CN1476123A - Gel electrolyte secondary cell and mfg. method thereof - Google Patents

Abstract

This invention is to improve battery characteristics of a gel electrolyte secondary battery and provide its manufacturing method. Since a precursor solution becomes easier to interpenetrate in a separator and an electrode when butyric acid is contained in the precursor solution of a gel electrolyte, a manufacturing process of the gel electrolyte secondary battery is improved. Furthermore, when the butyric acid is contained in the gel electrolyte, a gel electrolyte secondary battery with superior battery performance can be provided.

Description

Gel electrolyte secondary battery and manufacture method thereof

Technical field

The present invention relates to colloid substance as electrolytical gel electrolyte secondary battery and manufacture method thereof.Specifically, the present invention relates to so that high performance lighium polymer secondary battery to be provided is the gel electrolyte secondary battery and the manufacture method thereof of purpose.

Background technology

Now, the commercially available lithium primary battery or the electrolyte of lithium secondary battery use the material (electrolyte for lithium cells) that dissolves lithium salts in organic solvent.But, be easy to generate organic solvent and leak, or volatilization etc. to the liquid of outside batteries, exist long-term reliability to descend, electrolyte problem such as disperse in sealing process.

Therefore, in order to improve leakproof, fail safe, long preservation, the ionic conductivity macromolecule (gel electrolyte) that will have high ion-conductivity has been subjected to attention as electrolyte as one of means that address the above problem.For example, open clear 58-75779 communique (Japan) spy, the spy opens clear 59-149601 communique, the 4th, 792, No. 504 communiques of United States Patent (USP) etc., disclose the gel electrolyte of the solid state that electrolyte for lithium cells absorbed by colloid substance.

The disclosed up to now gel electrolyte that is used for battery can roughly be divided into 1. non-crosslinked thermoplasticity macromolecule, 2. contains the polymer of the oligomer of crosslinking group, and 3. combination of non-cross-linked polymer and cross-linked polymer etc. is 3 types.But these gel electrolytes also have the more part that needs improvement, research and develop from various angles.

Therefore; the gel electrolyte of the weakness that exists in the gel electrolyte shown in overcoming 1.～3.; promptly; to in macromolecular chain, contain oxirane (EO) unit or expoxy propane (PO) unit at least; the multi-functional acrylate of on its end and/or side chain, containing acryloyl group; or contain the multi-functional acrylate of methacryl; mix as precursor solution with electrolyte for lithium cells, it is carried out the crosslinked gel electrolyte that obtains by light, heat or electron ray etc. begin to draw attention.As its advantage, the precursor solution of gel electrolyte has the oxygenated hydrocarbon structure high with common electrolyte intermiscibility, and the retentivity of the electrolyte after crosslinked is good, thereby can bring favourable influence for part throttle characteristics, low-temperature characteristics etc.

For example; open in the flat 11-176452 communique the spy; put down in writing the terminal acryloyl group sex change oxygenated hydrocarbon polymer of four-functional group as the precursor of gel electrolyte, and disclose by electron ray irradiation and make it crosslinked, obtained having the cycle characteristics of the solid state battery of gel electrolyte.In addition, in the open 2001-210380 communique of spy, disclosed polymer battery, precursor as gel electrolyte, use simple function group, difunctional, trifunctional group acrylate, make its crosslinked gel electrolyte that obtains by ultraviolet irradiation, and in order to prevent the decomposition of aforementioned gel electrolyte in battery operation, its negative pole contains the graphite ion that adheres to amorphous carbon in its surface.The described battery of this communique, each precursor solution of dipping in anodal, negative pole and dividing plate and after crosslinked, form one.

In the manufacturing process of battery, between positive pole and negative pole, insert dividing plate, pack the exterior material of battery in coiling shape or a plurality of stacked form it after, inject the precursor solution of gel electrolyte.But precursor solution is difficult to soak into dividing plate and electrode, particularly negative pole.

In the past, (electrolyte for lithium secondary batteries of γ-BL) has the tendency that is difficult to soak into the low electrode of voidage to contain gamma-butyrolacton.In recent years, along with high-energy-densityization, the space of inside battery becomes minimum.So, in the time of will containing the precursor solution dipping dividing plate of γ-BL and electrode, can only soak into its surface, even crosslinkedly can not form good ion-conducting material.Therefore, the utilization ratio of active material descends, and locality discharges and recharges reaction, thereby battery behavior significantly descends.

In addition, for cross-linking method problem has been proposed also.Problem in ultraviolet irradiation is the transmittance to inside battery.That is, near scope that can irradiation ultraviolet radiation is defined in and seals, be difficult to be transmitted through the inside of electrode and dividing plate.Therefore, the crosslinked of precursor solution becomes insufficient, the precursor solution of remained unreacted.Its result works as impurity when battery operation, brings harmful effect for battery behavior.

In the electron ray irradiation, though be out of question as the transmittance of ultraviolet irradiation, crosslinked if the thickness of illuminated material is difficult to when thick.And then device costs an arm and a leg, and is difficult to the maximization of implement device, and its resultant costs uprises.

Therefore, utilize the cross-linking method of ultraviolet ray or electron ray, and be not suitable for the battery manufacture process of large-scale production.On the other hand, for heat cross-linking, with the thermal decomposition of electrolytic salt, the volatilization of electrolyte, the reactivity of thermal polymerization and battery component is the problem at center as the thermal endurance equitemperature characteristic of the aluminized coating of exterior material.

In addition, the active material that existence can not be by enlarging markedly positive pole and negative pole and the interface resistance between the gel electrolyte obtain battery behavior, unprecedented problem in electrolyte system in the past.

Summary of the invention

In view of the above problems, for various characteristics and the manufacture method of improving secondary cell are concentrated on studies, it found that, if in the precursor solution of gel electrolyte, contain butyric acid, then precursor solution infiltrates dividing plate and electrode easily, negative pole especially, thus can improve manufacture method, and then can improve the various characteristics of battery, finished the present invention thus.

Specifically, according to the present invention, a kind of gel electrolyte secondary battery is provided, it is characterized in that, by positive pole that contains the active material that can insert/break away from lithium ion and negative pole, and the gel electrolyte that is arranged between positive pole and the negative pole constitutes, and contains the butyric acid that concentration is 5～550ppm in this gel electrolyte.

And then, according to the present invention, a kind of manufacture method of gel electrolyte secondary battery is provided, this battery is by positive pole that contains the active material that can insert/break away from lithium ion and negative pole, and the gel electrolyte that is arranged between positive pole and the negative pole constitutes, and it is characterized in that, under the existence condition of butyric acid, to carry out crosslinked as the macromolecule of the raw material of gel electrolyte and make, so that make gel electrolyte contain the butyric acid that concentration is 5～550ppm.

Embodiment

Butyric acid is because have hydrophobic alkyl (CH simultaneously ₂CH ₂CH ₃) and the hydrophily carboxyl therefore (COOH), for example having will be as hydrophobic material such as the material with carbon element of negative electrode active material and the hydrophilic materials such as electrolyte for lithium secondary batteries that contain in gel electrolyte affine effect mutually.This effect can not disappear through crosslinked operation yet, therefore can improve battery behavior by contain butyric acid in gel electrolyte.

As butyric acid, any all has this effect in n-butyric acie, the isobutyric acid.But because the fusing point of n-butyric acie is-5.2 ℃, isobutyric fusing point is-46.1 ℃, so consider preferred isobutyric acid from the low-temperature characteristics below 0 ℃.

As gel electrolyte, can be useful in the known gel electrolyte that uses in the lithium polymer battery.And, also can contain the known electrolyte for lithium secondary batteries of in lithium ion battery, using, also be effective.

As the quantitative approach of butyric acid content in the electrolyte, for example, use oxolane or n-hexane equal solvent, extract this electrolyte that contains butyric acid out from gel electrolyte, measure by gas-chromatography or liquid chromatogram.

The preferred 5～550ppm of butyric acid content in gel electrolyte is more preferably 10～500ppm.If content less than 5ppm, can not fully improve active material and electrolytical compatibility, be difficult to obtain good battery behavior.On the other hand, if content is higher than 550ppm, butyric acid produces decomposition reaction along with discharging and recharging reaction, and efficiency for charge-discharge begins to descend.Therefore, be difficult to obtain good battery behavior, especially low-temperature characteristics.This is because the fusing point of n-butyric acie is-5.2 ℃.The content that is more preferably is for can improve 10～500ppm of battery behavior comprehensively.

Aforementioned gel electrolyte, constitute by the crosslinked body of the macromolecule that contains lithium salts, nonaqueous solvents, butyric acid, macromolecule, preferably contain PO/EO=0～5 of in its chain, containing oxirane (EO) unit or expoxy propane (PO) unit at least the trifunctional group acrylate polymer or copolymer and contain the EO unit or the polymer or the copolymer of the simple function group acrylate of PO/EO=0～5 of PO unit.

As the method for analyzing gel electrolyte, can use known method, for example be suitable for gel permeation chromatography or supercritical chromatography.For example, can use the mean molecule quantity of measuring by the former to be distributed in 200～3,000 and 7,000～9,000 crosslinked body.

By mixing trifunctional group acrylate's the polymer or the polymer or the copolymer of copolymer and simple function group acrylate, battery behavior does not only descend, and improves on the contrary in the present invention.By mixing, the flexibility of gel electrolyte increases, and therefore follows crosslinked expansion, shrinks and obtain buffering, and near the destruction of the gel electrolyte electrode that can prevent to produce in cyclic process promptly, can prevent crackle or breaks.And, when replacing the simple function group acrylate to use the bifunctional acrylate,, mix amount more than simple function group in order to obtain identical effect, its result, declines such as the confining force of liquid are not suitable as electrolyte for batteries.Index as the mechanical strength of gel electrolyte can exemplify hot strength, and preferred 0.05～25MPa.

