CN106784712B - Positive electrode and preparation method thereof, positive plate and lithium-sulfur cell - Google Patents
Positive electrode and preparation method thereof, positive plate and lithium-sulfur cell Download PDFInfo
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- CN106784712B CN106784712B CN201611236693.XA CN201611236693A CN106784712B CN 106784712 B CN106784712 B CN 106784712B CN 201611236693 A CN201611236693 A CN 201611236693A CN 106784712 B CN106784712 B CN 106784712B
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Abstract
The present invention provides a kind of lithium sulfur battery anode material and preparation method thereof, positive plate and lithium-sulfur cell, which includes dedoping polyaniline.The preparation method of the positive electrode is that (1) prepares dedoping polyaniline；(2) dedoping polyaniline solutions are prepared；(3) positive electrode is prepared.The positive plate includes collector and the active layer in conjunction with collection liquid surface, and the active layer contains above-mentioned positive electrode.The lithium-sulfur cell includes above-mentioned positive plate.The positive electrode produces new electrochemical kinetics behavior in charge and discharge process, can inhibit shuttle effect and stable structure.Include the positive electrode the active substance gram volume of positive plate is higher, the molten mistake of active material is less and the advantages that stable structure, the specific capacity and cycle life of the lithium-sulfur cell comprising the positive plate are accordingly greatly improved.
Description
Technical field
The invention belongs to battery material technical field more particularly to a kind of positive electrode and preparation method thereof, positive plate and
Lithium-sulfur cell.
Background technique
Lithium-sulfur cell refers to that using lithium metal as cathode, elemental sulfur is the lithium ion secondary of new generation electricity of positive active material
Pond.Lithium metal has higher energy density and operating voltage, the oxygen of element sulphur as the lithium metal battery that cathode assembles
Changing number can from -2 to+6, it is assumed that each sulphur atom electron transfer number is 2, utilizes Li2Inverible transform between S and S, theoretical ratio
Capacity is 1672mAh/g, is calculated by average voltage 2.1V, theoretical energy density 2600Wh/kg.Lithium-sulphur combination is all
The highest solid state electrode combination of energy density in known chemistry bilateral system.
Although lithium-sulfur cell has the above advantages compared with conventional lithium ion battery, there are still active material utilizations
The problems such as low, poor circulation, coulombic efficiency are low, self-discharge rate is high, the paces for having delayed it practical.Lithium-sulfur cell discharged
Journey generates the intermediate product S for being soluble in organic electrolyten 2-(4≤n≤8).Part polysulfide ion is acted in electric field and concentration gradient
Under move out sulphur anode, spread and react to lithium anode, lead to metal lithium electrode surface corrosion passivation and positive-active
The loss of substance reduces the utilization efficiency of battery and cyclical stability.
In recent years, a large amount of research has been carried out in terms of the sulphur anode of lithium-sulfur cell, mainly abundant by using duct, knot
The novel carbon material of structure, electric conductivity excellent conducting polymer and nano metal oxide materials, Lai Tigao positive conductive
Performance improves anode structure, inhibits polysulfide dissolution, and the performance of Li-S battery obtains significant raising.Wherein, doped polyaniline
Modified sulphur anode is one of research direction.
The doping way of polyaniline includes protonic acid doping, ion implantation doping and redox doping etc..Due to
The polyaniline of protonic acid doping have raw material be easy to get, be low in cost, is convieniently synthesized, it is easy film forming, stability is good, conductivity is higher and
The advantages that capable of carrying out Reversible redox reaction between different oxidation state and highdensity charge can be stored, to become people
The emphasis studied.At present applied to the principle of the polyaniline-modified sulphur anode of protonic acid doping of field of batteries mainly using poly-
The electron conduction of aniline and the conductive cladding shell of formation, inhibit polysulfide lithium to spread into organic electrolyte, final improvement lithium sulphur
The performance of battery.But since polyaniline shell mechanical strength itself is poor, during battery charging and discharging, all it is difficult according to reason
The shell structurre model thought is run, even if the dissolution of polysulfide lithium can obtain alleviation to a certain extent, cannot still have been accomplished
Full control.During charging, when the polysulfide lithium departing from anode structure is again to when spreading inside anode, this optimization is set
The anode structure of meter will become physical barrier barrier, and react on the polysulfide ion S of dissolutionn 2-(4≤n≤8), this is also to lead
Electric polymer PAn coats drawback present in sulphur anode.Further, since conductive polyaniline (i.e. protonic acid doping polyaniline) is
Acid, the corrosion that will cause aluminium collector is used as additive.Therefore its technical effect is limited, and according to this effect
The lithium-sulfur cell of Mechanism Design necessarily affects its function and effect once local failure occurs for conducting polymer shell.
