JPH0696615A - Ion conductive polymer electrolyte - Google Patents

Abstract

PURPOSE:To provide an ion conductive polymer electrolyte having high ion conductivity, which is safe even at relatively high temperatures without flowing. CONSTITUTION:A soluble electrolyte chloride compound is included in an organic polymer obtained by crosslinking a mixture polymer of an organic polymer component A composed of an organic compound, expressed by Formula I, having an average molecular weight of 1000-50000 and a terminal group Y such as an alkyl group, an alkenyl group or an aryl group and an organic polymer component B composed of the above organic compound having a terminal group Y such as an acryloyl group, a methacryloyl group, or an allyl group, wherein Z represents an active hydrogen including compound residual group; R1, a group expressed by Formula II (wherein (n) represents an integer from 0 to 25; and R, an alkyl group, an alkenyl group, or an aryl group having 1-20 carbon numbers R2, hydrogen or a methyl group; (k), an integer from 1 to 12; (p), an integer from 0 to 220; and (m), an integer from 1 to 240.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to an ion conductive polymer electrolyte, and more particularly to an ion conductive polymer electrolyte suitable for high temperature operation.

[0002]

2. Description of the Related Art Conventionally, as an ion conductive polymer electrolyte, for example, polyethylene oxide or a polyethylene oxide portion of a polyfunctional polyether molecular structure and a polypropylene oxide portion are randomly copolymerized. Known are organic polymer electrolytes obtained by doping an organic compound with an electrolyte salt and then crosslinking the same (see, for example, JP-A-62-249361), or thermoplastic homopolymers having no cross-linking with an electrolyte salt. Has been.

However, although the former crosslinked polymer has excellent mechanical properties without flowing even in a relatively high temperature range, its ionic conductivity is 80 ° C. because it is restricted by the segmental motion of the molecular chain due to crosslinking. Also at 10 ^-4 S / cm at most, sufficient ion conductivity cannot be obtained. In addition, the latter thermoplastic polymer generally has a higher ionic conductivity than the cross-linked polymer, but has the drawback that it easily flows at high temperatures. Therefore, these conventional ion-conducting polymer electrolytes are often unsatisfactory as electrolytes used for large-scale batteries that operate at relatively high temperatures (60 to 80 ° C.) for power flattening and electric vehicles.

The present invention has been made in view of the above problems of the prior art, and an object thereof is to ensure safe ionic conduction without flowing even at a relatively high temperature and high ionic conductivity. To provide a conductive polymer electrolyte.

[0005]

In order to achieve the above object, the gist of the present invention is "average molecular weight represented by the general formula 1
Organic polymer component A in which the terminal group Y in the organic compound of 000 to 50,000 is an alkoxy group, an alkenyloxy group or an aryloxy group "and" an organic polymer in which the terminal group Y in the organic compound is an acryloyl group, a methacryloyl group or an allyl group Component B, mixed polymer, "molecular weight hydroxyl group is substituted with an alkoxy group, an alkenyloxy group or an aryloxy group to give a molecular weight of 500 to
A mixed polymer of 50,000 end-modified polyalkylene oxide organic polymer component C "and" organic polymer component B "," molecular weight hydroxyl group substituted with acryloyl group, methacryloyl group or allyl group, molecular weight 500 to 5
4 kinds consisting of a mixed polymer of 0000 end-modified polyalkylene oxide organic polymer component D "and" the above organic polymer component A ", or a mixed polymer of" the above organic polymer component C "and" the above organic polymer component D " The ion-conductive polymer electrolyte is characterized in that a soluble electrolyte salt compound is contained in an organic polymer obtained by crosslinking any one of the mixed polymers of 1.

[0006]

[Chemical 3]

However, Z is an active hydrogen-containing compound residue, R
¹ is the following general formula (n is an integer of 0 to 25, R is a carbon number 1)
~ 20 alkyl groups, alkenyl groups or aryl groups)
R ² is hydrogen or a methyl group, and k
Is an integer of 1 to 12, p is an integer of 0 to 220, and m is 1 to 2.
An integer of 40 is shown.

