JP6374774B2 - Manufacturing method of solar cell - Google Patents

Description

  The present invention relates to a method for manufacturing a solar cell.

As a conventional method for manufacturing a solar cell, as shown in the following patent document, while conveying a long first electrode and a long second electrode, both ends in the width direction are directed from one end side to the other end side. A so-called Roll-to-Roll manufacturing method is disclosed in which bonding is performed gradually.
When a solar cell is manufactured using this method, the working efficiency is improved by filling an electrolyte between the first electrode and the second electrode immediately before bonding the first electrode and the second electrode. Therefore, when using the Roll-to-Roll manufacturing method, either the first electrode or the second electrode is laid flat, and a large amount of electrolyte is filled on the surface of the electrode, and the other electrode is connected to one end. A method of adhering an excess electrolyte solution from one end to the other end toward the tip and adhering to one electrode while deaeration is conceivable.

JP 2012-099831 A

However, if the surface of one electrode is filled with a large amount of electrolyte, the electrolyte will overflow to both sides of one electrode when the other electrode is bonded and bonded. If it does so, since electrolyte solution adheres to the manufacturing apparatus of a solar cell, other bases, etc., there existed a problem that the operation | work which wipes off electrolyte solution was needed whenever electrolyte solution adhered.
Therefore, the present invention provides a method for manufacturing a solar cell in which the electrolyte does not easily overflow around the solar cell.

The manufacturing method of the solar cell of this invention provides a pair of 1st sealing part along each side which mutually opposes the 1st electrode formed in plate shape, Between a pair of said 1st sealing parts A first step of forming a liquid holding portion on the outside of the first step, a second step of filling the electrolytic solution between the first sealing portions, and a second electrode formed in a plate shape, The liquid electrode is gradually overlapped with the first electrode from one end side to the other end side in the direction along the side while overflowing the liquid holding portion, and the second electrode and the first electrode in the first sealing portion. And a third step of bonding the electrodes.
In the present invention, the electrolytic solution refers to a liquid or semi-solid electrolytic solution (hereinafter the same).
According to this configuration, when the electrolytic solution overflows outside between the first sealing portions, the electrolytic solution can be held in the liquid holding portion.

The liquid holding part of the present invention is formed between the first sealing part and a side wall that is provided outside the first sealing part and spaced apart from the first sealing part. It may be a groove.
According to this configuration, the overflowing electrolyte solution can be held in the groove.

You may arrange | position the absorber which absorbs the said electrolyte solution in the said groove | channel of this invention.
According to this configuration, since the electrolytic solution can be absorbed by the absorbent material, the flow of the electrolytic solution can be prevented.

A support member may be disposed in the groove of the present invention.
According to this configuration, when the second electrode is overlapped with the first electrode, the liquid holding unit is crushed, and the volume of the electrolytic solution that can be held in the liquid holding unit is reduced or accommodated in the liquid holding unit. It is possible to prevent the electrolyte from overflowing to the outside.

The liquid holding part of the present invention may be formed by an absorptive side wall provided adjacent to the first sealing part.
According to this configuration, the configuration of the liquid holding unit can be made compact.

  The present invention has an effect of making it possible to efficiently manufacture a solar cell by preventing the electrolyte from overflowing around the solar cell.

It is sectional drawing which showed typically 1 process of the manufacturing method of the solar cell of one Embodiment of this invention. It is sectional drawing which showed typically 1 process of the manufacturing method of the solar cell of one Embodiment of this invention. It is the top view which showed typically 1 process of the manufacturing method of the solar cell of one Embodiment of this invention. It is sectional drawing which showed typically 1 process of the manufacturing method of the solar cell of one Embodiment of this invention. It is the top view which showed typically 1 process of the manufacturing method of the solar cell of one Embodiment of this invention. It is sectional drawing which showed typically 1 process of the manufacturing method of the solar cell of one Embodiment of this invention. It is sectional drawing which showed typically 1 process of the manufacturing method of the solar cell of one Embodiment of this invention. It is sectional drawing which showed typically 1 process of the modification of the manufacturing method of the solar cell of one Embodiment of this invention. It is sectional drawing which showed typically 1 process of the modification of the manufacturing method of the solar cell of one Embodiment of this invention.

