EP3596092A1 - Calcium salts - Google Patents

Calcium salts

Info

Publication number
EP3596092A1
EP3596092A1 EP18714016.5A EP18714016A EP3596092A1 EP 3596092 A1 EP3596092 A1 EP 3596092A1 EP 18714016 A EP18714016 A EP 18714016A EP 3596092 A1 EP3596092 A1 EP 3596092A1
Authority
EP
European Patent Office
Prior art keywords
salt
crown
ligand
general formula
ether
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP18714016.5A
Other languages
German (de)
French (fr)
Inventor
Evan Keyzer
Clare GREY
Dominic Wright
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Dyson Technology Ltd
Original Assignee
Dyson Technology Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Dyson Technology Ltd filed Critical Dyson Technology Ltd
Publication of EP3596092A1 publication Critical patent/EP3596092A1/en
Withdrawn legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07D—HETEROCYCLIC COMPOUNDS
    • C07D323/00—Heterocyclic compounds containing more than two oxygen atoms as the only ring hetero atoms
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/054—Accumulators with insertion or intercalation of metals other than lithium, e.g. with magnesium or aluminium
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01F—COMPOUNDS OF THE METALS BERYLLIUM, MAGNESIUM, ALUMINIUM, CALCIUM, STRONTIUM, BARIUM, RADIUM, THORIUM, OR OF THE RARE-EARTH METALS
    • C01F11/00—Compounds of calcium, strontium, or barium
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07F—ACYCLIC, CARBOCYCLIC OR HETEROCYCLIC COMPOUNDS CONTAINING ELEMENTS OTHER THAN CARBON, HYDROGEN, HALOGEN, OXYGEN, NITROGEN, SULFUR, SELENIUM OR TELLURIUM
    • C07F3/00—Compounds containing elements of Groups 2 or 12 of the Periodic Table
    • C07F3/04—Calcium compounds
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07F—ACYCLIC, CARBOCYCLIC OR HETEROCYCLIC COMPOUNDS CONTAINING ELEMENTS OTHER THAN CARBON, HYDROGEN, HALOGEN, OXYGEN, NITROGEN, SULFUR, SELENIUM OR TELLURIUM
    • C07F9/00—Compounds containing elements of Groups 5 or 15 of the Periodic Table
    • C07F9/02—Phosphorus compounds
    • C07F9/28—Phosphorus compounds with one or more P—C bonds
    • C07F9/535—Organo-phosphoranes
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/056—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/056—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes
    • H01M10/0564—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes the electrolyte being constituted of organic materials only
    • H01M10/0566—Liquid materials
    • H01M10/0568—Liquid materials characterised by the solutes
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M2300/00—Electrolytes
    • H01M2300/0017—Non-aqueous electrolytes
    • H01M2300/0025—Organic electrolyte
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10—Energy storage using batteries