[0008]

[Chemical 4]

The organic compound of the general formula and the polyalkylene oxide used as the raw materials of the above organic polymer component are "reacted with active hydrogen-containing compound and glycidyl ethers together with alkylene oxides" or "active hydrogen-containing compound, respectively". "Reacting a compound with alkylene oxides". Examples of the active hydrogen-containing compound include methanol, ethanol, ethylene glycol, propylene glycol, 1,
4-butanediol, glycerin, trimethylolpropane, sorbitol, sucrose, polyhydric alcohols such as polyglycerin, butylamine, 2-ethylhexylamine, ethylenediamine, hexamethylenediamine,
Amine compounds such as diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, aniline, benzylamine and phenylenediamine, phenolic active hydrogen compounds such as bisphenol A, hydroquinone and novolac, monomolecules such as monoethanolamine and diethanolamine Examples thereof include compounds having different active hydrogen-containing groups.

As the alkylene oxides, ethylene oxide, propylene oxide, 1,2-epoxybutane, 1,2-epoxypentane, 1,2-epoxyhexane, 1,2-epoxyheptane, 1,2-epoxyoctane. , 1,2-epoxynonane and the like having 4 to 4 carbon atoms
Examples of the α-olefin oxide of 9 and α-olefin oxide having 10 or more carbon atoms, styrene oxides and the like can be mentioned, and ethylene oxide and propylene oxide are preferable.

As the glycidyl ethers, compounds represented by the following general formula can be preferably used.

[0012]

[Chemical 5]

However, n represents an integer of 0 to 25, and R represents an alkyl group, an alkenyl group or an aryl group having 1 to 20 carbon atoms.

Further, the terminal-modified organic polymer component can be obtained as follows. That is, in the case of modifying the terminal group into an alkoxy group, an alkenyloxy group or an aryloxy group, a method of alcoholating the terminal hydroxyl group of the organic compound of the above general formula or polyalkylene oxide and then reacting with an alkyl halide or the like is adopted. When the terminal group is modified to an allyl group, an acryloyl group or a methacryloyl group, a method utilizing the esterification reaction between the terminal hydroxyl group and the unsaturated acid can be adopted. In each of the mixed polymers A and B, C and B, A and D or C and D in which two kinds of the organic polymer components A, B, C and D are mixed, the former component ( It is preferable that the ratio of A or C) is 50 to 98% and the ratio of the latter component (B or D) is 50 to 2%. Of these components, the crosslinkable components are B and D. If the proportion of these components exceeds 50%, the crosslink density will be too high and the ionic conductivity will decrease, while if it is less than 2%, the crosslinkability will decrease. Because it will be impossible.

After the end-modified organic polymer mixture thus obtained is doped with a soluble electrolyte salt compound exemplified below, a polymerization initiator or a sensitizer is used, if necessary, to heat, light, electron beam, etc. The ion-conductive polymer electrolyte of the present invention can be obtained by crosslinking under irradiation with actinic radiation. Examples of the soluble electrolyte salt compound include lithium fluoride, lithium chloride, lithium bromide, lithium iodide, lithium nitrate, lithium thiocyanate, lithium perchlorate, lithium trifluoromethanesulfonate, lithium tetrafluorofluoride, and bistrifluoro. Lithium methylsulfonylimide, lithium tristrifluoromethylsulfonylmethide, sodium thiocyanate, sodium perchlorate, sodium trifluoromethanesulfonate, sodium tetrafluorofluoride, potassium thiocyanate, potassium perchlorate, potassium trifluoromethanesulfonate , At least one selected from the group consisting of potassium tetrafluorofluoride, magnesium thiocyanate, magnesium perchlorate and magnesium trifluoromethanesulfonate, or two or more thereof. It can be.

[0016]

The ion conductive polymer electrolyte of the present invention is composed of an organic polymer obtained by crosslinking a polyether compound having a specific structure, so that it stabilizes the amorphous phase that contributes to ion conduction, and has high ion conductivity from low temperature to high temperature. Is expressed and does not flow even in a high temperature range.

