electrolyte, for an electrochemical battery cell, containing sulfur dioxide and a conductive salt; e

专利摘要:
ELECTROLYTE, FOR AN ELECTROCHEMICAL BATTERY CELL, CONTAINING SULFUR DIOXIDE AND A CONDUCTING SALT; ELECTROCHEMICAL BATTERY CELL; AND PROCESS FOR THE PRODUCTION OF AN ELECTROLYTE FOR AN ELECTROCHEMICAL BATTERY CELL Electrolyte for an electrochemical battery cell containing sulfur dioxide and a conducting salt. Improved characteristics of a cell filled with the electrolyte are obtained, as the molar concentration of hydroxy groups in the electrolyte is at most 50 mmol per liter and the molar concentration of chlorosulfonate groups in the electrolyte is at most 350 mmol per liter.
公开号:BR112015018315B1
申请号:R112015018315-8
申请日:2013-02-07
公开日:2021-07-06
发明作者:Laurent Zinck；Christian Pszolla；Claus Dambach
申请人:Innolith Assets Ag；
IPC主号:

专利说明:

[001] The invention relates to an electrolyte for an electrochemical battery cell. The electrolyte contains sulfur dioxide and a conductive salt. The invention also relates to a process for manufacturing the electrolyte and a battery cell containing the electrolyte.
[002] Rechargeable battery cells are of great importance in many technical fields. The development goals are, in particular, a high energy density (loading capacity per unit of weight and volume), a high charge and discharge current (low internal resistance), a long service life with a large number of cycles. loading and unloading, very good operational safety and the lowest possible costs.
[003] Electrolyte is an important functional element of all battery cells. It contains a conductive salt and is in contact with the positive and negative electrodes of the battery cell. At least one ion of the conducting salt (anion or cation) has such mobility in the electrolyte that the charge transport between the electrodes, which is necessary for the cell to function, can occur by conducting ions.
[004] According to the invention an electrolyte based on SO2 is used. In the context of the invention, this term designates an electrolyte containing sulfur dioxide not only in low concentration as an additive, but in which SO2, at least to some extent, allows the mobility of the conductive salt ions contained in the electrolyte, thus ensuring the cargo transport. The electrolyte preferably contains at least 20 percent by weight ("w%") of SO2, with values of 35% wt being even more preferred. of SO2, 45 % w. of SO2 and 55% w. of SO2, in relation to the total amount of electrolyte contained in the cell, in that order. The electrolyte can also contain up to 95% p. of SO2, maximum values of 85% w. and 75% w. [obvious error in German text: "75% p., and 85% p."] being preferred in that order.
[005] The electrolyte is preferably used in an alkali metal cell in which the active metal is an alkali metal. However, the active metal can also be an alkaline earth metal or a metal from the second subgroup of the periodic table. The term active metal designates the metal whose ions migrate to the negative or positive electrode, within the electrolyte, during the charge or discharge of the cell and which participate, there, in electrochemical processes that directly or indirectly lead to the transfer of electrons into or to outside the external circuit. The active metal is preferably lithium, sodium, calcium, zinc or aluminium, lithium being particularly preferred. Lithium cells with an SO2-based electrolyte are referred to as Li-SO2 cells. By way of example (but without limiting generality) reference will be made below to lithium as the active metal of the negative electrode.
[006] In the case of an alkali metal cell, preferably, a tetrahalo aluminate is used as the conducting salt, particularly preferably an alkali metal tetrachloro aluminate such as LiAlCl4. Other preferred conductive salts are aluminates, halides, oxalates, borates, phosphates, arsenates and gallates of an alkali metal, in particular lithium.
[007] For many years there have been discussions about SO2-based electrolytes for lithium cells. In
[008] D1 "Handbook of Batteries", David Linden (Editor), 2nd edition, McGraw-Hill, 1994
[009] the high ionic conductivity of an inorganic electrolyte based on SO2 is emphasized. It is claimed that this electrolyte is also advantageous over other electrical data. Furthermore, it is also stated that systems with an SO2-based electrolyte have been under investigation for a long period of time and are of interest for special applications, but that the additional commercial applicability is restricted, in particular because the electrolyte is highly corrosive.
[010] An advantage of the SO2-based electrolyte is that - in contrast to the organic electrolytes of lithium-ion cells common in practice - it does not burn. Known safety hazards of lithium-ion cells are mainly caused by their organic electrolytes. If a lithium-ion cell catches fire or even explodes, the organic solvent in the electrolyte forms the combustible material. An electrolyte according to the invention is preferably essentially free of organic materials, whereby "essentially free" is to be interpreted in such a way that the amount of any organic materials present is so small that it does not pose any safety risk.
[011] On this basis, the present invention solves the technical problem of providing an SO2-based electrolyte that - while maintaining the advantageous characteristics of such electrolytes - leads to better electrical characteristics of an electrochemical battery cell filled with the electrolyte.
[012] The problem is solved by an electrolyte according to claim 1. In the electrolyte, the content of compounds containing a hydroxy group (OH-) is so low that the molar concentration of hydroxy groups in the electrolyte is at most , 50 mmol (millimols) per liter. At the same time, the content of compounds containing a chlorosulfonate group (SO3Cl-) is so low that the molar concentration of chlorosulfonate groups in the electrolyte is at most 350 mmol per liter.
[013] An SO2 based electrolyte is generally produced by mixing the Lewis acid component and the Lewis base component of the conductive salt together and allowing these to react with the gaseous SO2 which is flowed over or through mixing. In an exothermic reaction, a Lewis acid/Lewis base adduct is formed, which is dissolved in SO2, for example: LiCl + AlCl3 LiAlCl4. When the conducting salt dissolves in SO2, its ions become mobile, eg Li+ and AlCl4-.
[014] This process is described in the literature, for example, in
[015] D2 US Patent 4,891,281 and
[016] D3 D.L. Foster et al: "New Highly Conductive Inorganic Electrolytes", J. Electrochem. Soc., 1988, 2682 - 2686.
[017] A problem that has been discussed for a long time is that, during the production of the electrolyte, traces of water are dragged in which the conductive salt reacts to produce hydrolysis products, said hydrolysis products containing hydroxide groups. The following reaction occurs, for example:
[018]

