WO2024157590A1 - Solar battery cell - Google Patents

Abstract

The present invention provides a solar cell that suppresses ingress of atmospheric moisture etc. as compared to the prior art.　The solar cell comprises a first electrode part (21) and a resin covering part (23) that is adjacent to the first electrode part (21), wherein the first electrode part (21) and the resin covering part (23) constitute part of a first main surface (10), the first main surface (10) has an inner edge region (130) constituted by the first electrode part (21) and the resin covering part (23), and an edge of the inner edge region (130) is formed within the range of 0.5 mm or less from an outer peripheral edge.

Description

Solar Cell

The present invention relates to a solar cell.

2. Description of the Related Art In recent years, solar cell modules have become known in which a panel-shaped solar cell is divided into a plurality of rectangular divided solar cells, and the ends of the divided solar cells are electrically connected to each other (for example, Patent Document 1).
The solar cell module of Patent Document 1 has divided solar cells connected by overlapping their ends (called a shingling connection), which makes it possible to increase the effective light-receiving area and is thought to have a higher conversion efficiency than conventional modules.

International Publication No. 2020/158379

Incidentally, dividing a solar cell into a plurality of divided solar cells is often carried out in the atmosphere.
However, the solar cell of Patent Document 1 uses a transparent conductive oxide, which is generally a porous material, as the transparent conductive layer. Therefore, if the division work is performed in the air, moisture and the like in the air may penetrate through the transparent conductive layer to the photoelectric conversion section, which may degrade the performance of the solar cell module.

The present invention aims to provide a solar cell that can suppress the intrusion of moisture and other substances from the atmosphere, compared to conventional solar cells.

One aspect of the present invention for solving the above-mentioned problems is a solar cell having a first electrode portion and a resin coating portion adjacent to the first electrode portion, the first electrode portion and the resin coating portion constituting a part of a first main surface, the first main surface having an inner edge region constituted by the first electrode portion and the resin coating portion, and the edge of the inner edge region is formed within a range of 0.5 mm from the outer periphery.

In this aspect, the inner edge region formed within a range of 0.5 mm from the outer periphery is composed of the first electrode portion and the resin coating portion, so that it is possible to prevent moisture and the like from entering in the thickness direction from the first main surface.

In a preferred embodiment, the first electrode portion and the resin coating portion include a continuously connected resin portion.

In a preferred aspect, the total area of the resin-coated portion of the inner edge region is greater than the total area of the first electrode portion.

In a preferred aspect, the first electrode portion has at least two finger electrode portions, the two finger electrode portions extend in substantially the same direction and are arranged side by side at a distance in a direction intersecting the extending direction, and the inner edge region is constituted by the resin coating portion between the two finger electrode portions.

Here, "extending in substantially the same direction" means being substantially parallel.
Here, "substantially parallel" does not only refer to the case where the centerlines are completely parallel, but also includes the case where the absolute value of the inclination angle of one centerline relative to the other centerline is 3 degrees or less.

In a preferred aspect, the first electrode portion and the resin coating portion are formed on the first substrate main surface of the photoelectric conversion substrate, the photoelectric conversion substrate has a textured structure formed on the first substrate main surface, and the resin coating portion has an uneven region in which unevenness smaller than the unevenness of the textured structure is formed.

In a preferred aspect, the resin coating portion covers the unevenness of the textured structure, thereby forming the uneven area.

In a preferred aspect, the first electrode portion and the resin coating portion are formed on the first substrate main surface of the photoelectric conversion substrate, the photoelectric conversion substrate has a pn junction in which a p-type semiconductor and an n-type semiconductor are joined directly or via an intrinsic semiconductor in the thickness direction, and the pn junction is formed on the first main surface side of the center of the photoelectric conversion substrate in the thickness direction.

In this aspect, the pn junction, which is the reaction site, is located close to the first electrode and the resin coating, so it is less susceptible to the effects of moisture, etc. when generating electricity at the pn junction.

In a preferred aspect, a transparent conductive layer is disposed in a position overlapping the inner edge region when viewed in a plan view, and the first electrode portion and the resin coating portion cover the transparent conductive layer.

In a more preferred aspect, the first electrode portion is laminated on a transparent conductive layer, the first main surface has a transparent conductive layer-free region where no transparent conductive layer is formed, and the resin coating portion coats the transparent conductive layer along the outer periphery of the transparent conductive layer and extends from the transparent conductive layer to the transparent conductive layer-free region.

One aspect of the present invention is a solar cell having a photoelectric conversion substrate having a photoelectric conversion section and a transparent conductive layer, a first electrode section formed on the transparent conductive layer, and a resin coating section adjacent to the first electrode section, the photoelectric conversion section having an exposed portion from the transparent conductive layer at its outer periphery when viewed in a plan view, and the resin coating section coating the transparent conductive layer along the outer periphery of the transparent conductive layer and being provided across from the transparent conductive layer to the exposed portion of the photoelectric conversion section.

In this aspect, the resin coating portion coats the transparent conductive layer along the outer periphery of the transparent conductive layer and covers the end faces of the transparent conductive layer, so that it is possible to prevent moisture and the like from entering the direction of the interface between the photoelectric conversion portion and the transparent conductive layer.

The solar cell of the present invention can suppress the intrusion of moisture and other substances from the atmosphere compared to conventional methods.

1 is a perspective view of a stacked structure of solar cells according to a first embodiment of the present invention; FIG. 2 is a plan view of the solar cell of FIG. 1 . 2A is an explanatory diagram of the solar cell of FIG. 1, where FIG. 2A is an oblique view seen from the first cell main surface side, and FIG. 2B is an oblique view of the solar cell of FIG. 2A rotated in the direction of arrow R and seen from the second cell main surface side. 3A and 3B are explanatory views of the solar cell of FIG. 2, in which FIG. 3A is an end view of the AA cross section of FIG. 2, and FIG. 3B is an end view of the BB cross section of FIG. 5A and 5B are explanatory diagrams of the solar cell of FIG. 4, in which (a) is an enlarged view of region C in FIG. 4A, and (b) is an enlarged view of region D in FIG. 4A. 2 is a plan view of a solar cell module using divided solar cells obtained by dividing the solar cell of FIG. 1, with a first sealing member and a first sealing material omitted for ease of understanding. FIG. 7 is a cross-sectional end view of the solar cell module of FIG. 6, with hatching of the first and second encapsulants omitted for ease of understanding. FIG. 7 is a cross-sectional perspective view of the divided solar cell of FIG. 6. 2 is an explanatory diagram of the solar cell manufacturing process for manufacturing the solar cell of FIG. 1, where (a) is a cross-sectional view after the photoelectric conversion part forming process, and (b) is a cross-sectional view after the transparent conductive layer forming process. Note that (b) shows dots for the parts formed in each process, and hatching is omitted for the rest. 2 is an explanatory diagram of the solar cell manufacturing process for manufacturing the solar cell of FIG. 1, where (a) is a cross-sectional view after the first electrode forming process, and (b) is a cross-sectional view after the second electrode forming process. Note that (a) and (b) show dots for the parts formed in each process, and hatching is omitted for the rest. 2A and 2B are explanatory diagrams of the positional relationship between solar cells in a layered structure formation process for forming the layered structure of solar cells in FIG. 1, in which (a) is an end view of a vertical cross section, and (b) is an end view of a cross section in a direction perpendicular to the cross section of (a) (horizontal direction). 3 is an explanatory diagram of the solar cell processing step for processing the solar cell of FIG. 2, where (a) is a cross-sectional view after the laser step, and (b) is a cross-sectional view after the bending step. Note that (a) and (b) are omitted from hatching for ease of understanding. 1A and 1B are explanatory diagrams of the main parts of a solar cell of another embodiment of the present invention, in which (a) is a plan view of an embodiment in which a plurality of second finger electrode portions are located between first finger electrode portions, and (b) is a plan view of an embodiment in which a plurality of first finger electrode portions are located between second finger electrode portions. 1A and 1B are explanatory diagrams of a solar cell processing step for processing a solar cell according to another embodiment of the present invention, in which (a) is a cross-sectional view of the solar cell after a laser process, and (b) is a cross-sectional view of the solar cell after a folding process. Note that (a) and (b) are omitted from hatching for ease of understanding.