[0017]

EXAMPLES Examples of the present invention will be described below. (Example 1) 18 g of glycerin and 730 g of methyldiethylene glycol glycidyl ether represented by the following formula
A mixture of 182 g of ethylene oxide and 182 g of ethylene oxide was reacted in the presence of a catalyst (2 g of potassium hydroxide), and desalted and purified to obtain 876 g of a polyether having a molecular weight of 4700 (calculated from a hydroxyl value).

[0018]

[Chemical 6]

Then, 1.1 equivalent of sodium methylate with respect to the number of hydroxyl groups is added to this polyether,
After removing methanol at 100 ° C. to alcoholate the terminal hydroxyl group, methyl iodide was added, and the terminal hydroxyl group was methoxylated by reacting at 80 ° C. for 6 hours (hereinafter referred to as “compound A-”, an organic polymer component A). Equivalent).

Further, glycerin having a molecular weight of 8000 was reacted with a mixture of ethylene oxide and propylene oxide (weight ratio: 4: 1) in the presence of a catalyst, and 1.2 equivalent of the number of terminal hydroxyl groups of the copolymer was reacted. Add acrylic acid,
Acryloyl terminal-modified polyalkylene oxide was obtained by reacting 50 times (by weight) the amount of the acrylic acid with 0.01 mol% of sulfuric acid at 110 ° C. for 8 hours (hereinafter referred to as “compound B-”, organic polymer). Ingredient D
Equivalent to).

The thus obtained "Compound A-" 3.
To 0 g and "Compound B-" 0.6 g, 0.4 g of lithium perchlorate and 0.006 g of a polymerization initiator (1-hydroxycyclohexyl phenyl ketone) were added and uniformly dissolved, and the mixture was poured onto a glass plate. 7 mW / cm ^{2 in} nitrogen atmosphere
By irradiating ultraviolet rays with the intensity of, an ion conductive polymer electrolyte having a thickness of 50 μm was obtained.

(Example 2) Diethylene glycol having a molecular weight of 3000 was reacted with a mixture of ethylene oxide and propylene oxide (weight ratio 4: 1) in the presence of a catalyst, and the number of terminal hydroxyl groups of the copolymer was 1. 1 equivalent of sodium methylate was added, methanol was removed under reduced pressure at 100 ° C. to alcoholate the terminal hydroxyl group, methyl iodide was added, and the mixture was reacted at 80 ° C. for 6 hours to obtain a terminal methoxy-modified polyalkylene oxide ( Hereinafter, referred to as "Compound A-", which corresponds to the organic polymer component C).

Then, to 3.2 g of "compound A-" and 0.4 g of "compound B-" synthesized by the method of Example 1, 0.4 g of lithium perchlorate and 0.02 g of a polymerization initiator (1- (Hydroxycyclohexyl phenyl ketone) is added and dissolved uniformly, and then it is flowed down on a glass plate and irradiated with ultraviolet rays for 2 minutes at an intensity of 7 mW / cm ² in a nitrogen atmosphere to obtain an ion conductive polymer electrolyte with a thickness of 50 μm. It was

Example 3 20 g of ethylenediamine, 5520 g of phenylhexaethylene glycol glycidyl ether represented by the following formula, and ethylene oxide 117
A mixture with 3 g was reacted in the presence of a catalyst (potassium hydroxide 9.4 g) to carry out desalting purification to obtain a molecular weight of 1992.
6590 g of 0 (calculated from hydroxyl value) polyether was obtained.

[0025]

[Chemical 7]

Then, 1.1 equivalent of acrylic acid and 2 parts of the acrylic acid are added to the polyether.
0 times the amount (weight) of toluene and sulfuric acid 0.01 mol% 8
An acryloyl-terminated modified organic polymer was obtained by reacting at 0 to 90 ° C. for 8 hours (hereinafter referred to as “compound B-”).
Which corresponds to the organic polymer component B).