Definitions

  • the present invention relates to a salt of calcium hexafluorophosphate. Additionally, the present invention relates to a method of making a calcium hexafluorophosphate salt and the use of the calcium hexafluorophosphate salt in an electrolyte in a cell or battery.
  • Lithium-ion batteries are currently used in a variety of electronic devices.
  • the use of lithium-ion cells has prevailed over other battery technologies due to the ability of a lithium-ion cell to be recharged without a loss of a significant charge capacity in the short term.
  • the energy density of a lithium-ion battery enables its use in portable products such as laptop computers and mobile phones. Over time however, lithium batteries are known to suffer from loss of charge capacity. Furthermore, issues of thermal runaway and overheating risks have been widely reported.
  • LiPF 6 is the preferred electrolyte salt in lithium-ion cells due to its balance of several properties that no other lithium salt has been found to possess.
  • there are concerns over the long term use of lithium cells given the relatively low abundance of lithium in the Earth's crust and the current high price of lithium relative to other Alkali and Alkaline Earth metals.
  • the present invention provides salt of the general formula:
  • each L represents a ligand selected from one of the following compounds: an ether or aza macrocyclic; a halomethane or a nitrile of the general formula R-C ⁇ N.
  • alkaline earth metals such as calcium could be used as electrolyte solutions in electrochemical cells and batteries.
  • Calcium is the fifth most Earth- abundant element and therefore has a relatively low cost per ton compared to lithium.
  • calcium has a higher charge capacity than lithium.
  • the large ionic radius of a Ca 2+ ion, and thus lower charge density with respect to Mg 2+ and Al 3+ could permit faster solid-state diffusion into electrode materials, in electrodes with appropriately sized voids within the structure, an issue that has limited the construction of efficient Mg-ion batteries so far.
  • calcium has not been widely adopted as an electrolyte or as a material for anodes because of difficulties in forming electrolytes that are stable over a wide voltage range and also compatible with multiple electrodes.
  • the lithium hexafluorophosphate salt is the preferred electrolyte salt in lithium-ion cells.
  • a barrier for using a calcium hexafluorophosphate based electrolyte in calcium-ion batteries is the fact that the synthesis of an Alkaline Earth metal hexafluorophosphate salt can be costly and more problematic (often resulting in lower purity materials) when compared with the synthesis of a lithium hexafluorophosphate salt. It has been found however that the calcium hexafluorophosphate salt of the present invention can be readily synthesised in an anhydrous solution under relatively mild conditions.
  • L may represent a ligand selected from one only of the following compounds: a cyclic crown ether; an aza macrocyclic compound; a halomethane; or a nitrile of the general formula R-C ⁇ N. That is to say that L may comprise one or more cyclic crown ethers, one or more aza macrocyclic compounds, two or more halomethanes, or two or more nitriles of the general formula R-C ⁇ N.
  • the ether or aza macrocyclic can comprise typical cyclic crown ethers selected from one of the following: [12]-crown-4, [15]-crown-5, [18]-crown-6, [24]-crown-8.
  • the cyclic crown ether may be used to sequester, or partly sequester the calcium cation.
  • the aza macrocyclic compound may be cyclen or cyclam.
  • the use of a multidentate ligand can be favourable since the calcium cation remains in solution but has a lowered reactivity and could also inhibit the decomposition of the PF 6 ion during synthesis; and plating of calcium onto an electrode surface if the salt is used in an electrolyte in a calcium-ion cell.
  • each R may represent an organic group independently selected from the following: methyl, ethyl, propyl, butyl, 'butyl, pentyl, ethylene, propylene, butylene, pentylene, toluene, naphthalene, or phenyl.
  • a sterically bulky ligand could prevent the solvation of the calcium cation. Therefore for the general formula, R may preferably represents a group that would provide a nitrile that is considered to have low sterically hindrance.
  • Each L may be the same nitrile. This renders the synthesis of the salt more straightforward since the same nitrile solution can be used in both the activation and the treatment steps.
  • L may be acetonitrile, which is the least sterically hindered nitrile.
  • acetonitrile provides good solvation of the calcium cation, as well as low manufacturing expense since desolvation under high vacuum can be more easily achieved than with other solvents.