[019] The following publications address this issue:
[020] D4 US Patent 4,925,753
[021] In the cell described here, SO2 serves both as a conductive salt solvent and a liquid cathode. The document describes how moisture and hydrolysis products are drawn into the electrolyte by the starting materials and cause increased corrosion of cell components, in particular the lithium anode. To prevent moisture from being drawn in, one Lewis component (alkali metal salt) is dried at 200 degrees Celsius for 16 hours and the other Lewis component (aluminum chloride) is newly sublimated. Furthermore, the aluminum concentration is increased (eg by increasing the LiAlCl4 concentration) in order to achieve a higher starting capacity during cell operation. Additionally, a calcium salt of the same anion is added, which serves as an "anti-freeze agent", compensating for the increase in the freezing temperature of the electrolyte, caused by the increase in the concentration of LiAlCl4.
[022] D5 US Patent 5,145,755
[023] This document describes the study of an electrolyte produced according to the D4 document, through IR spectral analysis. This shows a strong and wide absorption band in the area of the OH oscillation. The cleaning effect of the process described in document D4 is therefore insufficient. A different method for removing hydrolysis products from the electrolyte solution is described in document D5. Here, the starting salts (Lewis acid and Lewis base) are mixed and heated with sulfuryl chloride under reflux at 90°C. The salt mixture is then melted at 120°C to 150°C to remove the sulfuryl chloride. By feeding SO2 gas to the salt mixture, an electrolyte is produced which is considered to be essentially free of hydrolysis products.
[024] D6 R.R. Hill and R.J. Dore: "Dehydroxylation of LiAlCl4 xSO2 Electrolytes Using Chlorine", J. Electrochem. Soc., 1996, 3585 - 3590
[025] This publication describes, as an introduction, previous attempts at dehydroxylation of SO2-based electrolytes. It is explained that a significant disadvantage of this type of electrolyte is that it normally contains hydroxide contamination and that previous attempts to eliminate this contamination have been insufficient. Based on the fact that the necessary dehydroxylation cannot be achieved through heating, the authors conclude that chemical treatment is necessary. Regarding dehydroxylation through sulfuryl chloride, described in D5, they criticize the fact that recontamination with water can occur when the electrolyte is produced using clean salt. For this reason, they say that dehydroxylation of the LiAlCl4 xSO2 electrolyte should be preferred. To this end, the document compares two processes in which the electrolyte is treated with sulfuryl chloride (SO2Cl2) and chlorine gas (Cl2), respectively. Both processes are said to allow sufficient dehydroxylation. The chlorine gas method is seen as the preferred method. As shown in the IR spectra in the document, in both processes chlorosulfonate groups are produced which replace the hydroxy groups. The electrochemical activity of the chlorosulfonate groups is investigated by observing the intensity of the corresponding infrared bands during extensive cell discharge. It is said that the intensity of the bands does not decrease and that, consequently, the chlorosulfonate groups do not participate in cell reactions.
[026] In the context of the present invention, it has been established that (SO3Cl)- which is inevitably produced in known processes for the removal of compounds containing hydroxides, significantly impairs the functioning of the cell and that a considerable improvement, particularly in With regard to the cell's charging capacity and its ease of use for a large number of charge and discharge cycles, it is achieved if not only the molar concentration (also referred to as the number of moles) of hydroxide groups in the electrolyte is less than 50 mmol per liter, but at the same time the molar concentration of chlorosulfonate groups in the electrolyte does not exceed a maximum value of 350 mmol per liter. Particularly good results are achieved if the molar concentration of hydroxy groups in the electrolyte is at most 45 mmol per liter, preferably at most 25 mmol per liter, even more preferably at most 15 mmol per liter and particularly preferably of at most 5 mmol per litre. With regard to the molar concentration of chlorosulfonate groups in the electrolyte, it is particularly advantageous if its maximum value does not exceed 250 mmol per liter, preferably 200 mmol per liter and particularly preferably 150 mmol per liter.
[027] As already described, the hydroxide groups can be produced by traces of water being dragged to the starting materials for the production of the electrolyte or to the electrolyte itself. According to reaction equation (A), water can react with the electrolyte to produce the compound containing hydroxide AlCl3OH-. However, other compounds containing hydroxide can also be produced. All hydroxide-containing compounds can be detected using infrared spectroscopy, by oscillating OH at a wavenumber of about 3350 cm-1. In contrast to infrared spectroscopy, the well-known Karl Fischer method for the analysis of water traces is not suitable for the determination of compounds containing hydroxide in the electrolyte. In addition to hydroxide-containing compounds, such as AlCl3OH-, the Karl Fischer method also detects oxide-containing compounds from the electrolyte, such as AlOCl. A high Karl Fischer value does not therefore correspond to a high concentration of hydroxide-containing compounds.
[028] Compounds containing chlorosulfonate groups are produced, for example, by the reaction of chlorine with compounds containing hydroxide of the electrolyte solution, according to the equation
[029]
HCl
[030] Compounds containing chlorosulfonate groups can be detected in the electrolyte by infrared spectroscopy. Three bands at the wavenumbers of approximately 665 cm-1, 1070 cm-1 and 1215 cm-1 are characteristic of the presence of compounds with chlorosulfonate groups.
[031] The preferred percentages by weight of SO2 in the total amount of electrolyte contained in the cell have already been mentioned. The percentage by weight of the conductive salt in the electrolyte should preferably be less than 70%, with values less than 60, 50, 40, 30, 20 and 10% by weight being more preferred, in that order.