Summary of the invention
The technical problem to be solved by the present invention is to overcome the deficiencies in the prior art, providing a kind of can inhibit shuttle effect and knot
The stable positive electrode of structure, correspondingly provides the preparation method of the positive electrode, in addition, also providing a kind of active material gram volume
The molten mistake of higher, active material less and the positive plate comprising the positive electrode of stable structure, also provides a kind of specific capacity and circulation
Service life high lithium-sulfur cell.
In order to solve the above technical problems, the invention adopts the following technical scheme:
A kind of positive electrode, the positive electrode include dedoping polyaniline.
Above-mentioned positive electrode, it is preferred that the dedoping polyaniline is that the polyaniline of protonic acid doping is adulterated through depickling
After formed.
Above-mentioned positive electrode, it is preferred that the positive electrode is dedoping polyaniline-sulphur-carbon complex.
In above-mentioned dedoping polyaniline-sulphur-carbon complex, dedoping polyaniline is dispersed in carbon skeleton with molecular level
On.
The inventive concept total as one, the present invention also provides a kind of preparation methods of positive electrode, comprising the following steps:
(1) it prepares dedoping polyaniline: the polyaniline of protonic acid doping is added in alkaline solution, neutralize anti-
It answers, obtains dedoping polyaniline；
(2) dedoping polyaniline solutions are prepared: the resulting dedoping polyaniline of step (1) is dissolved in organic solvent,
Obtain dedoping polyaniline solutions；
(3) it prepares positive electrode: the resulting dedoping polyaniline solutions of step (2) is mixed with sulphur-carbon complex, it is dry
Ball milling afterwards obtains positive electrode.
The preparation method of above-mentioned positive electrode, it is preferred that in the step (1), the alkaline solution is ammonium hydroxide, pH value
It is 9~12, the polyaniline of the acid doping and the mass ratio of ammonium hydroxide are 0.5: 10~100.
The preparation method of above-mentioned positive electrode, it is preferred that in the step (2), the organic solvent is acetone, fourth
One of ketone, N-Methyl pyrrolidone, N-METHYLFORMAMIDE, glycol dimethyl ether and ethylene carbonate are a variety of, described de-
The mass ratio of doped polyaniline and organic solvent is 0.1: 10~50.
The preparation method of above-mentioned positive electrode, it is preferred that in the step (3), the dedoping polyaniline solutions with
Sulphur-carbon complex mass ratio is 2~20: 0.32.
Further, the preparation method of above-mentioned positive electrode, in the step (1), the polyphenyl of the protonic acid doping
Amine the preparation method comprises the following steps: aniline monomer is added in acid solution under protective atmosphere, then water soluble starter is added dropwise, polymerize anti-
It answers, generates the polyaniline of protonic acid doping.
Water soluble starter is (NH4)2S2O8The solution, (NH4)2S2O8In, (NH4)2S2O8With the mass ratio of water be 1~
5:50；Time for adding is 0.1h~5h, carries out polymerization reaction after being added dropwise at 0~30 DEG C, and the reaction time is 0.5~5h,
It filters, washs after standing, it is dry, obtain the polyaniline of protonic acid doping.
The polyaniline yield of resulting protonic acid doping is 60%~105%, 0.1 S/cm of conductivity~10S/cm.It is mixed by de-
Mass Calculation after miscellaneous, yield are 50%~85%.It is available Bu Tong conductive with oxidizer by control time for adding
The polyaniline of the protonic acid doping of rate and yield.
Further, the preparation method of above-mentioned positive electrode, in the step (3), the preparation of the sulphur-carbon complex
Method are as follows: by Na2S and Na2SO3It is dissolved in water, adds conductive carbon, mixed in hydrochloric acid is added after being dispersed with stirring, is filtered, is washed, is done
It is dry, obtain carbon/sulfur compound.
Wherein, the conductive carbon includes acetylene black, superconduction carbon or carbon nanotube.
The inventive concept total as one, the present invention also provides a kind of positive plates, including collector and and collection liquid surface
In conjunction with active layer, the active layer contains positive electrode, and the positive electrode is above-mentioned positive electrode or above-mentioned anode
Positive electrode prepared by the preparation method of material.
