A kind of rear surface of solar cell silver paste of high electricity conversion and preparation method thereof
Technical field
The present invention relates to solar cell photovoltaic field of material technology, specially solar energy crystal silicon cell back side silver paste
And preparation method thereof.
Background technology
Solar energy crystalline silicon photovoltaic electricity generation system is the photovoltaic effect using silion cell semiconductor, and solar radiation energy is straight
Switch through a kind of new power generating system for being changed to electric energy, due to its green feature, obtain fast development in the whole world at present.
At present, the cost of solar cell and transformation efficiency, which turn into, restricts its bottleneck further developed.Solar energy crystal silicon cell is carried on the back
The left and right of collected current is played with silver paste in face.
The back side with the important component that silver paste is solar cell, by silver powder, glass dust, organic bond and other help
Agent is prepared, and the silion cell back side is printed on by screen printing technique, is first of slurry of silk-screen, after sintering
Backplate is formed, collects the electric current of formation.Back silver paste requires excellent printing performance, electric conductivity, weldability
Energy and adhesive force.Silver powder plays a part of conductive and welding as function of tonic chord phase in back silver paste;Glass dust is as slave function
Phase, the important function of bonding silver powder is played in sintering process.
At present, as problems with occur in the continuous decline for carrying on the back silver-colored silver content, back of the body silver:
1. the reduction of silver content causes adhesive force to occur declining.
2. the reduction of silver content causes welding performance to occur declining.
3. the reduction of silver content causes electrical performance of cell to occur declining.
The content of the invention
The present invention is according to above-mentioned deficiency, there is provided a kind of adhesive force is good, welding performance is strong, the cell piece of high conversion efficiency
With back side silver paste.
Technical problem solved by the invention is realized using following technical scheme:
A kind of back silver paste of solar cell of high electricity conversion, the weight percentage of each component are:Irregularly
Flake silver powder 10~20%, dendroid silver powder 10~25%, lenticular ball shape silver powder 10-30%, nano-silver powder 5%-15%, glass
Glass powder 2.5%-7.5%, polymolecularity organic bond 30%-55%, adhesion promoter 0.1%-5%, auxiliary agent 0.5-
3%, the percetage by weight sum of each component is 100%.
Irregular flake silver powder, dendroid silver powder, lenticular ball shape silver powder, the percetage by weight sum of nano-silver powder
For 40-65%.
It with certain thickness flake silver powder, the silver powder thickness is the 2-3 of conventional sheet silver that the irregular flake silver powder, which is,
Times, average grain diameter is 1.5-2.5 microns, and purity is more than 99.90%.
The nano-silver powder is the nano-silver powder for having high dispersive characteristic, is disperseed using organic solvent, is disperseed used
Organic solvent does not conflict with whole slurry system, and the average grain diameter of nano-silver powder is 5-10 nanometers, and purity is more than 99.90%.
Described glass dust is made up of the raw material of following mass ratio:Bi2O320-60%, PbO 0-20%, ZnO 10-
30%, Al2O35-25%, SiO24-19%, CaO 0.5-11%, BaO 1.2-10%, other micro amount of oxygen compounds 0.5-3%.
Other described micro amount of oxygen compounds are Ga2O3, MnO2, Fe2O3One or more of compositions in several oxides.
Described polymolecularity organic bond is made up of the raw material of following mass ratio:Terpinol 5%-72%, butyl card
Must alcohol 12-38%, butyl carbitol acetate 5-15%, ethyl cellulose 3-8%, propandiol butyl ether 0.5-10%, ethylene glycol
0.3-1.5%, butyl acetate cellulose 2-3%.
Described adhesion promoter is to add without polysiloxane non-ionic compound and the conventional use of adhesive force of industry
Add agent.
Described auxiliary agent is that esters of acrylic acid levelling agent, organobentonite class thixotropic agent, lipophile dispersant and industry are normal
Advise the auxiliary agent used.
The preparation process of the rear surface of solar cell silver paste of the high electricity conversion is:
(1) preparation of glass dust:Weighed by formula rate prepare glass dust raw material it is well mixed after, in vacuum drying oven
100~200 DEG C of drying 2.5-3.5 hours;Then the melting 0.5-1.8 hours at 800-1600 DEG C, dried after deionization water quenching,
Ball milling 300-1000 minutes are carried out again, are sieved after drying and are obtained the glass dust that average grain diameter is less than 5 microns.
(2) preparation of polymolecularity organic bond:Carried out after the raw material for preparing organic bond is weighed by formula rate
It is scattered at a high speed, then dissolved by heating under 70-150 degrees Celsius, dissolution time is 80-240 minutes.