[032] The electrolyte should preferably comprise mainly the SO2 and the conductive salt. The percentage by weight of SO2 and conductive salt in relation to the total weight of the electrolyte in the cell should preferably be greater than 50% w., values of more than 60, 70, 80, 85, 90, 95 and 99 being preferred %p., in that order.
[033] Several different salts can be dissolved in the electrolyte, such that at least one of its ions is mobile in the electrolyte and contributes, by ion conduction, to the charge transport necessary for the cell operation, so let the salt act as a conductive salt. Preferably, the fraction of salts whose cation is the cation of the active metal predominates. With respect to the number of moles of all salts dissolved in the electrolyte, the molar fraction of salts dissolved in the electrolyte with a cation other than the active metal cation should be at most 30 mol%, with values of at most being preferred , 20 mol %, 10 mol %, 5 mol % and 1 mol %, in that order.
[034] With regard to the molar ratio of conductive salt and sulfur dioxide, it is preferable that the electrolyte contains at least 1 mol of SO2 per mol of conductive salt, with values of 2, 3, 4 and 6 mols being even more preferred of SO2 per mole of conductive salt, in that order. Very high molar fractions of SO2 are possible. The preferred upper limit can be specified as 50 mol SO2 per mol conductive salt, and even more preferred upper limits of 25 and 10 mol SO2 per mol conductive salt, in that order.
[035] As explained above, the electrolyte according to the invention is preferably essentially free of organic materials. However, this does not exclude some embodiments of the invention also containing organic materials in the electrolyte, such as one or a plurality of organic co-solvents. In such a configuration, however, the total amount of organic material in the electrolyte should in any case be less than 50% w., with values of less than 40, 30, 20, 15, 10, 5, 1 and more preferred. 0.5% w., in relation to the total weight of the electrolyte, in that order. According to another preferred embodiment, the organic material has a flash point of less than 200°C, with values of 150, 100, 50, 25 and 10°C, in that order, being even more preferred.
[036] According to another preferred configuration, the electrolyte contains two or more organic materials, the organic materials having an average flash point (calculated from the weight ratio) less than 200 °C, with values of 150 being more preferred, 100, 50, 25 and 10°C, in that order.
[037] A suitable process for the production of an electrolyte according to the invention is characterized by the following steps:
[038] - a Lewis acid, a Lewis base and aluminum are mixed in solid state.
[039] - the mixture is kept at a minimum temperature for a minimum period of 6 hours, the minimum temperature being higher than the melting point of the mixture and at least 200 °C. An adduct of Lewis acid and Lewis base is formed.
[040] The minimum temperature is preferably 250 °C, values of 300 °C, 350 °C, 400 °C, 450 °C and 500 °C being particularly preferred, in that order. The minimum period is preferably 12 hours, with values of 18, 24, 48 and 72 being particularly preferred, in that order.
[041] The fraction of aluminum in the starting mixture must be at least 40 mmol of aluminum per mole of Lewis acid, with values of 200 and 400 mmols per mole of Lewis acid being even more preferred, in that order.
[042] The Lewis acid is preferably AlCl3. The Lewis base is preferably a conducting salt chloride, therefore LiCl in the case of a lithium cell.
[043] The starting substances are preferably used in particulate form and well mixed before heating. The increase in temperature must occur slowly, mainly to avoid a rapid increase in pressure. In order to compensate for a possible increase in gas pressure, the reaction vessel must be opened at least at the beginning of the heating process, the unwanted entry of external gases being favorably prevented by the application of a vacuum or the use of a liquid seal similar to a wash bottle. It may be favorable to remove solid contamination, in particular aluminum, by filtration (eg using a fiberglass filter cloth) at the end of the process. Filtration must be carried out at a temperature at which the molten mass is liquid enough to pass through the filter. On the other hand, the temperature must be low enough to avoid damage to the filter and any contamination of the melt caused by it. In practice, a temperature of 250 °C proved to be adequate.
[044] The invention is described in more detail, hereinafter, with reference to the figures, exemplary configurations and experimental results. The features described can be used individually or in combination to create preferred embodiments of the invention. In the figures:
[045] Figure 1 shows a cross-sectional view of a battery cell according to the invention;
[046] Figure 2 shows the FTIR (infrared radiation by Fourier transform - transmission) spectra of calibration of electrolyte solutions with five different molar concentrations of hydroxide groups;
[047] Figure 3 shows the FTIR (transmission) spectra of electrolytes with different molar concentrations of hydroxide groups;
[048] Figure 4 shows a graphical representation of the dependence of the number of cycles in which a discharge capacity of 66.5% of the nominal capacity is reached, for cells that contain different molar concentrations of hydroxide groups;
[049] Figure 5 graphic of the capacity consumed irreversibly for the formation of the covering layer of the electrodes, for cells with different molar concentrations of hydroxide groups;
[050] Figure 6 shows a graphical representation of the discharge capacity as a function of the number of cycles of two cells with different molar concentrations of hydroxide groups in the electrolyte;
[051] Figure 7 shows a FTIR (ATR) spectrum of two electrolytes that contain different molar concentrations of chlorosulfonate groups;