The following describes in detail an embodiment of the present invention.

The solar cell stack structure 1 of the first embodiment of the present invention (hereinafter simply referred to as the stack structure 1) has a plurality of solar cells 2, and is a stack in which the solar cells 2 are stacked in the top-to-bottom direction (the vertical direction Z) as shown in Figure 1.
That is, in the stacked structure 1, the solar cells 2 are stacked in a lying state, and the solar cells 2 on the upper level are stacked so that most of the solar cells 2 on the upper level overlap with the solar cells 2 on the lower level.
In the overlapping structure 1 of this embodiment, when viewed in a plan view, the solar cells 2 on the upper side are overlapped such that 90% or more of the solar cells 2 on the upper side overlap with the solar cells 2 on the lower side.
The number of stacked solar cells 2 constituting the stacked structure 1 is not particularly limited.

(Solar cell 2)
The solar cell 2 is used by being cut along parting lines L1 shown in Fig. 2 and divided into a plurality of rectangular divided solar cells 101, and as shown in Fig. 6 and Fig. 7, each divided solar cell 101 is connected directly or via a conductive adhesive 102 to form a solar cell module 100 having a solar cell group 103. In other words, the solar cell 2 is a solar cell in process that is a solar cell module 100 in process.

The solar cell 2 of this embodiment is a crystalline solar cell, and is a heterojunction solar cell.
As shown in Figure 3, the solar cell 2 is a plate-shaped cell having a first cell principal surface 10 (first principal surface) and a second cell principal surface 11 (second principal surface) as its two principal surfaces, and is provided with a photoelectric conversion substrate 20, a first electrode portion 21, a second electrode portion 22, a first resin coating portion 23, and a second resin coating portion 24.
As shown in FIG. 2 , the solar cell 2 has a quadrangular shape when the photoelectric conversion substrate 20 is viewed in plan, and has horizontal sides 30 and 31 extending in the horizontal direction X and vertical sides 32 and 33 extending in the vertical direction Y.
The solar cell 2 has horizontal sides 30 and 31 parallel to each other, and vertical sides 32 and 33 parallel to each other.

(Photoelectric conversion substrate 20)
4, the photoelectric conversion substrate 20 is a plate-like substrate having a first substrate main surface 28 and a second substrate main surface 29 as its two main surfaces, and includes a first transparent conductive layer 25, a photoelectric conversion section 26, and a second transparent conductive layer 27. Here, in the photoelectric conversion substrate 20 of this embodiment, the first substrate main surface 28 is the main light-receiving surface.

The transparent conductive layers 25 and 27 are conductive layers that form a pair and extract electricity from the photoelectric conversion section 26 , and are base conductive layers that form the base of the electrode sections 21 and 22 .
The transparent conductive layers 25 and 27 are not particularly limited as long as they are transparent and conductive, and are made of a transparent conductive oxide such as indium tin oxide (ITO), for example.

The photoelectric conversion portion 26 is a portion that converts light energy into electrical energy, and as shown in FIG. 5, includes a semiconductor substrate 35, a first intrinsic semiconductor layer 36, a first conductivity type semiconductor layer 37, a second intrinsic semiconductor layer 38, and a second conductivity type semiconductor layer 39.
The photoelectric conversion unit 26 has a first intrinsic semiconductor layer 36 and a first conductivity type semiconductor layer 37 stacked in this order on one main surface side (the first cell main surface 10 side) of the semiconductor substrate 35, and a second intrinsic semiconductor layer 38 and a second conductivity type semiconductor layer 39 stacked in this order on the other main surface side (the second cell main surface 11 side) of the semiconductor substrate 35.

The semiconductor substrate 35 is a base material having n-type or p-type conductivity, such as n-type silicon or p-type silicon.
The semiconductor substrate 35 has a conductivity type opposite to that of the first conductivity type semiconductor layer 37 and has the same conductivity type as that of the second conductivity type semiconductor layer 39 .
For example, when the semiconductor substrate 35 is made of a p-type semiconductor, the first conductive type semiconductor layer 37 is made of an n-type semiconductor, and the second conductive type semiconductor layer 39 is made of a p-type semiconductor. On the other hand, when the semiconductor substrate 35 is made of an n-type semiconductor, the first conductive type semiconductor layer 37 is made of a p-type semiconductor, and the second conductive type semiconductor layer 39 is made of an n-type semiconductor.
That is, in the photoelectric conversion section 26 , a pn junction is formed on the first cell main surface 10 side with respect to the semiconductor substrate 35 .
The pn junction is a portion where a p-type semiconductor and an n-type semiconductor are joined directly or via an intrinsic semiconductor in the thickness direction of the photoelectric conversion section 26, and is formed on the first cell main surface 10 side rather than the center of the thickness direction of the photoelectric conversion section 26.

The first intrinsic semiconductor layer 36 is a layer made of an intrinsic semiconductor such as i-type silicon.

The first conductive type semiconductor layer 37 is a semiconductor layer having n-type or p-type conductivity, such as n-type silicon or p-type silicon.

The second intrinsic semiconductor layer 38 is a layer made of an intrinsic semiconductor such as i-type silicon.

The second conductive type semiconductor layer 39 is a semiconductor layer having a p-type or n-type conductivity, such as p-type silicon or n-type silicon, and has a conductivity type different from that of the first conductive type semiconductor layer 37.

As shown in FIG. 5, the photoelectric conversion substrate 20 has first texture structures 80, 81 with surface irregularities formed on both one main surface (the surface facing the first substrate main surface 28) and the other main surface (the surface facing the second substrate main surface 29) of the semiconductor substrate 35.

In the photoelectric conversion substrate 20, the semiconductor layers 36, 37 on one main surface of the semiconductor substrate 35 reflect the unevenness of the first texture structure 80 of the semiconductor substrate 35, and a second texture structure 82 in which surface unevenness is formed is formed in the first conductivity type semiconductor layer 37.
In the photoelectric conversion substrate 20, the semiconductor layers 38, 39 on the other main surface of the semiconductor substrate 35 reflect the unevenness of the first texture structure 81 of the semiconductor substrate 35, and a second texture structure 83 in which surface unevenness is formed is formed in the second conductivity type semiconductor layer 39.

In the photoelectric conversion substrate 20, the first transparent conductive layer 25 on the first conductive type semiconductor layer 37 reflects the unevenness of the second texture structure 82 of the first conductive type semiconductor layer 37, forming a third texture structure 84.
In the photoelectric conversion substrate 20, the second transparent conductive layer 27 on the second conductive type semiconductor layer 39 reflects the unevenness of the second texture structure 83 of the second conductive type semiconductor layer 39, forming a third texture structure 85.

In the photoelectric conversion substrate 20, the transparent conductive layers 25, 27 are not formed over the entire surfaces of the substrate main surfaces 28, 29. When viewed in a plan view, second texture structures 82, 83 are formed on parts of the substrate main surfaces 28, 29, respectively, and third texture structures 84, 85 are formed on the remaining parts of the substrate main surfaces 28, 29, respectively.

