Solid-liquid electrolyte for use in a battery
The present invention provides a solid-liquid electrolyte in the form of a gel which comprises an organic carbonate-based solvent, precipitated silica, at least one ionically conducting salt and optionally additives. The invention also relates to batteries containing said solid-liquid electrolyte. The solid-liquid electrolyte according to the present invention can improve the electrochemical properties of batteries and prevent electrolyte leakage thus reducing the risk of corrosion of the batteries.
1. A solid-liquid electrolyte in the form of a gel comprising:
at least one ionically conducting salt,
at least one organic carbonate-based solvent, and
precipitated silica.
2. The solid-liquid electrolyte of claim 1 wherein the precipitated silica is in particulate form.
3. The solid-liquid electrolyte according to claim 1 , wherein the precipitated silica has a BET specific surface area of between 100 and 650 m 2 /g.
4. The solid-liquid electrolyte according to claim 1 , wherein the precipitated silica is present in an amount by weight of from 1.0% to 25.0% relative to the total weight of the electrolyte.
5. The solid-liquid electrolyte of claim 4 wherein the silica is present in an amount by weight comprised in the range of from 1.0% to 8.0% relative to the total weight of the electrolyte.
6. The solid-liquid electrolyte of claim 4 , wherein the precipitated silica is present in an amount by weight comprised in the range of from 8.0% to 25.0%, relative to the total weight of the electrolyte.
7. The solid-liquid electrolyte of claim 4 wherein the precipitated silica is present in an amount by weight comprised in the range of from 20.0% to 25.0% relative to the total weight of the electrolyte.
8. The solid-liquid electrolyte of claim 5 , wherein the precipitated silica has a BET specific surface of from 100 to 270 m 2 /g.
9. The solid-liquid electrolyte of claim 7 , wherein the silica has a BET specific surface of from 300 to 650 m 2 /g.
10. The solid-liquid electrolyte of claim 1 , wherein the precipitated silica has a median particle size from 3.0 to 80.0 μm.
11. The solid-liquid electrolyte of claim 1 , wherein the at least one ionically conducting salt is selected from the group consisting of:
(a) Mel, Me(PF 6 ), Me(BF 4 ), Me(ClO 4 ), Me-bis(oxalato)borate, MeCF 3 SO 3 , Me[N(CF 3 SO 2 ) 2 ],
Me[N(C 2 F 5 SO 2 ) 2 ], Me[N(CF 3 SO 2 )], wherein R F is C 2 F 5 , C 4 F 9 or CF 3 OCF 2 CF 2 , Me(AsF 6 ), Me[C(CF 3 SO 2 ) 3 ], Me 2 S, Me being Li or Na;
(b)
wherein R′ F is selected from the group consisting of F, CF 3 , CHF 2 , CH 2 F, C 2 HF 4 , C 2 H 2 F 3 , C 2 H 3 F 2 , C 2 F 5 , C 3 F 7 , C 3 H 2 F 5 , C 3 H 4 F 3 , C 4 F 9 , C 4 H 2 F 7 , C 4 H 4 F 5 , C 5 F 11 , C 3 F 5 OCF 3 , C 2 F 4 OCF 3 , C 2 H 2 F 2 OCF 3 and CF 2 OCF 3 , and
(c) mixtures thereof.
12. The solid-liquid electrolyte of claim 1 , wherein the at least one ionically conducting salt is selected from the group consisting of LiPF 6 , LiBF 4 , LiClO 4 , lithium bis(oxalato)borate (“LiBOB”), LiN(CF 3 SO 2 ) 2 , LiN(C 2 F 5 SO 2 ) 2 , Li[N(CF 3 SO 2 )(R F SO 2 )] n , with R F being C 2 F 5 , C 4 F 9 , or CF 3 OCF 2 CF 2 , LiAsF 6 , LiC(CF 3 SO 2 ) 3 and mixtures thereof.
13. The solid-liquid electrolyte of claim 1 , wherein the at least one organic carbonate-based solvent include unsaturated cyclic carbonates and unsaturated acyclic carbonates.
14. The solid-liquid electrolyte of claim 1 , wherein the at least one organic carbonate-based solvent is a mixture of at least one unsaturated acyclic carbonate and at least one unsaturated cyclic carbonate.
15. An electronic device comprising the solid-liquid electrolyte according to claim 1 .
16. The electronic device according to claim 15 which is a battery.
17. The battery according to claim 16 wherein the solid-liquid electrolyte is applied in the form of a layer between a positive electrode and a negative electrode of the battery.
18. A separator-free secondary battery containing the solid-liquid electrolyte according to claim 6 .
19. The solid-liquid electrolyte of claim 13 , wherein the at least one organic carbonate-based solvent is selected from the group consisting of ethylene carbonate, propylene carbonate, butylene carbonate, fluoroethylene carbonate, fluoropropylene carbonate, dimethylcarbonate, diethylcarbonate, ethylmethylcarbonate, dimethylethane and mixture thereof.
20. The solid-liquid electrolyte of claim 14 , wherein the at least one organic carbonate-based solvent is a mixture of ethylene carbonate and dimethylcarbonate.