[052] Figure 8 shows a graphical representation of the relationship of the cover layer capacity and the discharge capacity of cells with different molar concentrations of chlorosulfonate groups in their electrolytes.
[053] The housing 1 of the rechargeable battery cell 2 shown in FIG. 1 includes an electrode array comprising a plurality (three in the case shown) of positive electrodes 4 and a plurality (four in the case illustrated) of negative electrodes 5. The electrodes 4, 5 are connected, in the usual way, with the terminals of corresponding contacts 9, 10 of the battery, by means of electrode pins 6, 7. The cell is filled with an electrolyte based on SO2 8, in such a way that the electrolyte preferably penetrates completely into all pores, in particular , inside electrodes 4, 5. The electrolyte can be in liquid or gel form.
[054] As is common, the electrodes 4, 5 have a flat shape, that is, they have the form of layers having a thickness that is small in relation to its extension in the other two dimensions. The electrodes 4, 5 usually comprise a current collecting element which is made of metal and serves to provide the required electronically conductive connection of the active material of the respective electrode. The current collector element is in contact with the active material involved in the electrode reaction of the respective electrode. The electrodes are separated from each other by separators 11 in each case. Housing 1 of the prismatic cell shown is essentially cuboid, the walls and electrodes shown in cross section in Fig. 1 extending perpendicular to the plane of the drawing and being essentially straight and flat. However, the cell according to the invention can also be designed as a spiral-wound cell.
[055] The negative electrodes 5 are preferably insertion electrodes, that is, they comprise an electrode material into which the active metal ions are inserted during cell charging and from which they are extracted during the discharge of the cell. Preferably, the negative electrodes contain carbon.
[056] The active mass of the positive electrode is a component of the cell that changes its state of charge as a consequence of the redox reaction that occurs in the positive electrode. In cells according to the invention, the active mass of the positive electrode is preferably an intercalating compound into which the active metal can be inserted. Metal compounds are especially suitable compounds (eg oxides, halides, phosphates, sulfides, chalcogenides, selenides) of an especially suitable transition metal, in particular an element of atomic numbers 22 to 28, especially cobalt, nickel, manganese or iron , including mixed oxides and other mixed compounds of metals. Lithium iron phosphate is particularly preferred. When such a cell is discharged, active metal ions are inserted into the positive active mass. For reasons of charge neutrality, this leads to an electrode reaction from the positive active mass on the electrode, where an electron is transferred from a current-collecting element of the electrode to the positive active mass. The reverse process takes place during charging: the active metal (eg lithium) is extracted as an ion from the positive active mass and an electron is transferred from the latter to the current-collecting element of the positive electrode.
[057] Figures 2 to 8 are based on the experimental testing of the invention.
[058] Figure 2 shows the FTIR spectra of calibration solutions with different molar concentrations of hydroxide groups. Absorbance A is shown as a function of the wavenumber k.
[059] Suitable calibration solutions can be produced, for example, by adding a defined amount of lithium chloride monohydrate to an electrolyte that does not present any OH absorption band, that is, does not contain any hydroxy group. The addition of 0.0604 g of lithium chloride monohydrate increases the water content and therefore also the hydroxy group content of the calibration electrolyte by 1 mmol.
[060] Calibration electrolytes with different molar concentrations of hydroxide groups were analyzed by infrared spectroscopy in the range of the absorption band of OH- (3300 cm-1). Figure 2 shows the spectra for the five molar concentrations of hydroxy groups indicated in the graph.
[061] Figure 3 shows a representation corresponding to Figure 2 in which, in addition to the calibration curves for molar concentrations of zero hydroxide (dotted) and 76 mmol per liter (solid line), the FTIR spectrum of an electrolyte is shown (dashed line) which was produced according to the instructions in the D3 document mentioned above. The spectrum shows that the electrolyte produced according to this state of the art contained approximately 94 mmol per liter (corresponding to approx. 1000 ppm) of hydroxy groups. Document D6 cited above also states that a dirty electrolyte contains an amount of hydroxide corresponding to this molar concentration.
[062] Hydroxide-containing compounds have a detrimental effect on the electrochemical properties of a battery cell. The QD discharge capacity specifies the charge capacity that can be drawn from a battery cell during discharge. Generally, QD decreases from cycle to cycle during loading and unloading. The smaller this decrease, the longer the battery life.
[063] Figure 4 shows the influence of the molar concentration of hydroxy groups on the decrease in capacity and, therefore, on the battery cell lifetime. The graph is based on an experiment where battery cells with two negative carbon electrodes, a SO2-based electrolyte with LiAlCl4 as the conducting salt and a positive lithium iron phosphate electrode, are charged and discharged over several hundred cycles. The nominal capacity of the cell was 100 mAh. Charging of the cells took place at 1 C, corresponding to a current of 100 mA up to an end-of-charge voltage of 3.6 V and a drop in charge current of 40 mA. After this, the cells were discharged with the same current, until a potential of 2.5 V was reached. There was a 10-minute pause in each case, between charging and discharging.