  • This desolvated salt could then be re-solvated with, for instance, an ether (such as THF, diethyl ether) or another donor solvent.
  • the halomethane may be a chlorinated methane, such as CH 2 CI 2 , CHCI 3 , CCI4.
  • the chloromethanes represent stable and cost effective dry solvents for the synthesis.
  • Dichloromethane (CH 2 CI 2 ) is particularly suited as a ligand and solvent for the synthesis of the magnesium salt due to its low boiling point and solvating characteristics.
  • a single crystal obtained from the diffusion of Et 2 0 in to a CH 3 CN solution of the salt of the present invention may have the general formula (Cac l5-crown-5) 4 (PF 6 )8(CH3CN)2.
  • the present invention provides a method of making a salt of the general formula:
  • L y represents a ligand independently selected from any one of the following compounds: an ether or aza macrocyclic; a halomethane or a nitrile of the general formula R-C ⁇ N; and L y comprises a mixture of compounds Li and L2; the method comprising: providing Ca metal, washing and activating the Ca metal in a first dry solution comprising a first compound (Li), treating the solution of activated Ca metal and first compound Li with NOPF 6 in a second dry solution comprising a second compound (L 2 ), removing the residual solvent, and recrystallizing the remaining solid to form the salt of Formula (ii).
  • the residual solvent can be removed by evaporation, for example, under vacuum or by heating.
  • the present invention provides an electrolyte comprising a salt in accordance with the above Formula (i) or Formula (ii).
  • the electrolyte may comprise the salt as an additive to a conventional electrolyte, or the salt may be used in a pure solution to form, with an appropriate solvent, an electrolyte by itself.
  • the present invention provides a cell or battery with an electrolyte comprising a salt in accordance with the above Formula (i) or Formula (ii).
  • the salts of the present invention do not suffer from some of the same disadvantages observed with the use of lithium salts in electrochemical cells or batteries.
  • the salt of the present invention may be useful in terms of reducing or limiting the corrosion of cell components.
  • Figure 1 is an X-ray crystal structure of a salt crystal of the present invention selected from bulk solution;
  • Figure 2 is an X-ray crystal structure of another salt crystal falling outside the scope of the present invention.
  • FIG. 3 is a X H NMR spectrum of a salt of the present invention
  • Figure 4 is a 19 F NMR spectrum of a salt of the present invention
  • Figure 5 is a 31 P NMR spectrum of a salt of the present invention.
  • Elemental microanalytical data were obtained from the University of Cambridge, Department of Chemistry microanalytical service. Analysis calculated for C64Hi32Ca4F48N 4 024P8 [(Cac 15-crown-5) 4 (PF 6 ) 8 (CH 3 CN)2 ⁇ (2 CH 3 CN, 4 Et 2 0)]: C, 28.9; H, 5.0; N, 2.1; found: C, 28.5; H, 4.9; N, 2.3.
  • Figure 2 shows the X-ray crystal stuture of another crystal obtained from the diffusion of Et 2 0 in to a CH 3 CN solution.
  • X-ray analysis was carried out on data collected with a Bruker D8 Quest CCD diffractometer and confirmed the complex to be an undesired salt (Figure 2).
  • the structure relates to [(Cac l5-crown- 5) 4 (SiF 6 )2(CH3CN) 2 ] 4+ (PF 6 )4, where the two brid ging ions are SiFg .
  • the elemental analysis (C, H, and N) of this crystal was obtained using elemental microanalytical data obtained from the University of Cambridge, Department of Chemistry microanalytical service. Analysis calculated for C 36 H 69 Ca 2 F 24 N 3 0i 5 P 4 : C, 29.95; H, 4.82; N, 2.91 ; found: C, 29.81 ; H, 4.83; N, 2.48]
  • the 3 ⁇ 4 13 C, 19 F and 31 P NMR spectra of the bulk white crystalline powder of (Cac l5-crown- 5)(PF 6 )2 are shown in Figures 3 to 5, respectively.
  • the 19 F and 31 P NMR spectra exhibited a doublet and heptet, respectively, characteristic of the PF 6 anion.
  • NMR spectra were recorded at 298.0 K on a Bruker 500 MHz AVIII HD Smart Probe Spectrometer ( l at 500 MHz, 31 P 202 MHz, 19 F 471 MHz) or a Bruker 400 MHz AVIII HD Smart Probe spectrometer (*H at 400 MHz, 31 P 162 MHz, 19 F 376 MHz) unless otherwise specified.
  • Chemical shifts ( ⁇ , ppm) are given relative to residual solvent signals for X H, to external 85% H 3 PO4 for 31 P and to CCI 3 F for 19 F.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Inorganic Chemistry (AREA)
  • Electrochemistry (AREA)
  • Manufacturing & Machinery (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Materials Engineering (AREA)
  • Geology (AREA)
  • Physics & Mathematics (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • General Physics & Mathematics (AREA)
  • Health & Medical Sciences (AREA)
  • Biochemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • Molecular Biology (AREA)
  • Secondary Cells (AREA)