Hereinafter, an embodiment of a method for manufacturing a solar cell of the present invention will be described with reference to the drawings.
The manufacturing method of the solar cell of this embodiment is as follows:
(1) As shown in FIG. 1, a pair of first sealing portions 2, 2 is provided along each side 1 a of the first electrode 1 formed in a plate shape so as to face each other. A first step of forming the liquid holding portion 4 outside the sealing portions 2 and 2;
(2) As shown in FIG. 2, a second step of filling the electrolyte 3 between the first sealing portions 2 and 2;
(3) As shown in FIGS. 3 and 4, the second electrode 6 formed in a plate shape is moved from one end 6 m side in the direction along the side 1 a while overflowing the electrolyte 3 to the liquid holding portion 4. And a third step of gradually overlapping the first electrode 1 toward the end 6n side and bonding the second electrode 6 and the electrode 1 at the first sealing portions 2 and 2.

(1) First Step As shown in FIG. 1, in the first step, a pair of first sealing portions 2 along side sides 1 a facing each other of the first electrode 1 formed in a plate shape. , 2, and the liquid holding part 4 is formed outside the pair of first sealing parts 2, 2.

The first electrode 1 is formed by forming a conductive film 11a on the surface of the substrate 10a and further forming a semiconductor porous film 12 on the surface of the conductive film 11a.
The first electrode 1 is formed in a substantially rectangular or long band shape.
As a material of the substrate 10a used for the first electrode 1, for example, a resin material or a glass substrate or the like mainly composed of a transparent thermoplastic resin material such as polyethylene naphthalate (PEN) or polyethylene terephthalate (PET) is preferably used. Can be used. The substrate 10a is preferably formed in a flexible film shape.

  Examples of the material of the conductive film 11a include tin-doped indium oxide (ITO), zinc oxide, fluorine-doped tin oxide (FTO), aluminum-doped zinc oxide (AZO), tin oxide (SnO), antimony-doped tin oxide (ATO), Indium oxide / zinc oxide (IZO), gallium-doped zinc oxide (GZO), or the like can be used.

The semiconductor porous film 12 has a function of receiving and transporting electrons from a sensitizing dye described later, and a semiconductor made of a metal oxide, an organic metal, or the like is formed on the surface of the conductive film 11a. As the metal oxide, for example, titanium oxide (TiO ₂ ), zinc oxide (ZnO), tin oxide (SnO ₂ ), or the like can be used. As the organic metal, an organic metal having a perovskite structure such as CH ₃ NH ₃ PbX ₃ (X is a halogen atom) can be used.

  The semiconductor porous film 12 can carry a sensitizing dye. The sensitizing dye supported on the semiconductor porous film 12 is composed of an organic dye or a metal complex dye. As the organic dye, for example, various organic dyes such as coumarin, polyene, cyanine, hemicyanine, and thiophene can be used. As the metal complex dye, for example, a ruthenium complex is preferably used.

A pair of the sealing materials 2A are continuously arranged in the depth direction of the paper along the side 1a inside both ends in the width direction of the substrate 10a (that is, the direction crossing the side 1a extending in the depth direction of the paper). deep.
As the sealing material 2A, an adhesive (for example, a hot melt resin) or a curable resin can be suitably used.

  The surface of the conductive film 11a of the first electrode 1 is filled with a liquid or semi-solid electrolytic solution 3 (see FIG. 2) by arranging a sealing material 2A having a thickness (height). A recess 13 is formed. That is, the pair of sealing materials 2A and 2A facing each other can prevent the electrolyte 3 (see FIG. 2) from easily flowing down on both sides in the width direction of the first electrode 1. Further, the sealing material 2A disposed in the vicinity of both ends of the first electrode 1 in the width direction seals the first electrode 1 and the second electrode 6 in the vicinity of both ends in the width direction in the side 1a direction. The sealing part 2 is comprised.

Side walls 5 are provided on the outer side between the pair of first sealing portions 2, 2, that is, on both ends in the width direction of the substrate 10 a, with a space from the first sealing portion 2.
A groove 8 is formed between the first sealing part 2 and the side wall 5, and the liquid holding part 4 that holds the excess electrolyte solution 3 filled with the groove 8 is constituted.