[064] Figure 4 shows the number of load and unload cycles performed with the test cells, until a defined minimum capacity is reached (here of 66.5% of the nominal capacity). The hydroxide-free cell, which is represented by the left column, reached this value only after 500 cycles. In contrast, the other cells, with a hydroxide content of 16 [obvious error in German text: "19"], 40 and 50 mmol/l, achieved a much lower number of cycles, the cell with a hydroxide content of 50 mmol/l reaching approximately only 300 cycles. Assuming, for example, that a battery cell is charged and discharged once a day and is to be used up to the specified discharge capacity, this means that the hydroxide-free cell has a useful life of 1 year and 7 months, when whereas the cell with a hydroxide content of 50 mmol/l can only be used for a period of 10 months.
[065] As already explained, the hydroxide groups contained in the electrolyte of an electrochemical cell lead to a deterioration of the electrical data of said cell, as the amount of charge irreversibly consumed in the initial charge cycles, for the formation of a layer electrode coverage ("capacity of the covering layer" QC) increases as a function of the molar concentration of hydroxide ions. The capacity of the cover layer QC can be determined, for example, by comparing the loading and unloading capacities of the cell in the first cycle. Figure 5 shows the results of these experiments. The capacity of the QC overlay layer (as a percentage of the theoretical charge capacity of the negative electrode) is shown as a function of the molar concentration M of hydroxide ions contained in four different electrolytes. It can be seen that the covering layer capacity is greater for a cell with 50 mmol/l than for a cell whose electrolyte does not contain any hydroxide ions. The useful discharge capacity of cells that do not contain any hydroxide is correspondingly greater.
[066] The effect is substantial, as all subsequent charge and discharge cycles for a hydroxide-containing cell start at a correspondingly lower level than in hydroxide-free cells. Figure 6 shows the QD discharge capacity as a percentage of the nominal capacity as a function of the number of charge and discharge cycles, the continuous curve showing the results with a hydroxide-free electrolyte and the dashed curve showing the results for an electrolyte with a molar concentration of hydroxy groups of 50 mmol/l.
[067] As described above, in the past different methods have been tested to remove hydroxide-containing contamination from the electrolyte and thus eliminate the associated disadvantages. It has been established that the desired cleaning effect cannot be achieved by using dry starting substances and/or heating the electrolyte. For this reason, chemical methods using chlorine or chlorine-containing substances have been proposed (cf. D5 and D6). However, it has been established in the context of the invention that the formation of chlorosulfonate groups in the electrolyte, associated with such methods, causes additional problems.
[068] Figure 7 shows the FTIR spectrum (ATR), namely the absorbance A as a function of the wave number k, for two electrolyte solutions that contained (dashed line) no sulfonate group and 290 mmol/l ( solid line) of sulfonate groups, respectively. Three bands can be clearly seen at wavenumbers 665 cm-1, 1070 cm-1 and 1215 cm-1, which may occur due to the presence of compounds containing chlorosulfonate groups.
[069] Figure 8 shows the capacity of the QC overlay layer for cells whose electrolyte contained three different molar concentrations of chlorosulfonate groups. These measurements were performed as half-cell experiments, in a three-electrode system (working electrode: carbon (graphite); counter-electrode: lithium; reference electrode for measuring potential without current: lithium). The electrodes were placed in a glass E-cell and this was filled, in each case, with the electrolyte solution to be analyzed. The left column shows the example of a cell with an electrolyte according to the invention, which was essentially free of hydroxy groups, but which was at the same time essentially free of chlorosulfonate groups. Cover layer capacity is only 17% here. The other two columns show the results for cells with 73 mmol/l and 291 mmol/l of chlorosulfonate groups. The greater the capacity of the covering layer, the lower the discharge capacity. This means that the percentage ratio between the QC cover layer capacity (irreversible and therefore wasted) and the QD useful discharge capacity significantly worsens due to the chlorosulfonate content.
[070] An electrolyte according to the invention can be produced, for example, through the following process:
[071] a) Drying: Lithium chloride is vacuum dried for three days at 120 °C. Aluminum particles are vacuum dried for two days at 450 °C.
[072] b) Mixture: 434 g (10.3 mol) of LiCl, 1300 g (9.7 mol) of AlCl3 and 100 g (3.4 mol) of Al are mixed well in a glass bottle with an opening that allows the gas to escape. The amounts correspond to a molar ratio of AlCl3:LiCl:Al of 1:1.06:0.35.
[073] c) Melting/heat treatment: The mixture is heat treated as follows:
[074] - two hours at 250 °C;
[075] - two hours at 350 °C;
[076] - two hours at 500 °C;
[077] - after 6 hours, the opening of the bottle is closed;
[078] - three days at 500 °C;
[079] d) Cooling/filtration: After cooling to 250 °C, the molten material is filtered through a fiberglass fabric.
[080] e) Addition of SO2: The molten mass is cooled to room temperature after one day. The bottle with molten material is evacuated. SO2 is supplied from a vessel containing the pressurized SO2 gas until the desired molar ratio of SO2 to LiAlCl4 is obtained. This can be checked by weighing. The bottle is cooled during the supply of SO2, whereby the molten mass of salt dissolves in the SO2 and a liquid electrolyte according to the invention is obtained.
[081] An adduct of Lewis base LiCl and Lewis acid AlCl3 is formed by the described process. Excess LiCl means the electrolyte contains free LiCl. This prevents the formation of free AlCl3. Generally, regardless of the example mentioned, it is advantageous for the electrolyte to contain free Lewis base in addition to the Lewis acid/Lewis base adduct. In other words, the molar ratio of the sum of the free Lewis base and Lewis base contained in the Lewis acid/Lewis base adduct to the Lewis acid contained in the Lewis acid/Lewis base adduct must be greater than that 1.