Abstract

A salt of the general formula: Ca(L)x(PF6)2 wherein each L is a ligand selected from an ether or aza macrocyclic; a halomethane or a nitrile of the general formula R-C≡N. The method of making the salt comprises the steps: providing Ca metal, activating the Ca metal in a first dry solution comprising a first ligand solution (L1), treating the dry solution of activated Ca metal and L1 with NOPF6 in a second dry solution comprising a second ligand solution (L2), heating the treated Ca metal solution removing residual solvent under vacuum, and recrystallizing the remaining solid to form the salt wherein L comprises a mixture of L1 and L2. The salt can be used as the salt in an electrolyte, or as an additive to an electrolyte, and the resulting electrolyte can be used in a calcium-ion cell or battery.

Description

CALCIUM SALTS
The present invention relates to a salt of calcium hexafluorophosphate. Additionally, the present invention relates to a method of making a calcium hexafluorophosphate salt and the use of the calcium hexafluorophosphate salt in an electrolyte in a cell or battery.
Lithium-ion batteries are currently used in a variety of electronic devices. The use of lithium-ion cells has prevailed over other battery technologies due to the ability of a lithium-ion cell to be recharged without a loss of a significant charge capacity in the short term. In addition, the energy density of a lithium-ion battery enables its use in portable products such as laptop computers and mobile phones. Over time however, lithium batteries are known to suffer from loss of charge capacity. Furthermore, issues of thermal runaway and overheating risks have been widely reported.
Many lithium-ion electrolyte systems have been developed and studied using a wide range of lithium salts including LiBF4, L1CIO4, LiNTF2, LiPF6, LiAsF6, and LiSbF6 as well as others. LiPF6 is the preferred electrolyte salt in lithium-ion cells due to its balance of several properties that no other lithium salt has been found to possess. However, there are concerns over the long term use of lithium cells, given the relatively low abundance of lithium in the Earth's crust and the current high price of lithium relative to other Alkali and Alkaline Earth metals.
In a first aspect, the present invention provides salt of the general formula:
Ca(L)x(PF6)2
(1)
wherein x represents a number between 0 and 6; and when x is not equal to 0, each L represents a ligand selected from one of the following compounds: an ether or aza macrocyclic; a halomethane or a nitrile of the general formula R-C≡N.
It has been recognised theoretically that alkaline earth metals such as calcium could be used as electrolyte solutions in electrochemical cells and batteries. Calcium is the fifth most Earth- abundant element and therefore has a relatively low cost per ton compared to lithium. In addition, calcium has a higher charge capacity than lithium. Furthermore, the large ionic radius of a Ca2+ ion, and thus lower charge density with respect to Mg2+ and Al3+, could permit faster solid-state diffusion into electrode materials, in electrodes with appropriately sized voids within the structure, an issue that has limited the construction of efficient Mg-ion batteries so far. However, despite this knowledge calcium has not been widely adopted as an electrolyte or as a material for anodes because of difficulties in forming electrolytes that are stable over a wide voltage range and also compatible with multiple electrodes.
As mentioned above, the lithium hexafluorophosphate salt is the preferred electrolyte salt in lithium-ion cells. However, a barrier for using a calcium hexafluorophosphate based electrolyte in calcium-ion batteries is the fact that the synthesis of an Alkaline Earth metal hexafluorophosphate salt can be costly and more problematic (often resulting in lower purity materials) when compared with the synthesis of a lithium hexafluorophosphate salt. It has been found however that the calcium hexafluorophosphate salt of the present invention can be readily synthesised in an anhydrous solution under relatively mild conditions.