Further, above-mentioned positive plate, the active layer also contain conductive agent and adhesive.
Wherein, the mass ratio of the positive electrode, conductive agent and adhesive is 85: 4: 11.
The conductive agent is preferably carbon-based conductive agent, such as conductive carbon black, acetylene black or graphite powder；Described adhesive is preferably
Kynoar.
The positive plate the preparation method comprises the following steps: by positive electrode, conductive agent, adhesive and auxiliary agent mix after ball milling 4h, obtain
To mixed slurry；Gained mixed slurry is coated on to two surfaces of collector (such as aluminium foil or aluminium net), 60 DEG C of vacuum drying
12h obtains positive plate after tailoring.
The positive plate is preferably dimensioned to be long 10cm, width 5cm.Positive S carrying capacity is 2 mg/cm2~10mg/cm2。
The inventive concept total as one, the present invention also provides a kind of lithium-sulfur cell, the lithium-sulfur cell includes above-mentioned
Positive plate.
Above-mentioned lithium-sulfur cell, it is preferred that the charge and discharge system of the lithium-sulfur cell are as follows: battery with 0.1C multiplying power discharging extremely
2.3V~1.8V shelves 0.5h, then charges to 2.5V~3.6V with 0.1C multiplying power, shelves 0.5h, hereafter the lithium-sulfur cell exists
Charge and discharge cycles are carried out between 1.5V~3.6V.
Above-mentioned lithium-sulfur cell, more preferably, the charge and discharge system of the lithium-sulfur cell are as follows: battery with 0.1C multiplying power discharging extremely
2.3V~2.0V shelves 0.5h, then charges to 2.5V~3.6V with 0.1C multiplying power, shelves 0.5h, hereafter the lithium-sulfur cell exists
Charge and discharge cycles are carried out between 1.5V~3.6V.
Further, above-mentioned lithium-sulfur cell also includes cathode of lithium, positive electrolyte film and organic electrolyte.
The cathode of lithium contains the negative electrode active material of lithium metal or lithium alloy；Preferably, the cathode of lithium, which also contains, leads
Electric material and bonding agent.
The organic electrolyte includes lithium salts, nonaqueous solvents and shuttle inhibitor, and the lithium salts is selected from lithium hexafluoro phosphate
(LiPF6), LiBF4 (LiBF4), hexafluoroarsenate lithium (LiAsF6), lithium perchlorate (LiClO4), trifluoromethanesulp-onyl -onyl imide
Lithium (LiN (CF3SO2)2), trifluoromethyl sulfonic acid lithium (LiSO3CF3), lithium nitrate, at least one of the polysulfide lithium of different valence state.
The nonaqueous solvents includes acetonitrile, hexamethylene, cyclohexanone, isopropanol, tetrahydrofuran, 2- methyltetrahydrofuran, ethylene carbonate
Ester, propene carbonate, butylene, dimethyl carbonate, diethyl carbonate, methyl ethyl carbonate, methyl propyl carbonate, formic acid first
Ester, Ethyl formate, methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, ethyl butyrate, dimethoxy second
Alkane, 1,3- dioxolane, diethylene glycol dimethyl ether (dimethoxy-ethyl ether), triglyme, tetraethylene glycol dimethyl ether, diethyl two
At least one of diethylene glycol dimethyl ether, sulfolane, two methylene sulfones, dimethyl sulfone.By adjusting nonaqueous solvents in organic electrolyte
Type, concentration can adjust the ionic conduction characteristic of dielectric film in a certain range, influence the conductivity of dielectric film, and mention
The cycle performance of high lithium-sulfur cell.The aforementioned nonaqueous solvents being preferably added to has certain activation, electrolyte to dielectric film
After organic solvent in film meeting Electolyte-absorptive reaches certain balance, played in lithium-sulfur cell with higher ionic conductivity good
Good conducting lithium ions simultaneously inhibit anion and organic molecule in the mutual diffusion mobility of positive and negative interpolar.
Compared with the prior art, the advantages of the present invention are as follows:
1, positive electrode of the invention includes dedoping polyaniline, using sending out in the dedoping polyaniline charge and discharge process
Raw redox doping can reduce S in electrolyten 2-Concentration, specifically: the dedoping polyaniline charge and discharge process will send out
Raw electrochemical oxidation and reduction, charging process dedoping polyaniline lose electronics, while the anion in Electolyte-absorptive is to protect
Charge balance is held, that is, anion doped process occurs；Discharge process polymer obtains electronics, while anion dedoping occurs.