权利要求:
Claims (21)
[0001]
1. ELECTROLYTE, FOR AN ELECTROCHEMICAL BATTERY CELL, CONTAINING SULFUR DIOXIDE AND A CONDUCTING SALT, characterized by the molar concentration of hydroxide groups in the electrolyte being at most 50 mmol per liter, and the molar concentration of chlorosulfonate groups in the electrolyte being of a maximum of 350 mmol per liter.
[0002]
2. ELECTROLYTE according to claim 1, characterized in that the molar concentration of hydroxide groups in the electrolyte is at most 45 mmol per liter.
[0003]
3. ELECTROLYTE according to claim 1, characterized in that the molar concentration of chlorosulfonate groups in the electrolyte is at most 250 mmol per liter.
[0004]
4. ELECTROLYTE according to any one of claims 1 to 3, characterized in that the electrolyte contains at least 1 mol of SO2 per mol of conductive salt.
[0005]
5. ELECTROLYTE according to any one of claims 1 to 4, characterized in that the conducting salt is a Lewis acid/Lewis base adduct and the electrolyte contains free Lewis base.
[0006]
6. ELECTROLYTE according to any one of claims 1 to 5, characterized in that the conductive salt is an aluminate, halide, oxalate, borate, phosphate, arsenate or gallate of an alkali metal.
[0007]
7. ELECTROLYTE according to claim 6, characterized in that the conductive salt is a lithium aluminate tetrahalo.
[0008]
8. ELECTROLYTE according to any one of claims 1 to 7, characterized in that it contains, in relation to the number of moles of all salts dissolved in the electrolyte, at most 30% in mol of dissolved salt having a cation that differs from the cation of the active metal.
[0009]
9. ELECTROCHEMICAL BATTERY CELL containing an electrolyte, as defined in any one of claims 1 to 8, a positive electrode and a negative electrode, characterized in that the molar concentration of hydroxide groups in the electrolyte is at most 50 mmol per liter, and that the molar concentration of chlorosulfonate groups in the electrolyte is a maximum of 350 mmol per liter.
[0010]
10. BATTERY CELL according to claim 9, characterized in that the active metal is an alkali metal, an alkaline earth metal or a metal from group 12 of the periodic table or aluminum.
[0011]
11. BATTERY CELL according to claim 10, characterized in that the active metal is lithium, sodium, calcium, zinc or aluminum.
[0012]
12. BATTERY CELL, according to any one of claims 9 to 11, characterized in that the negative electrode is an insertion electrode.
[0013]
13. BATTERY CELL according to claim 12, characterized in that the negative electrode contains carbon.
[0014]
14. BATTERY CELL, according to any one of claims 9 to 13, characterized in that the positive electrode contains a metallic compound.
[0015]
15. BATTERY CELL according to claim 14, characterized in that the metal compound is a metal oxide or a metal halide or a metal phosphate, said metal being a transition metal of atomic numbers 22 to 28.
[0016]
16. BATTERY CELL according to claim 15, characterized in that the positive electrode contains an intercalation compound.
[0017]
17. BATTERY CELL, according to claim 16, characterized in that the positive electrode contains lithium iron phosphate.
[0018]
18. PROCESS FOR THE PRODUCTION OF AN ELECTROLYTE FOR AN ELECTROCHEMICAL BATTERY CELL, as defined in any one of claims 1 to 8, characterized in that a Lewis acid, a Lewis base and aluminum are mixed and the mixture is heated for a period of time minimum of 6 hours at a temperature above a minimum temperature, the minimum temperature being at least 200°C and being above the melting point of the mixture, whereby an adduct of Lewis acid and Lewis base is formed .
[0019]
19. Process according to claim 18, characterized in that the minimum temperature is 250°C.
[0020]
20. Process according to any one of claims 18 or 19, characterized in that the minimum period is 12 hours.
[0021]
21. Process according to any one of claims 18 to 20, characterized in that the mixture contains at least 40 mmol of aluminum for each mole of Lewis acid.

