A kind of high working voltage super capacitor and manufacture method thereof
Technical field
The present invention relates to a kind of ultracapacitor and manufacture method thereof, relate in particular to a kind of high working voltage super capacitor and manufacture method thereof that comprises high working voltage electrolyte.
Background technology
Ultracapacitor is a kind of novel environment friendly energy storage device between traditional capacitor and secondary cell that occurs in recent years, it is when keeping the big characteristics of traditional capacitor power density, its static capacity can reach farad level even thousands of farad, therefore also have the higher characteristics of energy density, simultaneously ultracapacitor has also that the speed of discharging and recharging is fast, efficiency for charge-discharge is high, the life-span is long, fail safe is good, advantages of environment protection, is a kind of novel, practical, energy storage device efficiently.
Ultracapacitor can be divided into two classes according to the energy storage principle difference:
(1) interfacial electric double layer principle.Solid electrode is immersed in the electrolyte solution, when applying the decomposition voltage that is lower than solution, can in minimum distance, distribute, arrange with different two alternate electric charges of electrolyte solution at solid electrode, thereby form electric double layer (Electric Double Layer) closely.Energy is stored in the surface of electrode material with electric charge or concentrated electronics, and electronics passes to negative pole by external power from positive pole during charging, and the negative ions in the electrolyte body separately and move to electrode surface simultaneously; Electronics moves to positive pole by load from negative pole during discharge, and negative ions then discharges and mobile returning the electrolyte body from electrode surface.The double electric layer capacitor patent of doing electrode material from Beck in 1954 application active carbon so far, research to the carbon back electrode material for super capacitor has been carried out more than 40 year, it is ripe that technology has been tending towards, concentrates on mainly that preparation has the porous carbon materials of high specific surface area and less internal resistance and carbon-based material carried out aspect such as study on the modification.The carbon-based material that can meet the demands mainly contains after deliberation: active carbon, carbon black, carbon nano-fiber, carbon aerogels, carbon nano-tube, vitreous carbon, network configuration active carbon and some organic carbonizing production etc.
(2) fake capacitance principle.Electrode surface or body in mutually two dimension or accurate two-dimensional space on electroactive material carry out that highly reversible chemisorbed desorption takes place underpotential deposition or redox reaction produces the electric capacity relevant with the electrode charging potential.Electrode material comprises transition metal oxide and conducting polymer composite.
Ultracapacitor all has broad application prospects in a lot of fields:
(1) back-up source.The widest part of supercapacitor applications is the electronic product field at present, mainly is the back-up source that serves as CMOS (complementary metal oxide semiconductors (CMOS)) protection, timer, clock and watch, video tape recorder, mobile phone etc.
The general nominal voltage of ultracapacitor product in the market is 2.3V, and 2.5V and 2.7V surpass 3.3V, and the electrolyte of its ultracapacitor perfusion is alkyl quaternary amine salt (for example tetraethylammonium tetrafluoroborate), and its electrochemical window is 4.0V~4.6V.Therefore ultracapacitor product in the market is not suitable as the memory power supply.
(2) replace power supply.The for example conversion at daytime-night, daytime, solar energy provided power supply and to ultracapacitor charging, then provide power supply by ultracapacitor evening.Typical application has: solar energy wrist-watch, Solar lamp, road sign lamp, bus stop timetable lamp, automobile parking charging lamp and traffic lights etc.
(3) main power source.Discharge lasting several milliseconds of big electric currents to a few minutes by one or several ultracapacitor, after the discharge, ultracapacitor is again by lower powered power source charges.The typical case uses and comprises electronic toy, model airplane etc.
(4) power accessory power supply.Use in parallel with storage battery, ultracapacitor provide power auxiliary, the pulse power of balance power supply system.Digital camera, Digital Video, solar cell device and fuel cell system etc. have been applied at present.The particularly application on electric automobile provides wide space for the development of ultracapacitor.High power for example is provided when automobile starting, acceleration, climbing,, when brake, reclaims and store excess energy with the protection storage battery.
Summary of the invention
The objective of the invention is to solve the low excessively shortcoming of ultracapacitor operating voltage, a kind of high working voltage (ultracapacitor of the cycle performance that 3.0V~3.5V), high-energy-density are become reconciled is provided.