(First electrode portion 21)
The first electrode portion 21 is formed by solidifying a first conductive paste, and as shown in FIGS. 2 and 3(a), is composed of a plurality of first collector electrodes 40 (40a to 40d).
As shown in FIGS. 3( a ) and 4 , the first collector electrode 40 constitutes part of the first cell main surface 10 , and is a conductive layer partially laminated on the first substrate main surface 28 of the photoelectric conversion substrate 20 .
The first collector electrode 40 protrudes in the thickness direction relative to the other portion of the first cell main surface 10 (the first substrate main surface 28 of the photoelectric conversion substrate 20 ).
The thickness of the first collector electrode 40 is not particularly limited, but is preferably 5 μm or more and 40 μm or less.

As shown in FIGS. 2 and 3A , the first collector electrode 40 extends in a comb-like shape, and is composed of a first bus bar electrode portion 50 and a plurality of first finger electrode portions 51 .
The first collecting electrode 40 is not particularly limited as long as it has electrical conductivity, and may be made of, for example, a metal material mainly composed of a metal such as gold, silver, aluminum, copper, or palladium, or a metal alloy thereof. The first collecting electrode 40 preferably has a higher electrical conductivity than the first transparent conductive layer 25 that serves as the base.
The first collector electrode 40 in this embodiment is formed simultaneously with the first resin coating portion 23 from the first conductive paste by the first electrode formation process described below, and contains a resin component common to the first resin coating portion 23.
As shown in FIG. 3A, the first collector electrodes 40a to 40d are provided independently and individually, and are not directly connected to each other.

As shown in FIG. 2 , the first bus bar electrode portion 50 is a connection portion that extends in the lateral direction X when viewed in a plan view and connects the ends of the first finger electrode portions 51 together.
The first bus bar electrode portions 50 of the first collector electrodes 40a to 40d are arranged at intervals in the vertical direction Y and are parallel to each other.
In this embodiment, the first bus bar electrode portions 50 of the first collector electrodes 40a to 40d are arranged in parallel at equal intervals in the vertical direction Y.
The width of the first bus bar electrode portion 50 is not particularly limited, but is preferably 0.1 mm or more and 8 mm or less.

The first finger electrode portion 51 is a linear electrode portion extending in the vertical direction Y from a middle portion in the extension direction (horizontal direction X) of the first bus bar electrode portion 50 toward the horizontal side 31 side.
As shown in FIG. 2 , each of the first finger electrode portions 51 extends in the same direction and is arranged side by side at a distance D2 in the horizontal direction X. In this embodiment, each of the first finger electrode portions 51 is arranged side by side at equal intervals in the horizontal direction X at a distance D2 in between.
The width of the first finger electrode portion 51 is narrower than the width of the first bus bar electrode portion 50, and is preferably 20 μm or more and 70 μm or less.
It is preferable that the distance D2 between adjacent first finger electrode portions 51, 51 be 1 mm or less, from the viewpoint of covering the space between the first finger electrode portions 51, 51 with the first resin coating portion 23 by seeping out of the first conductive paste in the first electrode formation process described below.

(Second electrode portion 22)
The second electrode portion 22 is formed by solidifying a second conductive paste, and as shown in FIGS. 2 and 3(b), is composed of a plurality of second collecting electrodes 60 (60a to 60d).
As shown in FIGS. 3( b ) and 4 , the second collector electrode 60 constitutes part of the second cell main surface 11 , and is a conductive layer partially laminated on the second substrate main surface 29 of the photoelectric conversion substrate 20 .
The second collector electrode 60 protrudes in the thickness direction relative to the other portion of the second cell main surface 11 (the second substrate main surface 29 of the photoelectric conversion substrate 20 ).
The thickness of the second collector electrode 60 is not particularly limited, but is preferably 5 μm or more and 40 μm or less.

As shown in FIGS. 2 and 3B , the second collecting electrode 60 extends in a comb-like shape, and is composed of a second bus bar electrode portion 70 and a plurality of second finger electrode portions 71 .
The second collecting electrode 60 is not particularly limited as long as it has conductivity, and may be made of, for example, a metal material mainly composed of a metal such as gold, silver, aluminum, copper, or palladium, or a metal alloy thereof. The second collecting electrode 60 preferably has a higher conductivity than the second transparent conductive layer 27 that serves as the base.
The second collector electrode 60 in this embodiment is formed simultaneously with the second resin coating portion 24 from the second conductive paste by the second electrode formation process described later, and contains a resin component common to the second resin coating portion 24.
As shown in FIG. 3B, the second collecting electrodes 60a to 60d are provided independently and individually, and are not directly connected to each other.

As shown in FIG. 2 , the second bus bar electrode portion 70 is a connection portion that extends in the lateral direction X when viewed in a plan view and connects the ends of the second finger electrode portions 71 together.
The second bus bar electrode portions 70 of the second collector electrodes 60a to 60d are arranged at intervals in the vertical direction Y and are parallel to each other.
In this embodiment, the second bus bar electrode portions 70 of each of the second collector electrodes 60a to 60d are arranged in parallel in the vertical direction Y at equal intervals.
The width of the second bus bar electrode portion 70 is not particularly limited, but is preferably 0.1 mm or more and 8 mm or less.

The second finger electrode portion 71 is a linear electrode portion extending in the vertical direction Y from a middle portion in the horizontal direction X of the second bus bar electrode portion 70 toward the horizontal side 30 side.
As shown in FIG. 2 , each second finger electrode portion 71 extends in the same direction and is arranged side by side at a distance D3 in the horizontal direction X. In this embodiment, each second finger electrode portion 71 is arranged side by side at equal intervals in the horizontal direction X at a distance D3.
The distance D3 between adjacent second finger electrode portions 71, 71 is approximately the same as the distance D2 between adjacent first finger electrode portions 51, 51, and is preferably the same distance.
Here, "substantially the same interval" means that the difference between the interval D2 of the first finger electrode portions 51 and the interval D3 of the second finger electrode portions 71 is 1 μm or less.
The width of the second finger electrode portion 71 is narrower than the width of the second bus bar electrode portion 70, and is preferably not less than 20 μm and not more than 70 μm.
It is preferable that the distance D3 between adjacent second finger electrode portions 71, 71 be 1 mm or less, from the viewpoint of covering the space between the second finger electrode portions 71, 71 with the second resin coating portion 24 by seeping out of the second conductive paste in the second electrode formation process described below.

(First resin coating portion 23)
The first resin coating portion 23 is a layer that protects the first substrate main surface 28 of the photoelectric conversion substrate 20 from physical and mechanical contact with the second electrode portions 22 of the other solar cells 2 when stacked together with other solar cells 2 to form the overlapping structure 1.
The layer also protects the photoelectric conversion substrate 20 from the laser light irradiated in the laser process described below, and suppresses damage to the photoelectric conversion substrate 20 .
The first resin coating portion 23 preferably has gas barrier properties, insulating properties, and light-transmitting properties.
The first resin coating portion 23 in this embodiment is formed by solidifying a resin component containing a liquid resin of the first conductive paste used when forming the first electrode portion 21, and contains a resin component common to the first electrode portion 21. In other words, there is a continuously connected resin portion between the first electrode portion 21 and the first resin coating portion 23.
As shown in FIG. 4 , the first resin coating portion 23 is provided adjacent to the first electrode portion 21 and is continuous with the first electrode portion 21 .
The first resin coating portion 23 spans from the first transparent conductive layer 25 to the exposed portion of the first conductivity type semiconductor layer 37 from the first transparent conductive layer 25, and as shown in Figure 5, it follows and reflects the unevenness of the second texture structure 82 of the underlying first conductivity type semiconductor layer 37 and the third texture structure 84 of the first transparent conductive layer 25, thereby forming an uneven region 86.
Since the uneven region 86 is formed from a resin component that contains a liquid resin having fluidity, the unevenness is smoothed out and the surface unevenness is smaller than the unevenness of the second texture structure 82 and the unevenness of the third texture structure 84.

