Electrode materials that include an active composition of the formula MgzMxOy for group II cation-based batteries

Patent metadata

Field	Value
Publication number	US-11532806-B2
Application number	US-202017006682-A
Country	US
Kind code	B2
Filing date	Aug 28, 2020
Priority date	Apr 1, 2014
Publication date	Dec 20, 2022
Grant date	Dec 20, 2022

Abstract

Preparation, characterization, and an electrochemical study of Mg0.1V2O5 prepared by a novel sol-gel method with no high-temperature post-processing are disclosed. Cyclic voltammetry showed the material to be quasi-reversible, with improved kinetics in an acetonitrile-, relative to a carbonate-, based electrolyte. Galvanostatic test data under a C/10 discharge showed a delivered capacity >250 mAh/g over several cycles. Based on these results, a magnesium anode battery, as disclosed, would yield an average operating voltage ˜3.2 Volts with an energy density ˜800 mWh/g for the cathode material, making the newly synthesized material a viable cathode material for secondary magnesium batteries.

First claim

We claim:

1. A composition of matter comprising a compound according to the formula: Mg z ,M x O y ,
wherein M is vanadium (V) metal, a mole fraction of Mg in the compound is z/(x+y+z), a mole fraction of metal M in the compound is x(x+y+z) and a mole fraction of O in the compound is y/(x+y+z),
wherein x=2, y=5 and z=0.1, and
wherein the composition of further comprises: an internal water content of 1.8 equivalents of H 2 O per formula unit at room temperature, resulting in a compound formula of Mg 0.1 V 2 O 5 *1.8H 2 O.

2. The composition of claim 1 , wherein:
the compound exhibits a crystallographic structure that forms ion channels through which magnesium ions in the +2 valence state (Mg 2+ ) flow.

3. The composition of claim 2 , wherein:
a rate of Mg 2+ ion flow is affected by the crystallographic structure.

4. The composition of claim 2 , wherein:
a rate of Mg 2+ ion flow is affected by a bonding character within the ion channels.

5. The composition of claim 4 , wherein:
the bonding character within the ion channels is a function of a water content within the compound.

6. The composition of 2 , wherein:
the compound comprises a plurality of crystallites, each crystallite having a characteristic size.

7. The composition of claim 6 , wherein the characteristic size of the crystallites is less than one micrometer (1 μm).

8. The composition of claim 6 , wherein:
a rate of Mg 2+ ion flow is affected by the characteristic size of the plurality of crystallites.

9. The composition of claim 8 , wherein:
the rate of Mg 2+ ion flow increases with a decrease in the characteristic size of the plurality of crystallites.

10. An electrode material comprising:
an active material, the active material comprising a composition of the formula Mg z M x O y , and an internal water content of 1.8 equivalents of H 2 O per formula unit at room temperature, resulting in a compound formula of Mg 0.1 V 2 O 5 *1.8H 2 O;
wherein M is vanadium (V) metal,
z/(x+y+z) is the mole fraction of Mg,
x/(x+y+z) is the mole fraction of metal M, and
y/(x+y+z) is the mole fraction of O in the active material; and
wherein x is equal to 2, y is equal to 5 and z is equal to 0.1.

11. The electrode material of claim 10 , wherein:
the active material is incorporated into a cathode; and
a response of the cathode to an applied voltage is reversible when the cathode is immersed in an electrolyte containing Mg 2+ ions.

12. A battery system comprising:
a battery comprising a cathode, an anode, and an electrolyte;
wherein the cathode comprises an active material having the formula Mg g M x O y , and an internal water content of 1.8 equivalents of H 2 O per formula unit at room temperature, resulting in a compound formula of Mg 0.1 V 2 O 5 *1.8H 2 O;
wherein M is vanadium (V) metal,
z/(x+y+z) is the mole fraction of Mg,
x/(x+y+z) is the mole fraction of the metal V, and
y/(x+y+z) is the mole fraction of O in the compound;
wherein x is equal to 2, y is equal to 5 and z is equal to 0.1;
wherein the anode comprises a Mg-containing material; and
wherein the electrolyte comprises an ionic solution containing Mg 2+ ions, Li 1+ ions, or both.

13. The battery system of claim 12 , wherein:
the battery is a secondary battery.

14. The battery system of claim 13 , wherein:
the cathode exhibits electrochemically relevant reversibility when immersed in the electrolyte and subjected to a voltage differential with respect to the anode.

Assignees

• Univ New York State Res Found

Inventors

• Takeuchi Kenneth
• Takeuchi Esther
• Marschilok Amy

Classifications

• H01M4/5825

  Oxygenated metallic salts or polyanionic structures, e.g. borates, phosphates, silicates, olivines · CPC title

• C01P2004/03

  obtained by SEM · CPC title

• C01G31/00 Primary

  Compounds of vanadium · CPC title

• H01M10/054

  Accumulators with insertion or intercalation of metals other than lithium, e.g. with magnesium or aluminium · CPC title

• H01M4/52

  of nickel, cobalt or iron · CPC title