The term salt used throughout the specification is intended to cover complex calcium salts with ligands (L) that fall within the general formula given above. The choice of ligand or mixture of ligands may allow for a more stable reaction mixture in the synthesis of the calcium hexafluorophosphate salt. Each ligand may be independently selected from an ether or aza macrocyclic, a halomethane or a nitrile compound. With a view to simplifying the reaction mixture during synthesis, L may represent a ligand selected from one only of the following compounds: a cyclic crown ether; an aza macrocyclic compound; a halomethane; or a nitrile of the general formula R-C≡N. That is to say that L may comprise one or more cyclic crown ethers, one or more aza macrocyclic compounds, two or more halomethanes, or two or more nitriles of the general formula R-C≡N.
The ether or aza macrocyclic can comprise typical cyclic crown ethers selected from one of the following: [12]-crown-4, [15]-crown-5, [18]-crown-6, [24]-crown-8. The cyclic crown ether may be used to sequester, or partly sequester the calcium cation. Furthermore, the aza macrocyclic compound may be cyclen or cyclam. The use of a multidentate ligand can be favourable since the calcium cation remains in solution but has a lowered reactivity and could also inhibit the decomposition of the PF6 ion during synthesis; and plating of calcium onto an electrode surface if the salt is used in an electrolyte in a calcium-ion cell. These ether or aza macrocyclic compounds can be used in combination with ether or nitrile based solvents without hindering the desired synthesis of the resultant calcium salt. In terms of the general formula for the nitrile, and when x is equal to 6, each R may represent an organic group independently selected from the following: methyl, ethyl, propyl, butyl, 'butyl, pentyl, ethylene, propylene, butylene, pentylene, toluene, naphthalene, or phenyl. A sterically bulky ligand could prevent the solvation of the calcium cation. Therefore for the general formula, R may preferably represents a group that would provide a nitrile that is considered to have low sterically hindrance.
Each L may be the same nitrile. This renders the synthesis of the salt more straightforward since the same nitrile solution can be used in both the activation and the treatment steps. For the salt, L may be acetonitrile, which is the least sterically hindered nitrile. As an added advantage, the use of acetonitrile provides good solvation of the calcium cation, as well as low manufacturing expense since desolvation under high vacuum can be more easily achieved than with other solvents. This desolvated salt could then be re-solvated with, for instance, an ether (such as THF, diethyl ether) or another donor solvent.
The halomethane may be a chlorinated methane, such as CH2CI2, CHCI3, CCI4. The chloromethanes represent stable and cost effective dry solvents for the synthesis. Dichloromethane (CH2CI2) is particularly suited as a ligand and solvent for the synthesis of the magnesium salt due to its low boiling point and solvating characteristics.
A single crystal obtained from the diffusion of Et20 in to a CH3CN solution of the salt of the present invention may have the general formula (Cac l5-crown-5)4(PF6)8(CH3CN)2.
In a second aspect, the present invention provides a method of making a salt of the general formula:
Ca(Ly)x(PF6)2
(11)
wherein x represent a number between 0 and 6, when x is not equal to zero, Ly represents a ligand independently selected from any one of the following compounds: an ether or aza macrocyclic; a halomethane or a nitrile of the general formula R-C≡N; and Ly comprises a mixture of compounds Li and L2; the method comprising: providing Ca metal, washing and activating the Ca metal in a first dry solution comprising a first compound (Li), treating the solution of activated Ca metal and first compound Li with NOPF6 in a second dry solution comprising a second compound (L2), removing the residual solvent, and recrystallizing the remaining solid to form the salt of Formula (ii).
The residual solvent can be removed by evaporation, for example, under vacuum or by heating.
In a third aspect, the present invention provides an electrolyte comprising a salt in accordance with the above Formula (i) or Formula (ii). The electrolyte may comprise the salt as an additive to a conventional electrolyte, or the salt may be used in a pure solution to form, with an appropriate solvent, an electrolyte by itself.