(Second resin coating portion 24)
The second resin coating portion 24 is a layer that protects the second substrate main surface 29 of the photoelectric conversion substrate 20 from physical and mechanical contact with the first electrode portions 21 of the other solar cells 2 when stacked together with other solar cells 2 to form the overlapping structure 1.
The second resin coating portion 24 preferably has gas barrier properties, insulating properties, and light-transmitting properties.
The second resin coating portion 24 in this embodiment is formed by solidifying a resin component containing a liquid resin of the second conductive paste used when forming the second electrode portion 22, and contains a resin component common to the second electrode portion 22. In other words, there is a continuously connected resin portion between the second electrode portion 22 and the second resin coating portion 24.
As shown in FIG. 4 , the second resin coating portion 24 is provided adjacent to the second electrode portion 22 and is continuous with the second electrode portion 22 .
The second resin coating portion 24 spans from above the second transparent conductive layer 27 to the exposed portion of the second conductivity type semiconductor layer 39 from the second transparent conductive layer 27, and as shown in Figure 5, it follows and reflects the unevenness of the second texture structure 83 of the underlying second conductivity type semiconductor layer 39 and the third texture structure 85 of the second transparent conductive layer 27, thereby forming an uneven region 87.
Since the uneven region 87 is formed from a resin component that contains a liquid resin having fluidity, the unevenness is smoothed out and the surface unevenness is smaller than the unevenness of the second texture structure 83 and the unevenness of the third texture structure 85.

(Solar cell module 100)
As shown in Figures 6 and 7 , the solar cell module 100 is configured such that a group of multiple solar cells 103, each of which has a plurality of divided solar cells 101 electrically connected in series either directly or by a conductive adhesive 102, is sandwiched between a first sealing member 115 and a second sealing member 116, and the space between the first sealing member 115 and the second sealing member 116 is filled and sealed with a first sealing material 117 and a second sealing material 118.
As shown in FIG. 6 , in the solar cell module 100 , the end of each solar cell group 103 in the direction of electrical flow is connected to output wiring 113 , 114 to the outside, and each solar cell group 103 is electrically connected in parallel.

(Segmented solar cell 101)
The divided solar cell 101 is obtained by cutting and dividing the solar cell 2 along the division line L1 shown in FIG.
As shown in Figure 8, the divided solar cell 101 has a first collector electrode 40 and a first resin coating portion 23 provided on the first substrate main surface 28 of the photoelectric conversion substrate 20, and a second collector electrode 60 and a second resin coating portion 24 provided on the second substrate main surface 29.
Each divided solar cell 101 has a laser cut portion 120 on its widthwise end face, which is the cut surface, and a crease cut portion 121 on which a crease mark is formed.
The laser cut portion 120 is continuous with the cut portion 121 and forms an inclined surface inclined with respect to the cut portion 121, and a protective resin layer 122 is formed on the surface.
The photoelectric conversion substrate 20 of the divided solar cell 101 has a width in the vertical direction Y and extends in the horizontal direction X when viewed in a plan view.
The protective resin layer 122 is continuous with the first resin-coated portion 23 and contains an oxide component of the resin component contained in the first resin-coated portion 23 .

(Conductive adhesive 102)
The conductive adhesive 102 is a conductive member having electrical conductivity, and is an adhesive that connects the bus bar electrode portions 50, 70 of the divided solar cells 101, 101 together, as shown in FIG.
The conductive adhesive 102 of this embodiment is a conductive adhesive film in which a conductive adhesive material is provided on both sides of a conductive film.

(Sealing members 115, 116)
The sealing members 115 and 116 are insulating sealing substrates that extend in a planar shape and have sealing and insulating properties.
At least the sealing member 115 on the light receiving side is a light-transmitting member that is capable of transmitting light in the thickness direction.

(Sealing materials 117, 118)
The sealing materials 117 and 118 have sealing properties and serve to seal the solar cell group 103 together with the sealing members 115 and 116 , and also serve as an adhesive that bonds the sealing members 115 and 116 together.

Next, we will explain the positional relationship of each part of the solar cell 2 in this embodiment.

As shown in Figure 2, when the photoelectric conversion substrate 20 is viewed in a plane, the solar cell 2 has a second collecting electrode 60 located between the first collecting electrodes 40, 40 adjacent to each other in the vertical direction Y, and the first collecting electrode 40 located between the second collecting electrodes 60, 60 adjacent to each other in the vertical direction Y.
The first bus bar electrode portions 50 of the first collector electrodes 40a to 40c extend in parallel to and in close proximity to the second bus bar electrode portions 70 of the adjacent second collector electrodes 60b to 60d.
Between the first bus bar electrode portion 50 and the second bus bar electrode portion 70 that are closest to each other in the vertical direction Y, a cutting region is provided for dividing the divided solar cell 101 .
From the viewpoint of ease of dividing the solar cell 2, the distance D1 (the width of the cutting area) between the first bus bar electrode portion 50 and the second bus bar electrode portion 70 adjacent to each other on either side of the dividing line L1 shown in FIG. 2 is preferably 0.5 mm or more and 4 mm or less.
As shown in FIG. 4A , the first bus bar electrode portions 50 of each first collector 40 are shifted in the vertical direction Y with respect to the second bus bar electrode portions 70 of each second collector 60, and do not overlap in the thickness direction.

When the photoelectric conversion substrate 20 is viewed in a plan view as shown in Figure 2, the first finger electrode portion 51 of the first collecting electrode 40 extends in the opposite direction to the second finger electrode portion 71 of the second collecting electrode 60, and the tip of the first finger electrode portion 51 in the extension direction reaches the vicinity of the opposing second collecting electrode 60.
The first finger electrode portion 51 extends from the first bus bar electrode portion 50 between adjacent second finger electrode portions 71, 71 in the lateral direction X, and the second finger electrode portion 71 extends from the second bus bar electrode portion 70 between adjacent first finger electrode portions 51, 51 in the lateral direction X.

As shown in FIG. 4B , the first finger electrode portions 51 of each first collector 40 are shifted in the lateral direction X relative to the second finger electrode portions 71 of each second collector 60 and do not overlap in the thickness direction.
Each first finger electrode portion 51 is located between adjacent second finger electrode portions 71 , 71 in the horizontal direction X, and is preferably located in the center between the adjacent second finger electrode portions 71 , 71 .
Each second finger electrode portion 71 is located between adjacent first finger electrode portions 51 , 51 in the horizontal direction X, and is preferably located in the center between the adjacent first finger electrode portions 51 , 51 .

As shown in Figure 5, the first cell main surface 10 of the solar cell 2 has a first inner edge region 130 formed by a first electrode portion 21 and a first resin coating portion 23, and the edge of the first inner edge region 130 is formed within a range of 0.5 mm from the outer peripheral edge of the solar cell 2.
In the first inner edge region 130 , the total area of the first resin coating portion 23 is preferably larger than the total area of the first electrode portion 21 .
In the first inner edge region 130 of the first cell main surface 10, the space between adjacent first busbar electrode portions 50, 50 is defined by a first resin coating portion 23, and the space between adjacent first finger electrode portions 51, 51 is also defined by a first resin coating portion 23.
The area of the first inner edge region 130 is larger than the area of the first transparent conductive layer 25, and the first resin coating 23 covers the end faces of the first transparent conductive layer 25 as shown in FIG. 5(a).

Similarly, the second cell main surface 11 of the solar cell 2 has a second inner edge region 131 formed by the second electrode portion 22 and the second resin coating portion 24, and the edge of the second inner edge region 131 is formed within a range of 0.5 mm from the outer peripheral edge of the solar cell 2.
In the second inner edge region 131 , the total area of the second resin coating portion 24 is preferably larger than the total area of the second electrode portion 22 .
In the second inner edge region 131 of the second cell main surface 11, the space between adjacent second busbar electrode portions 70, 70 is defined by a second resin coating portion 24, and the space between adjacent second finger electrode portions 71, 71 is also defined by a second resin coating portion 24.
The area of the second inner edge region 131 is larger than the area of the second transparent conductive layer 27, and the second resin coating portion 24 covers the end face of the second transparent conductive layer 27 as shown in FIG. 5(a).

