Electrolytes for wide operating temperature lithium-ion cells

Patent metadata

Field	Value
Publication number	US-2016197378-A1
Application number	US-201615044637-A
Country	US
Kind code	A1
Filing date	Feb 16, 2016
Priority date	Apr 8, 2008
Publication date	Jul 7, 2016
Grant date	—

Abstract

Provided herein are electrolytes for lithium-ion electrochemical cells, electrochemical cells employing the electrolytes, methods of making the electrochemical cells and methods of using the electrochemical cells over a wide temperature range. Included are electrolyte compositions comprising a lithium salt, a cyclic carbonate, a non-cyclic carbonate, and a linear ester and optionally comprising one or more additives.

First claim

We claim:

1 . An electrolyte for use in an electrochemical cell, the electrolyte comprising a mixture of:
10-40% by volume cyclic carbonate, wherein the cyclic carbonate is a non-fluorinated cyclic carbonate; 10-50% by volume non-cyclic carbonate; 20-80% by volume linear ester; a lithium salt in a concentration from 0.5 M to 1.5 M; and
lithium oxalate.

2 . The electrolyte of claim 1 , wherein the electrolyte comprises wherein the mixture comprises 15-30% by volume of the cyclic carbonate, 15-30% by volume of the non-cyclic carbonate, and 40-70% by volume of the linear ester.

3 . The electrolyte of claim 2 , wherein the cyclic carbonate, the non-cyclic carbonate and the linear ester are present in a combined total volume of 100 vol % and the lithium oxalate is present at a concentration between 0.5-3 vol % relative to the total volume.

4 . The electrolyte of claim 3 , wherein the non-fluorinated cyclic carbonate is EC, the non-cyclic carbonate is selected from ethyl methyl carbonate (EMC), dimethyl carbonate (DMC), diethyl carbonate (DEC), methyl propyl carbonate (MPC) or combinations thereof, the lithium salt includes LiPF 6 in a concentration from 0.8 to 1.20 M and the linear ester is selected from:
(i) methyl propionate; (ii) ethyl propionate; (iii) methyl butyrate; (iv) ethyl butyrate; (v) propyl butyrate; (vi) butyl butyrate; or (vii) a combination of (i), (ii), (iii), (iv), (v) and/or (vi).

5 . The electrolyte of claim 4 , wherein at least two linear esters are present, a first linear ester selected from the group consisting of methyl propionate, ethyl propionate, methyl butyrate and ethyl butyrate and a second linear ester selected from the group consisting of propyl butyrate and butyl butyrate.

6 . The electrolyte of claim 1 further comprising an additive selected from:
(i) lithium bis(oxalato)borate (LiBOB);
(ii) vinylene carbonate (VC);
(iii) lithium difluoro(oxolato) borate (LiDFOB); or
(iv) a combination of (i), (ii) and (iii).

7 . An electrolyte for use in an electrochemical cell, the electrolyte comprising a mixture of:
10-40% by volume cyclic carbonate, wherein the cyclic carbonate is a non-fluorinated saturated cyclic carbonate;
10-50% by volume non-cyclic carbonate;
20-80% by volume linear ester;
a lithium salt in a concentration from 0.5 M to 1.5 M, the lithium salt including lithium bis(oxalato)borate (LiBOB),

wherein the electrolyte does not include a fluorinated ester.

8 . The electrolyte of claim 7 , wherein the electrolyte comprises wherein the mixture comprises 15-30% by volume of the cyclic carbonate, 15-30% by volume of the non-cyclic carbonate, and 40-70% by volume of the linear ester.

9 . The electrolyte of claim 8 , wherein the LiBOB is present in a concentration from 0.05 M to 0.25 M.

10 . The electrolyte of claim 9 , wherein the non-fluorinated cyclic carbonate is EC, the non-cyclic carbonate is selected from ethyl methyl carbonate (EMC), dimethyl carbonate (DMC), diethyl carbonate (DEC), methyl propyl carbonate (MPC) or combinations thereof, the lithium salt includes LiPF 6 in a concentration from 0.8 to 1.20 M and the linear ester is selected from:
(i) methyl propionate; (ii) ethyl propionate; (iii) methyl butyrate; (iv) ethyl butyrate; (v) propyl butyrate; (vi) butyl butyrate; or (vii) a combination of (i), (ii), (iii), (iv), (v) and/or (vi).