Then, 0.7 g of "Compound B-2" and 2.9 g of "Compound A-2" synthesized by the method of Example 2 were added with 0.4 g of lithium perchlorate and 0.02 g of a polymerization initiator ( 1-Hydroxycyclohexyl phenyl ketone) and dissolved homogeneously, then flow down on a glass plate and irradiate with ultraviolet rays for 2 minutes at an intensity of 7 mW / cm ² in a nitrogen atmosphere to obtain an ion conductive polymer electrolyte with a thickness of 50 μm. Got

Example 4 3.1 g of "Compound A-" synthesized by the method of Example 1 and 0.5 g of "Compound B-" synthesized by the method of Example 3 were added to 0.4 g of lithium perchlorate.
g and 0.02 g of a polymerization initiator (1-hydroxycyclohexyl phenyl ketone) were added and uniformly dissolved, and then they were flowed down onto a glass plate and irradiated with ultraviolet rays for 2 minutes in a nitrogen atmosphere at an intensity of 7 mW / cm ² An ion conductive polymer electrolyte having a thickness of 50 μm was obtained.

COMPARATIVE EXAMPLE 1 3.6 g of "compound B-" synthesized by the method of Example 1 was added to 0.4 g of lithium perchlorate.
g and 0.006 g of a polymerization initiator (1-hydroxycyclohexyl phenyl ketone) were added and uniformly dissolved, and then the solution was allowed to flow down on a glass plate and irradiated with ultraviolet rays at an intensity of 7 mW / cm ² in a nitrogen atmosphere to give a thick film. An ion conductive polymer electrolyte having a length of 50 μm was obtained.

Comparative Example 2 3.6 g of "compound B-" synthesized by the method of Example 3 was added to 0.4 g of lithium perchlorate.
g and 0.006 g of a polymerization initiator (1-hydroxycyclohexyl phenyl ketone) were added and uniformly dissolved, and then the solution was allowed to flow down on a glass plate and irradiated with ultraviolet rays at an intensity of 7 mW / cm ² in a nitrogen atmosphere to give a thick film. An ion conductive polymer electrolyte having a length of 50 μm was obtained.

(Lithium Ion Conductivity Test) Next, in order to measure the ionic conductivity of the ion conductive polymer electrolytes of Examples 1 to 4 and Comparative Examples 1 and 2 thus obtained, each polymer electrolyte was tested. It was sandwiched between platinum plates, the AC impedance between the electrodes was measured, and complex impedance analysis was performed.

The results are shown in Table 1 below. An impedance analyzer (model: 4192A) manufactured by Yokogawa Hewlett-Packard Co. is used as the measuring machine.
As the measurement conditions, an applied voltage = 10 mV and a measurement use frequency = 5 Hz to 13 MHZ.

[0033]

[Table 1]

As is clear from Table 1, the ion conductive polymer electrolyte of the present invention exhibits excellent ionic conductivity, and particularly excellent ionic conductivity at relatively high temperatures.

On the other hand, since the polymers of Comparative Examples 1 and 2 consist of only the crosslinkable component, the crosslink density becomes too high and the ionic conductivity is low.

[0036]

EFFECT OF THE INVENTION The ion conductive polymer electrolyte according to the present invention shows stable and high ion conductivity from low temperature to high temperature. Further, since it has a crosslinked polymer electrolyte, it does not have the fluidity found in conventional thermoplastic polymer electrolytes, and can be safely used even at high temperatures.

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[Procedure amendment]

[Submission date] August 4, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] Claim 1

[Correction method] Change

[Correction content]

[Chemical 1] Where Z is an active hydrogen-containing compound residue, R1 is a group represented by the following general formula (n is an integer of 0 to 25, R is an alkyl group, an alkenyl group or an aryl group having 1 to 20 carbon atoms), and R2 is Consisting of hydrogen or a methyl group, k is 1 to 12
, P is an integer of 0 to 220, and m is an integer of 1 to 240.