Using the reversible doping process in dedoping polyaniline electrode reaction process, in lithium-sulfur cell by ionic adsorption with exchange spy
Property constraint and release Sn 2-(8 >=n >=4) reduce S in electrolyten 2-Concentration, reduce its residence time in the electrolytic solution, it is real
Now the concentration dynamic of polysulfide ion in electrolyte is controlled, to inhibit shuttle effect, improve lithium-sulfur cell cycle performance and
Coulombic efficiency.
2, further, dedoping polyaniline of the invention is formed after dedoping by the polyaniline of protonic acid doping, tool
Have solubility, can be scattered in positive electrode with molecular level, be conducive to electrode process it is anion doped/dedoping process
Progress.
3, the preparation method of positive electrode of the invention, by dedoping polyaniline be dissolved in after organic solvent again with sulphur-carbon
Compound mixing, obtains dedoping polyaniline-sulphur-carbon complex, dedoping polyaniline is dispersed in carbonaceous conductive bone with molecular level
On frame, be conducive to electrode process it is anion doped/progress of dedoping process.In addition, the positive electrode preparation process technique letter
It is single, it is low in cost, it is easy to accomplish industrialized production.
4, positive plate of the invention due to contain the positive electrode of polyaniline containing dedoping of the invention, in charge and discharge
In the process, the active material of the positive plate is molten loses few, stable structure.
5, lithium-sulfur cell of the invention due to contain positive plate of the invention, then the lithium-sulfur cell in charge and discharge process,
Active material gram volume is few compared with high, active material molten mistake, thus has excellent cycle performance.
Detailed description of the invention
Fig. 1 is the cycle performance comparison diagram of the lithium-sulfur cell of the embodiment of the present invention 1 and the lithium-sulfur cell of comparative example 1.
Fig. 2 is the cyclic voltammetric comparison diagram of the lithium-sulfur cell of the embodiment of the present invention 1 and the lithium-sulfur cell of comparative example 1.
Fig. 3 is the cycle performance comparison diagram of the lithium-sulfur cell of the embodiment of the present invention 1 and the lithium-sulfur cell of comparative example 2.
Fig. 4 is the cyclic voltammetric comparison diagram of the lithium-sulfur cell of the embodiment of the present invention 1 and the lithium-sulfur cell of comparative example 2.
Fig. 5 is the discharge curve for the first time of the lithium-sulfur cell of the embodiment of the present invention 1 and the lithium-sulfur cell of comparative example 2.
Specific embodiment
Below in conjunction with Figure of description and specific preferred embodiment, the invention will be further described, but not therefore and
It limits the scope of the invention.
Embodiment 1:
A kind of positive electrode of the invention is dedoping polyaniline-sulphur-carbon complex, the dedoping polyaniline-sulphur-carbon
Dedoping polyaniline in compound is that the polyaniline of protonic acid doping is formed after depickling is adulterated.Dedoping polyaniline has can
Dissolubility can be dispersed on carbon skeleton with molecular level, be conducive to electrode process it is anion doped/progress of dedoping process；Sulphur
It is dispersed in carbon skeleton surface.
The preparation method of the positive electrode of above-mentioned the present embodiment, comprising the following steps:
(1) polyaniline of protonic acid doping is prepared:
(1.1) aniline monomer is evaporated under reduced pressure and is placed in refrigerator after purification for use.The three-necked flask of 250 ml is taken,
The deionized water of 60ml is added, 5ml concentrated hydrochloric acid is added thereto, then flask is placed in ice-water bath, the case where being stirred continuously
Under be passed through 30 min of high-purity Ar gas, then be added 1g aniline monomer, continue to be passed through pure Ar gas and stir；
(1.2) 3.2g (NH is weighed4)2S2O8, it is dissolved in 40ml deionized water, is then slowly added dropwise into flask
(NH4)2S2O8Solution after being added dropwise, reacts 2h in 5 DEG C of ice-water baths；Then three-necked flask is taken out from ice bath, in room
After the lower placement 12h of temperature, with filtered on buchner funnel, filter residue is obtained, then filter residue is cleaned into precipitating with deionized water repeatedly, until filtrate
PH=7；The polyaniline of protonic acid doping is obtained, by vacuum at the polyaniline of the protonic acid doping in a vacuum drying oven 60 DEG C
Dry 12 h.
