High rate, long cycle life battery electrode materials with an open framework structure
A battery includes a cathode, an anode, and an aqueous electrolyte disposed between the cathode and the anode and including a cation A. At least one of the cathode and the anode includes an electrode material having an open framework crystal structure into which the cation A is reversibly inserted during operation of the battery. The battery has a reference specific capacity when cycled at a reference rate, and at least 75% of the reference specific capacity is retained when the battery is cycled at 10 times the reference rate.
1. A battery comprising:
a cathode;
an anode; and
an aqueous electrolyte disposed between the cathode and the anode and including a cation A different from Li + ,
wherein at least one of the cathode and the anode includes an electrode material having a Prussian Blue crystal structure into which the cation A is reversibly inserted during operation of the battery, and
wherein the aqueous electrolyte has a pH that is less than 3.
2. The battery of claim 1 , wherein the battery has a reference specific capacity when cycled at a reference rate of 1 C, and at least 75% of the reference specific capacity is retained when the battery is cycled at 10 times the reference rate.
3. The battery of claim 2 , wherein at least 60% of the reference specific capacity is retained when the battery is cycled at 100 times the reference rate.
4. The battery of claim 2 , wherein the battery has a reference, round-trip energy efficiency when cycled at the reference rate, and at least 85% of the reference, round-trip energy efficiency is retained when the battery is cycled at 10 times the reference rate.
5. The battery of claim 1 , wherein the cation A is at least one of Na + and Ba 2+ .
6. The battery of claim 1 , wherein the cation A is at least one of K + , Rb + , Cs + , and NH 4 + .
7. The battery of claim 1 , wherein the cation A has a Stokes ionic diameter greater than 3.5 Å.
8. The battery of claim 1 , wherein the electrode material is represented as:
A x P y [R(CN) 6-w L w ] z
wherein
A is at least one alkali or alkaline earth metal cation,
P is at least one metal cation,
R is at least one metal cation,
L is an anion,
x, y, and z are related based on electrical neutrality,
x>0,
y>0,
z>0, and
0≦w≦6.
9. The battery of claim 8 , wherein P is a cation of copper.
10. The battery of claim 8 , wherein P includes cations of at least two different row 4 transition metals, and at least one of the transition metals is copper.
11. The battery of claim 8 , wherein R is selected from cations of Fe, Mn, Cr, and Co.
12. The battery of claim 1 , wherein at least one of the cathode and the anode includes a coating including the electrode material, and a thickness of the coating is at least 500 nm.
13. The battery of claim 12 , wherein the thickness of the coating is at least 1 μm.
14. The battery of claim 1 , wherein a mass loading of the electrode material within at least one of the cathode and the anode is at least 500 μg/cm 2 .
15. The battery of claim 14 , wherein the mass loading is at least 1 mg/cm 2 .
16. The battery of claim 1 , wherein the electrode material includes particles having a grain size no greater than 1 μm.
17. The battery of claim 16 , wherein the grain size is no greater than 200 nm.
18. The battery of claim 1 , wherein the pH is less than 2.
19. The battery of claim 1 , wherein the aqueous electrolyte includes water as a primary solvent and at least one co-solvent having a reduced polarity relative to water.
20. The battery of claim 1 , wherein the cathode includes the electrode material as a cathode material, and the anode includes an anode material into which the cation A is reversibly inserted during operation of the battery.
21. The battery of claim 1 , wherein the cathode includes the electrode material, and the anode includes an electrochemical double-layer capacitor material.
22. The battery of claim 21 , wherein the electrochemical double-layer capacitor material is activated carbon.