The composition that the nonaqueous solvents of aforementioned electrolyte for lithium secondary batteries is more preferably, contain EC and γ-BL, contain the one or more solvents that are selected from diethyl carbonate (DEC), methyl ethyl carbonate (MEC), vinylene carbonate (VC) as the 3rd solvent, and the volume ratio of EC is 10～50%.Its reason is as follows.

If the volume ratio of EC is less than 10%, the graphite particle surface is difficult to closely cover with diaphragm, thereby produces the reaction of graphite particle and γ-BL, has the possibility that causes that cycle characteristics descends.On the other hand, if the volume ratio of EC greater than 50%, the viscosity of precursor solution uprises, and also is difficult to soak into dividing plate and electrode even add butyric acid.So, crosslinked after, in dividing plate and electrode, can not form sufficient gel electrolyte, thereby can not get good battery behavior.

In addition, in order to improve low-temperature characteristics, preferred γ-BL at least, nonaqueous solvents is overall relatively, and volume ratio is in 10～90% scopes.And then, be more preferably volume ratio in 30～70% scope.If the volume ratio of γ-BL less than 10%, is difficult to obtain sufficient low-temperature characteristics.On the other hand, if the volume ratio of γ-BL is higher than 90%, the graphite particle surface is difficult to cover with compact protective film, thereby the reaction that produces graphite particle and γ-BL has the possibility that causes that cycle characteristics descends.

In addition, in order to improve the electrode active material layer inside to precursor solution, or the impregnability of dividing plate base material inside, nonaqueous solvents is overall relatively, and preferably having volume ratio is 10～40% DEC, MEC.This is because the viscosity of DEC or MEC is lower than EC and γ-BL, has the effect that reduces precursor solution viscosity.If the volume ratio of DEC or MEC, does not then have the effect of adding less than 10%,, cause the distortion of exterior material and be not suitable for if the volume ratio of DEC or MEC greater than 40%, is difficult to suppress the oxidation Decomposition of gel electrolyte under hot environment.

In addition, the relative total amount of electrolyte for lithium secondary batteries is preferably added weight ratio and is 1～10% VC.By adding with this ratio, can form the diaphragm of EC at carbon surface, and form the thin of VC easily and compact protective film, inhibition gas produces, thereby can suppress the distortion of exterior material.Compact protective film raises because of gas produces the possibility that causes the exterior material distortion if the weight ratio of VC less than 1%, is difficult to form thin.On the other hand, if the weight ratio of VC greater than 10%, is difficult under hot environment to suppress the oxidation Decomposition of gel electrolyte, causes the distortion of exterior material and be not suitable for.

As the nonaqueous solvents except above-mentioned, can use the cyclic carbonate identical with EC, for example, propene carbonate, butylene, or the cyclic carbonate identical, linear carbonate with γ-BL, for example, diethyl carbonate etc.

As lithium salts, can exemplify known lithium salts such as lithium perchlorate, LiBF4, lithium hexafluoro phosphate, these can use a kind of or mix two or more uses.Can modulate electrolyte by dissolving lithium salts in being selected from the nonaqueous solvents of aforementioned substances.The concentration of lithium salts, relative nonaqueous solvents, preferred 0.8～2.5mol/l.The required ionic conductivity of discharge when if salinity less than 0.8mol/l, can not get to the acquisition high load capacity, if salinity is higher than 2.5mol/l, not only the cost of lithium salts can raise, and viscosity also can increase and be difficult to infiltrate in the electrode.And then melting lithium salts needs for a long time, industrial being not suitable for and can not be preferred.But the nonaqueous solvents, the lithium salts that use when this precursor solution of modulation are not limited to above-mentioned substance.

About negative pole, the active material that is more preferably can exemplify material with carbon element at graphite particle surface attachment amorphous carbon (below, be labeled as surperficial non-crystalline graphite).By using surperficial non-crystalline graphite, can suppress the decomposition of gel electrolyte or butyric acid.Particularly, the decomposition of butyric acid when easily suppressing to discharge and recharge, thus control the content of butyric acid easily.And then, the cell expansion that the gas that can prevent to produce in the decomposition reaction causes, the battery short circuit that causes thus, liquid leakage etc., thus improve the reliability of battery.

The surface non-crystalline graphite can be by being core with the high crystalline graphite material, by means such as known vapor phase method, liquid phase method, solid phase methods, adheres to amorphous carbon and obtain on the surface of this graphite material.

In surperficial non-crystalline graphite, relate to the pore of the per surface area of measuring by the BET method, because of causing obstruction to a certain degree adhering to of amorphous carbon, the preferred 1～5m of per surface area ²The scope of/g.If per surface area is greater than 5m ²/ g also increases with the contact area of the butyric acid that contains in gel electrolyte or this nonaqueous solvents, is easy to generate the decomposition reaction of these materials and is not suitable for.And then, because the adsorbance of the negative terminal surface of polymerization initiator increases in precursor solution, cause damaging the crosslinked of precursor solution, or first efficiency for charge-discharge is descended and be not suitable for.If per surface area is less than 1m ²/ g, because diminish with electrolytical contact area, electrochemical reaction rates is slack-off, the part throttle characteristics of battery descends and is not suitable for.

High crystalline graphite material as using in core can use known material.As the high crystalline material of core, the preferred use at the centre plane interval of X ray wide-angle diffraction method (002) face (d ₀₀₂) be 0.335～0.340nm, or Lc, La are the above material of 10nm.If d ₀₀₂Greater than 0.340nm, or Lc, La are less than 10nm, as the crystallinity of core and insufficient, so use it for when making surperficial non-crystalline graphite, the dissolving of lithium, (the current potential standard of Li is 0～300mV) capacity and insufficient being not suitable near the current potential part separating out.

And, as utilizing X ray wide-angle diffraction method to judge the method for grain size (Lc, La), can use known method, for example the method for " carbon materials experimental technique 1, p.55～63, (scientific and technical society) compiled by carbon materials association " record.

Specifically, test portion directly uses when being Powdered, if small sheet is then used the agate mortar pulverize.X ray standard high purity silicon powder with the about 15wt% of relative test portion, add and mix as the internal standard material, test portion is packed in the battery unit, is line source with the CuKa line of graphite monochromator monochromatization, measures the wide-angle x-ray diffraction curve by reflective diffraction meter method.The revisal of curve is not carried out the revisal of relevant Lorentz, the deflection factor, absorption factor, atomic scattering factor etc., and is used following straightforward procedure.

That is, search the baseline that is equivalent to (002) diffraction curve, obtain the revisal diffraction curve of (002) face.And in the revisal diffraction curve, half the locational so-called half price value β that uses in peak height utilizes Lc=(K λ)/(β cos θ) to try to achieve the axial grain size Lc of C.At this moment, λ is 1.5418 , and θ is the angle of diffraction.Same La also can measure.And, utilize 1580cm in the argon laser Raman spectrum relatively ^-1Near the 1360cm of peak strength ratio ^-1Near peak strength preferably (be more preferably below 0.4) below 0.5 than (below be labeled as the R value).If the R value surpasses 0.5, as the crystallinity of core and insufficient, when making surperficial non-crystalline graphite, in the dissolving of lithium, separate out near the capacity of current potential part also insufficient and be not suitable for.

And there is no particular limitation for the crystallinity of attachment portion, compares the low material of crystallinity, i.e. d basically with core by adopting ₀₀₂, big material such as R value, can obtain effect as surperficial non-crystalline graphite.In the X-ray diffraction, because of stipulating the volume property of its material, and when superficial layer was thin, difference became big and can't characterize volume property, for example, at this moment, can effectively use the R value of measuring in the Raman that can measure surface physical properties measures.

The material with carbon element of low-crystalline is more preferably d ₀₀₂Greater than 0.34nm, the R value is greater than 0.5 (more preferably greater than 0.4).These can set identical with the roasting condition of the various raw materials of CVD conditioned disjunction of the material with carbon element that adheres to from the teeth outwards, and the only virtual material with carbon element of making the surface is measured its physical property and regulation indirectly.

Then, the gel electrolyte in the gel electrolyte secondary battery makes as the macromolecule of gel electrolyte raw material crosslinkedly and make under the butyric acid existence condition, makes it contain the butyric acid that concentration is 5～550ppm.

Gel electrolyte, preferably by containing trifunctional group acrylate's the polymer or the copolymer of PO/EO=0～5 of oxirane (EO) unit or expoxy propane (PO) unit in the macromolecular chain at least, polymer or copolymer with the simple function group acrylate of PO/EO=0～5 of containing EO unit or PO unit, under the existence condition that contains electrolyte for lithium cells, polymerization initiator, butyric acid, carry out crosslinked and make.

Regulate the addition of butyric acid in the manufacture process, make crosslinked back in gel electrolyte, contain the butyric acid of concentration 5～550ppm.The addition of the butyric acid that adds in precursor solution in the manufacture process as required, adds more than the butyric acid density in the gel electrolyte of crosslinked back.As the addition of butyric acid, the total weight of relative precursor solution, the scope of preferred 9～560ppm.If butyric acid content is less than 9ppm, electrolyte is difficult to infiltrate in dividing plate and the electrode, can not get effect in manufacturing process.On the other hand, if butyric acid content surpasses 560ppm, though do not have problems in manufacturing process, the impaired possibility of crosslinked back battery behavior increases on the contrary.Addition is more preferably 15～510ppm.