[Chemical 2]

[Procedure Amendment 2]

[Document name to be amended] Statement

[Name of item to be corrected] 0005

[Correction method] Change

[Correction content]

[0005]

In order to achieve the above object, the gist of the present invention is "average molecular weight represented by the general formula 1
Terminal group Y is A in the organic compound of 000 to 50,000
A mixed polymer of "organic polymer component A which is an alkyl group, an alkenyl group or an aryl group " and "an organic polymer component B whose terminal group Y in the organic compound is an acryloyl group, a methacryloyl group or an allyl group", A mixed polymer of "organic polymer component C of terminal-modified polyalkylene oxide having a molecular weight of 500 to 50,000 substituted with an alkoxy group, an alkenyloxy group or an aryloxy group" and "the above organic polymer component B", "acryloyl group at a molecular terminal hydroxyl group, Mixed polymer of "organic polymer component D of terminal modified polyalkylene oxide having a molecular weight of 500 to 50,000 substituted with methacryloyl group or allyl group" and "organic polymer component A", or "organic polymer component C" and "organic polymer" Component D "mixed polymer In ion-conducting polymer electrolyte, characterized in that it comprises a soluble electrolyte salt compound to the organic polymer to four one of mixed polymer in the mixed polymer crosslinked consisting.

[Procedure 3]

[Document name to be amended] Statement

[Correction target item name] 0014

[Correction method] Change

[Correction content]

Further, the terminal-modified organic polymer component can be obtained as follows. That is, Al terminal groups
In the case of modifying to a kill group, an alkenyl group or an aryl group , it is possible to adopt a method of reacting an alkyl halide or the like with an alcoholate of the terminal hydroxyl group of the organic compound or polyalkylene oxide of the above general formula. In the case of modification with an allyl group, an acryloyl group or a methacryloyl group, a method utilizing the esterification reaction between the terminal hydroxyl group and the unsaturated acid can be adopted. In each of the mixed polymers A and B, C and B, A and D or C and D in which two kinds of the organic polymer components A, B, C and D are mixed, the former component ( It is preferable that the ratio of A or C) is 50 to 98% and the ratio of the latter component (B or D) is 50 to 2%. I mean,
Of these components, the crosslinkable components are B and D. If the proportion of these components exceeds 50%, the crosslink density becomes too high and the ionic conductivity decreases, while if it is less than 2%, crosslinking becomes impossible. Is.

Claims (3)

[Claims] 1. An average molecular weight of 1,000 represented by the general formula.
To 50000, the end group Y in the organic compound is an alkoxy group, an alkenyloxy group or an aryloxy group, and the end group Y in the organic compound.
A mixed polymer with an organic polymer component B in which is an acryloyl group, a methacryloyl group or an allyl group, a molecular weight of 500 to 500 in which a hydroxyl group at the terminal of the molecule is substituted with an alkoxy group, an alkenyloxy group or an aryloxy group.
00, a mixed polymer of an organic polymer component C of end-modified polyalkylene oxide and the above-mentioned organic polymer component B, an organic compound of end-modified polyalkylene oxide having a molecular weight of 500 to 50,000 in which a molecular terminal hydroxyl group is substituted with an acryloyl group, a methacryloyl group or an allyl group. A mixed polymer of polymer component D and the above organic polymer component A, or an organic polymer obtained by crosslinking any one of four mixed polymers consisting of the above mixed polymer of organic polymer component C and organic polymer component D. An ion conductive polymer electrolyte, characterized in that a soluble electrolyte salt compound is contained therein. [Chemical 1] However, Z is an active hydrogen-containing compound residue, R ¹ is a group represented by the following general formula (n is an integer of 0 to 25, R is an alkyl group, an alkenyl group or an aryl group having 1 to 20 carbon atoms), R 1 ² is hydrogen or a methyl group, and k is 1 to 12
, P is an integer of 0 to 220, and m is an integer of 1 to 240. [Chemical 2] 2. The ratio of the former component (A or C) of each mixed polymer in each of the mixed polymers A and B, C and B, A and D or C and D in which two kinds of organic polymer components are mixed. Is 50 to 98% and the ratio of the latter component (B or D) is 50 to 2%. 2. The ion conductive polymer electrolyte according to claim 1, wherein 3. The organic polymer is a mixed polymer, optionally using a polymerization initiator and / or a sensitizer, heat,
The ion-conductive polymer electrolyte according to claim 1, which is crosslinked under irradiation of actinic radiation such as light or electron beam.