Prussian blue positive electrode material, preparation method therefor, and electrochemical energy storage device
The present disclosure provides a prussian blue analogue positive electrode material, a preparation method therefor and an electrochemical energy storage device. A molecular formula of the prussian blue analogue positive electrode material is A x M c [M′(CN) 6 ] 1-y (b-H 2 O) 6y-d L d .□ y .(i-H 2 O) z , where, A is one or more selected from a group consisting of alkali metal cation, alkaline-earth metal cation, Zn 2+ and Al 3+ ; M is a metal with the valence of 2+ or 3+; M′ is a metal with the valence of 2+ or 3+; b-H 2 O is a coordinated water; □ is a M′(CN) 6 cavity; L is a neutral ligand, the neutral ligand is one or more selected from a group consisting of CH 3 CN, NH 3 , CO and C 5 H 5 N; i-H 2 O is an interstitial water; 0<x≤2; 0<c≤1; 0<y<1; 0<d≤6y; 0≤z≤16. In the prussian blue analogue positive electrode material of the present disclosure, the neutral ligand L participates in the coordination with a transition metal and substitutes the coordinated water partly or wholly, so that a content of the coordinated water is decreased or even eliminated, therefore, the water absorption performance of the prussian blue analogue positive electrode material will be decreased significantly, in turn the performance of the electrochemical energy storage device is significantly improved.
1. A prussian blue analogue positive electrode material, wherein
a molecular formula of the prussian blue analogue positive electrode material is A x M c [M′(CN) 6 ] 1-y (b-H 2 O) 6y-d L d ·(i-H 2 O) z ;
where,
A is one or more selected from a group consisting of alkali metal cation, alkaline-earth metal cation, Zn 2+ and Al 3+ ;
M is a metal with the valence of 2+ or 3+;
M′ is a metal with the valence of 2+ or 3+;
b-H 2 O is a coordinated water;
L is a neutral ligand, the neutral ligand is one or more selected from a group consisting of CH 3 CN, NH 3 , CO and C 5 H 5 N;
i-H 2 O is an interstitial water;
0<x≤2;
0<c≤1;
0<y<1;
0<d≤6y;
0≤z≤16.
2. The prussian blue analogue positive electrode material according to claim 1 , wherein A is one or more selected from a group consisting of Li + , Na + , K + , Ca 2+ , Mg 2+ , Zn 2+ and Al 3+ .
3. The prussian blue analogue positive electrode material according to claim 1 , wherein M is a transition metal.
4. The prussian blue analogue positive electrode material according to claim 3 , wherein M is one or more selected from a group consisting of Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Nb, Ru, Sn, In and Cd.
5. The prussian blue analogue positive electrode material according to claim 1 , wherein M′ is a transition metal.
6. The prussian blue analogue positive electrode material according to claim 5 , wherein M′ is one or more selected from a group consisting of Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Nb, Ru, Sn, In and Cd.
7. A preparation method of a prussian blue analogue positive electrode material for preparing the prussian blue analogue positive electrode material according to claim 1 , comprising steps of:
placing a positive electrode material with a molecular formula of A x M c [M′(CN) 6 ] 1-y (b-H 2 O) 6y-d (i-H 2 O) z which is prepared in advance into an environment of a neutral ligand L, then making ligand exchange performed to obtain a prussian blue analogue positive electrode material with a molecular formula of A x M c [M′(CN) 6 ] 1-y (b-H 2 O) 6y-d L d (i-H 2 O) z ;
where,
A is one or more selected from a group consisting of alkali metal cation, alkaline-earth metal cation, Zn 2+ and Al 3+ ;
M is a metal with the valence of 2+ or 3+;
M′ is a metal with the valence of 2+ or 3+;
b-H 2 O is a coordinated water;
L is the neutral ligand, the neutral ligand is one or more selected from a group consisting of CH 3 CN, NH 3 , CO and C 5 H 5 N;
i-H 2 O is an interstitial water;
0<x≤2;
0<c≤1;
0<y<1;
0<d≤6y;
0≤z≤16.
8. The preparation method of the prussian blue analogue positive electrode material according to claim 7 , wherein the environment of the neutral ligand L is a solution containing the neutral ligand L or a gas containing the neutral ligand L.
9. The preparation method of the prussian blue analogue positive electrode material according to claim 8 , wherein the solution containing the neutral ligand L is a liquid formed by the neutral ligand L itself, an aqueous solution containing the neutral ligand L or a mixed solution of water and an organic solvent containing the neutral ligand L.
10. The preparation method of the prussian blue analogue positive electrode material according to claim 9 , wherein the organic solvent is one or more selected from a group consisting of methanol, ethanol, acetone, DMF, DMSO, tetrahydrofuran, n-propanol, isopropanol, ethylene glycol and propylene glycol.
11. The preparation method of the prussian blue analogue positive electrode material according to claim 8 , wherein the gas containing neutral ligand L is a gas formed just by the neutral ligand L itself or a mixed gas formed by the neutral ligand L and an inert gas.
12. The preparation method of the prussian blue analogue positive electrode material according to claim 11 , wherein the inert gas is one or more selected from a group consisting of N 2 , CO 2 , Ar and He.
13. A electrochemical energy storage device, comprising:
a positive electrode plate comprising a positive electrode current collector and a positive electrode film which is provided to the positive electrode current collector and contains a positive electrode material;
a negative electrode plate; and
a separator;
wherein,
the positive electrode material comprises the prussian blue analogue positive electrode material according to claim 1 .
14. The electrochemical energy storage device according to claim 13 , wherein the electrochemical energy storage device is a lithium-ion battery, a sodium-ion battery, a potassium-ion battery, a zinc-ion battery or an aluminum-ion battery.