In the raw material of gel electrolyte, can use the material of trifunctional PPG polyacrylate (trifunctional group acrylate's polymer or copolymer) as main body.Preferably have the polyether segment shown in the following general formula, and the polymerization position is polyfunctional group, so that polymer forms the ternary cross-linked structure.Its typical macromonomer (heavy polymer; Macromolecule, crosslinked and form the matrix of gel electrolyte) material that carried out esterification by acrylic acid for the terminal hydroxyl of PPG.PPG is by being raw material with trihydroxy alcohols such as glycerine, trimethylolpropanes, wherein adds EO separately or adds EO and PO polymerization and obtaining.

Insert the 12nd page of original text [changing 1]

(A ₁, A ₂, A ₃Expression contains the EO unit more than 3 at least, contains the residue of divalent of PO unit arbitrarily, and the number of PO and EO is in the scope of PO/EO=0～5, and EO+PO 〉=35)

Preferred 7,000～9,000 the scope of the mean molecule quantity of trifunctional acrylate copolymer or copolymer.If mean molecule quantity is less than 7,000, protect fluidity and go wrong, if greater than 9,000, needs were for a long time and industrial being not suitable for and can not be preferred when it dissolve.Particularly, when gel electrolyte contains electrolyte, trifunctional group acrylate's polymer or copolymer, compare easier formation ternary cross-linked structure with simple function group, difunctional, thereby mechanical strength height, good because of retentivity, so the ionic conductivity of gel electrolyte uprises, be suitable as electrolyte for batteries.

As the simple function group acrylate, preferably contain polyether segment, and the polymerization position is simple function group, so that polymer forms the one dimension cross-linked structure.The terminal hydroxyl that its typical macromonomer is a PPG is carried out the material of esterification by acrylic acid.PPG is by being raw material with monovalent alcohols such as methyl alcohol, ethanol, propyl alcohol, wherein adds EO separately or adds EO and PO carries out polymerization and obtains.

Insert the 13rd page of original text [changing 2]

(R is hydrogen atom or methyl, A ₄Expression contains oxirane (EO) unit more than 3 at least, contains the residue of divalent of expoxy propane (PO) unit arbitrarily, and the number of PO and EO is in the scope of PO/EO=0～5, and EO+PO 〉=35)

Preferred 200～3,000 the scope of the polymer of simple function group acrylate or the mean molecule quantity of copolymer.If mean molecule quantity less than 200, is difficult to form gelation,, when being dissolved, it needs for a long time and industrial being not suitable for and can not be preferred if greater than 3,000.The polymer or the copolymer of simple function group acrylate contain one-dimentional structure, and compare its guarantor's fluidity with the material of difunctional or trifunctional low, and gel electrolyte can not get sufficient ion and passes to rate.

Electrolyte content in the precursor solution of gel electrolyte be enough to form gel electrolyte in crosslinked back, and wherein electrolyte forms continuous phase, but it is surplus to leave nothing to be desired, and oozes out so that prevent the electrolyte time dependent from separating.For example, when polymer that mixes trifunctional group acrylate and simple function group acrylate and copolymer,, be controlled at 3: 97～15: 85 scope, can achieve the above object the weight ratio of macromonomer and this electrolyte.If the weight ratio of macromonomer is higher than 15%, ionic conductivity is insufficient, on the other hand, if the weight ratio of macromonomer is lower than 3%, be difficult to form gelation, carry out gelation even increase amount of initiator, also can not get sufficient mechanical, or the problem that exists this electrolyte after a period of time to ooze out.

And then, the polymer of simple function group acrylate or the addition of copolymer, the weight ratio in precursor solution preferred 0.5～7%.If the polymer of simple function group acrylate or the weight ratio of copolymer are higher than 7%, gel electrolyte itself is difficult to form three-dimensional crosslinking structure, so its ionic conductivity can not fully satisfy battery behavior.And the absolute magnitude of the macromonomer in the precursor solution is difficult to carry out gelation after a little while.In addition,, then do not produce the effect of mixing, can not solve above-mentioned problem if the weight ratio of the polymer of simple function group acrylate or copolymer is lower than 0.5%.

The viscosity of the precursor solution of gel electrolyte is preferably below 50mPas among the present invention.Consider that from the angle of simple dipping positive electrode active material layer and negative electrode active material layer the viscosity of precursor solution is low more good more.The viscosity of precursor solution is subjected to the influence of mix proportion, lithium salt, temperature of macromonomer and nonaqueous solvents etc.And, as the means that reduce viscosity, the temperature of the precursor solution that can raise, but in order not influence polymerization initiator and this nonaqueous solvents, preferably operating below 90 ℃.In order to improve dipping efficient, speed, also can be pressed into, operation such as vacuum impregnation.As cross-linking method, except the method for heating, can use the method for the luminous energy that utilizes ultraviolet ray, electron ray, visible light etc.Also can use polymerization initiator also very important as required.In utilizing ultraviolet cross-linking method, preferably add the following polymerization initiator of hundreds of proportions by subtraction especially.

As polymerization initiator, can exemplify neopentanoic acid classes such as the own ester of peroxidating neopentanoic acid uncle (10 hours half life temperature 53 ℃, activate energy 28.3kcal/mol), the peroxidating neopentanoic acid tert-butyl ester (10 hours half life temperature 54 ℃, activate energy 28.6kcal/mol); Two-3,5, peroxidating two acyl classes such as 5-trimethyl peroxidating hexanol (10 hours half life temperature 60 ℃, activate energy 29.7kcal/mol), laurylperoxide acyl (10 hours half life temperature 61 ℃, activate energy 29.9kcal/mol), peroxidating stearyl (10 hours half life temperature 62.4 ℃, activate energy 30.3kcal/mol), meta-methoxy benzoyl peroxide (10 hours half life temperature 73.1 ℃, activate energy 30.6kcal/mol), peroxidating isobutyryl (10 hours half life temperature 33 ℃, activate energy 25.6kcal/mol); (half life temperature was 46 ℃ in 10 hours for new peroxide tert-butyl caprate, activate energy 26.8kcal/mol), peroxidating neodecanoic acid-1,1,3, (half life temperature was 41 ℃ in 10 hours for 3-tetramethyl butyl ester, activate energy 27.2kcal/mol), (half life temperature was 44 ℃ in 10 hours for the own ester of peroxidating neodecanoic acid uncle, activate energy 34.8kcal/mol), α, (half life temperature was 35.9 ℃ in 10 hours for α '-two (peroxidating neodecanoic acid) 6-diisopropyl benzene ester, activate energy 25.5kcal/mol), (half life temperature was 38 ℃ in 10 hours for neodecanoic acid α-isopropylbenzene ester, activate energy 27.2kcal/mol) peracid alkyl esters such as; (half life temperature was 43 ℃ in 10 hours for peroxy dicarbonate two-3-methoxyl group butyl ester, activate energy 34.1kcal/mol), (half life temperature was 44 ℃ in 10 hours for two (the 4-tert-butyl group hexamethylene) esters of peroxy dicarbonate, activate energy 30.2kcal/mol), (half life temperature was 40.3 ℃ in 10 hours for the peroxy dicarbonate di-n-propyl ester, activate energy 27.2kcal/mol), (half life temperature was 45 ℃ in 10 hours for di-isopropyl peroxydicarbonate, activate energy 30.4kcal/mol), (half life temperature was 41.4 ℃ in 10 hours for peroxidating neodecanoic acid-1-cyclohexyl-1-methyl ethyl ester, activate energy 27.8kcal/mol), (half life temperature was 43.1 ℃ in 10 hours for peroxy dicarbonate two-2-ethoxy ethyl ester, activate energy 30.0kcal/mol), (half life temperature was 43.6 ℃ in 10 hours for ester for two carbonic acid two (peroxidating of 2-ethyl is own), activate energy 3 1.1kcal/mol), (half life temperature was 46.7 ℃ in 10 hours for ester for two carbonic acid two (3-methyl-3-methoxyl group peroxidating fourth), activate energy 27.1kcal/mol) percarbonic acid class etc. such as.These polymerization initiators can be used alone or in combination.

In the secondary cell that constitutes by positive pole, gel electrolyte, negative pole, because 10 hours half life temperatures of polymerization initiator are about 40 ℃, so the preferred polymerization initiator that uses in the hot inaccessible temperature of the fiber that is used for dividing plate and the bonding softening point temperature scope with resin that is used for dividing plate.Specifically, preferably using 10 hours half life temperatures is the initator below 90 ℃ more than 40 ℃.If less than 40 ℃, be not suitable for because of polymerization initiator is unstable.And, be 90 ℃ of obtaining 10 hour half-life if surpass, in heat treated, cause the deterioration of nonaqueous solvents or decomposition easily and be not suitable for.

In order to reach the present invention, new peroxide tert-butyl caprate, the own ester of peroxidating neopentanoic acid uncle, the peroxidating neopentanoic acid tert-butyl ester of preferred especially peracid alkyl esters.These three kinds of polymerization initiators can not bring harmful effect to butyric acid in the precursor solution or electrod assembly etc., are fit to use.

Polymerization initiator relatively adds polymer or the material of copolymer and the gross mass of electrolyte for lithium secondary batteries of simple function group acrylate in trifunctional group acrylate's polymer or copolymer, preferably add 1～5,000ppm.The addition of polymerization initiator, preferably as far as possible little, so that the reactions such as decomposition of initiator of minimizing when discharging and recharging.But if the amount of initator is very few, polymerization reaction is insufficient, the macromonomer of possible remained unreacted and being not suitable for.Because above-mentioned reason, the addition of polymerization initiator comprises the gross mass of macromonomer and nonaqueous solvents relatively, and is preferred 1～5, and 000ppm wherein is more preferably 100～1,000ppm.