In a fourth aspect, the present invention provides a cell or battery with an electrolyte comprising a salt in accordance with the above Formula (i) or Formula (ii). The salts of the present invention do not suffer from some of the same disadvantages observed with the use of lithium salts in electrochemical cells or batteries.
When using the salt of the present invention in an electrolyte in calcium-ion cell or battery, the salt of the present invention may be useful in terms of reducing or limiting the corrosion of cell components.
In order that the present invention may be more readily understood, an embodiment of the invention will now be described, by way of example, with reference to the accompanying Figures, in which:
Figure 1 is an X-ray crystal structure of a salt crystal of the present invention selected from bulk solution;
Figure 2 is an X-ray crystal structure of another salt crystal falling outside the scope of the present invention;
Figure 3 is a XH NMR spectrum of a salt of the present invention; Figure 4 is a 19F NMR spectrum of a salt of the present invention; and Figure 5 is a 31P NMR spectrum of a salt of the present invention. The present invention will now be illustrated with reference to the following examples. Example 1 - Synthesis of (Cacl5-crown-5)(PF6)2
In a Schlenk flask, Ca (>95% purchased from Sigma Aldrich) was suspended in freshly distilled CH3CN along with 15-crown-5 (Sigma Aldrich) and stirred at room temperature under a nitrogen atmosphere. In a separate Schlenk flask, NOPF6 (purchased from ACROS Organics) was dissolved in freshly distilled CH3CN under a nitrogen atmosphere. The NOPF6 solution was then added slowly to the Ca granules using a dry syringe. The reaction mixture was stirred at room temperature for ca. 3 days. The off-white solution was then filtered through a cannula using a glass fibre filter and dried in vacuo. The resulting solid was dissolved in a minimum amount of dry CH3CN, layered with dry Et^O, and left undisturbed for several days during which colourless crystals formed. The supernatant was then decanted to isolate the colourless crystals of (Cacl5- crown-5)(PF6)2 in 46% yield.
CH3CN
Ca + 2 NOPF6 + 15-crown-5 *~ (15-crown-5)Ca(PF6)2 + 2 NO(g) room temperature
Example 2 - Characterization of (Cacl5-crown-5)(PF6)2
A single crystal obtained from the diffusion of Et^O in to a CH3CN solution of a compound of the general formula (Cacl5-crown-5)(PF6)2 as shown in Figure 1 (specifically [Cac(15-crown- 5)(CH3CN)3]2+ [Cac(l 5-crown-5)2]2+ (PF6 )4). X-ray analysis was carried out on data collected with a Bruker D8 Quest CCD diffractometer and confirmed the complex to be the desired salt (Figure 1). Bulk purity of the (Cacl5-crown-5)(PF6)2 salt crystal was confirmed by elemental analysis (C, H, and N). Elemental microanalytical data were obtained from the University of Cambridge, Department of Chemistry microanalytical service. Analysis calculated for C64Hi32Ca4F48N4024P8 [(Cac 15-crown-5)4(PF6)8(CH3CN)2 · (2 CH3CN, 4 Et20)]: C, 28.9; H, 5.0; N, 2.1; found: C, 28.5; H, 4.9; N, 2.3.
Figure 2 shows the X-ray crystal stuture of another crystal obtained from the diffusion of Et20 in to a CH3CN solution. X-ray analysis was carried out on data collected with a Bruker D8 Quest CCD diffractometer and confirmed the complex to be an undesired salt (Figure 2). The structure relates to [(Cac l5-crown- 5)4(SiF6)2(CH3CN)2]4+(PF6)4, where the two brid ging ions are SiFg . The elemental analysis (C, H, and N) of this crystal was obtained using elemental microanalytical data obtained from the University of Cambridge, Department of Chemistry microanalytical service. Analysis calculated for C36H69Ca2F24N30i5P4: C, 29.95; H, 4.82; N, 2.91 ; found: C, 29.81 ; H, 4.83; N, 2.48]
The ¾ 13C, 19F and 31P NMR spectra of the bulk white crystalline powder of (Cac l5-crown- 5)(PF6)2 are shown in Figures 3 to 5, respectively. Notably, the 19F and 31P NMR spectra exhibited a doublet and heptet, respectively, characteristic of the PF6 anion. NMR spectra were recorded at 298.0 K on a Bruker 500 MHz AVIII HD Smart Probe Spectrometer (l at 500 MHz, 31P 202 MHz, 19F 471 MHz) or a Bruker 400 MHz AVIII HD Smart Probe spectrometer (*H at 400 MHz, 31P 162 MHz, 19F 376 MHz) unless otherwise specified. Chemical shifts (δ, ppm) are given relative to residual solvent signals for XH, to external 85% H3PO4 for 31P and to CCI3F for 19F.