(2) it prepares dedoping polyaniline: step (1) being weighed to the polyaniline 0.5g of the protonic acid doping after drying, through grinding
It is put into beaker after mill, the ammonium hydroxide 25g that pH value is 11 is added, magnetic agitation under air-proof condition carries out depickling doping reaction 2h, washing
After drying, the dedoping polyaniline of black is obtained.
(3) dedoping polyaniline solutions are prepared: dedoping polyaniline made from step (2) being taken into 0.05g, is added to 10g
It in N-Methyl pyrrolidone solution, is dissolved under magnetic agitation, obtains dedoping polyaniline solutions.
(4) it prepares sulphur-carbon complex: preparing 2.0gNa2S and 1.62g anhydrous Na2SO3100 milliliters of aqueous solution, be added
0.08g acetylene black is dispersed with stirring 10min, and 40g1M hydrochloric acid solution is added, and after stirring 1h, is filtered, washed, dries, obtain sulphur-carbon
Compound.
(5) it prepares positive electrode: taking dedoping polyaniline solutions 6g made from step (3), with sulphur-made from step (4)
Carbon complex is stirred, and ball milling after drying obtains finely dispersed dedoping polyaniline-sulphur-carbon complex.
Positive electrode manufactured in the present embodiment is used for the preparation of positive plate, comprising the following steps:
Dedoping polyaniline-sulphur-carbon complex manufactured in the present embodiment, acetylene black (conductive agent), Kynoar is (viscous
Mixture) and auxiliary agent mixing after ball milling 4h；Wherein, the mass ratio of dedoping polyaniline-sulphur-carbon complex, conductive agent and adhesive
It is 85: 4: 11, obtains mixed slurry；Mixed slurry is dried in vacuo coated on the two-sided of aluminium foil at 60 DEG C using coating machine
12h becomes the active layer in conjunction with collection liquid surface after mixed slurry is dry, tailor as the positive plate of 10cm long, 5cm wide, just
Pole S carrying capacity is 6mg/cm2。
Positive plate manufactured in the present embodiment is assembled on lithium-sulfur cell, detailed process are as follows: positive plate, Celgard is more
Hole diaphragm and lithium foil are prepared into monolithic battery core in glove box, and lithium foil used adds organic electrolyte, very with a thickness of 100 μm
It is placed for 24 hours after sky encapsulation, obtains lithium-sulfur cell.In organic electrolyte, nonaqueous solvents is glycol dimethyl ether (DME) and 1,3- bis-
The mixed solvent of oxygen pentane (DOL) composition, lithium salts are lithium nitrate, and the concentration of lithium nitrate is 0.2M.
Lithium-sulfur cell manufactured in the present embodiment is subjected to charge and discharge and cyclic voltammetry.Battery with 0.1C multiplying power discharging extremely
2.0V shelves 0.5h, charges to 3.2V with 0.1C multiplying power, shelves 0.5h, and charging process polyaniline is oxidized, and loses electronics, together
When doped solution middle and high concentration polysulfide ion, battery carries out charge and discharge cycles between 1.5 ~ 3.2V thereafter.
Comparative example 1:
The positive electrode of a kind of comparative example is protonic acid doping polyaniline-sulphur-carbon complex.
The preparation method of the positive electrode of above-mentioned comparative example, comprising the following steps:
(1) polyaniline of protonic acid doping is prepared:
(1.1) aniline monomer is evaporated under reduced pressure and is placed in refrigerator after purification for use.The three-necked flask of 250 ml is taken,
The deionized water of 60ml is added, 5ml concentrated hydrochloric acid is added thereto, then flask is placed in ice-water bath, the case where being stirred continuously
Under be passed through 30 min of high-purity Ar gas, then be added 1g aniline monomer, continue to be passed through pure Ar gas and stir；
(1.2) 3.2g (NH is weighed4)2S2O8, it is dissolved in 40ml deionized water, is then slowly added dropwise into flask
(NH4)2S2O8Solution after being added dropwise, reacts 2h in 5 DEG C of ice-water baths；Then three-necked flask is taken out from ice bath, in room
After the lower placement 12h of temperature, with filtered on buchner funnel, filter residue is obtained, then filter residue is cleaned into precipitating with deionized water repeatedly, until filtrate
PH=7；The polyaniline of acid doping is obtained, 12 h will be dried in vacuo at the polyaniline of the acid doping in a vacuum drying oven 60 DEG C.