Although it does not specifically limit for the side wall 5, Although the sealing material similar to the 1st sealing part 2 can be used, since the electrolyte solution 3 can be sealed and adhere | attached in the groove | channel 8. In particular, an adhesive is preferred.
Although not essential, the liquid holding unit 4 is provided with an absorbent material 9 that absorbs and holds the liquid.

The absorbent material 9 is not particularly limited as long as it is a material capable of holding a liquid, and examples thereof include a nonwoven fabric, a foam (sponge) capable of absorbing liquid, and a gel-like polymer material having water absorption. Among these, since the amount of liquid absorption can be increased, it is preferable to use a material having a high porosity. Moreover, it is preferable that the absorbent material 9 is disposed up to the height of the substantially upper surface of the groove 8.
In the present configuration in which the absorbent material 9 is disposed in the groove 8, the groove 8 and the absorbent material 9 constitute the liquid holding unit 4.

(2) Second Step In the second step, the electrolyte 3 is filled between the first sealing portions 2 and 2 as shown in FIG.
The electrolytic solution 3 is filled between the sealing materials 2 </ b> A of the first electrode 1, that is, between the first sealing portions 2 and 2. The amount of the electrolyte 3 to be filled is such that the electrolyte 3 is finally filled between the first electrode 1 and the second electrode 6 so as not to overflow between the first sealing portions 2 and 2. More than. Therefore, the electrolytic solution 3 is filled to such an extent that it slightly comes out from the upper end of the sealing material 2A.

  Examples of the electrolytic solution 3 include non-aqueous solvents such as acetonitrile and propionitrile; liquid components such as ionic liquids such as dimethylpropylimidazolium iodide and butylmethylimidazolium iodide; and a supporting electrolytic solution such as lithium iodide. A solution in which iodine and iodine are mixed can be used. Moreover, in order to prevent reverse electron transfer reaction, the electrolyte solution 3 may contain t-butylpyridine.

(3) Third Step In the third step, as shown in FIGS. 3 and 4, the second electrode 6 formed in a plate shape is placed on the side while causing the electrolyte 3 to overflow into the liquid holding unit 4. The first electrode 1 is gradually overlapped from the one end 6m side to the other end 6n side in the direction along the side 1a, and the second electrode 6 and the first electrode 1 are bonded to each other at the first sealing portion 2.

For the second electrode 6, a conductive film 11b is formed on the substrate 10b.
The material and shape of the substrate 10b are substantially the same as those of the substrate 10a of the first electrode 1 except that a flexible material is used.
The conductive film 11b of the second electrode 6 does not have a role of a catalyst layer (not shown) but has a role as the conductive film 11b, or a material that can function as both a catalyst layer (not shown) and the conductive film 11b. Either of these is used. In the former case, a catalyst layer (not shown) is further formed on the conductive film 11b. In the latter case, only the conductive film 11b is formed on another substrate 10b.
Moreover, a carbon paste, platinum, etc. can be employ | adopted as a catalyst layer formed into a film on the surface of the electrically conductive film 11b.

A transparent substrate is used as at least one of the substrate 10a of the first electrode 1 and the substrate 10b of the second electrode 6.
Moreover, at least one of the conductive films 11a and 11b of the first electrode 1 or the second electrode 6 is formed of a transparent conductive film.

The bonding of the second electrode 6 to the first electrode 1 is performed as follows.
That is, as shown in FIG. 3, the other end 6 n side of the second electrode 6 is lifted, and the one end 6 m side is bonded to the first electrode 1. The vicinity of the portion of the second electrode 6 bonded to the first electrode 1 is curved. And the part where the 2nd electrode 6 became curved shape is bonded together to the 1st electrode 1 gradually toward the other end 6n side from the one end 6m side.

  At this time, heating and light irradiation are performed according to the material of the sealing material 2A while pressurizing the first sealing portion 2, and the first electrode 1 and the second electrode 6 are bonded by the sealing material 2A. . When the second electrode 6 swells between the first sealing portions 2 and 2 due to the volume of the electrolytic solution 3, the first sealing portions 2 and 2A are slightly after pressurizing the sealing materials 2A and 2A. Level between the two with a roller.

