cathode, lithium metal foil as an anode, Bi-HSE membrane in Example 3 as the electrolyte membrane, the assembled battery is defined as “NCM523/Bi-HSE/Hi battery”.
Preparing the Ga—F-LLZO Pellet:
After drying at 80° C. in an oven, weighing 0.45 g Ga—F-LLZO powders and sieve with a mesh (Mesh #325). Compress the powders into the Ga—F-LLZO pellet with a diameter of 13 mm, thickness of about 1.0˜1.2 mm under 4000 psi with a tablet machine.
Analysis on Characteristics of the Materials:
Analyze the crystal structure and impurity phase of the prepared materials including metal hydroxide precursor powders, Ga—F-LLZO powders and hybrid solid electrolyte membrane with the X-ray Diffractometer (XRD, Bruker D2 PHASER, Germany, CuKα5, λ=0.1534753 nm, 30 kV, 10 mA). Analyze the surface morphology and elemental composition of the metal hydroxide precursor powders, Ga—F-LLZO powders and hybrid solid electrolyte membrane with the field emission scanning electron microscope (FE-SEM, JEOL JSM-7610F Plus, Japan) and energy-dispersive X-ray spectroscopy (EDS, Oxford X-MaxN, UK), respectively. Analyze the samples with the micro Raman spectroscopy (Micro-Raman, InVia confocal micro Renishaw, UK). Measure the particle size and distribution of the synthesized powders with the laser diffraction particle size analyzer (LS 13320, Beckman, Coulter).
Electrochemical Characterization:
Conduct a charge-discharge cycle test on the assembled battery prepared in Example 5 under a constant current, based on the current rate to be tested, within the cutoff voltage range under room temperature (25° C.). Besides, measure the ionic conductivity of the Ga—F-LLZO pellet, the double layered and the triple layered hybrid solid electrolyte membrane, with the thickness of 1.1 mm, 150 μm and 200 μm, respectively, with the electrochemical impedance spectroscope (Electrochemical impedance spectroscope, EIS; Metrohm Autolab B. V., Netherlands). The frequency range of the impedance measurement of the electrochemical impedance spectroscope is 106˜10−2 Hz, and the voltage amplitude is 10 mV.
Characterization of the La3Zr2Ga0.3(OH)17.9 Metal Hydroxide Precursor:
As shown in
Analyze the particle size distribution of the La3Zr2Ga0.3(OH)17.9 metal hydroxide precursor with the laser diffraction particle size analyzer. The powders are vibrated with an ultrasonicator (Ultrasonicator, DC-900H, Delta Co., Taiwan) for about 30 min to disperse in the ethanol solvent before the particle size distribution measurement. As shown in
As shown in
The phase information of the LLZO material with conductive lithium ion with a garnet structure may be obtained from the micro-Raman spectroscopy analysis. As shown in
Characterization of the Ion-Doped Ga—F-LLZO all-Solid-State Lithium-Ion Conductive Material:
Surface Morphology and Microstructure:
The SEM images of the dried La3Zr2Ga0.3(OH)17.9 metal hydroxide precursor powders and the Ga—F-LLZO powders are shown in
Lithium Ionic Conductivity:
After dried under 80° C., weigh 0.45 g Ga—F-LLZO powders and sieve with a mesh (Mesh #325), and compress the powders into a pellet with a diameter of 13 mm and thickness of 1.1 mm under 4000 psi. Measure the ionic conductivity of the Ga—F-LLZO pellet with an electrochemical impedance spectroscopy (EIS), as shown in
Double Layered and Tripled Layered Electrolyte Membrane:
Lithium Ionic Conductivity:
As shown in
Electrochemical Stability:
Since an electrochemical window is related to the energy density and working voltage of a battery, wider electrochemical window plays an important role in the electrochemical reaction of a lithium battery. Measure the electrochemical stability of the double layered hybrid solid electrolyte (Bi-HSE) membrane and triple layered hybrid solid electrolyte (Tri-HSE) membrane by linear sweep voltammetry (LSV). As shown in
Surface Morphology and Microstructure:
Electrochemical performance of the all-solid-state lithium battery (double layered hybrid solid electrolyte membrane):
Conduct the electrical tests on the all-solid-state lithium battery using the HSE membrane in Example 3 to confirm the properties of the hybrid electrolyte membrane in the all-solid-state battery.
NCM523/Bi-HSE/Li Battery:
Use the double layered HSE membrane, the NCM523 with 65% active materials as the cathode, and the lithium metal foil as the anode, to conduct a charge-discharge cycle test under room temperature, with the rate of 0.2C and the cutoff voltage of 2.5˜4.2V for 30 cycles.
NCM811/Bi-HSE/Li Battery:
Use the double layered HSE membrane, the NCM811 with 65% active materials as the cathode, and the lithium metal foil as the anode, to conduct a charge-discharge cycle test under room temperature, with the rate of 0.5C and the cutoff voltage of 2.5˜4.0V for 30 cycles.
Electrochemical Performance of the all-Solid-State Lithium Battery (Triple Layered Hybrid Solid Electrolyte Membrane):
Conduct the electrical tests on the all-solid-state lithium battery using the HSE membrane in Example 4 to confirm the properties of the hybrid electrolyte membrane in the all-solid-state battery.
NCM811/Tri-HSE/Li Battery:
Use the triple layered HSE membrane, the NCM811 with 65% active materials as the cathode, and the lithium metal foil as the anode, to conduct a charge-discharge cycle test under room temperature, with the rate of 0.5C and the cutoff voltage of 2.5˜4.2V for 30 cycles. The result is shown in
NCM622/Tri-HSE/Li Battery:
Use the triple layered HSE membrane, the NCM622 with 70% active materials as the cathode, and the lithium metal foil as the anode, to conduct a charge-discharge cycle test under room temperature, with the rate of 0.5C and the cutoff voltage of 2.6˜4.2V for 30 cycles. The result is shown in
LFP/Tri-HSE/Li Battery:
Use the triple layered HSE membrane, the LiFePO4 with 80% active materials as the cathode, and the lithium metal foil as the anode, to conduct a charge-discharge cycle test under room temperature, with the rate of 0.2C and the cutoff voltage of 2.0˜4.0V for 3 cycles. The result is shown in
To summarize, the all-solid-state lithium battery of the present invention may enhance the lithium ionic conductivity with an increased lithium ion transmission path, and lower the interfacial resistance between the solid electrolyte membrane and the electrode, therefore the battery may have excellent performance, and prevent the lithium-dendrite formation to enhance the safety.
Number | Date | Country | |
---|---|---|---|
Parent | 17383799 | Jul 2021 | US |
Child | 18231883 | US |