Next, a method for manufacturing the solar cell module 100 of this embodiment will be described.

The manufacturing method for the solar cell module 100 is carried out across the first and second manufacturing lines, and is comprised of a solar cell manufacturing process, a superimposed structure forming process, a transport process, and a solar cell processing process.

(Solar cell manufacturing process)
The solar cell manufacturing process is a process for forming solar cells 2 on a first production line.
In the solar cell manufacturing process, first, both surfaces of the semiconductor substrate 35 are etched by anisotropic alkaline wet etching, and first texture structures 80, 81 are formed on the surface. Next, a plasma CVD device or the like is used to stack a first intrinsic semiconductor layer 36 and a first conductivity type semiconductor layer 37 in this order on one main surface of the semiconductor substrate 35, and a second intrinsic semiconductor layer 38 and a second conductivity type semiconductor layer 39 in this order on the other main surface of the semiconductor substrate 35, as shown in FIG. 9( a), to form the photoelectric conversion section 26 (photoelectric conversion section formation process).

Next, as shown in FIG. 9(b), transparent conductive layers 25 and 27 are formed on one main surface side and the other main surface side of the photoelectric conversion section 26 using a sputtering device or the like, thereby forming the photoelectric conversion substrate 20 (transparent conductive layer formation process).

At this time, when the photoelectric conversion substrate 20 is viewed in a plane, the transparent conductive layers 25, 27 are formed on most of the substrate main surfaces 28, 29, and transparent conductive layer non-forming areas 133, 134 where the transparent conductive layers 25, 27 are not formed are formed along the outer periphery of the substrate main surfaces 28, 29.
That is, the transparent conductive layer- free regions 133 and 134 are exposed portions of the photoelectric conversion section 26 from the transparent conductive layers 25 and 27 provided on the outer periphery of the photoelectric conversion substrate 20 when viewed in plan.

Next, a first conductive paste containing conductive particles and liquid resin is applied by screen printing or the like onto the first transparent conductive layer 25 constituting the first substrate main surface 28 of the photoelectric conversion substrate 20, as shown in Figure 10 (a).Due to their high density, the conductive particles remain at the intended position for forming the first electrode portion 21, while the liquid resin seeps out further from the intended position for forming the first electrode portion 21.
That is, conductive particles aggregate at the position where the first electrode portion 21 is planned to be formed, and the gaps between the conductive particles contain liquid resin, while the liquid resin seeps out near the position where the first electrode portion 21 is planned to be formed.
Then, with the liquid resin of this second conductive paste seeping out from the intended position where the first electrode portion 21 is to be formed (the portion applied to the photoelectric conversion substrate 20), the first conductive paste is solidified by heating or the like, and the first electrode portion 21 and the first resin coating portion 23 are formed (first electrode formation process).
That is, in the first electrode formation process, a liquid component containing a liquid resin seeps out from the applied portion of the first conductive paste where the first electrode portion 21 is formed into the gap of the first electrode portion 21 to form the first resin coating portion 23.

The first electrode portion 21 and the first resin-coated portion 23 formed in this first electrode formation process contain a common resin component. That is, there is a continuously connected resin portion between the first electrode portion 21 and the first resin-coated portion 23. More specifically, a continuously connected resin portion is formed between the first resin-coated portion 23 and a part of the resin in the gaps between the conductive particles constituting the first electrode portion 21.
The conductive particles used in the first conductive paste are not particularly limited as long as they are conductive particles. For example, metal materials such as silver, aluminum, copper, indium, bismuth, and gallium can be used as the conductive particles.
The liquid resin used in the first conductive paste is not particularly limited as long as it is a binder resin in a liquid state and is solidified by heat, ultraviolet light, etc. As the liquid resin, for example, a thermosetting resin such as an epoxy resin, a phenol resin, or an acrylic resin can be used.
The first conductive paste may further contain a liquid solvent such as an organic solvent or an inorganic solvent.
The first conductive paste of the present embodiment is a mixture containing conductive particles, a liquid resin, and a liquid solvent.

In this first electrode formation process, as shown in Figure 10 (a), a first inner edge region 130 is formed, and this first inner edge region 130 overlaps with a first transparent conductive layer non-forming region 133, and the first electrode portion 21 and the first resin coating portion 23 cover the entire first transparent conductive layer 25, and further the first resin coating portion 23 extends from above the first transparent conductive layer 25 to the first transparent conductive layer non-forming region 133.
That is, the first resin coating portion 23 is provided spanning from the first transparent conductive layer 25 to the exposed portion of the photoelectric conversion portion 26, and the outer peripheral edge of the first inner edge region 130 is formed outside the outer peripheral edge of the first transparent conductive layer 25 and inside the outer peripheral edge of the photoelectric conversion substrate 20.

Next, a second conductive paste containing conductive particles and liquid resin is applied by screen printing or the like onto the second transparent conductive layer 27 constituting the second substrate main surface 29 of the photoelectric conversion substrate 20, as shown in Figure 10 (b).Due to the high density of the conductive particles, the conductive particles remain at the intended position for forming the second electrode portion 22, while the liquid resin seeps out further from the intended position for forming the second electrode portion 22.
That is, conductive particles aggregate at the position where the second electrode portion 22 is planned to be formed, and the gaps between the conductive particles contain liquid resin, while the liquid resin seeps out near the position where the second electrode portion 22 is planned to be formed.
Then, with the liquid resin of this second conductive paste seeping out from the intended position where the second electrode portion 22 is to be formed (the portion applied to the photoelectric conversion substrate 20), the second conductive paste is solidified by heating or the like, and the second electrode portion 22 and the second resin coating portion 24 are formed (second electrode formation process).
That is, in the second electrode formation process, liquid components containing liquid resin seep out from the applied portion of the second conductive paste where the second electrode portion 22 is formed into the gaps of the second electrode portion 22 to form the second resin coating portion 24.

The second electrode portion 22 and the second resin-coated portion 24 formed in this second electrode formation process contain a common resin component. That is, there is a continuously connected resin portion between the second electrode portion 22 and the second resin-coated portion 24. More specifically, a continuously connected resin portion is formed between the second resin-coated portion 24 and a part of the resin in the gaps between the conductive particles constituting the second electrode portion 22.
The second conductive paste may contain the same conductive particles and liquid resin as the first conductive paste used in the first electrode formation step.
The second conductive paste of the present embodiment is a mixture containing conductive particles, a liquid resin, and a liquid solvent.

In this second electrode formation process, as shown in Figure 10 (b), a second inner edge region 131 is formed, and this second inner edge region 131 overlaps with the second transparent conductive layer non-forming region 134, and the second electrode portion 22 and the second resin coating portion 24 cover the entire second transparent conductive layer 27, and further, the second resin coating portion 24 extends from above the second transparent conductive layer 27 to the second transparent conductive layer non-forming region 134.
That is, the second resin coating portion 24 is provided spanning from the second transparent conductive layer 27 to the exposed portion of the photoelectric conversion portion 26, and the outer peripheral edge of the second inner edge region 131 is formed outside the outer peripheral edge of the second transparent conductive layer 27 and inside the outer peripheral edge of the photoelectric conversion substrate 20.

Once the first electrode formation process and the second electrode formation process are completed, the solar cell 2 is completed and the solar cell manufacturing process is completed.