  Since the electrolyte solution 3 disposed between the first sealing portions 2 and 2 is filled slightly more than the amount that is finally sealed, as shown in FIG. By bonding to one electrode 1, it is pressed from one end 6 m side to the other end 6 n side. As a result, the bubbles contained in the space S filled with the electrolytic solution 3 are pushed out from the bonding direction of the second electrode 6 to the first electrode 1 shown in FIG. 3, that is, from one end 6m side to the other end 6n side. . Moreover, the excess part of the electrolyte solution 3 is extruded toward the other end 6n side from the one end 6m side.

When the excess electrolyte solution 3 pushed out from the one end 6m side toward the other end 6n side gradually increases and overflows to the outside between the first sealing portions 2 and 2, the electrolyte solution 3 is shown in FIG. In this way, it flows into the outer groove 8 between the first sealing portions 2 and 2. Then, the electrolytic solution 3 is absorbed by the absorbent 9 disposed in the groove 8 and is held by the side wall 5 without flowing in the groove 8.
Accordingly, the liquid holding unit 4 holds the excess amount of the electrolyte solution 3 that is filled between the first sealing portions 2 and 2 of the first electrode 1, so that the excess electrolyte solution 3 is retained in the first electrode. It is prevented that it overflows outside 1 and adheres to a solar cell manufacturing apparatus or a base for manufacturing a solar cell.

(4) Subsequent step of the third step (step of sealing the space S filled with the electrolytic solution 3)
After the third step, as shown in FIGS. 5 and 6, the space S (see FIG. 6) filled with the electrolytic solution 3 is sealed. Specifically, the pair of second sealing portions 7 and 7 that extend in a direction crossing the side edge 1a between the side walls 5 and 5 and are set with an interval in the direction along the side edge 1a. The first electrode 1 and the second electrode 6 are bonded together.

The second sealing portion 7 is provided across the side walls 5 and 5 in the width direction. In the second sealing portion 7, the first electrode 1 and the second electrode 6 can be fused using ultrasonic fusion. And a solar cell is completed by cut | disconnecting leaving at least one part of the 2nd sealing part 7. FIG.
The solar cell may be provided with the liquid holding part 4 that holds the excess electrolytic solution 3, but as shown in FIG. 7, the electrolytic solution 3 is left in a part of the first sealing part 2. It can cut | disconnect and discard it, sealing to the liquid holding | maintenance part 4 with the 1 sealing part 2 and the 2nd sealing part.

  As described above, the method for manufacturing the solar cell according to the present embodiment is unidirectional while pressing the electrolytic solution 3 against the first electrode 1 in which the electrolytic solution 3 is filled between the first sealing portions 2 and 2. In order to bond the second electrode 6 together, the first electrode 1 and the second electrode 6 are bonded together while removing bubbles present in the space filled with the electrolytic solution 3. Therefore, the solar cell manufacturing method of the present embodiment has an effect that the deterioration of the quality of the solar cell due to the presence of bubbles in the solar cell filled with the electrolytic solution 3 can be obtained.

  At this time, in the method for manufacturing the solar cell according to the present embodiment, even if the electrolyte 3 overflows to the outside between the first sealing portions 2 and 2, the liquid holding formed on the outside of the first sealing portion 2 is maintained. Since the electrolytic solution 3 can be held by the portion 4, the electrolytic solution 3 can be prevented from soiling the periphery of the solar cell. Therefore, the method for manufacturing a solar cell according to the present embodiment has an effect that the production of the solar cell can be efficiently performed by preventing the occurrence of an operation of wiping off the excess electrolyte 3 attached to the periphery of the solar cell. Play.

  Moreover, since the manufacturing method of the solar cell of this embodiment arrange | positions the absorber 9 in the groove | channel 8, it prevents that the liquid holding | maintenance part 4 is crushed when the 2nd electrode 6 is piled up on the 1st electrode 1. FIG. Can do. Therefore, the solar cell manufacturing method of the present embodiment reduces the volume of the electrolytic solution 3 that can be held in the liquid holding unit 4 or causes the electrolytic solution contained in the liquid holding unit to overflow to the outside. This has the effect that the solar cell can be efficiently manufactured.

  Moreover, the manufacturing method of the solar cell of this embodiment can discard the overflowing electrolyte solution 3 easily by cutting off the liquid holding | maintenance part 4 in the 1st sealing part 2. FIG. Therefore, the manufacturing method of the solar cell of this embodiment has an effect that the solar cell can be manufactured efficiently.

