Electrolyte, electrochemical device and electronic device

1 . An electrochemical device comprising:

a cathode;

an anode comprising an anode active substance;

an isolation film disposed between the cathode and the anode; and

an electrolyte, wherein the electrolyte comprises a fluoroethylene carbonate and a P—N bond-containing compound; and the P—N bond-containing compound comprises a compound having a structure shown in Formula I:

wherein R 0 represents O n , wherein n is 0 or 1;

R 1 , R 2 , R 3 , R 4 , R 5 , and R 6 are each independently selected from C 1 -C 6 alkyl, C 2 -C 6 alkenyl, C 2 -C 6 alkynyl, or C 1 -C 6 alkoxy;

or R 1 and R 2 , R 3 and R 4 , or R 5 and R 6 are interconnected to form, together with an N atom, a cyclic group with 2-5 carbon atoms; and

based on a mass of the electrolyte, a mass percentage of the fluoroethylene carbonate in the electrolyte is a %, a mass percentage of the P—N bond-containing compound in the electrolyte is b %, and 0.1≤a/b≤200;

wherein a ratio W:K is in a range of 0.12 to 1.15, W represents a content value of the compound of Formula I required per unit capacity in units of g/Ah,

K represents a value of a specific surface area per unit mass of the anode active substance in units of m 2 /g, and 1.0≤K≤2.0.

2 . The electrochemical device according to claim 1 , wherein the compound having the structure shown in Formula I comprises at least one of a compound shown in Formula I-A or a compound shown in Formula I-B:

wherein A 1 , A 2 , and A 3 are each independently selected from a carbon atom, an oxygen atom, or a single bond.

3 . The electrochemical device according to claim 1 , wherein the P—N bond-containing compound comprises at least one of compounds shown below:

4 . The electrochemical device according to claim 1 , wherein based on the mass of the electrolyte, the mass percentage of the P—N bond-containing compound in the electrolyte is 0.1%-5%, and the mass percentage of the fluoroethylene carbonate in the electrolyte is 0.5%-15%.

5 . The electrochemical device according to claim 1 , wherein the electrolyte further comprises a sulfur-containing compound shown in Formula II:

wherein R 21 and R 22 are each independently selected from straight-chain or branched-chain substituted or unsubstituted C 1 -C 6 alkyl, substituted or unsubstituted C 3 -C 6 cycloalkyl, substituted or unsubstituted C 1 -C 6 alkoxy, substituted or unsubstituted C 2 -C 6 alkenyl, substituted or unsubstituted C 2 -C 6 alkynyl, sulfuryl, silyl, a cyano group, or R 23 O—; a substituent group is a halogen atom; and R 23 is C 1 -C 6 alkyl, substituted or unsubstituted C 3 -C 6 cycloalkyl, or substituted or unsubstituted C 3 -C 6 heterocyclyl;

or R 21 and R 22 are interconnected to form, together with the sulfuryl, a substituted or unsubstituted cyclic group with 3-4 carbon atoms, wherein based on the mass of the electrolyte, a mass percentage of the sulfur-containing compound in the electrolyte is 1%-6%.

6 . The electrochemical device according to claim 5 , wherein the sulfur-containing compound comprises one or more of the following compounds:

7 . The electrochemical device according to claim 1 , wherein the electrolyte further comprises a phosphoric acid cyclic anhydride compound, and the phosphoric acid cyclic anhydride compound comprises a compound shown in Formula III:

wherein R 31 , R 32 , and R 33 are each independently selected from H, substituted or unsubstituted C 1 -C 5 saturated alkyl, substituted or unsubstituted C 2 -C 10 unsaturated alkyl, or a C 6 -C 18 aromatic ring.

8 . The electrochemical device according to claim 7 , wherein the phosphoric acid cyclic anhydride compound comprises one or more of the following compounds:

9 . The electrochemical device according to claim 7 , wherein based on the mass of the electrolyte, a mass percentage of the phosphoric acid cyclic anhydride compound in the electrolyte is 0.1%-3%.

10 . The electrochemical device according to claim 1 , wherein the electrolyte further comprises a tricarbonitrile compound, the tricarbonitrile compound comprises at least one of 1,3,5-pentanetricarbonitrile, 1,3,6-hexanetricarbonitrile, 1,2,6-hexanetricarbonitrile or 1,2,3-tris(2-cyanoethoxy)propane; and based on the mass of the electrolyte, a mass percentage of the tricarbonitrile compound in the electrolyte is 0.1%-6%.

11 . The electrochemical device according to claim 1 , wherein the ratio W:K is in a range of 0.5 to 1.15.

12 . The electrochemical device according to claim 1 , wherein the ratio W:K is in a range of 0.12 to 0.8.

13 . An electronic device, comprising the electrochemical device according to claim 1 .