类似技术:

---

公开号 | 公开日 | 专利标题

---

BR112015018315B1|2021-07-06|electrolyte, for an electrochemical battery cell, containing sulfur dioxide and a conductive salt; electrochemical battery cell; and process for producing an electrolyte for an electrochemical battery cell

---

US10892487B2|2021-01-12|Rechargeable electrochemical cell

---

ES2398345T3|2013-03-15|Electrochemical battery cell

---

Novak et al.1993|Electrochemical insertion of magnesium in metal oxides and sulfides from aprotic electrolytes

---

CA1076645A|1980-04-29|Electrochemical cell with clovoborate salt in electrolyte

---

Huang et al.2018|Rechargeable aluminum–selenium batteries with high capacity

---

US6187479B1|2001-02-13|Ambient temperature, rechargeable cells with metal salt-based electrodes and a system of cell component materials for use therein

---

BRPI0718646B1|2018-12-11|rechargeable electrochemical battery cell

---

ES2871523T3|2021-10-29|Rechargeable electrochemical lithium cell with electrolytes containing sulfur dioxide

---

JP6314152B2|2018-04-18|Prevention of deterioration of solid alkali ion conductive membrane

---

JP2711545B2|1998-02-10|Non-aqueous battery

---

US8410759B2|2013-04-02|Electrolyte for an electrochemical battery cell

---

Pang et al.2020|Understanding the mechanism of byproduct formation with in operando synchrotron techniques and its effects on the electrochemical performance of VO 2 | nanoflakes in aqueous rechargeable zinc batteries

---

Yoo et al.2017|Stable Performance of Aluminum‐Metal Battery by Incorporating Lithium‐Ion Chemistry

---

Foster et al.1988|New Highly Conductive Inorganic Electrolytes: The Liquid Solvates of the Alkali and Alkaline Earth Metal Tetrachloroaluminates

---

BRPI0611450A2|2010-09-08|battery cathodes

---

Medenbach et al.2020|A sodium polysulfide battery with liquid/solid electrolyte: improving sulfur utilization using P2S5 as additive and tetramethylurea as catholyte solvent

---

Ng et al.2018|A New generation of rechargeable aluminum ion battery technology

---

BR112020018134A2|2020-12-22|SOLID IONIC CONDUCTOR FOR RECHARGEABLE ELECTROCHEMICAL BATTERY CELLS

---

JP3346181B2|2002-11-18|Non-aqueous electrolyte secondary battery

---

NANOSCALE2014|Contributions by undergraduate researcher Brianna DeRooy to impedance, short-circuit, and lithium transference number testing.

同族专利:

---

公开号 | 公开日

---

MX2015009865A|2015-10-05|

---

AU2013377470A1|2015-07-16|

---

AU2018253519A1|2018-11-15|

---

ECSP15033398A|2016-01-29|

---

EP2954588B1|2017-04-12|

---

AU2018253519B2|2019-12-05|

---

MX365048B|2019-05-16|

---

RU2015137755A|2017-03-14|

---

HK1215760A1|2016-09-09|

---

CN104969404B|2019-06-14|

---

PL2954588T3|2017-07-31|

---

US9515349B2|2016-12-06|

---

US20150207172A1|2015-07-23|

---

US20140220428A1|2014-08-07|

---

CA2898245C|2020-09-22|

---

JP6381553B2|2018-08-29|

---

KR20150115788A|2015-10-14|

---

US9023538B2|2015-05-05|

---

EP2954588A1|2015-12-16|

---

ES2625775T3|2017-07-20|

---

KR101947370B1|2019-02-13|

---

IL239696D0|2015-08-31|

---

JP2016511922A|2016-04-21|

---

SG11201506223WA|2015-09-29|

---

DK2954588T3|2017-07-24|

---

CA2898245A1|2014-08-14|

---

RU2629556C2|2017-08-30|

---

CN104969404A|2015-10-07|

---

BR112015018315A2|2017-07-18|

---

WO2014121803A1|2014-08-14|

引用文献:

---

公开号 | 申请日 | 公开日 | 申请人 | 专利标题

---

---

US3843414A|1970-03-27|1974-10-22|Accumulateurs Fixes|Method of preparing non-aqueous electrolyte free of any trace of free aluminum chloride|

---

US3892589A|1971-12-02|1975-07-01|Power Conversion Inc|Sealed battery construction|

---

US4076794A|1974-08-01|1978-02-28|Foote Mineral Company|Process for the production of high purity alkali metal tetrahaloaluminates and products produced thereby|

---

US4309490A|1976-10-08|1982-01-05|Honeywell Inc.|Long life thionyl chloride cell|

---

US4515875A|1981-12-14|1985-05-07|Duracell Inc.|Inorganic rechargeable non-aqueous cell|

---

CA1210056A|1982-08-09|1986-08-19|Han C. Kuo|Electrochemical cells having low vapor pressurecomplexed so.sub.2 electrolytes|

---

US4891281A|1982-08-09|1990-01-02|Duracell Inc.|Electrochemical cells having low vapor pressure complexed SO2 electrolytes|

---

US4513067A|1983-06-30|1985-04-23|Duracell Inc.|Inorganic non-aqueous cell|

---

US4925753A|1988-09-28|1990-05-15|Schlaikjer Carl R|Lithium/sulfur dioxide cell|

---

RU2027703C1|1991-05-08|1995-01-27|Научно-производственное объединение "Государственный институт прикладной химии"|Method of preparing of glare-cross-linking addition for electrolyte of copper sulfate plating|