Below, describe for the secondary cell that uses above-mentioned gel electrolyte.

Battery is made by following operation.

A) making of negative pole

Negative pole manufacture method one described below for example.

In mortar, use the dissolution with solvents binding agent, disperse carbon material used as anode.In dispersion treatment, can use mixer, ball mill, coating shaking machine, dynamic grinder etc., modulation material with carbon element, the homodisperse paste of binding agent.This paste is coated on the metal forming of collector body, it is predrying 40～100 ℃ of enforcements.Afterwards, heat-treat, and in order to make its active material density that reaches regulation, the working pressure machine carries out compression molding at 150 ℃.Can use common roll squeezer in the compression molding.There is no particular limitation for the material of the pressure face of these forcing presses, spinning solution, temperature, atmosphere etc.Afterwards,, and about 150 ℃, carry out drying under reduced pressure in order to remove moisture at uncoated part welding lead, with it as negative pole.

As the material with carbon element of negative electrode active material, can use the negative material of known lithium ion battery.About preferred 0.1～150 μ m of the particle size distribution of material with carbon element.As binding agent, can use polytetrafluoroethylene (PTFE), the poly-inferior ethene of fluorine (PVdF) etc., but be not limited to these materials.Mixing ratio, relative activity material 100 weight portions, preferred 1～30 weight portion of binding agent.In order to make the high-energy-density battery, the preferred 1.4g/cm of the density of negative electrode active material ³More than.And in order to improve caking property, preferably the temperature about the binding agent fusing point is heat-treated in negative pole is made.

B) Zheng Ji making

Anodal manufacture method one described below for example.

In mortar, use the dissolution with solvents binding agent, dispersed activity material and conductive agent.In dispersion treatment, can use ball mill, coating shaking machine, dynamic grinder etc., modulation active material, conductive agent, the homodisperse paste of binding agent.This paste is coated on the metal forming of collector body, it is predrying 40～100 ℃ of enforcements.Afterwards, heat-treat, and in order to make its active material density that reaches regulation, the working pressure machine carries out compression molding at 150 ℃.Can use common roll squeezer in the compression molding.There is no particular limitation for the material of the pressure face of these forcing presses, spinning solution, temperature, atmosphere etc.Afterwards,, and about 150 ℃, carry out drying under reduced pressure in order to remove moisture at uncoated part welding lead, with it as positive pole.

As positive active material, can use LiCoO ₂, LiNiO ₂, LiMnO ₂, LiFeO ₂, or LiA that should series _1-xT _xO ₂(this moment, A was any of Fe, Co, Ni, Mn, and T represents transition metal, 4B family or 5B family metal.0≤X≤1), LiMn ₂O ₄Positive electrode etc. known lithium ion battery.

As conductive agent, can use material with carbon elements such as acetylene black, or powdered graphite etc., but be not limited to these materials.

As binding agent, can use PTFE, PVdF etc., but be not limited to these materials.

Mixing ratio, relative activity material 100 weight portions, preferred 1～50 weight portion of conductive agent, preferred 1～30 weight portion of binding agent.In order to make the high-energy-density battery, the preferred 2.8g/cm of the density of positive active material ³More than, be more preferably 3.0g/cm ³More than.In order to improve caking property, preferably the temperature about the binding agent fusing point is heat-treated in positive pole is made.

Anodal, negative pole basically will be by the immobilized various active materials of binding agent, carry out on as the metal forming of collector body stacked.Material, the shape of aforementioned collector body are unqualified, can use for positive and negative electrode active material and electrolyte, at chemistry, the stable conductor of electrochemical properties.As the material of metal forming, can use aluminium, stainless steel, copper, nickel etc.Wherein, consider from the angle of electrochemical stability, ductility and economy, the anodal preferred aluminium foil that uses, negative pole preferably uses Copper Foil.And the form of positive pole, negative electrode collector can exemplify forms such as mesh, mesh metallic plate except metal forming.

C) modulation of gel electrolyte precursor solution

For example, can modulate by the following method.

In EC+ γ-BL, mix in the nonaqueous solvents of the 3rd solvent dissolving lithium salts, modulation electrolyte for lithium secondary batteries.In this electrolyte, adding mean molecule quantity is 7,000～9,000 trifunctional polymerizing acrylic acid thing or copolymer (TA) and mean molecule quantity are 200～3,000 simple function group polymerizing acrylic acid thing or copolymer, add the polymerization initiator and the butyric acid of ormal weight again, obtain precursor solution.

D) assembling of battery

As the above-mentioned positive pole that obtains and negative pole between the assembly (electrode group) of configuration dividing plate make coiling shape, and insert in the bag as the stacked resin film matter of the A1 of exterior material, be infused in c) in seal this bag after the precursor solution of modulation.It in 20 minutes～100 hours scope of 40～90 ℃ of heating, is made it crosslinked and finish battery.

The shape of electrode group can directly adopt coiling shape, also can adopt the flat shape with its radial compression.In addition, also can be with positive pole and negative pole, by dividing plate therebetween, bending is repeatedly.With the method for electrode group formation coiling shape, can use known method.As compression method, can use the known method of exerting pressure with required pressure multi stage.

As the dividing plate that is used to keep gel electrolyte, can exemplify nonwoven fabrics and fabrics such as electrical insulating property synthetic resin fiber, glass fibre, natural fiber.Wherein, consider nonwoven fabrics such as the inferior ethene of preferred polychlorostyrene, polyethylene, polypropylene from the quality of stability equal angles.In the nonwoven fabrics of these synthetic resin, when the battery abnormal heating, have because of hot dividing plate dissolvedly, the additional material that cuts off the both positive and negative polarity function is considered from the angle of fail safe, also can be suitable for.

There is no particular limitation for the thickness of dividing plate, only needs to keep the liquid of necessary amount, and have the thickness that can prevent anodal and negative pole short circuit and get final product, and can use the material about 0.01～1mm usually, about preferred 0.02～0.05mm.Preferred its air permeability of these base materials is 1～500sec/cm ³,, and have the intensity that can prevent internal short-circuit of battery so that can keep low inside battery resistance.

In addition, secondary cell also can be made by the following method: impregnated precursor solution in positive pole, negative pole and dividing plate, after the heat cross-linking, integrally formed coiling shape is inserted in the bag of exterior material.But the former method because two interfaces of anodal (gel electrolyte), negative pole are not bonding, but by being cross-linked to form, can reduce inside battery resistance so compare with the latter's method.

In addition, also can insert after the bag of exterior material by positive pole/dividing plate/negative pole is a plurality of overlapping, be infused in c) in the precursor solution of modulation, seal this bag and make.

The battery face shaping except as above-mentioned cascade type, can be suitable for different shapes such as cylindrical shape, square, button (coin) shape, plate shape.As exterior material, can exemplify metal, resin etc.For example, in cylindrical shape or square battery, in jar, insert coiling shape electrode group, make jar and the electrical connection of electrode group.Inject precursor solution, hush panel is sealed and by gas-tight seal a hush panel and a jar insulation are sealed by insulating packing, the utilization heating is carried out crosslinked and is made battery.

At this moment, the safety valve with safety element can be used as hush panel.Safety element for example, as preventing overcurrent element, has fuse, bimetallic element, PTC element etc.And, except that safety valve, prevent the high method of interior voltage rise of battery can, can use the method that in packing ring, forms be full of cracks, form the method that chaps in hush panel, in battery can, form the method for indentation etc.In addition, also can use to embed and prevent to overcharge and the external circuit of overdischarge.In addition, if button shaped cell can in its tank filling, be injected precursor solution by forming hemispheric positive pole and negative pole, by the insulating packing fixed cap, the utilization heating is carried out crosslinked and is made battery.Dividing plate can use the nonwoven fabrics of synthetic resin system etc.

E) the butyric acid content in the gel electrolyte

In the gel electrolyte butyric acid content quantitatively, by the gel electrolyte solvent extraction, try to achieve the butyric acid content in the extract and carry out.Specifically, gel electrolyte is immersed in oxolane (THF) or the n-hexane equal solvent, the extraction of carrying out after the ultrasonic Treatment more than 24 hours is handled.Filter aforementioned gained extract, utilize the weight of gas-chromatography or the quantitative butyric acid of liquid chromatogram.With income value, convert by following calculating formula, can be in the hope of the butyric acid content in the extract.This butyric acid content is as the butyric acid content in the gel electrolyte.

Butyric acid content (ppm)=butyric acid weight (mg)/extract weight (g)

And, at battery of the present invention, to compare with the butyric acid addition, its content diminishes.Can infer that this is because there is loss when extraction is handled.

F) evaluation of battery

Discharge and recharge the running experiment, charge to cell voltage with certain current value and reach 4.1～4.2V.Cell voltage reaches after 4.1～4.2V, charges to total charging interval with certain voltage and reaches 12 hours.Discharge reaches 2.7～3.0V with certain electric current to proceeding to cell voltage.

And cell evaluation all carries out in clean control box under inert gas atmosphere.As inert gas, use argon gas, nitrogen etc. usually.

Embodiment

Below, utilize embodiment and comparative example, specify the present invention and effect thereof, but the present invention is not limited to the following examples.And it is positive pole and negative pole about 0.8Ah that the battery of embodiment 1～19 and comparative example 1～2 all has battery capacity.

Embodiment 1

Make the battery of embodiment 1 by following operation.