(3) by formula, by polymolecularity organic bond prepared by glass dust prepared by silver powder, step (1), step (2)
After being configured to slurry, first carry out scattered be ground again at a high speed and roll slurry 5~15 times, finally give back of the body silver of the fineness less than 15 microns
Slurry.
Need to be ground after the raw material mixing of glass dust in the step (1) it is scattered, reach color it is homogeneous after dried.
In step (2) polymolecularity organic bond prepare non-solid component need to first be stirred after again substep add resin and
Auxiliary agent.Need that first the slurry prepared is uniformly dispersed in step (3), be then ground in ball mill, finally roll
Meet to require.It is using three-high mill and ball mill that slurry is rolled in grinding of the present invention.
The advantages of the present invention are:
1. the present invention has excellent performance, conversion ratio exceedes existing slurry.
2 present invention have simple preparation method, and preparation cost is low, and production is stable.
3 adhesive force of the present invention are good, environmentally safe.
Auxiliary agent and additive that 4 present invention use have greatly facilitated the overall performance of slurry.
Embodiment:
The present invention is expanded on further below by the detailed description of embodiment, is not limitation of the present invention,
Protection scope of the present invention is not limited in following instance.The technical field personnel according to above present disclosure and
Method, the reachable purpose of the present invention.
Raw material of the present invention is commercially available convenient source, and equipment is industry conventional equipment.
Embodiment 1
(1) glass dust is prepared:Weigh:Bi2O342.7%, PbO 15.8%, ZnO 27.2%, Al2O3 5.4%, SiO2
7.2%, CaO 0.6%, BaO 2.6%, other micro amount of oxygen compounds 2.6%.Wherein micro amount of oxygen compound is following several oxides
In one or more:Ga2O3, MnO, Fe2O3Deng.After well mixed, dried 2.75 hours for 125 DEG C in vacuum drying oven;Then
Melting 0.9 hour at 1360 DEG C, is dried after deionization water quenching, then carries out ball milling 750 minutes, is sieved after drying and is obtained average grain
Footpath is less than 5 microns of glass dust.
(2) organic system is prepared:Weigh:Terpinol 55.4%, butyl carbitol 25.26%, butyl carbitol acetate
7.6%, ethyl cellulose 4.7%, 3.8% propandiol butyl ether, 0.47% ethylene glycol, 2.77% butyl acetate fiber
Element.
(3) silver powder:Lenticular ball shape silver powder purity is more than 99.97%, and average grain diameter is 0.74 micron;Flake silver powder purity
More than 99.90%, average grain diameter is 4.1 microns;Nano-silver powder purity is more than 99.98%, and average grain diameter is 6.4 nanometers;Branch
Shape silver powder purity is more than 99.92%, and average grain diameter is 1.77 microns.
(4) adhesive force additive:Without polysiloxane non-ionic compound and the conventional use of adhesive force additive of industry.
(5) auxiliary agent:Esters of acrylic acid levelling agent, organobentonite class thixotropic agent, lipophile dispersant and industry routinely make
Auxiliary agent.
According to silver powder 51.1%, glass dust 4.9%, organic solvent 40%, adhesive force additive 1.5%, auxiliary agent 2.5%,
Carry out disperseing at a high speed 0.5 hour after well mixed, then rolled 13 times using three-high mill, fineness of grind to 9 microns, viscosity is
35000mpa·S.Obtain high transformation efficiency cell piece back side silver paste.By slurry with 325 mesh screen paintings in silicon solar cell
125mm × 125mm back sides, photoelectric transformation efficiency survey is carried out after cell piece is made according to crystal silicon solar cell sheet Making programme
Examination, testing mean reach 18.7%.Cell piece after the completion of above-mentioned test is subjected to adhesive force test, existed with Pb-free coating band
Welded under 330 degree, then 180 degree carries out pullling test, and test result shows that adhesive force is all higher than 8N.
Embodiment 2
(1) glass dust is prepared:Weigh:Bi2O322.5%, PbO 19.1%, ZnO 30%, Al2O3 15.4%, SiO2
4.1%, CaO 0.7%, BaO 1.3%, other micro amount of oxygen compounds 2.8%.Wherein micro amount of oxygen compound is following several oxides
In one or more:Ga2O3, MnO, Fe2O3Deng.After well mixed, dried 2.75 hours for 125 DEG C in vacuum drying oven;Then
Melting 0.9 hour at 1360 DEG C, is dried after deionization water quenching, then carries out ball milling 750 minutes, is sieved after drying and is obtained average grain
Footpath is less than 5 microns of glass dust.
(2) organic system is prepared:Weigh:Terpinol 41.29%, butyl carbitol 36.37%, butyl carbitol acetate
10.5%, ethyl cellulose 5.7%, 2.9% propandiol butyl ether, 0.47% ethylene glycol, 2.77% butyl acetate fiber
Element.