To achieve these goals, technical scheme of the present invention is:
A kind of high working voltage super capacitor comprises: anodal polarizing electrode, negative pole polarizing electrode, porous isolating membrane and electrolyte; Anodal polarizing electrode comprises positive active material, binding agent, conductive agent; The negative pole polarizing electrode comprises negative electrode active material, binding agent, conductive agent; It is characterized in that: described electrolyte is high working voltage electrolyte, and the electrolyte salt chemical general formula of its high working voltage electrolyte is as follows:
Wherein, cation is a quaternary alkylphosphonium salt, is made up of two close ring groups; Two annulus groups can be three-membered rings, four-membered ring, five-membered ring or hexatomic ring; Two annulus groups can be identical groups, also can be different groups; X
-Be BF
4 -, ClO
4 -, PF
6 -
Electrolyte solvent can be ethylene carbonate (EC), propene carbonate (PC) cyclic ester, dimethyl carbonate (DMC), diethyl carbonate (DEC) chain ester, acetonitrile (AN), butyrolactone (GBL) a kind of or their mixed solvent;
Concentration of electrolyte is 0.5~5.0 mol;
Above-mentioned electrolyte has the above electrochemical window of 4.6V.
According to described high working voltage super capacitor, it is characterized in that: the concentration of described electrolyte is 1.0~2.0 mol.
According to described high working voltage super capacitor, it is characterized in that: two annulus groups of cation are five-membered ring in the described electrolyte salt, X
-Be BF
4 -Electrolyte solvent is selected the mixed solvent of ethylene carbonate (EC) and propene carbonate (PC) for use, and wherein: ethylene carbonate (EC) is 1: 1 with the weight ratio of propene carbonate (PC), and the concentration of electrolyte is 1.0mol/L.
According to described high working voltage super capacitor, it is characterized in that: described electrolyte solvent is selected propene carbonate (PC) for use, and the concentration of electrolyte is 1.3mol/L.
According to described high working voltage super capacitor, it is characterized in that: described positive active material can be identical with negative electrode active material, also can be different, can select a kind of of porous active carbon, carbon black, carbon nano-fiber, carbon aerogels, carbon nano-tube, vitreous carbon or their mixing for use; Described anodal binding agent and negative pole binding agent are selected polytetrafluoroethylene (PTFE), homopolymerization or copolymerization vinylidene (PVDF), modified polyacrylic acid and ester class thereof, butadiene-styrene rubber, polyvinyl alcohol, sodium carboxymethylcellulose for use; Described anodal conductive agent and cathode conductive agent are selected for use: acetylene carbon black, conductive carbon fibre, electrically conductive graphite; Described porous isolating membrane is selected the polymer-modified of polyethylene film, polypropylene screen or them, perhaps nonwoven fabrics or cellulose for use; The weight part ratio of described positive active material, binding agent, conductive agent is 70~95: 0~20: 0~10; The weight part ratio of described negative electrode active material, binding agent, conductive agent is 70~95: 0~20: 0~10.
According to described high working voltage super capacitor, it is characterized in that: the weight part ratio of described positive active material, binding agent, conductive agent is 70~95: 3~20: 2~10; The weight part ratio of described negative electrode active material, binding agent, conductive agent is 70~95: 3~20: 2~10.
According to described high working voltage super capacitor, it is characterized in that: also comprise plus plate current-collecting body and negative current collector, plus plate current-collecting body and negative current collector are selected for use: aluminium foil, aluminium net, Copper Foil, copper mesh, nickel foam, nickel foil or nickel screen, plus plate current-collecting body and negative current collector can be selected same kind of collector, also can select different collectors, also can not have collector.
According to described high working voltage super capacitor, it is characterized in that: described positive electrical pole piece, negative electricity pole piece, porous isolating membrane making rolling core are packed in the capacitor casing.