(Superimposed structure forming process)
The overlapping structure forming step is a step of forming the overlapping structure 1 in order to transport the solar cell 2 from the first production line to the second production line in the transport step.
In the overlapping structure forming step, first, as shown in FIG. 1 , a plurality of solar cells 2 are overlapped in the vertical direction Z, and the solar cells 2 are overlapped in the thickness direction to form the overlapping structure 1 .

In this case, if we look at the three rows of solar cells 2A to 2C stacked in the thickness direction as shown in Figure 11, the first cell principal surface 10 of each of the solar cells 2A to 2C forms the upper surface, and the second cell principal surface 11 forms the lower surface.
As shown in Figure 11, the second electrode portion 22 on the second cell main surface 11 of the middle solar cell 2B (first solar cell) is supported in contact with the first resin coating portion 23 on the first cell main surface 10 of the lower solar cell 2A, and the first electrode portion 21 on the first cell main surface 10 is supported in contact with the second resin coating portion 24 on the second cell main surface 11 of the upper solar cell 2C (second solar cell).
The middle solar cell 2B is supported by the first electrode portion 21 of the lower solar cell 2A in contact with the second resin coating portion 24 of the second cell main surface 11, and is supported by the second electrode portion 22 of the upper solar cell 2C in contact with the first resin coating portion 23 of the first cell main surface 10.

(Transportation process)
The transport step is a step of transporting the overlapped structure 1 formed in the overlapped structure forming step from the first production line to the second production line.

(Solar cell processing process)
The solar cell processing step is a step in which solar cells are processed in the second production line to form the solar cell module 100 .
In the solar cell processing step, first, the solar cell 2 is removed from the overlapping structure 1 formed in the overlapping structure forming step, and cut along the dividing lines L1 shown in Figure 2 to divide it into a plurality of divided solar cells 101 (dividing step).

Specifically, as shown in FIG. 12(a), a laser beam is irradiated from the first cell main surface 10 of the solar cell 2 so as to pass through the positions overlapping the resin coating portions 23, 24 in a plan view while avoiding the electrode portions 21, 22, to form a dividing groove 125 that extends from the first resin coating portion 23 to at least the inside of the semiconductor substrate 35 (the middle portion in the thickness direction) (dividing groove forming process).

At this time, a portion of the first resin coating portion 23 is oxidized by the laser light, and a protective resin layer 122 is formed on the surface of the dividing groove 125.

Next, as shown in FIG. 12(b), the solar cell 2 is folded along the dividing groove 125 so as to pass through the second resin coating portion 24, and divided into a plurality of divided solar cell units 101 (folding and dividing process).

At this time, the sheet is cut in the thickness direction from the bottom of the dividing groove 125, forming the laser cut portion 120 and the crease cut portion 121.

Next, as shown in FIG. 7, the first busbar electrode portion 50 and the second busbar electrode portion 70 of each divided solar cell 101 are bonded with a conductive adhesive 102 to form a solar cell group 103 in which the divided solar cell cells 101 are electrically connected in series (solar cell group formation process).

Next, as shown in FIG. 6, the busbar electrode portions 50, 70 at the ends of each solar cell group 103 in the direction of electrical flow are connected to the output wiring 113, 114, respectively (wiring connection process).

Next, as shown in FIG. 7, each solar cell group 103 is sandwiched between sealing members 115, 116, and the spaces between each solar cell group 103 and the sealing members 115, 116 are filled with sealing materials 117, 118 to seal, completing the solar cell module 100 (assembly process).

According to the solar cell 2 of this embodiment, when the second cell main surface 11 of the upper solar cell 2 is stacked on the first cell main surface 10, most of the second electrode portion 22 of the upper solar cell 2 can be supported by the first resin coating portion 23, thereby reducing damage such as scratches caused by the second electrode portion 22 of the upper solar cell 2 coming into contact with the first substrate main surface 28 of the photoelectric conversion substrate 20.
Furthermore, according to the solar cell 2 of this embodiment, when the second cell main surface 11 is stacked on the first cell main surface 10 of the solar cell 2 in the lower tier, most of the first electrode portion 21 of the solar cell 2 in the lower tier can be supported by the second resin coating portion 24, thereby reducing damage such as scratches caused by the first electrode portion 21 of the solar cell 2 in the lower tier coming into contact with the second substrate main surface 29 of the photoelectric conversion substrate 20.

In the solar cell 2 of this embodiment, the first electrode portion 21 is adjacent to the first resin coating portion 23 and contains a resin component common to the first resin coating portion 23, so they can be formed simultaneously with the first conductive paste. Similarly, the second electrode portion 22 is adjacent to the second resin coating portion 24 and contains a resin component common to the second resin coating portion 24, so they can be formed simultaneously with the second conductive paste.

According to the solar cell 2 of this embodiment, the first finger electrode portion 51, which is thinner than the first bus bar electrode portion 50 and more likely to be cut by a load, overlaps the second resin coating portion 24 in a plan view, so that when the second cell main surface 11 of the solar cell 2 in the upper layer is stacked on the first cell main surface 10, the first finger electrode portion 51 comes into contact with the second resin coating portion 24 of the solar cell 2 in the upper layer, and the second resin coating portion 24 functions as a buffer material. Therefore, the first finger electrode portion 51 is not easily cut.
Furthermore, according to the solar cell 2 of this embodiment, the second finger electrode portion 71, which is thinner than the second bus bar electrode portion 70 and more likely to be cut by a load, overlaps the first resin coating portion 23 in a plan view, so that when the second cell main surface 11 of the upper solar cell 2 is stacked on the first cell main surface 10 of the lower solar cell 2, the second finger electrode portion 71 comes into contact with the first resin coating portion 23 of the lower solar cell 2, and the first resin coating portion 23 functions as a buffer material. Therefore, the second finger electrode portion 71 is not easily cut.

According to the manufacturing method of the solar cell 2 of this embodiment, the first electrode portion 21 and the first resin coating portion 23 can be formed simultaneously using the first conductive paste, and can be easily manufactured. Similarly, the second electrode portion 22 and the second resin coating portion 24 can be formed simultaneously using the second conductive paste, and can be easily manufactured.

According to the solar cell 2 of this embodiment, the first inner edge region 130 formed within a range of 0.5 mm from the outer peripheral edge on the first cell main surface 10 is composed of the first electrode portion 21 and the first resin coating portion 23, thereby preventing moisture and the like from entering in the thickness direction from the first cell main surface 10.
Furthermore, according to the solar cell 2 of this embodiment, the second inner edge region 131 formed within a range of 0.5 mm from the outer peripheral edge on the second cell main surface 11 is composed of the second electrode portion 22 and the second resin coating portion 24, so that the intrusion of moisture and the like in the thickness direction from the second cell main surface 11 can be suppressed.

In the solar cell 2 of this embodiment, the electrode portions 21, 22 and the resin coating portions 23, 24 include a resin portion that is continuously connected, so that moisture and the like can be prevented from entering through the gaps between the electrode portions 21, 22 and the resin coating portions 23, 24.

In the solar cell 2 of this embodiment, the total area of the resin-coated portions 23, 24 of the inner edge regions 130, 131 is larger than the total area of the electrode portions 21, 22, so that a large light-receiving area can be secured while preventing the intrusion of moisture, etc.

In the solar cell 2 of this embodiment, the first inner edge region 130 has the first resin coating portion 23 between adjacent first finger electrode portions 51, 51, so that the intrusion of moisture and the like can be more effectively prevented.
Furthermore, in the solar cell 2 of this embodiment, the second inner edge region 131 has the second resin coating portion 24 between adjacent second finger electrode portions 71, 71, which further prevents the intrusion of moisture and the like.

In the solar cell 2 of this embodiment, the resin coating portions 23, 24 have uneven regions 86, 87 with unevenness smaller than the unevenness of the second texture structures 82, 83 and the unevenness of the third texture structures 84, 85. This reduces the wettability near the electrode portions 21, 22, and prevents the conductive adhesive 102 from spreading even if the conductive adhesive 102 protrudes from the electrode portions 21, 22 during the solar cell group formation process.