11 . The electrolyte of claim 10 , wherein at least two linear esters are present, a first linear ester from the group consisting of methyl propionate, ethyl propionate, methyl butyrate and ethyl butyrate and a second linear ester selected from the group consisting of propyl butyrate and butyl butyrate.

12 . The electrolyte of claim 7 further comprising an additive selected from:
(i) lithium oxalate;
(ii) vinylene carbonate (VC);
(iii) lithium difluoro(oxolato) borate (LiDFOB); or
(iv) a combination of (i), (ii) and (iii).

13 . An electrochemical cell comprising:
an anode; a cathode; and the electrolyte of claim 1 provided between the anode and the cathode.

14 . The electrochemical cell of claim 13 , wherein the cathode comprises a material selected from LiCoO 2 , LiMn 2 O 4 , LiMPO 4 (M=Fe, Co, Mn), LiNiCoAlO 2 , LiNi 0.33 Co 0.33 Mn 0.33 O 2 , LiNiCoO 2 , LiNi 0.8 Co 0.2 O 2 , Li(Li 0.17 Ni 0.25 Mn 0.58 )O 2 , layered-layered composite LiNiCoMnO 2 or LiNi 0.5 Mn 1.5 O 4 .

15 . The electrochemical cell of claim 13 , wherein the anode comprises a material selected from natural graphite, synthetic graphite, hard carbon, mesocarbon microbeads (MCMB), silicon-carbon composites, lithium titanate (Li 4 Ti 5 O 12 ), lithium metal and combinations thereof.

16 . The electrochemical cell of claim 13 wherein the anode is a carbon-based anode and the cathode is selected from a layered-layered composite of LiNiCoMnO 2 , LiNi 0.5 Mn 1.5 O 4 or LiNi 0.33 Co 0.33 Mn 0.33 O 2 .

17 . An electrochemical cell comprising:
an anode; a cathode; and the electrolyte of claim 7 provided between the anode and the cathode.

18 . The electrochemical cell of claim 17 , wherein the cathode comprises a material selected from LiCoO 2 , LiMn 2 O 4 , LiMPO 4 (M=Fe, Co, Mn), LiNiCoAlO 2 , LiNi 0.33 CO 0.33 Mn 0.33 O 2 , LiNiCoO 2 , LiNi 0.8 Co 0.2 O 2 , Li(Li 0.17 Ni 0.25 Mn 0.58 )O 2 , layered-layered composite LiNiCoMnO 2 or LiNi 0.5 Mn 1.5 O 4 .

19 . The electrochemical cell of claim 17 , wherein the anode comprises a material selected from natural graphite, synthetic graphite, hard carbon, mesocarbon microbeads (MCMB), silicon-carbon composites, lithium titanate (Li 4 Ti 5 O 12 ), lithium metal and combinations thereof.

20 . The electrochemical cell of claim 17 wherein the anode is a carbon-based anode and the cathode is selected from a layered-layered composite of LiNiCoMnO 2 , LiNi 0.5 Mn 1.5 O 4 or LiNi 0.33 Co 0.33 Mn 0.33 O 2 .

21 . A method of making an electrochemical cell comprising the steps of:
providing a cathode; providing an anode; and providing the electrolyte of claim 1 between the cathode and the anode.

22 . A method of making an electrochemical cell comprising the steps of:
providing a cathode; providing an anode; and providing the electrolyte of claim 7 between the cathode and the anode.

23 . A method of generating an electrical current, the method comprising the steps of:
providing an electrochemical cell according to claim 13 , the cell being in a charged state; and discharging the electrochemical cell.

24 . A method of generating an electrical current, the method comprising the steps of:
providing an electrochemical cell according to claim 17 , the cell being in a charged state; and discharging the electrochemical cell.

Assignees

• California Inst Of Techn

Inventors

• Smart Marshall C
• Bugga Ratnakumar V

Classifications

• H01M4/587

  for inserting or intercalating light metals · CPC title

• H01M4/525

  of mixed oxides or hydroxides containing iron, cobalt or nickel for inserting or intercalating light metals, e.g. LiNiO2, LiCoO2 or LiCoOxFy · CPC title

• H01M4/382

  Lithium (H01M4/405 takes precedence) · CPC title

• H01M10/0525

  Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries · CPC title

• H01M4/505

  of mixed oxides or hydroxides containing manganese for inserting or intercalating light metals, e.g. LiMn2O4 or LiMn2OxFy · CPC title