According to described high working voltage super capacitor, it is characterized in that:
Described positive active material is a porous activated carbon, and binding agent is Kynoar (PVDF), and conductive agent is an acetylene carbon black; Its weight portion proportioning is:
Porous activated carbon 90;
Kynoar (PVDF) 5;
Acetylene carbon black 5;
When making anode sizing agent, earlier 5 parts by weight of polyvinylidene fluoride (PVDF) are dissolved in the n-methlpyrrolidone (NMP) of 50 weight portions, and then the porous activated carbon of 90 weight portions, the acetylene carbon black of 5 weight portions are mixed, stir, disperse to make even anode sizing agent with it;
Described negative electrode active material is a porous active carbon, and binding agent is polyacrylic acid and derived ester thereof, and conductive agent is an acetylene carbon black; Its weight portion proportioning is:
Porous active carbon 90;
Binding agent polyacrylic acid and derived ester 5 thereof;
Acetylene carbon black 5;
When making cathode size, polyacrylic acid and the derived ester thereof with 5 weight portions is dissolved in the water of 300 weight portions earlier, and then the porous active carbon of 90 weight portions, the acetylene carbon black of 5 weight portions are mixed, stir, disperse to make even cathode size with it.
A kind of method of making described high working voltage super capacitor is characterized in that may further comprise the steps:
A. positive electrode active materials, binding agent, conductive agent are mixed, stir according to described weight part ratio;
B. negative active core-shell material, binding agent, conductive agent are mixed, stir according to described weight part ratio;
C. on plus plate current-collecting body, evenly apply and make the positive electrical pole piece;
D. on negative current collector, evenly apply and make the negative electricity pole piece;
E. positive electrical pole piece that step c and steps d are made and negative electricity pole piece respectively with the tablet press machine compacting to conventional compacted density; The compacted density of positive electrical pole piece and negative electricity pole piece is 0.5~1.0 gram per centimeter
3
F. cut positive electrical pole piece and negative electricity pole piece that step e makes;
G. cut porous isolating membrane;
H. the porous isolating membrane made of the positive electrical pole piece that step f is made and negative electricity pole piece, step g fits together;
I. add described high working voltage electrolyte;
J. high working voltage super capacitor is made in encapsulation.
The invention has the beneficial effects as follows: the present invention adopts the electrolytic solution for super capacitor of high working voltage, electrochemical window with broad, utilize its high electrochemical decomposition voltage, the high working voltage super capacitor of making is in the characteristics of the cycle performance that the high power density of reservation is become reconciled, have more high working voltage (3.0V~3.5V, the best is 3.3V) and higher energy density.
Embodiment
Below by embodiment ultracapacitor of the present invention and manufacture method thereof and performance are further described.
Embodiment 1:
The present invention makes the cylinder ultracapacitor as follows:
(1) makes anode sizing agent.Carry out the raw material proportioning according to following weight portion:
Porous activated carbon 90;
Binding agent Kynoar (PVDF) 5;
Conductive agent acetylene carbon black 5;
Manufacture method: earlier 5 parts by weight of polyvinylidene fluoride (PVDF) are dissolved in the n-methlpyrrolidone (NMP) of 50 weight portions, and then the porous activated carbon of 90 weight portions, the acetylene carbon black of 5 weight portions are mixed, stir, disperse to make even anode sizing agent with it.
(2) make cathode size.Carry out the raw material proportioning according to following weight portion:
Negative electrode active material porous active carbon 90;
Binding agent polyacrylic acid and derived ester 5 thereof;
Conductive agent acetylene carbon black 5;
Manufacture method: polyacrylic acid and the derived ester thereof with 5 weight portions is dissolved in the water of 300 weight portions earlier, and then the porous active carbon of 90 weight portions, the acetylene carbon black of 5 weight portions are mixed, stir, disperse to make even cathode size with it.
(3) the anode sizing agent curtain coating is coated on aluminium foil surface and makes the positive electrical pole piece, on tablet press machine, suppress, cut into suitable dimensions.Anode sizing agent of the present invention can be coated on the one or both sides of aluminium foil.Positive electrical pole piece compacted density is 0.5~1.0 gram per centimeter
3
(4) the cathode size curtain coating is coated on aluminium foil surface and makes the negative electricity pole piece, on tablet press machine, suppress, cut into suitable dimensions.Cathode size of the present invention can be coated on the one or both sides of aluminium foil.Negative electricity pole piece compacted density is 0.5~1.0 gram per centimeter
3
(5) porous isolating membrane is cut into suitable dimensions.