A) making of negative pole

Material with carbon element uses surperficial non-crystalline graphite (average grain diameter 12 μ m, d ₀₀₂=0.336nm, R value=0.35, per surface area 1～2m ²/ g).In mortar,, disperse surperficial non-crystalline graphite with solvent N-N-methyl-2-2-pyrrolidone N-(NMP) dissolving binding agent PVdF.In dispersion treatment, use the mixing and blending machine of twin shaft planetary mode, modulation material with carbon element, the homodisperse paste of binding agent.The composition of negative pole, material with carbon element position 100 weight portions, PVdF position 10 weight portions.This paste is coated on thickness is about on the 20 μ m Copper Foils, it is predrying 50～70 ℃ of enforcements.Afterwards, carry out heat treatment in 12 hours at 150 ℃, and in atmosphere, utilize the roll squeezer compression molding, make the density of active material reach 1.5g/cm ³About, at uncoated part welding nickel foil (50 μ m) lead-in wire.Afterwards, in order to remove moisture, use as negative pole about 150 ℃ of drying under reduced pressure that carry out 12 hours.

And, as utilizing X ray wide-angle diffraction method to measure centre plane (d at interval ₀₀₂) and the method for grain size (Lc, La), use known method, for example " carbon materials experimental technique 1, p.55～63, (scientific and technical society) compiled by carbon materials association " or (Japan) spy open the method for putting down in writing among the clear 61-111907.Be used to try to achieve form factor the K (=Lc β cos θ/λ of grain size; β wherein: half value is wide, θ: d ₀₀₂Angle, λ: be 0.9 wavelength of X ray).And average grain diameter utilizes laser diffraction formula particle size distribution meter (island Jin She makes SALD1100) to measure, and the peak value in particle size distribution is as average grain diameter.

B) Zheng Ji making

Active material uses cobalt acid lithium LiCoO ₂(average grain diameter 10 μ m).In mortar, dissolve PVdF, disperse above-mentioned active material and conductive agent acetylene black (AB) with NMP.In dispersion treatment, can use the mixing and blending machine of twin shaft planetary mode, modulation active material, conductive agent, the homodisperse paste of binding agent.Anodal composition, LiCoO ₂Be 100 weight portions, AB is 5 weight portions, and PVdF is 5 weight portions.With this muddle cloth thickness is on the aluminium foil of 20 μ m, and it is predrying 50～70 ℃ of enforcements, after 150 ℃ are heat-treated, carries out compression molding.Common roll squeezer is used in compression molding in atmosphere, proceed to active material density and reach 3.0g/cm ³About.At uncoated part welding nickel foil (50 μ m) lead-in wire.And then, about 150 ℃, carry out drying under reduced pressure in order to remove moisture, with it as positive pole.

C) modulation of the precursor solution of gel electrolyte

LiBF ₄Be dissolved among EC+ γ-BL+EMC (volume ratio 14: 56: 20), make its concentration that reaches 2.5mol/l, this is added VC 2wt%, the modulation electrolyte for lithium secondary batteries.In this electrolyte, mix mean molecule quantity and be 7,500～9,000 TA 2.4wt% and mean molecule quantity and be 200～300 simple function group polymerizing acrylic acid thing or copolymer (GX) 0.6wt%, thereby make aforementioned electrolyte reach 97wt%.Then, add new peroxide tert-butyl caprate (BPN) 250ppm, the peroxidating neopentanoic acid tert-butyl ester (BPP) 250ppm and butyric acid 15ppm, obtain precursor solution as polymerization initiator.

D) assembling of battery

Between above-mentioned positive pole that obtains and negative pole, accompany microporous polyethylene film (thickness 25 μ m, air permeability 380sec/cm as the dividing plate base material ³), it is made coiling shape.Arrive this coiling body radial compression flat.Compression is undertaken by dividing for 5 stages exerted pressure with required pressure.The electrode group that forms coiling shape is inserted in the bag as the stacked resin film matter of the A1 of exterior material, is infused in c) in the precursor solution that obtains, seal this bag.By making it crosslinked 60 ℃ of heating of carrying out 72 hours it, finish battery.Embodiment 2

Make the battery of embodiment 2 by following operation.

A) making of negative pole

Except surperficial non-crystalline graphite (average grain diameter 18 μ m, d ₀₀₂=0.336nm, R value=0.5, per surface area 1～2m ²/ g) and the composition of negative pole to make material with carbon element into be 100 weight portions, PVdF is outside 8 weight portions, makes negative pole by the method identical with embodiment 1.

B) Zheng Ji making

Repeat and embodiment 1 identical operations, make anodal.

C) modulation of the precursor solution of gel electrolyte

LiPF ₆Be dissolved among EC+ γ-BL+DMC (volume ratio 20: 50: 30), make its concentration that reaches 2.0mol/l, this is added VC 3wt%, the modulation electrolyte for lithium secondary batteries.In aforementioned electrolyte 95wt%, mix mean molecule quantity and be 7,000～9,000 TA 2.5wt% and mean molecule quantity and be 200～300 GX 2.5wt%.Then, add the BPN 200ppm as polymerization initiator, BPP 250ppm and butyric acid 51ppm obtain precursor solution.

D) assembling of battery

Except microporous polyethylene film (thickness 25 μ m, air permeability 480sec/cm ³) and utilize the crosslinked condition of heating to change into outside 70 ℃, 70 hours, make battery by the method identical with embodiment 1.

Embodiment 3

Make the battery of embodiment 3 by following operation.

A) making of negative pole

Except surperficial non-crystalline graphite (average grain diameter 25 μ m, d ₀₀₂=0.336nm, R value=0.25, per surface area 1～2m ²/ g) and the composition of negative pole to make material with carbon element into be 100 weight portions, PVdF is outside 9 weight portions, makes negative pole by the method identical with embodiment 1.

B) Zheng Ji making

Repeat and embodiment 1 identical operations, make anodal.

C) modulation of the precursor solution of gel electrolyte

LiBF ₄Be dissolved among EC+ γ-BL+MEC (volume ratio 25: 55: 20), make its concentration that reaches 1.8mol/l, this is added VC 3wt%, the modulation electrolyte for lithium secondary batteries.In aforementioned electrolyte 97wt%, mix mean molecule quantity and be 7,500～9,000 TA 2.4wt% and mean molecule quantity and be 200～300 GX 0.6wt%.Then, add the BPP 150ppm as polymerization initiator, the peroxidating neopentanoic acid tert-butyl ester (HPP) 150ppm and butyric acid 102ppm obtain precursor solution.

D) assembling of battery

Except the crosslinked condition of utilizing heating is changed into 80 ℃, 65 hours, make battery by the method identical with embodiment 2.

Embodiment 4

Make the battery of embodiment 4 by following operation.

A) making of negative pole

Repeat and embodiment 1 identical operations, make negative pole.

B) Zheng Ji making

Repeat and embodiment 1 identical operations, make anodal.

C) modulation of the precursor solution of gel electrolyte

LiClO ₄Be dissolved among EC+ γ-BL+DEC (volume ratio 30: 60: 10), make its concentration that reaches 1.5mol/l, this is added VC 2wt%, the modulation electrolyte for lithium secondary batteries.In aforementioned electrolyte 93wt%, mix mean molecule quantity and be 7,500～9,000 TA 3.5wt% and mean molecule quantity and be the polymer and copolymer (MA) 3.5wt% of 2,800～3,000 simple function group acrylate.Then, add BPN 300ppm and butyric acid 254ppm, obtain precursor solution as polymerization initiator.

D) assembling of battery

Except the crosslinked condition of utilizing heating is changed into 65 ℃, 71 hours, make battery by the method identical with embodiment 2.

Embodiment 5

Make the battery of embodiment 5 by following operation.

A) making of negative pole

Repeat and embodiment 2 identical operations, make negative pole.

B) Zheng Ji making

Repeat and embodiment 1 identical operations, make anodal.

C) modulation of the precursor solution of gel electrolyte

LiBF ₄Be dissolved among EC+ γ-BL+MEC (volume ratio 30: 40: 30), make its concentration that reaches 2.2mol/l, this is added VC 1.5wt%, the modulation electrolyte for lithium secondary batteries.In aforementioned electrolyte 96wt%, add mean molecule quantity and be 7,000～9,000 TA3.0wt% and mean molecule quantity and be 2,800～3,000 MA 1.0wt%.Then, add BPP 200ppm and butyric acid 452ppm, obtain precursor solution as polymerization initiator.

D) assembling of battery

Except the crosslinked condition of utilizing heating is changed into 60 ℃, 72 hours, make battery by the method identical with embodiment 2.

Embodiment 6

Make the battery of embodiment 6 by following operation.

A) making of negative pole

Repeat and embodiment 3 identical operations, make negative pole.

B) Zheng Ji making

Repeat and embodiment 1 identical operations, make anodal.

C) modulation of the precursor solution of gel electrolyte

LiBF ₄Be dissolved among EC+ γ-BL+MEC (volume ratio 25: 55: 20), make its concentration that reaches 1.75mol/l, this is added VC 3wt%, the modulation electrolyte for lithium secondary batteries.In aforementioned electrolyte 97wt%, add mean molecule quantity and be 7,000～9,000 TA2.4wt% and mean molecule quantity and be 2,800～3,000 MA 0.6wt%.Then, add HPP 300ppm and butyric acid 503ppm, obtain precursor solution as polymerization initiator.

D) assembling of battery

Except the crosslinked condition of utilizing heating is changed into 80 ℃, 60 hours, make battery by the method identical with embodiment 2.