(2) it prepares sulphur-carbon complex: preparing 2.0gNa2S and 1.62g anhydrous Na2SO3100 milliliters of aqueous solution, be added
0.08g acetylene black is dispersed with stirring 10min, and 40g1M hydrochloric acid solution is added, and after stirring 1h, is filtered, washed, dries, obtain sulphur-carbon
Compound.
(3) it prepares positive electrode: taking the polyaniline 0.03g of protonic acid doping made from step (1), be made with step (2)
Carbon/sulfur compound ball milling, obtain protonic acid doping polyaniline-sulphur-carbon complex.
Positive electrode prepared by this comparative example is used for the preparation of positive plate, comprising the following steps:
By polyaniline-sulphur-carbon complex of protonic acid doping prepared by this comparative example, acetylene black (conductive agent), gather inclined fluorine
Ball milling 4h after ethylene (adhesive) and auxiliary agent mixing；Wherein, polyaniline-sulphur-carbon complex of protonic acid doping, conductive agent and viscous
The mass ratio of mixture is 85: 4: 11, obtains mixed slurry；Using coating machine by mixed slurry coated on the two-sided of aluminium foil, 60
DEG C vacuum drying 12h, become the active layer in conjunction with collection liquid surface after mixed slurry is dry, tailors as 10cm long, 5cm wide
Positive plate, positive S carrying capacity are 6mg/cm2。
Positive plate prepared by this comparative example is assembled on lithium-sulfur cell, detailed process are as follows: positive plate, Celgard is more
Hole diaphragm and lithium foil are prepared into monolithic battery core in glove box, and lithium foil used adds organic electrolyte, very with a thickness of 100 μm
It is placed for 24 hours after sky encapsulation, obtains lithium-sulfur cell.In organic electrolyte, nonaqueous solvents is glycol dimethyl ether (DME) and 1,3- bis-
The mixed solvent of oxygen pentane (DOL) composition, lithium salts are lithium nitrate, and the concentration of lithium nitrate is 0.2M.
Lithium-sulfur cell prepared by this comparative example carries out charge and discharge and cyclic voltammetry.Battery with 0.1C multiplying power discharging extremely
2.0V shelves 0.5h, charges to 3.2V with 0.1C multiplying power, shelves 0.5h, and charging process polyaniline is oxidized, and loses electronics, together
When solution in anion doped solution middle and high concentration polysulfide ion, battery carries out charge and discharge between 1.5 ~ 3.2V and follows thereafter
Ring.After circulation terminates it is observed that protonic acid doping polyaniline-sulphur-carbon complex positive electrode causes one to aluminium collector
Determine the corrosion of degree.
Fig. 1 is the cycle performance comparison diagram of the lithium-sulfur cell of embodiment 1 and the lithium-sulfur cell of comparative example 1, as seen from the figure, this
Compared with comparative example 1, lithium-sulfur cell of the invention has higher specific capacity and better cycle performance for invention.0.2C multiplying power is permanent
When flowing charge and discharge, dedoping polyaniline is dispersed with molecular level, anode composite lithium-sulfur cell specific capacity and circulation prepared therefrom
Performance is all more preferable.
Fig. 2 is the cyclic voltammogram of the lithium-sulfur cell of embodiment 1 and the lithium-sulfur cell of comparative example 1, as seen from the figure, the two
The area ratio of low potential and high potential discharge peak is dramatically different, and comparative example 1 is 3: 1, and the present invention is 1: 1, it is seen that the present invention
Reversible doping dedoping process has occurred in positive electrode in charge and discharge process, produces different from the positive electrode of comparative example 1
Electrochemical kinetics behavior.Specifically: in charge and discharge process electrochemical oxidation and reduction will occur for the dedoping polyaniline, fill
Electric process dedoping polyaniline loses electronics, while the anion in Electolyte-absorptive to be to keep charge balance, that is, occur yin from
Sub- doping process；Discharge process polymer obtains electronics, while anion dedoping occurs, in lithium-sulfur cell discharge process,
High-voltage discharge platform corresponds to S8Gradually it is reduced to long-chain polysulfide lithium Sn 2-The process of (4≤n≤8), low-voltage discharge platform
It is further reduced corresponding to long-chain polysulfide lithium and generates lower valency polysulfide ion S2 2-And S2-Process.High potential electric discharge peak area
Become larger, illustrate sulphur simple substance be changed into long-chain polysulfide lithium process it is more abundant, the utilization rate of sulphur active material is improved, theoretically
The performance of battery will be improved, and by optimization positive electrode and lithium-sulfur cell preparation process, it is more right to be expected to acquisition comprehensive performance
The superior lithium-sulfur cell of ratio 1.In addition, the reversible doping dedoping mistake using dedoping polyaniline in electrode process
Journey fetters by ionic adsorption and commutativity in lithium-sulfur cell and discharges Sn 2-(8 >=n >=4) reduce S in electrolyten 2-'s
Concentration reduces its residence time in the electrolytic solution, the concentration dynamic regulation to polysulfide ion in electrolyte is realized, to inhibit
Shuttle effect improves the cycle performance and coulombic efficiency of lithium-sulfur cell.