  Further, according to the method for manufacturing a solar cell of the present embodiment, the constituent members of the solar cell can be arranged in the stacking order, so that an effect of facilitating manufacture and facilitating continuous production is obtained.

  As mentioned above, although one embodiment of the present invention has been described, the present invention is not limited to the configuration shown in the above embodiment, and each configuration can be appropriately changed and applied without departing from the essence of the invention. it can.

Specifically, the present invention can be applied to a case where a plurality of power generation elements (solar cells) are formed on one substrate, for example, as shown in FIG.
Even when it is desired to form a plurality of power generating elements on one substrate, as shown in FIG. 8, outside the first sealing portions 2 and 2 provided in the vicinity of both ends in the width direction of the one substrate (more A pair of side walls 5 are formed on both ends) at a distance from the first sealing portion 2, and a groove 8 serving as the liquid holding portion 4 is formed between the first sealing portion 2 and the side walls 5. be able to. Although not essential, an absorbent material 9 is disposed in the groove 8.

Then, as described in the above embodiment, the first electrode 1 and the second electrode 6 are made of the first sealing material while the second electrode 6 is arranged and the excess electrolyte 3 overflows into the groove 8. It can be sealed.
In addition, the conductive film straddling between the power generation elements, for example, appropriately forms the insulating portion 15 and the like, and arranges the conductive material 16 between the power generation elements to connect the power generation elements in series or in parallel (directly in FIG. 9). be able to.

In the above embodiment, the absorbent material 9 is also used as a support member. However, if the absorbent material 9 is difficult to function as a support member, a separate support member may be provided in the groove 8.
Moreover, in the said embodiment, although the liquid holding part 4 was set as the structure provided with the groove | channel 8 and the absorber 9 by providing the side wall 5, the side wall 5 which has absorptivity was made to adjoin the 1st sealing part 2. FIG. It may be a configuration. Specifically, the absorptive side wall 5 only needs to be capable of sufficiently absorbing and holding, for example, the overflowing electrolyte solution 3 and preventing the outward flow of the first electrode 1. The liquid holding unit 4 may be provided only by a configuration in which the side wall 5 having the gap is adjacent to the first sealing unit 2.

  In the first embodiment and the second embodiment, the first electrode 1 is used as a photoelectrode and the second electrode 6 is used as a counter electrode. Although the example in which 3 is filled has been described, the first sealing portions 2 and 2 may be provided on the second electrode 6 to fill the electrolyte solution 3.

  Moreover, although it is preferable to stick the 2nd sealing parts 7 and 7 in 1st Embodiment, 2nd Embodiment, or these modifications by ultrasonic fusion, it uses an adhesive agent etc. It is also possible to do this.

DESCRIPTION OF SYMBOLS 1 ... 1st electrode, 1a ... Side, 2A ... 1st sealing part, 3 ... Electrolyte solution, 4 ... Liquid holding part, 5 ... Side wall, 6 ... 2nd electrode, 7 ... 2nd sealing part, 8 ... groove (liquid holding part), 9 ... absorbent, 10a, 10b ... substrate

Claims (5)

A pair of first sealing portions is provided along the opposing sides of the first electrode formed in a plate shape, and a liquid holding portion is formed outside the pair of first sealing portions. 1 process,
A second step of filling an electrolyte between the first sealing portions;
The second electrode formed in a plate shape is gradually overlapped with the first electrode from one end side to the other end side in the direction along the side while causing the electrolyte solution to overflow the liquid holding portion, A third step of bonding the second electrode and the first electrode in the first sealing portion;
The manufacturing method of the solar cell which has this.   The liquid holding part is a groove formed between the first sealing part and a side wall that is spaced apart from the first sealing part and provided outside the first sealing part. The method for producing a solar cell according to claim 1.   The method for manufacturing a solar cell according to claim 2, wherein an absorbent that absorbs the electrolytic solution is disposed in the groove.   The method for manufacturing a solar cell according to claim 2, wherein a support member is disposed in the groove.   2. The method for manufacturing a solar cell according to claim 1, wherein the liquid holding portion is provided adjacent to the first sealing portion and is formed by an absorptive side wall.

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