(3) silver powder:Lenticular ball shape silver powder purity is more than 99.97%, and average grain diameter is 0.74 micron;Flake silver powder purity
More than 99.90%, average grain diameter is 4.1 microns;Nano-silver powder purity is more than 99.98%, and average grain diameter is 6.4 nanometers;Branch
Shape silver powder purity is more than 99.92%, and average grain diameter is 1.77 microns.
(4) adhesive force additive:Without polysiloxane non-ionic compound and the conventional use of adhesive force additive of industry.
(5) auxiliary agent:Esters of acrylic acid levelling agent, organobentonite class thixotropic agent, lipophile dispersant and industry routinely make
Auxiliary agent.
According to silver powder 55.5%, glass dust 4.5%, organic solvent 36%, adhesive force additive 1.5%, auxiliary agent 2.5%,
Carry out disperseing at a high speed 0.5 hour after well mixed, then rolled 13 times using three-high mill, fineness of grind to 9 microns, viscosity is
39000mpa·S.Obtain high transformation efficiency cell piece back side silver paste.By slurry with 325 mesh screen paintings in silicon solar cell
125mm × 125mm back sides, photoelectric transformation efficiency survey is carried out after cell piece is made according to crystal silicon solar cell sheet Making programme
Examination, testing mean reach 18.7%.Cell piece after the completion of above-mentioned test is subjected to adhesive force test, existed with Pb-free coating band
Welded under 330 degree, then 180 degree carries out pullling test, and test result shows that adhesive force is all higher than 8N.
Slurry |
Pmpp |
Uoc |
Isc |
Rs |
Rsh |
FF |
NCell |
Contrast |
4.28477 |
0.62979 |
8.583254 |
0.003117 |
190.8252 |
78.78507 |
0.181958 |
Embodiment 2 |
4.293052 |
0.630909 |
8.63821 |
0.002839 |
192.249 |
79.06055 |
0.189298 |
Embodiment 3
(1) glass dust is prepared:Weigh:Bi2O335.5%, PbO 15.5%, ZnO 25%, Al2O3 15%, SiO2
4%, CaO 0.7%, BaO 1.3%, other micro amount of oxygen compounds 3%.Wherein micro amount of oxygen compound is in following several oxides
It is one or more of:Ga2O3, MnO, Fe2O3Deng.After well mixed, dried 2.75 hours for 125 DEG C in vacuum drying oven;Then exist
Melting 0.9 hour at 1360 DEG C, is dried after deionization water quenching, then carries out ball milling 750 minutes, and being sieved after drying obtains average grain diameter
Glass dust less than 5 microns.
(2) organic system is prepared:Weigh:Terpinol 40%, butyl carbitol 35%, butyl carbitol acetate 15%,
Ethyl cellulose 5%, 2% propandiol butyl ether, 0.5% ethylene glycol, 2.5% butyl acetate cellulose.
(3) silver powder:Lenticular ball shape silver powder purity is more than 99.97%, and average grain diameter is 0.74 micron;Flake silver powder purity
More than 99.90%, average grain diameter is 4.1 microns;Nano-silver powder purity is more than 99.98%, and average grain diameter is 6.4 nanometers;Branch
Shape silver powder purity is more than 99.92%, and average grain diameter is 1.77 microns.
(4) adhesive force additive:Without polysiloxane non-ionic compound and the conventional use of adhesive force additive of industry.
(5) auxiliary agent:Esters of acrylic acid levelling agent, organobentonite class thixotropic agent, lipophile dispersant and industry routinely make
Auxiliary agent.
According to silver powder 48.9%, glass dust 4.1%, organic solvent 41%, adhesive force additive 4.5%, auxiliary agent 1.5%,
Carry out disperseing at a high speed 0.5 hour after well mixed, then rolled 13 times using three-high mill, fineness of grind to 9 microns, viscosity is
25000mpa·S.Obtain high transformation efficiency cell piece back side silver paste.By slurry with 325 mesh screen paintings in silicon solar cell
125mm × 125mm back sides, photoelectric transformation efficiency survey is carried out after cell piece is made according to crystal silicon solar cell sheet Making programme
Examination, testing mean reach 18.7%.Cell piece after the completion of above-mentioned test is subjected to adhesive force test, existed with Pb-free coating band
Welded under 330 degree, then 180 degree carries out pullling test, and test result shows that adhesive force is all higher than 8N.
Slurry |
Pmpp |
Uoc |
Isc |
Rs |
Rsh |
FF |
NCell |
Contrast |
4.28477 |
0.62979 |
8.583254 |
0.003117 |
190.8252 |
78.78507 |
0.181958 |
Embodiment 3 |
4.29935 |
0.631067 |
8.626596 |
0.002822 |
192.7703 |
79.13188 |
0.190268 |