Comparative example 2:
The positive electrode of a kind of comparative example is sulphur-carbon complex.
The preparation method of the positive electrode of above-mentioned comparative example, comprising the following steps:
Prepare 2.0gNa2S and 1.62g anhydrous Na2SO3100 milliliters of aqueous solution, be added 0.08g acetylene black, be dispersed with stirring
40g1M hydrochloric acid solution is added in 10min, after stirring 1h, is filtered, washed, dries, obtain sulphur-carbon complex.
Positive electrode prepared by this comparative example is used for the preparation of positive plate, comprising the following steps:
Sulphur-carbon complex, acetylene black (conductive agent), Kynoar (adhesive) and auxiliary agent prepared by this comparative example is mixed
Ball milling 4h after conjunction；Wherein, the mass ratio of sulphur-carbon complex, conductive agent and adhesive is 85: 4: 11, obtains mixed slurry；It uses
Coating machine is by mixed slurry coated on the two-sided of aluminium foil, and in 60 DEG C of vacuum drying 12h, mixed slurry becomes after drying and collector
The active layer that surface combines is tailored as the positive plate of 10cm long, 5cm wide, and positive S carrying capacity is 6mg/cm2。
Positive plate prepared by this comparative example is assembled on lithium-sulfur cell, detailed process are as follows: positive plate, Celgard is more
Hole diaphragm and lithium foil are prepared into monolithic battery core in glove box, and lithium foil used adds organic electrolyte, very with a thickness of 100 μm
It is placed for 24 hours after sky encapsulation, obtains lithium-sulfur cell.In organic electrolyte, nonaqueous solvents is glycol dimethyl ether (DME) and 1,3- bis-
The mixed solvent of oxygen pentane (DOL) composition, lithium salts are lithium nitrate, and the concentration of lithium nitrate is 0.2M.
Lithium-sulfur cell prepared by this comparative example carries out charge and discharge and cyclic voltammetry.Battery with 0.1C multiplying power discharging extremely
2.0V shelves 0.5h, charges to 3.2V with 0.1C multiplying power, shelves 0.5h, and charging process polyaniline is oxidized, and loses electronics, together
When solution in anion doped solution middle and high concentration polysulfide ion, battery carries out charge and discharge between 1.7V~2.8V thereafter
Circulation.
Fig. 3 is the cycle performance comparison diagram of the lithium-sulfur cell of the embodiment of the present invention 1 and the lithium-sulfur cell of comparative example 2, by scheming
It is found that the lithium-sulfur cell relative to comparative example 2, the specific capacity and cycle performance of the lithium-sulfur cell of the present embodiment, which have, significantly to be mentioned
Height, when 0.2C multiplying power constant current charge-discharge, the lithium-sulfur cell of embodiment 1 has higher specific capacity and better cycle performance.
Fig. 4 is the cyclic voltammogram of the lithium-sulfur cell of embodiment 1 and the lithium-sulfur cell of comparative example 2, and comparison diagram 2 is it is found that right
The cyclic voltammogram of ratio 1 and comparative example 2 are completely the same, illustrate that the electrochemical kinetics behavior of the two is consistent.And the present invention is just
Pole material produces the electrochemical kinetics different from the positive electrode of comparative example 1 and comparative example 2 due to containing dedoping polyaniline
Scholarship and moral conduct is that reversible doping dedoping process has occurred in charge and discharge process.High potential electric discharge peak area becomes larger, and illustrates sulphur list
Qualitative change is that the process of long-chain polysulfide lithium is more abundant, in conjunction with Fig. 5 it follows that the utilization rate of sulphur active material is improved, electricity
The performance in pond is improved.Fig. 5 is the song of electric discharge for the first time of the lithium-sulfur cell of the embodiment of the present invention 1 and the lithium-sulfur cell of comparative example 2
Line comparison diagram, it can be seen from the figure that introducing the lithium-sulfur cell of dedoping polyaniline, discharge capacity is significantly improved for the first time, sulphur
Utilization rate obtains raising by a relatively large margin, so that battery performance is more excellent.
