In-situ polymerized polymer electrolyte for lithium ion batteries
Monomers for preparing a polymer electrolyte precursor composition capable to form an in-situ polymerized polymer electrolyte, which comprise, consist essentially of, or consist of A1) a first monomer and A2) a second monomer. A polymer electrolyte precursor raw material composition, a polymer electrolyte precursor composition capable to form a polymer electrolyte comprising the monomers, a polymer electrolyte and an electrochemical device are also provided.
1. Monomers for preparing a polymer electrolyte precursor composition capable to form an in-situ polymerized polymer electrolyte, which consists of:
A1) a first monomer represented by formula (I);
wherein R represents H, F, methyl or ethyl; and
A2) a second monomer, represented by formula (II);
wherein R represents methyl, —CH 2 OH, ethyl, or —CH 2 CH 2 OH; a, b, c each independently represents 0, 1, 2 or 3, and a+b+c≥2;
wherein the mass ratio of the first monomer and the second monomer is 20:0.5-20:10.
2. A polymer electrolyte precursor raw material composition for preparing a polymer electrolyte precursor composition capable to form an in-situ polymerized polymer electrolyte, which consists of:
A) monomers of claim 1 ; and
B) a free radical initiator for thermal polymerization reaction of the monomers.
3. A polymer electrolyte precursor composition capable to form an in-situ polymerized polymer electrolyte, which consists of:
A) monomers of claim 1 ;
B) a free radical initiator for thermal polymerization reaction of the monomers; and
C) a lithium salt, preferably lithium bis(trifluoromethanesulfonyl) imide.
4. The polymer electrolyte precursor composition of claim 3 , wherein the amount of the monomers is 5-80 wt. % based on the total weight of the polymer electrolyte precursor composition.
5. A method to in-situ prepare a polymer electrolyte, comprising the steps as follows:
1) injecting the polymer electrolyte precursor composition of claim 3 into a battery case with an electrode assembly, followed by sealing; and
2) Polymerizing in-situ the polymer electrolyte precursor composition by heating.
6. A polymer electrolyte, wherein the polymer electrolyte is formed by a polymer electrolyte precursor composition of claim 3 .
7. A polymer electrolyte for rechargeable batteries, comprising a polymer which is the reaction product of the monomers of claim 1 with a free radical initiator.
8. A polymer electrolyte for rechargeable batteries, comprising:
(i) a polymer which is the reaction product of the monomers of claim 1 with a free radical initiator, and
(ii) an organic solvent which contains an amount of an ionic salt effective to achieve an ionic conductivity of about 0.44 mS/cm or less.
9. A rechargeable battery comprising an anode, a cathode, a microporous separator separating said anode and said cathode, and a gel polymer electrolyte according to claim 6 .
10. A lithium ion battery comprising the polymer electrolyte prepared in-situ by the polymer electrolyte precursor composition of claim 3 .
11. An electrochemical device comprising the polymer electrolyte according to claim 6 .
12. A device fabricated by a process comprising:
preparing an installed battery case with an electrode assembly;
injecting the polymer electrolyte precursor composition of claim 3 into the battery case, followed by sealing; and
polymerizing the polymer electrolyte precursor composition.
13. A polymer electrolyte precursor composition capable to form a polymer electrolyte, consisting of:
A) monomers consisting of vinylene carbonate and trimethylolpropane ethoxylate triacrylate;
B) a free radical initiator, with an amount of 0.1-3 wt. % based on the total weight of the vinylene carbonate and trimethylolpropane ethoxylate triacrylate;
C) lithium bis(trifluoromethanesulfonyl) imide; and
D) ethylene carbonate/dimethyl carbonate;
wherein the amount of the vinylene carbonate and trimethylolpropane ethoxylate triacrylate is 25-75 wt. % based on the total weight of the polymer electrolyte precursor composition; and the mass ratio of vinylene carbonate and trimethylolpropane ethoxylate triacrylate is around 20:2-20:5.
14. Monomers for preparing a polymer electrolyte precursor composition capable to form an in-situ polymerized polymer electrolyte of claim 1 , wherein the first monomer is vinylene carbonate.
15. Monomers for preparing a polymer electrolyte precursor composition capable to form an in-situ polymerized polymer electrolyte of claim 1 , wherein the second monomer is trimethylolpropane ethoxylate triacrylate.
16. Monomers for preparing a polymer electrolyte precursor composition capable to form an in-situ polymerized polymer electrolyte of claim 1 , wherein a+b+c≥3.
17. Monomers for preparing a polymer electrolyte precursor composition capable to form an in-situ polymerized polymer electrolyte of claim 1 , wherein the mass ratio of the first monomer and the second monomer is 20:3-20:5.
18. The polymer electrolyte of claim 3 , wherein the lithium salt is bis(trifluoromethanesulfonyl) imide.
19. The polymer electrolyte of claim 3 , further comprising an organic solvent with an amount of 0%-70 wt. % based on the total weight of the polymer electrolyte precursor composition.
20. The polymer electrolyte of claim 19 , wherein the organic solvent is ethylene carbonate/dimethyl carbonate.
21. The polymer electrolyte of claim 19 , wherein the amount of the organic solvent is 20%-50 wt. % based on the total weight of the polymer electrolyte precursor composition.