3D magnesium battery and method of making the same
3-D magnesium voltaic cells have a magnesium anode coated on multiple opposing surfaces with a continuous protective/electrolyte layer that is ionically conductive and electronically insulating. The resulting protected 3-D magnesium anode is coated on multiple opposing surfaces with a continuous cathode layer that is electronically and ionically conductive, and includes a magnesium storage medium. Suitable magnesium anodes, in particular, magnesium foam anodes, can be made by pulsed galvanostatic deposition of magnesium on a copper substrate. The protective layer can be formed by electropolymerization of a suitable methylacrylate ester. The continuous cathode layer can be a slurry cathode having powders of an electronic conductor and a reversible magnesium storage component suspended in a magnesium electrolyte solution.
1. A three dimensional (3-D) magnesium voltaic cell, comprising:
a magnesium foam anode;
a continuous protective layer contacting the magnesium foam anode on substantially all surfaces; the continuous protective layer being electrically insulative and ionically conductive; and
a continuous slurry cathode layer contacting substantially all surfaces of the continuous protective layer, the continuous slurry cathode layer comprising:
a reversible magnesium storage component;
an electronic conductor; and
a magnesium ion conductor.
2. The 3-D magnesium voltaic cell as recited in claim 1 , wherein the continuous protective layer comprises a polymer or co-polymer of at least one methacrylic acid ester.
3. The 3-D magnesium voltaic cell as recited in claim 2 , wherein the at least one methacrylic acid ester is selected from the group consisting of poly(glycidyl methacrylate) and poly(3-sulfopropyl methacrylate).
4. The 3-D magnesium voltaic cell as recited in claim 1 , wherein the magnesium foam anode is formed entirely of magnesium metal.
5. The 3-D magnesium voltaic cell as recited in claim 1 , wherein the magnesium foam anode comprises a magnesium insertion anode.
6. The 3-D magnesium voltaic cell as recited in claim 1 , wherein the magnesium foam anode comprises a copper foam substrate having a surface layer of magnesium when at least partially charged.
7. The 3-D magnesium voltaic cell as recited in claim 1 , wherein the reversible magnesium storage component comprises a conjugated quinone.
8. The 3-D magnesium voltaic cell as recited in claim 1 , wherein the magnesium ion conductor comprises an anion having a formula:
[B y H( y-z-i )R z X i ]2-,
[CB( y-1 )H( y-z-i )R z X i ]—,
[C 2 B( y-2 )H( y-t-j-1 )R t X j ]—,
[C 2 B( y-3 )H( y-t-j )R t X j ]—, or
[C 2 B( y-3 )H( y-t-j-1 )R t X j ]2-,
wherein y is an integer within a range of 6 to 12; (z+i) is an integer within a range of 0 to y; (t+j) is an integer within a range of 0 to (y−1); and X is F, Cl, Br, I, or a combination thereof; and wherein R is alkyl, aryl, alkoxy, aryloxy, a fluorinated derivative of the aforementioned, or a moiety having any combination of the aforementioned.
9. The 3-D magnesium voltaic cell as recited in claim 1 , wherein the magnesium ion conductor comprises Mg(CB 11 H 12 ) 2 .
10. The 3-D magnesium voltaic cell as recited in claim 1 , wherein the continuous cathode slurry layer comprises 20 percent, by volume, 5,7,12,14-pentacenetetrone as reversible magnesium storage component, 0.8%, by volume, Ketjen black as electronic conductor, and 79.2%, by volume, 0.3 M Mg(CB 11 H 12 ) 2 in tetraglyme.