In the solar cell 2 of this embodiment, the pn junction is protected by the first electrode portion 21 and the first resin coating portion 23, so the pn junction is less susceptible to moisture intrusion and mechanical contact.

In the solar cell 2 of this embodiment, the inner edge regions 130, 131 are composed of the electrode portions 21, 22 and the resin coating portions 23, 24, so that even if the transparent conductive layers 25, 27 are interposed between the photoelectric conversion portion 26, the intrusion of moisture and the like into the photoelectric conversion portion 26 can be suppressed.

In the solar cell 2 of this embodiment, the resin coating portions 23, 24 cover the transparent conductive layers 25, 27 along the outer periphery of the transparent conductive layers 25, 27, and extend from the transparent conductive layers 25, 27 to the transparent conductive layer non-forming regions 133, 134. In other words, because the resin coating portions 23, 24 cover the end faces of the transparent conductive layers 25, 27, it is possible to suppress the intrusion of moisture and the like toward the interface between the photoelectric conversion portion 26 and the transparent conductive layers 25, 27.

According to the manufacturing method of the divided solar cell 101 of this embodiment, the portion of the photoelectric conversion substrate 20 where the division groove 125 is formed is protected by the first resin coating portion 23, so that the impact on the photoelectric conversion substrate 20 when forming the division groove 125 can be suppressed.

In the manufacturing method of the split solar cell 101 of this embodiment, the portion of the photoelectric conversion substrate 20 that is to be folded is protected by the second resin coating portion 24, so that the impact on the photoelectric conversion substrate 20 when folding can be suppressed.

In the split solar cell 101 of this embodiment, a protective resin layer 122 is formed on part of the end face of the photoelectric conversion substrate 20, making it less likely for short circuits to occur at the end face of the photoelectric conversion substrate 20, and therefore highly reliable.

In the solar cell 2 of this embodiment, the first electrode portion 21 and the second electrode portion 22 do not overlap when viewed in a plan view, so when the solar cell 2 is stacked with other solar cells 2, defects such as chipping or cracking caused by the electrode portions 21, 22 coming into contact with each other can be prevented.

In the solar cell 2 of this embodiment, when viewed in a plan view, the first finger electrode portion 51 and the second finger electrode portion 71 extend in opposite directions between the first bus bar electrode portion 50 and the second bus bar electrode portion 70. Therefore, when multiple solar cells 2 are stacked, the load is evenly distributed across the surface of the solar cell 2, making it more stable.

In the solar cell 2 of this embodiment, when viewed in a plan view, the first finger electrode portion 51 is positioned and extends between the second finger electrode portions 71, 71 adjacent to each other in the horizontal direction X, and the second finger electrode portion 71 is positioned and extends between the first finger electrode portions 51, 51 adjacent to each other in the horizontal direction X. Therefore, when multiple solar cells 2 are stacked, the load is evenly distributed across the surface of the solar cell 2, making it more stable.

In the solar cell 2 of this embodiment, the second collector 60b is located between the mutually independent first collectors 40a, 40b, and the first collector 40a is located between the mutually independent second collectors 60a, 60b. Therefore, even if the solar cell 2 is cut between the first collector 40a and the second collector 60b, power can be extracted from the first collector 40a (40b) and the second collector 60a (60b) in each of the cut solar cell segments 101.

According to the stacked structure 1 of this embodiment, the first electrode portion 21 of the lower solar cell 2B and the second electrode portion 22 of the upper solar cell 2C are not in contact with each other, so defects such as chipping and cracking caused by contact between the electrodes 21, 22 can be prevented.

In the above embodiment, the solar cells 2 are laid down and stacked in the vertical direction Z, but the present invention is not limited to this. The solar cells 2 may be stood upright and stacked in a direction intersecting the vertical direction Z.

In the above embodiment, multiple solar cells 2 are stacked, but the present invention is not limited to this. Multiple divided solar cells 101 may also be stacked.

In the above embodiment, one solar cell 2 is divided into four divided solar cells 101, but the present invention is not limited to this. One solar cell 2 may be divided into two to three divided solar cells 101, or into five or more divided solar cells 101. In this case, the number of collector electrodes 40, 60 will be increased or decreased depending on the number of divided solar cells 101 to be divided.

In the above embodiment, the solar cell 2 is divided into a plurality of divided solar cell cells 101, but the present invention is not limited to this. The solar cell 2 does not have to be divided.

In the above embodiment, the second electrode formation process is performed after the first electrode formation process, but the present invention is not limited to this. The first electrode formation process may be performed after the second electrode formation process.

In the above embodiment, the pn junction is provided on the first cell main surface 10 side with respect to the semiconductor substrate 35, but the present invention is not limited to this. The pn junction may be provided on the second cell main surface 11 side with respect to the semiconductor substrate 35.

In the above embodiment, each electrode portion 21, 22 has a busbar electrode portion 50, 70 and a finger electrode portion 51, 71, but the present invention is not limited to this. It may also be a so-called busbarless solar cell that does not have a busbar electrode.

In the above embodiment, the first finger electrode portions 51 are arranged side by side at equal intervals, but the present invention is not limited to this. The first finger electrode portions 51 may also be arranged at non-equidistant intervals. Similarly, in the above embodiment, the second finger electrode portions 71 are arranged side by side at equal intervals, but the present invention is not limited to this. The second finger electrode portions 71 may also be arranged at non-equidistant intervals.

In the above embodiment, the spacing D2 between the first finger electrode portions 51 and the spacing D3 between the second finger electrode portions 71 are substantially the same, but the present invention is not limited to this. The spacing D2 between the first finger electrode portions 51 may be narrower than the spacing D3 between the second finger electrode portions 71, and the spacing D3 between the second finger electrode portions 71 may be narrower than the spacing D2 between the first finger electrode portions 51.
13(a), the plurality of first finger electrode portions 51 may be located between adjacent second finger electrode portions 71, 71 in the horizontal direction X. Also, the plurality of second finger electrode portions 71 may be located between adjacent first finger electrode portions 51, 51 in the horizontal direction X.
For example, as shown in FIG. 13( a), in the case where a plurality of first finger electrode portions 51 are arranged side by side at equal intervals of a distance D2, and a plurality of second finger electrode portions 71 are arranged side by side at equal intervals of a distance D2/n (n is a natural number greater than or equal to 2), each first finger electrode portion 51 may be located at the center of adjacent second finger electrode portions 71, 71 in the horizontal direction X, and n second finger electrode portions 71 may be located between adjacent first finger electrode portions 51, 51.
Also, for example, as shown in FIG. 13 (b), in the case where a plurality of second finger electrode portions 71 are arranged side by side at equal intervals of a distance D3, and a plurality of first finger electrode portions 51 are arranged side by side at equal intervals of a distance D3/n (n is a natural number greater than or equal to 2), each second finger electrode portion 71 may be located at the center of adjacent first finger electrode portions 51, 51 in the horizontal direction X, and n first finger electrode portions 51 may be located between adjacent second finger electrode portions 71, 71.

In the above embodiment, the solar cell 2 has the electrodes 21, 22 arranged at intervals in the vertical direction Y, but the present invention is not limited to this. The solar cell 2 may have the electrodes 21, 22 arranged in the horizontal direction X.

In the above embodiment, the solar cell 2 is a crystalline solar cell and a heterojunction solar cell, but the present invention is not limited to this. The solar cell 2 may be another type of solar cell. For example, it may be a PERC type solar cell.

In the above embodiment, the resin coating portions 23, 24 are formed on both substrate main surfaces 28, 29 of the photoelectric conversion substrate 20, but the present invention is not limited to this. The resin coating portion 23 (resin coating portion 24) may be coated on only one substrate main surface 28 (substrate main surface 29) of the two substrate main surfaces 28, 29 of the photoelectric conversion substrate 20.

