PROCESS FOR FLUORINATION OF AN LLZO GARNET

1 . A fluorination process comprising bringing an atmosphere comprising difluorine gas into contact with an inorganic compound M having a garnet-type structure, which is based on the elements Li, La, Zr, A and O and for which the relative composition of the Li, La, Zr and A cations corresponds to the formula (I):

Li x La 3 Zr z A w   (I)

wherein:

A denotes at least one element selected from the group consisting of Al, Ga, Nb, Fe, W and Ta;

x, z and w denote real numbers;

1.20<z≤2.10;

0<w≤0.80;

4.00≤x≤10.50;

the duration of the contact between the solid and the fluorinated atmosphere is between 2 minutes and 4 hours; and

the temperature at which the fluorination is carried out is between 20° C. and 300° C.

2 . The process as claimed in claim 1 , wherein the inorganic compound M comprises the oxide of formula (II):

Li x1 La 3 Zr z A w O 12   (II)

wherein z and w are as defined in claim 1 and x1 is a positive real number which is such that the electroneutrality of the oxide is ensured.

3 . A fluorination process comprising bringing an atmosphere containing difluorine gas into contact with the oxide of formula (II):

[Li x1 La 3 Zr z A w O 12 ]  (II)

wherein:

A denotes at least one element selected from the group consisting of Al, Ga, Nb, Fe, W and Ta;

x1, z and w denote real numbers;

1.20<z≤2.10;

0<w≤0.80; and

x1 is a positive real number which is such that the electroneutrality of the oxide is ensured.

4 . The process as claimed in claim 1 , wherein the element zirconium is partially replaced by the element hafnium.

5 . (canceled)

6 . (canceled)

7 . (canceled)

8 . (canceled)

9 . (canceled)

10 . (canceled)

11 . (canceled)

12 . A garnet-type inorganic compound based on the elements Li, La, Zr, A, O and optionally Hf which is obtained by the process as described in claim 1 .

13 . An inorganic compound having a garnet-type structure based on the elements O, Li, Zr, A, the relative proportions of which are those of the formula (I):

Li x La 3 Zr z A w   (I)

wherein:

A denotes at least one element selected from the group consisting of Al, Ga, Nb, Fe, W and Ta;

x, z and w denote real numbers;

1.20<z≤2.10;

0<w≤0.80; and

4.00≤x≤10.50;

this compound also comprising the element F and having at least one of the following characteristics:

a signal located between −125.0 and −129.0 ppm on a ( 19 F) solid-state NMR spectrum, the reference at δ=0 ppm being that of the compound CF 3 COOH; and

a ratio R less than or equal to 50%, R being the ratio between the intensity of the vibrational band of the C—O bond of the carbonate groups (symmetric stretching v) located around 1090 cm −1 to the intensity of the stretching band of the bonds in the ZrO 6 octahedra located around 648 cm −1 , these two intensities being determined by Raman spectroscopy.

14 . The inorganic compound as claimed in claim 13 , wherein the element zirconium is partially replaced by the element hafnium.

15 . (canceled)

16 . The inorganic compound as claimed in claim 12 , the crystalline structure of which consists of a skeleton of LaO 8 dodecahedra (La of coordination number 8) and of ZrO 6 octahedra (Zr of coordination number 6).

17 . The inorganic compound as claimed in claim 12 , the crystalline structure of which consists of a skeleton of LaO 8 dodecahedra of coordination number 8 (24c site) and of ZrO 6 octahedra of coordination number 6 (16a site).

18 . The inorganic compound as claimed in claim 12 , wherein some Li atoms, are present at the 24d tetrahedral sites or 48g and 96h octahedral sites.

19 . The inorganic compound as claimed in claim 12 , comprising La—F and/or Zr—F bonds.

20 . The inorganic compound as claimed in claim 12 , having, by ( 19 F) solid-state NMR spectroscopy, the reference at δ=0 ppm being that of the compound CF 3 COOH, a signal between −98.0 and −102.0 ppm and/or a signal between −58.0 and −62.0 ppm.

21 . The inorganic compound as claimed in claim 12 , of which the proportion of fluorine in the compound expressed by weight of the element fluorine relative to the total weight, is less than or equal to 10.0%, and is greater than or equal to 0.01%.

22 . (canceled)

23 . The inorganic compound as claimed in claim 12 , having a cubic crystal structure.

24 . The organic compound as claimed in claim 23 , to which the crystal structure belongs to the Ia 3d space group or to the I-43d space group.

25 . The inorganic compound as claimed in claim 12 , having a ratio R less than or equal to 50%, R being the ratio between the intensity of the vibrational band of the C—O bond of the carbonate groups (symmetric stretching v) located around 1090 cm −1 to the intensity of the stretching band of the bonds in the ZrO 6 octahedra located around 648 cm −1 , these two intensities being determined by Raman spectroscopy and R being determined after storing the inorganic compound in an air-filled sealed flask for a period of at least two months, in particular of two months.

26 . The inorganic compound as claimed in claim 12 , characterized in that the intensity of the vibrational mode ν 3 and/or of the vibrational mode ν 2 of the carbonate groups, these modes being respectively located between 1350 and 1600 cm −1 and between 890 and 1350 cm −1 , is less than or equal to 50%, this intensity being determined by infrared spectroscopy in total attenuated reflectance mode.

27 . An electrode E comprising:

a metal support;

a layer of a composition (C) in contact with the metal substrate, said composition (C) comprising:

(i) the inorganic compound as claimed in claim 12 ;

(ii) at least one electroactive compound (EAC);

(iii) optionally at least one material which conducts the Li ions other than the fluorinated oxide (LiCM);

(iv) optionally at least one electrically-conductive material (ECM);

(v) optionally a lithium salt (LIS); and

(vi) optionally at least one polymer binder material (P).

28 . A solid electrolyte of a lithium ion battery comprising the inorganic compound as described in claim 12 .

29 . A method of preparing a lithium battery, the method comprising: preparing an electrode comprising the inorganic compound as described in claim 12 .