Embodiment 7

Make the battery of embodiment 7 by following operation.

A) making of negative pole

Repeat and embodiment 1 identical operations, make negative pole.

B) Zheng Ji making

Repeat and embodiment 1 identical operations, make anodal.

C) modulation of the precursor solution of gel electrolyte

LiBF ₄Be dissolved among EC+ γ-BL+MEC (volume ratio 24: 56: 20), make its concentration that reaches 2.0mol/l, this is added VC 3wt%, the modulation electrolyte for lithium secondary batteries.In aforementioned electrolyte 96wt%, mix mean molecule quantity and be 7,500～9,000 TA 3wt% and mean molecule quantity and be 200～300 GX 1.0wt%.And then, add BPN 200ppm and butyric acid 9ppm as polymerization initiator, obtain precursor solution.

D) assembling of battery

By the method identical, make battery with embodiment 1.

Embodiment 8

Make the battery of embodiment 8 by following operation.

A) making of negative pole

Repeat and embodiment 2 identical operations, make negative pole.

B) Zheng Ji making

Repeat and embodiment 1 identical operations, make anodal.

C) modulation of the precursor solution of gel electrolyte

Except the addition of butyric acid is changed into the 13ppm, obtain precursor solution by the method identical with embodiment 2.

D) assembling of battery

Make battery by the method identical with embodiment 2.

Embodiment 9

Make the battery of embodiment 9 by following operation.

A) making of negative pole

Repeat and embodiment 3 identical operations, make negative pole.

B) Zheng Ji making

Repeat and embodiment 1 identical operations, make anodal.

C) modulation of the precursor solution of gel electrolyte

Except the addition of butyric acid is changed into the 511ppm, obtain precursor solution by the method identical with embodiment 3.

D) assembling of battery

Make battery by the method identical with embodiment 3.

Embodiment 10

Make the battery of embodiment 10 by following operation.

A) making of negative pole

Repeat and embodiment 1 identical operations, make negative pole.

B) Zheng Ji making

Repeat and embodiment 1 identical operations, make anodal.

C) modulation of the precursor solution of gel electrolyte

Except the addition of butyric acid is changed into the 550ppm, obtain precursor solution by the method identical with embodiment 4.

D) assembling of battery

Make battery by the method identical with embodiment 4.

Embodiment 11

Make the battery of embodiment 11 by following operation.

A) making of negative pole

Repeat and embodiment 2 identical operations, make negative pole.

B) Zheng Ji making

Repeat and embodiment 1 identical operations, make anodal.

C) modulation of the precursor solution of gel electrolyte

LiBF ₄Be dissolved among EC+ γ-BL+MEC (volume ratio 25: 55: 20), make its concentration that reaches 1.8mol/l, this is added VC 3wt%, the modulation electrolyte for lithium secondary batteries.In aforementioned electrolyte 96wt%, the mixing mean molecule quantity is 7,500～9,000 TA 4wt%.Then, add BPN 150ppm and butyric acid 100ppm, obtain precursor solution as polymerization initiator.

D) assembling of battery

Make battery by the method identical with embodiment 6.

Embodiment 12

Make the battery of embodiment 12 by following operation.

A) making of negative pole

Repeat and embodiment 3 identical operations, make negative pole.

B) Zheng Ji making

Repeat and embodiment 1 identical operations, make anodal.

C) modulation of the precursor solution of gel electrolyte

LiBF ₄Be dissolved among EC+ γ-BL+DEC (volume ratio 20: 60: 20), make its concentration that reaches 1.8mol/l, this is added VC 3wt%, the modulation electrolyte for lithium secondary batteries.In aforementioned electrolyte 97wt%, mix mean molecule quantity and be 7,500～9,000 TA 2.5wt% and the mean molecule quantity shown in following general formula and be 3,500～4,500 bifunctional acrylate's polymer and copolymer (DA) 1.5wt%.

Insert the 29th page of original text [changing 3]

(A ₅Expression contains the EO unit more than 3 at least, contains the residue of divalent of PO unit arbitrarily, and the number of PO and EO is in the scope of PO/EO=0～5)

Then, add the BPN 150ppm as polymerization initiator, BPP 150ppm and butyric acid 101ppm obtain precursor solution.

D) assembling of battery

Make battery by the method identical with embodiment 2.

Embodiment 13

Make the battery of embodiment 13 by following operation.

A) making of negative pole

Repeat and embodiment 1 identical operations, make negative pole.

B) Zheng Ji making

Repeat and embodiment 1 identical operations, make anodal.

C) modulation of the precursor solution of gel electrolyte

LiBF ₄Be dissolved among EC+ γ-BL+MEC (volume ratio 9: 71: 20), make its concentration that reaches 1.8mol/l, this is added VC 3wt%, the modulation electrolyte for lithium secondary batteries.In aforementioned electrolyte 96wt%, mix mean molecule quantity and be 7,500～9,000 TA 3wt% and mean molecule quantity and be 200～300 GX 1.0wt%.And then, adding BPN 150ppm as polymerization initiator, BPP 150ppm and butyric acid 500ppm obtain precursor solution.

D) assembling of battery

Make battery by the method identical with embodiment 2.Embodiment 14

Make the battery of embodiment 14 by following operation.

A) making of negative pole

Repeat and embodiment 2 identical operations, make negative pole.

B) Zheng Ji making

Repeat and embodiment 1 identical operations, make anodal.

C) modulation of the precursor solution of gel electrolyte

LiPF ₆Be dissolved among EC+ γ-BL+DEC (volume ratio 51: 29: 20), make its concentration that reaches 1.75mol/l, this is added VC 2.5wt%, the modulation electrolyte for lithium secondary batteries.In aforementioned electrolyte 96wt%, mix mean molecule quantity and be 7,500～9,000 TA3wt% and mean molecule quantity and be 200～300 GX 1.0wt%.And then, adding BPN 150ppm as polymerization initiator, BPP 150ppm and butyric acid 500ppm obtain precursor solution.

D) assembling of battery

Make battery by the method identical with embodiment 2.

Embodiment 15

Make the battery of embodiment 15 by following operation.

A) making of negative pole

Repeat and embodiment 3 identical operations, make negative pole.

B) Zheng Ji making

Repeat and embodiment 1 identical operations, make anodal.

C) modulation of the precursor solution of gel electrolyte

LiBF ₄Be dissolved among EC+ γ-BL (volume ratio 35: 65), make its concentration that reaches 1.5mol/l, the modulation electrolyte for lithium secondary batteries.In aforementioned electrolyte 96wt%, mix mean molecule quantity and be 7,500～9,000 TA 3wt% and mean molecule quantity and be 200～300 GX 1.0wt%.And then, adding BPN 150ppm as polymerization initiator, BPP 150ppm and butyric acid 500ppm obtain precursor solution.

D) assembling of battery

Make battery by the method identical with embodiment 2.

Embodiment 16

Make the battery of embodiment 16 by following operation.

A) making of negative pole

Repeat and embodiment 2 identical operations, make negative pole.

B) Zheng Ji making

Repeat and embodiment 1 identical operations, make anodal.

C) modulation of the precursor solution of gel electrolyte

LiBF ₄Be dissolved among EC+ γ-BL+MEC (volume ratio 25: 55: 20), make its concentration that reaches 1.8mol/l, this is added VC 3wt%, the modulation electrolyte for lithium secondary batteries.In aforementioned electrolyte 96wt%, mix mean molecule quantity and be 7,500～9,000 TA 3wt% and mean molecule quantity and be 200～300 GX 1.0wt%.And then, add as the peroxidating carbonic acid two in the percarbonic acid class of polymerization initiator (4-tert-butyl group hexamethylene) ester 500ppm and butyric acid 500ppm, obtain precursor solution.

D) assembling of battery

Make battery by the method identical with embodiment 2.Embodiment 17

Make the battery of embodiment 17 by following operation.

A) making of negative pole

Repeat and embodiment 3 identical operations, make negative pole.

B) Zheng Ji making

Repeat and embodiment 1 identical operations, make anodal.

C) modulation of the precursor solution of gel electrolyte

LiBF ₄Be dissolved among EC+ γ-BL+MEC (volume ratio 25: 55: 20), make its concentration that reaches 1.8mol/l, this is added VC 3wt%, the modulation electrolyte for lithium secondary batteries.In aforementioned electrolyte 96wt%, mix mean molecule quantity and be 7,500～9,000 TA 3wt% and mean molecule quantity and be 200～300 GX 1.0wt%.And then, add as meta-methoxy benzoyl 500ppm and butyric acid 250ppm in the peroxidating two acyl classes excessively of polymerization initiator, obtain precursor solution.

D) assembling of battery

Make battery by the method identical with embodiment 2.

Embodiment 18

Make the battery of embodiment 18 by following operation.

A) making of negative pole

Except negative electrode active being changed into Delanium (KS-25), it is 100 weight portions that the composition of negative pole makes material with carbon element into, and PVdF is outside 9 weight portions, makes negative pole by the method identical with embodiment 1.

B) Zheng Ji making

Repeat and embodiment 1 identical operations, make anodal.

C) modulation of the precursor solution of gel electrolyte

LiBF ₄Be dissolved among EC+ γ-BL+MEC (volume ratio 25: 55: 20), make its concentration that reaches 1.8mol/l, this is added VC 3wt%, the modulation electrolyte for lithium secondary batteries.In aforementioned electrolyte 97wt%, mix mean molecule quantity and be 7,500～9,000 TA 2.4wt% and mean molecule quantity and be 200～300 GX 0.6wt%.And then, adding BPN 150ppm as polymerization initiator, BPP 150ppm and butyric acid 103ppm obtain precursor solution.