In the above embodiment, the resin coating portions 23, 24 are formed on both the first substrate main surface 28 side and the second substrate main surface 29 side of the photoelectric conversion substrate 20, but the present invention is not limited to this. The resin coating portion 23 (resin coating portion 24) may be formed only on one substrate main surface 28 (substrate main surface 29) side of the photoelectric conversion substrate 20.

In the above embodiment, when the photoelectric conversion substrate 20 is viewed in plan, the solar cell 2 has the first electrode portion 21 entirely overlapped with the second resin coating portion 24, but the present invention is not limited to this. The first electrode portion 21 may overlap most of the second resin coating portion 24, and the remaining portion may overlap with the second electrode portion 22.
Similarly, in the solar cell 2, when the photoelectric conversion substrate 20 is viewed in plan, the entire second electrode portion 22 overlaps with the first resin coating portion 23, but the present invention is not limited to this. The second electrode portion 22 may overlap with the first resin coating portion 23 for the most part, and overlap with the first electrode portion 21 for the remaining part.

In the above embodiment, in the overlapping structure 1, both the busbar electrode portions 50, 70 and the finger electrode portions 51, 71 are in contact with the resin coating portions 24, 23, but the present invention is not limited to this. The busbar electrode portions 50, 70 do not have to be in contact with the resin coating portions 24, 23. In other words, the resin coating portions 24, 23 do not have to be provided at positions corresponding to the busbar electrode portions 50, 70, and the busbar electrode portions 50, 70 may be in contact with each other. In addition, the tip portion of the first finger electrode portion 51 of the lower solar cell 2B may be in contact with the second busbar electrode portion 70 of the upper solar cell 2C.

In the above embodiment, the thickness of the first electrode portion 21 and the thickness of the second electrode portion 22 are approximately the same, but the present invention is not limited to this. The thickness of the first electrode portion 21 may be greater than the thickness of the second electrode portion 22. In that case, in the overlapping structure as shown in FIG. 11, the first electrode portion 21 of the first cell main surface 10 of the middle solar cell 2B (first solar cell) contacts the second resin coating portion 24 of the second cell main surface 11 of the upper solar cell 2C (second solar cell) to support the solar cell 2C. The middle solar cell 2B is also supported by the first electrode portion 21 of the lower solar cell 2A contacting the second resin coating portion 24 of the second cell main surface 11.

In the above embodiment, the thickness of the first electrode portion 21 and the thickness of the second electrode portion 22 are approximately the same, but the present invention is not limited to this. The thickness of the second electrode portion 22 may be greater than the thickness of the first electrode portion 21. In that case, in the overlapping structure as shown in FIG. 11, the middle solar cell 2B (first solar cell) is supported by the second electrode portion 22 of the second cell main surface 11 contacting the first resin coating portion 23 of the first cell main surface 10 of the lower solar cell 2A. The middle solar cell 2B is also supported by the second electrode portion 22 of the upper solar cell 2C contacting the first resin coating portion 23 of the first cell main surface 10.

In the above embodiment, the dividing groove 125 is formed by irradiating with laser light, but the present invention is not limited to this. The dividing groove 125 may be formed by other methods such as a dicing saw.

In the embodiment described above, in the dividing step, a laser beam is irradiated from the first cell main surface 10 side to form dividing grooves 125, and the solar cell is folded along the dividing grooves 125 to divide into a plurality of divided solar cell cells 101, but the present invention is not limited to this. In the dividing step, a laser beam may be irradiated from the second cell main surface 11 side to form dividing grooves 125 as shown in Fig. 14(a), and the solar cell may be folded along the dividing grooves 125 to divide into a plurality of divided solar cell cells 101 as shown in Fig. 14(b).
Furthermore, in the dividing step, laser light may be applied to form dividing grooves 125 that reach the entire thickness direction of the solar cell 2, thereby dividing the solar cell into a plurality of divided solar cell 101. That is, the solar cell may be divided into a plurality of divided solar cell 101 only by the laser step. In this case, the laser light may be applied from the first cell main surface 10 side, or from the second cell main surface 11 side. In this case, the protective resin layer 122 is formed on the entire end face of the photoelectric conversion substrate 20.

The above embodiments can be freely substituted or added to each component as long as they fall within the technical scope of the present invention.

2, 2A to 2C Solar cell 10 First cell main surface (first main surface)
11 Second cell principal surface (second principal surface)
20 Photoelectric conversion substrate 21 First electrode portion 22 Second electrode portion 23 First resin coated portion 24 Second resin coated portion 25 First transparent conductive layer 26 Photoelectric conversion portion 27 Second transparent conductive layer 28 First substrate main surface 29 Second substrate main surface 51 First finger electrode portion 71 Second finger electrode portion 82, 83 Second texture structure 84, 85 Third texture structure 86, 87 Roughness region 130 First inner edge region 131 Second inner edge region 133 First transparent conductive layer non-formed region 134 Second transparent conductive layer non-formed region

Claims (10)

1. A first electrode portion and a resin coating portion adjacent to the first electrode portion,
   the first electrode portion and the resin coating portion constitute a part of a first main surface,
   the first main surface has an inner edge region constituted by the first electrode portion and the resin coating portion,
   A solar cell, wherein the edge of the inner edge region is formed within a range of 0.5 mm from the outer edge.
2. The solar cell according to claim 1, wherein the first electrode portion and the resin coating portion include a resin portion that is continuously connected.
3. The solar cell according to claim 1 or 2, wherein the total area of the resin-coated portion of the inner edge region is greater than the total area of the first electrode portion.
4. The first electrode portion has at least two finger electrode portions,
   The two finger electrode portions extend substantially parallel to each other and are arranged side by side at an interval in a direction intersecting the extending direction,
   The solar cell according to claim 1 , wherein the inner edge region is formed of the resin coating portion between the two finger electrode portions.
5. the first electrode portion and the resin coating portion are formed on a first substrate main surface of a photoelectric conversion substrate,
   the photoelectric conversion substrate has a textured structure formed on the first substrate main surface,
   The solar cell according to claim 1 , wherein the resin-coated portion has an uneven region in which unevenness is smaller than unevenness of the textured structure.
6. The solar cell according to claim 5, wherein the resin coating portion covers the unevenness of the textured structure to form the uneven area.
7. the first electrode portion and the resin coating portion are formed on a first substrate main surface of a photoelectric conversion substrate,
   the photoelectric conversion substrate has a pn junction,
   The solar cell according to claim 1 , wherein the pn junction is formed closer to the first main surface than a center in a thickness direction of the photoelectric conversion substrate.
8. a transparent conductive layer is disposed at a position overlapping with the inner edge region in a plan view;
   The solar cell according to claim 1 , wherein the first electrode portion and the resin coating portion cover the transparent conductive layer.
9. the first electrode unit is laminated on a transparent conductive layer,
   the first main surface has a transparent conductive layer-free region where no transparent conductive layer is formed,
   The solar cell according to claim 8 , wherein the resin coating portion coats the transparent conductive layer along an outer periphery of the transparent conductive layer and extends from the transparent conductive layer to the region where the transparent conductive layer is not formed.
10. A photoelectric conversion substrate having a photoelectric conversion unit and a transparent conductive layer, a first electrode unit formed on the transparent conductive layer, and a resin coating unit adjacent to the first electrode unit,
    the photoelectric conversion unit has an exposed portion at an outer periphery thereof which is not exposed from the transparent conductive layer when viewed in a plan view,
    The resin coating portion coats the transparent conductive layer along an outer periphery of the transparent conductive layer and is provided across from the transparent conductive layer to the exposed portion of the photoelectric conversion portion.

Images