Claims

Claims
1. A salt of the general formula:
Ca(L)x(PF6)2
(i)
wherein x represents a number between 0 and 6; and
when x is not equal to 0, each L represents a ligand selected from one of the following compounds:
an ether or aza macrocyclic;
a halomethane or
a nitrile of the general formula R-C≡N.
2. The salt according to Claim 1, wherein when x is at least equal to 1, and L represents a ligand selected from one only of the following compounds:
an ether or aza macrocyclic;
a halomethane or
a nitrile of the general formula R-C≡N.
3. The salt according to Claim 1 or Claim 2, wherein ligand L is a cyclic crown ether selected from one of the following: [12]-crown-4, [15]-crown-5, [18]-crown-6, [24]-crown-8.
4. The salt according to Claim 1 or Claim 2, wherein ligand L is an aza-crown selected from one of the following: cyclen or cyclam.
5. The salt according to Claim 1 or Claim 2, wherein ligand L is a nitrile and R represents an organic group independently selected from the following: methyl, ethyl, propyl, butyl, 'butyl, pentyl, ethylene, propylene, butylene, pentylene, toluene, naphthalene, or phenyl.
6. The salt according to Claim 5, wherein R is the same for each nitrile ligand represented by L.
7. The salt according to Claim 5 or 6, wherein each ligand L is acetonitrile.
8. The salt according to Claim 1 or Claim 2, wherein the halomethane is dichloromethane.
9. The salt according to Claim 1, wherein a crystal formed by layering dry ether onto a concentrated CH3CN solution comprising the salt has the general formula al (Cacl5-crown-
10. A method of making a salt of the general formula:
Ca(Ly)x(PF6)2
(ii)
wherein x represent a number between 0 and 6,
when x is not equal to 0, Ly represents a ligand independently selected from any one of the following compounds:
an ether or aza macrocyclic;
a halomethane or
a nitrile of the general formula R-C≡N; and
Ly comprises a mixture of compounds Li and L2; the method comprising:
providing Ca metal,
washing and activating the Ca metal in a first dry solution comprising a first compound (Li),
treating the solution of activated Ca metal and first compound Li with NOPF6 in a second dry solution comprising a second compound (L2),
removing the residual solvent, and
recrystallizing the remaining solid to form the salt of Formula (ii).
11. The method according to Claim 7, wherein x is greater than 1, and Ly represents a ligand selected from one only of the following compounds:
an ether or aza macrocyclic;
a halomethane or
a nitrile of the general formula R-C≡N.
12. The method according to Claim 10 or Claim 11, wherein x is equal to 6, Li and L2 are each nitriles, and for Li and L2 R independently represents an organic group selected from the following: methyl, ethyl, propyl, butyl, lbutyl, pentyl, ethylene, propylene, butylene, pentylene, toluene, naphthalene, or phenyl.
13. The method in accordance with Claim 12, wherein Li and L2 are the same nitrile.
14. The method in accordance with any one of Claims 12 or Claim 13, wherein Li and L2 are both acetonitrile.
15. The method according to Claim 10 or Claim 11, wherein Ly is a cyclic crown ether selected from one of the following: [12]-crown-4, [15]-crown-5, [18]-crown-6, [24]-crown-8.
16. The method according to Claim 10 or Claim 11, wherein ligand Ly is an aza-crown selected from one of the following: cyclen or cyclam.
17. The method according to Claim 10 or Claim 11, wherein the halomethane is dichloromethane.
18. The method according to Claim 10, wherein a crystal formed by layering dry ether onto a concentrated CH3CN solution comprising the salt has the general formula (Cac l5-crown-
19. An electrolyte comprising a salt in accordance with any one of Claims 1 to 9, or comprising a salt made in accordance with the method as defined in any one of Claims 10 to 18.
20. A cell or battery comprising an electrolyte in accordance with Claim 19.
21. The cell or battery according to Claim 20, wherein the cell or battery is a calcium cell or battery or a calcium-ion cell or battery.
EP18714016.5A 2017-03-14 2018-03-13 Calcium salts Withdrawn EP3596092A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB1704038.7A GB2560534B (en) 2017-03-14 2017-03-14 Calcium salts
PCT/GB2018/050636 WO2018167477A1 (en) 2017-03-14 2018-03-13 Calcium salts

Publications (1)