D) assembling of battery

Make battery by the method identical with embodiment 2.

Embodiment 19

Make the battery of embodiment 19 by following operation.

A) making of negative pole

Except negative electrode active is changed into native graphite, it is 100 weight portions that the composition of negative pole makes material with carbon element into, and PVdF is outside 9 weight portions, makes negative pole by the method identical with embodiment 1.

B) Zheng Ji making

Repeat and embodiment 1 identical operations, make anodal.

C) modulation of the precursor solution of gel electrolyte

LiBF ₄Be dissolved among EC+ γ-BL+DEC (volume ratio 30: 50: 20), make its concentration that reaches 1.8mol/l, this is added VC 3wt%, the modulation electrolyte for lithium secondary batteries.In aforementioned electrolyte 97wt%, mix mean molecule quantity and be 7,500～9,000 TA 2.4wt% and mean molecule quantity and be 200～300 GX 0.6wt%.And then, adding BPN 150ppm as polymerization initiator, BPP 150ppm and butyric acid 102ppm obtain precursor solution.

D) assembling of battery

Make battery by the method identical with embodiment 2.Comparative example 1

Make the battery of comparative example 1 by following operation.

A) making of negative pole

Make negative pole by the method identical with embodiment 3.

B) Zheng Ji making

Repeat and embodiment 1 identical operations, make anodal.

C) modulation of the precursor solution of gel electrolyte

LiBF ₄Be dissolved among EC+ γ-BL+DEC (volume ratio 25: 55: 20), make its concentration that reaches 1.8mol/l, this is added VC 3wt%, the modulation electrolyte for lithium secondary batteries.In aforementioned electrolyte 97wt%, mix mean molecule quantity and be 7,500～9,000 TA 2.4wt% and mean molecule quantity and be 200～300 GX 2.5wt%.And then, add BPN 150ppm as polymerization initiator, obtain precursor solution.

D) assembling of battery

Make battery by the method identical with embodiment 3.Comparative example 2

Make the battery of comparative example 2 by following operation.

A) making of negative pole

Make negative pole by the method identical with embodiment 2.

B) Zheng Ji making

Repeat and embodiment 1 identical operations, make anodal.

C) modulation of the precursor solution of gel electrolyte

LiBF ₄Be dissolved among the EC+MEC (volume ratio 30: 70), make its concentration that reaches 1.8mol/l, this is added VC 3wt%, the modulation electrolyte for lithium secondary batteries.In aforementioned electrolyte 96wt%, mix mean molecule quantity and be 7,500～9,000 TA 3wt% and mean molecule quantity and be 200～300 GX 1.0wt%.And then, add BPN150ppm as polymerization initiator, obtain precursor solution.

D) assembling of battery

Make battery by the method identical with embodiment 3.Comparative example 3

Make the battery of comparative example 3 by following operation.

A) making of negative pole

Make negative pole by the method identical with embodiment 3.

B) Zheng Ji making

Repeat and embodiment 1 identical operations, make anodal.

C) modulation of the precursor solution of gel electrolyte

Except the addition of butyric acid is changed into the 603ppm, by the method modulation precursor solution identical with embodiment 3.

D) assembling of battery

Make battery by the method identical with embodiment 3.Comparative example 4

Make the battery of comparative example 4 by following operation.

A) making of negative pole

Repeat and embodiment 3 same operation, make negative pole.

B) Zheng Ji making

Repeat and embodiment 1 identical operations, make anodal.

C) modulation of the precursor solution of gel electrolyte

Except the addition of butyric acid is changed into the 0ppm, by the method modulation precursor solution identical with embodiment 12.

D) assembling of battery

Make battery by the method identical with embodiment 2.Estimate

(1) the butyric acid content in the gel electrolyte

The battery of making from embodiment 1～19 and comparative example 1～3 carries out solvent extraction with gel electrolyte, tries to achieve the butyric acid content in the extract.Specifically, flood gel electrolyte in THF, the extraction of carrying out after the ultrasonic Treatment more than 72 hours is handled.Filter aforementioned gained extract, utilize the amount of the quantitative butyric acid of gas-chromatography, through type 3 is tried to achieve butyric acid content.Its result is shown in table 1～5.

(2) the capacity sustainment rate of battery

Battery with making in embodiment 1～19 and the comparative example 1～3 charges to cell voltage with certain current value 0.2C and reaches 4.2V, reaches after the 4.2V to charge to total charging interval with certain voltage and reach 12 hours.Be discharged to cell voltage with certain current value and reach 2.75V.In order to study the heavy-current discharge characteristic, promptly part throttle characteristics has been measured the capacity sustainment rate (discharge capacity * 100 among the discharge capacity/0.2C the in=2C discharge) when 20 ℃ 2C discharge.

In order to study low-temperature characteristics, decide after electric current and 4.2V decide to carry out under the voltage charging in 12 hours at 20 ℃ 0.2C, measured capacity sustainment rate when-20 ℃ 0.2C discharge (=-20 ℃ discharge capacities/in 20 ℃ discharge capacities * 100).In order to study charge, repetition is decided electric current and 4.2V decides to carry out under the voltage charging in 12 hours at 20 ℃ 0.2C, with the cycle that 0.2C decides discharge under the electric current, measured the capacity sustainment rate (discharge capacity * 100 in the discharge capacity in=the 300 cycle/the 1st cycle) in the 300th cycle.

And cell evaluation all carries out in clean control box under inert gas atmosphere.

In order to study the effect of butyric acid content, addition, the butyric acid content in the gel electrolyte and the various characteristics of battery of butyric acid in the battery capacity of expression embodiment 1～10 and comparative example 1～3, the precursor solution in table 1.And the gel electrolyte that uses in comparative example 1～2 is that aforementioned spy opens the disclosed gel electrolyte that does not contain butyric acid in the 2001-210380 communique.

Table 1

	Capacity (Ah)	The addition of butyric acid (ppm) in the precursor solution	The content of butyric acid (ppm) in the gel	Capacity sustainment rate (%) during the 2C discharge	Capacity sustainment rate (%) during-20 ℃ of discharges	The capacity sustainment rate (%) in the 300th cycle
							Embodiment 1	????0.79	????15	????12	????80	????80	????75
Embodiment 2	????0.80	????51	????48	????84	????83	????79
							Embodiment 3	????0.81	????102	????97	????86	????86	????82
Embodiment 4	????0.81	????254	????247	????86	????87	????83
							Embodiment 5	????0.80	????452	????445	????84	????83	????81
Embodiment 6	????0.81	????503	????496	????81	????80	????77
							Embodiment 7	????0.77	????9	????5	????76	????69	????68
Embodiment 8	????0.79	????13	????9	????80	????78	????72
							Embodiment 9	????0.80	????511	????506	????81	????78	????75
Embodiment 10	????0.80	????550	????544	????80	????77	????72
							Comparative example 1	????0.80	????0	????0	????68	????66	????62
Comparative example 2	????0.80	????0	????0	????71	????62	????63
							Comparative example 3	????0.79	????610	????603	????70	????65	????60

As can be seen from Table 1, has butyric acid content and is the secondary cell of embodiment 1～6 of the gel electrolyte of 10～500ppm, the capacity sustainment rate that has when satisfying the 2C discharge is more than 80%, capacity sustainment rate during-20 ℃ of discharges is more than 80%, and the capacity sustainment rate in the 300th cycle is the effect of 70% above characteristic.

In addition, the secondary cell of embodiment 7～10 is compared also with the comparative example 1 and 2 that does not add butyric acid and is improved.Embodiment 7 and 8, its butyric acid content be less than 10ppm, and precursor solution is fully in permeable barrier and the electrode, crosslinked after, in gel electrolyte, can not guarantee good ionic conductivity, so can infer the characteristic that can not get embodiment 1～6.And then, can think that also the effect of the compatibility that improves electrode active material and gel electrolyte is also insufficient.

On the other hand, embodiment 9 and 10, its butyric acid content is higher than 500ppm, compares with 2 with comparative example 1 and has obtained certain improvement, but when surpassing 600ppm as comparative example 3 butyric acid content, can not get additive effect.Though do not exist precursor solution to infiltrate the problem of dividing plate and electrode, superfluous butyric acid produces side reaction when discharging and recharging reaction, cause discharging and recharging effect and descend, cycle characteristics reduces.And then, in comparative example 3, become significantly, also can't see effect even contain butyric acid.

Then, in order to study the formation of macromonomer, expression embodiment 11 and 12 in table 2, and the battery capacity of comparative example 4 and 5, the butyric acid addition in the precursor solution, the butyric acid in gel electrolyte contain and the various characteristics of battery.

Table 2

	Capacity (Ah)	The addition of butyric acid (ppm) in the precursor solution	The content of butyric acid (ppm) in the gel	Capacity sustainment rate (%) during the 2C discharge	Capacity sustainment rate (%) during-20 ℃ of discharges	The capacity sustainment rate (%) in the 300th cycle
							Embodiment 11	????0.80	????100	????93	????72	????64	????64
Embodiment 12	????0.79	????101	????94	????73	????68	????66
							Comparative example 4	????0.80	????0	????0	????58	????54	????42
Comparative example 5	????0.80	????0	????0	????61	????56	????45

As can be seen from Table 2, only use trifunctional group acrylate's embodiment 11 and use the secondary cell of trifunctional group acrylate and bifunctional acrylate's embodiment 12 as macromonomer, not as use the embodiment 1～10 of trifunctional group acrylate and simple function group acrylate as macromonomer as macromonomer.But, to only use trifunctional group acrylate's embodiment 11 and comparative example 4 as macromonomer, to using trifunctional group acrylate and bifunctional acrylate's embodiment 12 and the secondary cell of comparative example 5 to compare as macromonomer, the embodiment 11 and 12 that contains butyric acid in gel electrolyte is better, no matter the formation of macromonomer how, can both improve battery behavior.