The above is only a preferred embodiment of the present invention, protection scope of the present invention is not limited merely to above-mentioned implementation
Example.All technical solutions belonged under thinking of the present invention all belong to the scope of protection of the present invention.It is noted that for the art
Those of ordinary skill for, improvements and modifications without departing from the principle of the present invention, these improvements and modifications are also answered
It is considered as protection scope of the present invention.
Claims (8)
1. a kind of positive electrode, which is characterized in that the positive electrode is dedoping polyaniline-sulphur-carbon complex, and described take off is mixed
Heteromeric aniline is that the polyaniline of protonic acid doping is formed after dedoping, in the dedoping polyaniline-sulphur-carbon complex, is taken off
Doped polyaniline is dispersed on carbon skeleton with molecular level.
2. a kind of preparation method of positive electrode, comprising the following steps:
(1) it prepares dedoping polyaniline: the polyaniline of protonic acid doping is added in alkaline solution, carry out neutralization reaction, obtain
To dedoping polyaniline；
(2) dedoping polyaniline solutions are prepared: the resulting dedoping polyaniline of step (1) being dissolved in organic solvent, is obtained
Dedoping polyaniline solutions；
(3) it prepares positive electrode: the resulting dedoping polyaniline solutions of step (2) is mixed with sulphur-carbon complex, ball after drying
Mill, obtains positive electrode.
3. the preparation method of positive electrode according to claim 2, which is characterized in that in the step (1), the alkalinity
Solution is ammonium hydroxide, and pH value is 9~12, and the polyaniline of the acid doping and the mass ratio of ammonium hydroxide are 0.5: 10~100.
4. the preparation method of positive electrode according to claim 2 or 3, which is characterized in that described in the step (2)
Organic solvent is in acetone, butanone, N-Methyl pyrrolidone, N-METHYLFORMAMIDE, glycol dimethyl ether and ethylene carbonate
One or more, the mass ratio of the dedoping polyaniline and organic solvent is 0.1: 10~50.
5. the preparation method of positive electrode according to claim 4, which is characterized in that in the step (3), described take off is mixed
Heteromeric aniline solution and sulphur-carbon complex mass ratio are 2~20: 0.32.
6. a kind of positive plate, the active layer including collector and in conjunction with collection liquid surface, the active layer contain positive electrode,
It is characterized in that, the positive electrode is positive electrode described in claim 1 or described in any item by claim 2~5
Positive electrode prepared by the preparation method of positive electrode.
7. a kind of lithium-sulfur cell, which is characterized in that the lithium-sulfur cell includes positive plate as claimed in claim 6.
8. lithium-sulfur cell according to claim 7, which is characterized in that the charge and discharge system of the lithium-sulfur cell are as follows: battery
With 0.1C multiplying power discharging to 2.3V~1.8V, 0.5h is shelved, then 2.5V~3.6V is charged to 0.1C multiplying power, shelves 0.5h, this
The lithium-sulfur cell carries out charge and discharge cycles between 1.5V~3.6V afterwards.
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN101630729A (en) * | 2009-04-16 | 2010-01-20 | 华中科技大学 | Composite electrode materials for high power lithium secondary battery and preparation method thereof |
| CN101800131A (en) * | 2010-03-11 | 2010-08-11 | 湘潭大学 | Active carbon-based material and preparation method thereof |
| CN102447113A (en) * | 2011-12-12 | 2012-05-09 | 南开大学 | Lithium battery with polymer-coated sulfur/carbon composite material as anode |
| CN105958011A (en) * | 2011-06-29 | 2016-09-21 | 日东电工株式会社 | Nonaqueous-electrolyte secondary battery and positive-electrode sheet therefor |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN101630729A (en) * | 2009-04-16 | 2010-01-20 | 华中科技大学 | Composite electrode materials for high power lithium secondary battery and preparation method thereof |
| CN101800131A (en) * | 2010-03-11 | 2010-08-11 | 湘潭大学 | Active carbon-based material and preparation method thereof |
| CN105958011A (en) * | 2011-06-29 | 2016-09-21 | 日东电工株式会社 | Nonaqueous-electrolyte secondary battery and positive-electrode sheet therefor |
| CN102447113A (en) * | 2011-12-12 | 2012-05-09 | 南开大学 | Lithium battery with polymer-coated sulfur/carbon composite material as anode |
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