Composition for manufacture of electrodes and electrodes and batteries resulting therefrom
Composition for the manufacture of composite electrodes usable in electrochemical devices and comprising at least: (i) one lithium insertion material; (ii) one electronic conducting material; (iii) one amino-functional cationic polyelectrolyte; (iv) water.
1. A combination comprising an aqueous suspension A and a composition B, wherein the aqueous suspension A comprises:
one of the two materials selected from:
(i) lithium insertion materials,
(ii) an electronic conductor, and
(iii) at least one amino-functional cationic polyelectrolyte selected from polymers produced by the combination of monomers carrying functions selected from the group consisting of: aminal, oxime, nitrile, imine, primary amine, secondary amine, tertiary amine, pyridine, enamine, ynamine, hydrazone, amide, amino acid, amino ester, isocyanate, nitrene, carbamate, carbazate, hydrazine, oxasiridine, β-lactam, enamide, cyanhydrin, pyrimidine, hydropyrimidine, pyrazine, piperazine, imidazolidine, pyridazine, aziridine, azetidine, pyrrolidine, piperidine, oxazole, oxazoline, oxazolidine, oxazolidinone, imidazoles, pyrrole, carbamic acid, urea, imide, hydroxymic acid, triazole, and isooxazole, alone or in combination with nonionic monomers,
the quantity of polyelectrolyte being between 1.10 −5 and 5% by weight of the quantity of material (i) or (ii) also present in A and
in that the composition B, which may be in the form of a powder or in the form of an aqueous suspension, comprises the other material selected from (i) and (ii).
2. The combination as claimed in claim 1 , wherein the lithium insertion material is selected from the group consisting of:
transition metal oxides having a spinel structure of the LiM 2 O 4 type where M is a metal atom containing at least one of the metal atoms selected from the group consisting of Mn, Fe, Co, Ni, Cu, Mg, Zn, V, Ca, Sr, Ba, Ti, Al, Si, B and Mo;
transition metal oxides having a lamellar structure of the LiMO 2 type where M is a metal atom containing at least one of the metal atoms selected from the group consisting of Mn, Fe, Co, Ni, Cu, Mg, Zn, V, Ca, Sr, Ba, Ti, Al, Si, B and Mo;
oxides having a polyanionic frame of the LiM y (XO z ) n type where M is a metal atom containing at least one of the metal atoms selected from the group consisting of Mn, Fe, Co, Ni, Cu, Mg, Zn, V, Ca, Sr, Ba, Ti, Al, Si, B and Mo, and X is an atom selected from the group consisting of P, Si, Ge, S and As, and y, z and n are positive integers; and
vanadium-based oxides.
3. The combination as claimed in claim 2 , wherein the lithium insertion material is selected from the group consisting of:
transition metal oxides having a spinel structure of the LiM 2 O 4 type where M is a metal atom containing at least one of the metal atoms selected from the group consisting of Mn and Ni;
transition metal oxides having a lamellar structure of the LiMO 2 type where M is a metal atom containing at least one of the metal atoms selected from the group consisting of Mn, Co and Ni; and
oxides having a polyanionic frame with an olivine structure such as LiFePO 4 .
4. The combination as claimed in claim 1 , wherein the lithium insertion material is selected from the group consisting of: a lithium alloy, a nanodispersion of a lithium alloy in a lithium oxide, carbon, graphite, a lithium titanium spinel Li 1+y Ti 2x−x/4 O 4 (0≦x≦1, 0≦y≦1), lithium and transition metal; nitride a titanium oxide, and mixtures thereof.
5. The combination as claimed in claim 1 , wherein the electronic conductor is a material having a conductivity higher than 1 S.cm −1 at 25° C.
6. The combination as claimed in claim 1 , wherein the electronic conductor has a grain size distribution lower than that of the insertion material.
7. The combination as claimed in claim 1 , wherein the electronic conductor is a material having a specific surface area higher than 10 m 2 .g −1 .
8. The combination as claimed in claim 1 , wherein the electronic conductor is selected from the group formed by carbon black, active carbon and mixtures thereof.
9. The combination as claimed in claim 1 , wherein the amino-functional cationic polyelectrolyte is a synthetic polyelectrolyte.
10. The combination as claimed in claim 1 , wherein the amino-functional cationic polyelectrolyte is selected from the group consisting of: poly(allylamine hydrochloride) (PAH), poly(diallyldimethylammonium chloride) (PDDA), poly(vinylpyridine) (PVPy), polyaniline (PANi), polyethylenimine (PEI) and poly(N,N,N-trimethylammonium ethyl acrylate chloride) and mixtures thereof.
11. The combination as claimed in claim 1 , wherein the quantity of polyelectrolyte is between 1.10 −3 and 1% by weight of the quantity of material selected from the insertion material (i) and the electronic conductor (ii) also present in A.
12. The combination as claimed in claim 1 , wherein the electronic conductor (ii) accounts for between 1 and 10% by weight of the total weight of the components (i)+(ii)+(iii).
13. The combination as claimed in claim 1 , wherein the quantity of insertion material (ii) is between 70 and 99% by weight of the total weight of the components (i)+(ii)+(iii).
14. The combination as claimed in claim 1 , wherein the composition B further comprises one or more components selected from the group consisting of:
a dispersant, and
a synthetic anionic polyelectrolyte.
15. The combination as claimed in claim 14 , wherein the anionic polyelectrolyte has sulfonic acid and sulfate ester groups.
16. The combination as claimed in claim 14 , wherein the dispersant is a nonionic surfactant.
17. The combination as claimed in claim 14 , wherein the quantity of dispersant is between 1.10 ˜ 5 and 25% by weight of the quantity of material selected from the insertion material (i) and the electronic conductor (ii) also present in B.
18. The combination as claimed in claim 14 , wherein the quantity of anionic polyelectrolyte is between 1.10 −5 and 5% by weight of the quantity of material selected from the insertion material (i) and the electronic conductor (ii) also present in B.
19. A composition resulting from the mixture of compositions A and B of the combination as claimed in claim 1 , wherein the composition comprises:
a lithium insertion material;
(ii) an electronic conductor;
(iii) an amino-functional cationic polyelectrolyte; and
(iv) water.
20. The composition as claimed in claim 19 , further comprising at least one compound selected from the group consisting of a thickener and a binder, in a quantity of between 0 and 10% by weight of the total weight of compounds (i)+(ii)+(iii).
21. The composition as claimed in claim 19 , wherein a dry extract of the composition is between 25 and 70%.
22. A method for preparing a composition as claimed in claim 19 , comprising:
(a) preparing a composition A in at least two steps:
dissolving the amino-functional cationic polyelectrolyte (iii) in water, then
introducing the first material selected from the group consisting of: (i) an insertion material and (ii) an electronic conductor,
(b) preparing a composition B, and
(c) mixing the compositions A and B.
23. The method as claimed in claim 22 , wherein the composition B comprises a solvent and a compound selected from the group consisting of a dispersant and an anionic polyelectrolyte, and wherein step (b) comprises at least the following steps:
dissolving, the dispersant and/or the anionic polyelectrolyte in the solvent, then
introducing the second material selected from the group consisting of (i) an insertion material and (ii) an electronic conductor.
24. A method for fabricating a composite electrode, said method comprising:
preparing a composition following the method as claimed in claim 22 , and
applying the composition to a current collector.
25. The method as claimed in claim 24 , wherein the composition is applied to the current collector by coating or by screen printing.