In the trifunctional group acrylate of embodiment 11 and comparative example 4, the flexibility of gel electrolyte is insufficient, so along with crosslinked expansion, shrink and to crack or break, when discharging and recharging reaction near electrode the not enough and destruction that produces gel electrolyte of flexibility.Therefore, can think that the various characteristics of battery is bad.Even add the bifunctional acrylate as embodiment 12 and comparative example 5, also have same reason.Thereby the formation of macromonomer also is to realize key factor of the present invention.

Then, in order to study nonaqueous solvents, the battery capacity of expression embodiment 13～15, the butyric acid addition in the precursor solution, the butyric acid content in the gel electrolyte, the various characteristics of battery in table 3.

Table 3

	Capacity (Ah)	The addition of butyric acid (ppm) in the precursor solution	The content of butyric acid (ppm) in the gel	Capacity sustainment rate (%) during the 2C discharge	Capacity sustainment rate (%) during-20 ℃ of discharges	The capacity sustainment rate (%) in the 300th cycle
							Embodiment 13	????0.80	??500	?492	??75	????72	????57
Embodiment 14	????0.80	??500	?493	??69	????52	????74
							Embodiment 15	????0.80	??500	?491	??73	????68	????66

From table 3 also as can be seen, the volume ratio of EC is compared with 2 with comparative example 1 less than 10% embodiment 13, and cycle characteristics is bad, but other battery behaviors all are improved.This is because if EC is few, be difficult to cover the graphite particle surface with compact protective film, so graphite particle and γ-BL produce reaction.Thereby, even in gel electrolyte, contain butyric acid, there is not effect yet, cause cycle characteristics to descend.

The volume ratio of EC surpasses 50% embodiment 14, compares with 2 with comparative example 1, and part throttle characteristics and low-temperature characteristics are bad, but cycle characteristics is improved.This be because EC for a long time the viscosity of precursor solution uprise.Thereby, even contain butyric acid, can not remove the difficulty of soaking into dividing plate and electrode, crosslinked after, in dividing plate and electrode, can not form sufficient gel electrolyte, can not get good battery behavior.And the volume ratio 29% of γ-BL seems lower slightly when improving low-temperature characteristics.

Do not use the embodiment 15 of the 3rd solvent, compare with 2, some raisings are arranged on the whole with comparative example 1.But if do not use the 3rd solvent, the viscosity of precursor solution can uprise, the same with embodiment 14, be difficult to soak in dividing plate and the electrode, in dividing plate and electrode, can not form sufficient gel electrolyte after crosslinked, so can not get the battery behavior good as embodiment 1～6.Thereby the formation of nonaqueous solvents also is to realize key factor of the present invention.

Then, in order to study polymerization initiator, expression embodiment 16 and 17 battery capacity, addition, the butyric acid content in the gel electrolyte and the various characteristics of battery of the butyric acid in the precursor solution in table 4.

Table 4

	Capacity (Ah)	The addition of butyric acid (ppm) in the precursor solution	The content of butyric acid (ppm) in the gel	Capacity sustainment rate (%) during the 2C discharge	Capacity sustainment rate (%) during-20 ℃ of discharges	The capacity sustainment rate (%) in the 300th cycle
							Embodiment 16	??0.80	??250	??241	72	??68	??66
Embodiment 17	??0.80	??250	??242	74	??70	??64

As can be seen from Table 4, use the embodiment 16 of peroxidating carbonic acid two (the 4-tert-butyl group hexamethylene) ester in the percarbonic acid class and the embodiment 17 of the meta-methoxy benzoyl peroxide in the peroxidating two acyl classes as polymerization initiator, with use the secondary cell of the embodiment 1～10 of alkyl super-acid ester class as initator and compare, its whole battery behavior is bad, has obtained certain raising but compare with 2 with comparative example 1.

Irrelevant much at one with 10 hours half life temperatures, why above-mentioned battery behavior shows difference, thinks that one of its reason is the reactive different of negative pole and polymerization initiator.This is because the initial charge of the secondary cell of embodiment 1～6 is compared with 17 secondary cell with embodiment 16, demonstrates high about 10 percentage points good efficiencies.That is, we can say the reactive low of alkyl super-acid ester class and negative pole.Thereby the selection of polymerization initiator also is to realize key factor of the present invention.

Then, in order to study the material with carbon element of negative pole, in table 5, represent to use the embodiment 18 of the material with carbon element that on the surface of graphite particle, does not adhere to amorphous carbon and 19 battery capacity, addition, the butyric acid content in the gel electrolyte and the various characteristics of battery of the butyric acid in the precursor solution.

Table 5

	Capacity (Ah)	The addition of butyric acid (ppm) in the precursor solution	The content of butyric acid (ppm) in the gel	Capacity sustainment rate (%) during the 2C discharge	Capacity sustainment rate (%) during-20 ℃ of discharges	The capacity sustainment rate (%) in the 300th cycle
							Embodiment 18	??0.80	??103	???92	????74	????69	????67
Embodiment 19	??0.80	??102	???91	????71	????67	????64

As can be seen from Table 5, embodiment 18 compares with the secondary cell of the embodiment 1～10 that uses surperficial non-crystalline graphite as material with carbon element with 19, and its whole battery behavior is bad, has obtained certain raising but compare with 2 with comparative example 1.This be because, the γ-BL that contains in gel electrolyte compares with other solvents, in charging, i.e. reaction easily under electrochemical reduction so produce side reaction with the graphite material of high crystalline, reduces battery behavior.Thereby,, can prevent the cycle characteristics deterioration by using surperficial non-crystalline graphite.

According to above-mentioned situation, in order to improve secondary cell and the manufacture method thereof that electrode is formed coiling shape, concentrate on studies, it found that, owing in the precursor solution of gel electrolyte, contain butyric acid, the precursor solution solvent becomes and infiltrates dividing plate and electrode, particularly negative pole easily, thus the manufacturing process that has improved secondary cell.And then, in gel electrolyte,, can improve part throttle characteristics, low-temperature characteristics, and can prevent the deterioration of cycle characteristics if contain butyric acid.The invention effect

According to the present invention, by contain butyric acid in the precursor solution of gel electrolyte, precursor solution can infiltrate in dividing plate and the electrode easily, can improve manufacturing process.And then, in gel electrolyte, there is butyric acid, part throttle characteristics, low-temperature characteristics can be improved, and the deterioration of cycle characteristics can be prevented.Therefore, the present invention is significant industrial.

Claims (10)

1. gel electrolyte secondary battery, it is characterized in that, by positive pole that contains the active material that can insert/break away from lithium ion and negative pole, and the gel electrolyte that is arranged between positive pole and the negative pole constitutes, and contains the butyric acid that concentration is 5～550ppm in this gel electrolyte.

2. gel electrolyte secondary battery according to claim 1, described gel electrolyte is made of the crosslinked body of the macromolecule that contains lithium salts, nonaqueous solvents and butyric acid, macromolecule be included in PO/EO=0～5 of containing oxirane (EO) unit or expoxy propane (PO) unit in its chain at least the trifunctional group acrylate polymer or copolymer and contain the EO unit or the polymer or the copolymer of the simple function group acrylate of PO/EO=0～5 of PO unit.

3. gel electrolyte secondary battery according to claim 2, described nonaqueous solvents contains one or more solvents that are selected from ethylene carbonate, gamma-butyrolacton, diethyl carbonate, methyl ethyl carbonate, vinylene carbonate, and contains ethylene carbonate with volume ratio 10～50%.

4. gel electrolyte secondary battery according to claim 1, the active material of described negative pole is for adhering to the graphite particle of amorphous carbon from the teeth outwards.

5. gel electrolyte secondary battery according to claim 1, described butyric acid are the mixture of n-butyric acie, isobutyric acid or these materials.

6. gel electrolyte secondary battery according to claim 2, relative nonaqueous solvents contains the lithium salts in the described gel electrolyte of 0.8～2.5mol/l ratio.

7. gel electrolyte secondary battery according to claim 4, the described graphite particle that adheres to amorphous carbon from the teeth outwards has 1～5m ²The per surface area of/g.

8. the manufacture method of a gel electrolyte secondary battery, this battery is by positive pole that contains the active material that can insert/break away from lithium ion and negative pole, and the gel electrolyte that is arranged between positive pole and the negative pole constitutes, it is characterized in that, under the existence condition of butyric acid, to carry out crosslinked as the macromolecule of the raw material of gel electrolyte and after making the gel electrolysis, so that make gel electrolyte contain the butyric acid that concentration is 5～550ppm.

9. manufacture method according to claim 8, described gel electrolyte, by containing trifunctional group acrylate's the polymer or the copolymer of PO/EO=0～5 of oxirane (EO) unit or expoxy propane (PO) unit in the macromolecular chain at least, with the polymer of the simple function group acrylate of PO/EO=0～5 of containing EO unit or PO unit or copolymer under the existence condition that contains the nonaqueous solvents of lithium salts, polymerization initiator, butyric acid, carry out crosslinked and make.

10. manufacture method according to claim 9, described polymerization initiator are one or more polymerization initiators that are selected from new peroxide tert-butyl caprate, the own ester of peroxidating valeric acid uncle, the peroxidating valeric acid tert-butyl ester.