Rechargeable battery using an aqueous binder
A battery having an electrode mix comprising water, a conductive additive and poly (acrylonitrile-co-acrylamide) co-polymer as a binder. The use of poly (acrylonitrile-co-acrylamide) co-polymer eliminates the need for a separate thickener.
1. A battery comprising:
a positive electrode mix comprising:
a positive active material comprising a lithium transition metal oxide;
a water soluble binder comprising a poly (acrylonitrile-co-acrylamide) polymer and water; and
a conductive additive selected from the group consisting of carbon black, acetylene black, carbon fibers, coke, high surface area carbon and graphite and combination thereof;
a negative electrode mix comprising:
a negative active material selected from the group consisting of graphite, hard carbon, silicon, tin and lithium titanate;
an organic solvent-stable, water soluble binder in the absence of a thickening agent and a wetting agent, the binder comprising a poly (acrylonitrile-co-acrylamide) polymer and water; and
the conductive additive; and
an electrolyte comprised of lithium salt in cyclic and linear carbonates.
2. The battery according to claim 1 , wherein a mole ratio of acrylonitrile units to acrylamide units is between about 3:1 and 1:1.
3. The battery according to claim 2 , wherein the mole ratio of acrylonitrile units to acrylamide units is about 2:1.
4. The battery according to claim 1 , wherein an average molecular weight of the polymer is between about 10,000 and 200,000.
5. The battery according to claim 4 , wherein the average molecular weight of the polymer is between about 100,000 and 200,000.
6. The battery according to claim 1 , wherein the lithium transition metal oxide is selected from the group consisting of LiCoO 2 , LiNiO 2 , LiNi 1/3 Co 1/3 Mn 1/3 O 2 , LiNi 0.8 Co 0.15 Al 0.05 O 2 , Li 1+x Ni 1/3 Co 1/3 Mn 1/3 O 2 , LiMn 2 O 4 LiFePO 4 coated with one of graphite and carbon and Li 2 Mn 2 O 4 , LiMPO4 where M is one or more of the first row transition-metal cations selected from the group consisting of Fe, Mn, Ni, Ti, Co and combinations thereof.
7. A battery comprising:
a positive electrode mix comprising:
a positive electrode active material;
a water soluble binder comprising a poly (acrylonitrile-co-acrylamide) polymer and water; and
a conductive additive;
a negative electrode mix comprising:
a negative electrode active material;
a water soluble binder comprising a poly (acrylonitrile-co-acrylamide) polymer and water; and
a conductive additive; and
an electrolyte, and wherein the water soluble binder is provided in the absence of a thickening agent and a wetting agent.
8. The battery according to claim 7 , wherein the positive electrode active material comprises between about 80 to 95 percent by weight of the positive electrode mix.
9. The battery according to claim 8 , wherein the conductive additive material comprises between about 1 to 10 percent by weight of the positive electrode mix.
10. The battery according to claim 9 , wherein the water soluble binder comprises between about 1 to 10 percent by weight of the positive electrode mix.
11. The battery according to claim 7 , wherein the negative electrode active material comprises between about 80 to 95 percent by weight of the negative electrode mix.
12. The battery according to claim 11 , wherein the conductive additive material comprises between about 0 to 10 percent by weight of the negative electrode mix.
13. The battery according to claim 12 , wherein the water soluble binder comprises between about 1 to 10 percent by weight of the negative electrode mix.