---

USH1054H|1991-06-14|1992-05-05|The United States Of America As Represented By The Secretary Of The Army|Electrochemical cell that delivers high power pulses|

---

US5145755A|1991-08-29|1992-09-08|The United States Of America As Represented By The Secretary Of The Navy|Method of making tetrachloroaluminate + sulfur dioxide electrolytes in which hydrolysis products are removed|

---

EP1665447B1|2003-09-23|2017-04-12|Alevo International S.A.|Electrochemical battery cell|

---

RU2373592C1|2006-09-11|2009-11-20|Асахи Касеи Кабусики Кайся|Polymer electrolyte, method of its production and electrochemical element|

---

EP1923934A1|2006-11-14|2008-05-21|Fortu Intellectual Property AG|Rechargeable electrochemical battery|

---

EP2071658A1|2007-12-14|2009-06-17|Fortu Intellectual Property AG|Electrolyte for an electrochemical battery cell|

---

US9209458B2|2010-02-10|2015-12-08|Alevo Research Ag|Rechargeable electrochemical battery cell|

---

EP2360772A1|2010-02-12|2011-08-24|Fortu Intellectual Property AG|Rechargeable and electrochemical cell|

---

US20130040188A1|2011-08-12|2013-02-14|Fortu Intellectual Property Ag|Rechargeable electrochemical battery cell|DK2909875T3|2012-10-16|2020-08-24|Ambri Inc|ELECTROCHEMICAL ENERGY STORAGE DEVICES AND HOUSES|

---

US9312522B2|2012-10-18|2016-04-12|Ambri Inc.|Electrochemical energy storage devices|

---

US9735450B2|2012-10-18|2017-08-15|Ambri Inc.|Electrochemical energy storage devices|

---

US11211641B2|2012-10-18|2021-12-28|Ambri Inc.|Electrochemical energy storage devices|

---

US10541451B2|2012-10-18|2020-01-21|Ambri Inc.|Electrochemical energy storage devices|

---

US9520618B2|2013-02-12|2016-12-13|Ambri Inc.|Electrochemical energy storage devices|

---

US10270139B1|2013-03-14|2019-04-23|Ambri Inc.|Systems and methods for recycling electrochemical energy storage devices|

---

US9502737B2|2013-05-23|2016-11-22|Ambri Inc.|Voltage-enhanced energy storage devices|

---

KR101610014B1|2014-09-16|2016-04-11|전자부품연구원|Electrolyte solution comprising sulfur dioxide based ionic liquid electrolyte and sodium-sulfur dioxide secondary battery having the same|

---

KR101586194B1|2014-09-16|2016-01-20|전자부품연구원|Cathode materials having metal-chloride and alkali metal-chloride, and Alkali-ion rechargeable batteries containing the same|

---

DE102014226396A1|2014-12-18|2016-06-23|Bayerische Motoren Werke Aktiengesellschaft|Composite cathode and this comprehensive lithium-ion battery and method for producing the composite cathode|

---

US10181800B1|2015-03-02|2019-01-15|Ambri Inc.|Power conversion systems for energy storage devices|

---

WO2016141354A2|2015-03-05|2016-09-09|Ambri Inc.|Ceramic materials and seals for high temperature reactive material devices|

---

US9893385B1|2015-04-23|2018-02-13|Ambri Inc.|Battery management systems for energy storage devices|

---

FI128461B|2016-03-04|2020-05-29|Broadbit Batteries Oy|Rechargeable sodium cells for high energy density battery use|

---

US10804562B2|2017-12-06|2020-10-13|Tesla Motors Canada ULC|Method and system for determining concentration of electrolyte components for lithium-ion cells|

---

PL3772129T3|2019-07-31|2021-09-27|Innolith Technology AG|So2-based electrolyte for rechargeable battery cell and rechargeable battery cell comprising the same|

---

EP3771011A3|2020-12-09|2021-06-30|Innolith Technology AG|So2-based electrolyte for rechargeable battery cell and rechargeable battery cell|

法律状态:
2018-03-27| B06F| Objections, documents and/or translations needed after an examination request according [chapter 6.6 patent gazette]|

---

2018-05-15| B25A| Requested transfer of rights approved|Owner name: ALEVO INTERNATIONAL S.A. (CH) |

---

2019-05-14| B25A| Requested transfer of rights approved|Owner name: BLUEHORN SA (CH) |

---

2019-05-28| B25A| Requested transfer of rights approved|Owner name: INNOLITH ASSETS AG (CH) |

---

2019-10-22| B06U| Preliminary requirement: requests with searches performed by other patent offices: procedure suspended [chapter 6.21 patent gazette]|

---

2021-01-19| B06A| Patent application procedure suspended [chapter 6.1 patent gazette]|

---

2021-05-18| B09A| Decision: intention to grant [chapter 9.1 patent gazette]|

---

2021-07-06| B16A| Patent or certificate of addition of invention granted [chapter 16.1 patent gazette]|Free format text: PRAZO DE VALIDADE: 20 (VINTE) ANOS CONTADOS A PARTIR DE 07/02/2013, OBSERVADAS AS CONDICOES LEGAIS. |

优先权:

---

申请号 | 申请日 | 专利标题

---

PCT/EP2013/000366|WO2014121803A1|2013-02-07|2013-02-07|Electrolyte for an electrochemical battery cell and battery cell containing the electrolyte|

---