Publication Number Publication Date
EP3596092A1 true EP3596092A1 (en) 2020-01-22

Family

ID=58605345

Family Applications (1)

Application Number Title Priority Date Filing Date
EP18714016.5A Withdrawn EP3596092A1 (en) 2017-03-14 2018-03-13 Calcium salts

Country Status (4)

Country Link
EP (1) EP3596092A1 (en)
CN (1) CN110446717B (en)
GB (1) GB2560534B (en)
WO (1) WO2018167477A1 (en)

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3380803A (en) * 1966-02-03 1968-04-30 Olin Mathieson Process for manufacture of alkali metal and alkaline earth metal hexafluorophosphates
JP3384625B2 (en) * 1994-08-25 2003-03-10 三洋電機株式会社 Non-aqueous electrolyte battery
JP2000149988A (en) * 1998-09-10 2000-05-30 Sanyo Electric Co Ltd Nonaqueous electrolyte secondary battery
JP3737729B2 (en) * 2001-09-26 2006-01-25 株式会社東芝 Non-aqueous electrolyte battery and non-aqueous electrolyte
WO2016050329A1 (en) * 2014-10-02 2016-04-07 Toyota Motor Europe Nv/Sa Electrolytes for calcium-based secondary cell and calcium-based secondary cell comprising the same

Also Published As

Publication number Publication date
CN110446717B (en) 2022-09-27
GB201704038D0 (en) 2017-04-26
GB2560534B (en) 2019-12-04
WO2018167477A1 (en) 2018-09-20
GB2560534A (en) 2018-09-19
CN110446717A (en) 2019-11-12

Similar Documents

Publication Publication Date Title
EP3355401B1 (en) Electrolyte for lithium-sulfur battery, and lithium-sulfur battery comprising same
KR100361273B1 (en) Electrolyte for electrochemical device
EP3262668B1 (en) Use of certain polymers as a charge store
WO2011137158A1 (en) Electrochemical device with a magnesium anode and a stable, safe electrolyte compatible with sulfur
US11133529B2 (en) Fluorinated acrylates as additives for Li-ion battery electrolytes
KR102617501B1 (en) Electrolyte composition, secondary battery, and method of using the secondary battery
JP2002110235A (en) Electrolyte for electrochemical device and battery using the same
CN108475823B (en) Non-aqueous electrolyte for lithium ion batteries comprising asymmetric borate salts
EP3391454A1 (en) Silane functionalized ionic liquids
EP3262094B1 (en) Use of certain polymers as charge storage
JP2012216419A (en) Electricity storage device
KR20130054367A (en) Method for producing a lithium hexafluorophosphate concentrated liquid
KR102612816B1 (en) Manufacturing method for lithium bisoxalatoborate with high-purity and Non-aqueous electrolyte for secondary battery
KR20200047688A (en) Magnesium salt
US20190296395A1 (en) Cyclic dinitrile compounds as additives for electrolyte
KR20160145055A (en) Use of reactive ionic liquids as additives for electrolytes in secondary lithium ion batteries
US20170058062A1 (en) Use of particular polymers as charge storage means
KR20200044121A (en) Magnesium salt
US20180233781A1 (en) Chelating ionic liquids for magnesium battery electrolytes and systems
EP2824751B1 (en) Bisamide-based electrolyte for magnesium battery
KR101435486B1 (en) Method for producing electrolyte solution for lithium ion battery
EP3596092A1 (en) Calcium salts
JP6293804B2 (en) Electrolyte solution containing magnesium salt and method for producing magnesium salt
EP3604276A1 (en) New components for electrolyte compositions
EP3416971B1 (en) Magnesium salts

Legal Events

Date Code Title Description
STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: UNKNOWN

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE INTERNATIONAL PUBLICATION HAS BEEN MADE

PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: REQUEST FOR EXAMINATION WAS MADE

17P Request for examination filed

Effective date: 20190821

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

AX Request for extension of the european patent

Extension state: BA ME

DAV Request for validation of the european patent (deleted)
DAX Request for extension of the european patent (deleted)
STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: EXAMINATION IS IN PROGRESS

17Q First examination report despatched

Effective date: 20201015

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 20210226