(6) with the positive electrical pole piece of suitable dimension, the negative electricity pole piece of suitable dimension, the porous isolating membrane coiling core of suitable dimension.The present invention also can make electrode by other conventional methods.
(7) the volume core in the step 6 is packed in the metal aluminum hull.
(8) perfusion high working voltage electrolyte.Electrolyte salt is selected for use
Wherein, cation is a quaternary alkylphosphonium salt, is made up of two close ring groups, and two annulus groups are five-membered ring, X
-Be BF
4 -
Electrolyte solvent is selected the mixed solvent of ethylene carbonate (EC) and propene carbonate (PC) for use, and wherein: ethylene carbonate (EC) is 1: 1 with the weight ratio of propene carbonate (PC); The concentration of electrolyte is 1.0mol/L.
Perhaps, electrolyte solvent is selected propene carbonate (PC) for use, and the concentration of electrolyte is 1.3mol/L.
(9) encapsulation makes hybrid super capacitor product of the present invention.
Comparative Examples 1:
Positive electrical pole piece and negative electricity pole piece are all used negative electricity pole piece among the embodiment 1.
Wherein step (8) is the present widely used electrolytic solution for super capacitor of perfusion.Electrolyte salt is selected lithium hexafluoro phosphate (LiPF for use
6); Electrolyte solvent is selected the mixed solvent of ethylene carbonate (EC) and propene carbonate (PC) for use, and wherein: ethylene carbonate (EC) is 1: 1 with the weight ratio of propene carbonate (PC).The concentration of electrolyte is 1.0mol/L.
Make contrast product of the present invention---the cylinder ultracapacitor of Comparative Examples 1.
Make Φ 16 * 26 (cylinder ultracapacitor respectively according to the above embodiments 1 and Comparative Examples 1, diameter 16mm, the height 26mm) product compare: the product operating voltage 3.3V of embodiment 1, energy density 20Wh/kg, cycle-index 50,000 times (80% capability retention); The product operating voltage 2.5V of Comparative Examples 1, energy density 12Wh/kg, cycle-index 50,000 times (80% capability retention).
Embodiment 2:
With reference to embodiment 1, step is made button ultracapacitor of the present invention by the following method.
(1) anode sizing agent and cathode size carry out the raw material proportioning according to following weight portion:
Porous activated carbon 93;
Acetylene carbon black 5;
Polytetrafluoroethylene 2;
Manufacture method: the porous activated carbon of 93 weight portions, the acetylene carbon black of 5 weight portions are mixed, stir with it, obtain homodisperse mixed powder.
(2) adopt tablet machine to make 0.5~1.0 gram per centimeter according to the requirement of the electrode size of manufacturing ultracapacitor
3The muffin of density.
(3) cut barrier film according to the requirement of barrier film size;
(4) a slice ultracapacitor positive electrical pole piece, a slice super capacitor anode electrode slice, a slice porous isolating membrane lamination are obtained pie ultracapacitor core body together;
(5) above-mentioned pie ultracapacitor core body is packed in anodal cap of button and the button negative pole cap;
(6) add high working voltage super capacitor electrolyte;
(7) be packaged into the button ultracapacitor.
Comparative Examples 2:
Positive electrical pole piece and negative electricity pole piece are all used negative electricity pole piece among the embodiment 1.
Wherein step (8) is the present widely used electrolytic solution for super capacitor of perfusion.Electrolyte salt is selected lithium hexafluoro phosphate (LiPF for use
6); Electrolyte solvent is selected the mixed solvent of ethylene carbonate (EC) and propene carbonate (PC) for use, and wherein: ethylene carbonate (EC) is 1: 1 with the weight ratio of propene carbonate (PC).The concentration of electrolyte is 1.0mol/L.
Make contrast product of the present invention---Comparative Examples 2 button ultracapacitors, operating voltage 2.7V.
Button ultracapacitor of the present invention, button shell diameter 4.8mm, thickness 1.4mm, operating voltage 3.3V compares with the ultracapacitor of Comparative Examples 2, and operating voltage is increased to 3.3V by 2.7V.
The above only is preferred embodiment of the present invention, and the various variations that those skilled in the art carries out in not breaking away from claim limited range of the present invention are all within protection scope of the present invention.