JP2014232774A - Solar cell module manufacturing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a solar cell module manufacturing device suppressing a deviation with a rear face power collection electrode produced by a curvature and a meander of a tab, so as not to generate reduced junction intensity and power collection loss.SOLUTION: The solar cell manufacturing device includes: a wall part 12a having a variable height and disposed on a junction stage 13; and a tab correction gauge 12 for restricting the curvature of a part of a tab 34b, protruding outside a solar cell element 1a, by the wall part 12a from the side. The height of the wall part 12a is varied between a first height, which is higher than or same as the height of a light-receiving plane of the solar cell element 1a on the junction stage 13, and a second height which is lower than or same as the height of the top face of the tab 34b contacting to the junction stage 13, while a solar cell element transfer mechanism 14 bends the tab 34b.

Description

  The present invention relates to a solar cell module manufacturing apparatus.

  Patent Document 1 discloses a solar cell in which solar cell elements are connected in series by sequentially connecting a plurality of solar cell elements having a surface electrode formed on the front surface and a back surface collecting electrode formed on the back surface by a plurality of tabs. An apparatus and method for manufacturing a battery module is disclosed.

  Specifically, the solar cell element to be processed is arranged so that the back surface collecting electrode overlaps one of the tabs. Next, another tab is disposed so as to overlap the surface electrode of the solar cell element to be processed. Arrangement of other tabs on the surface electrode is performed by a tab adsorber for adsorbing and holding the tabs. And, by pressing and heating the other tabs superimposed on the surface electrode of the solar cell element to be processed by the pressing mechanism, the other tabs and the surface electrode are welded by the solder supplied in advance to the tabs, And one of the tabs and the back electrode are welded.

  By repeating the above steps, a string in which a plurality of solar cell elements are connected in series is manufactured. The formed string is carried out to another stage, and a solar cell module is manufactured by electrically connecting a predetermined number of strings in parallel.

  The tab used for the connection of the solar cell element is wound up in a roll shape, and the pulled-out tab has a curl. Due to this curl, there is a problem that the tabs are bent or meandered when arranged on the back collector electrode or the front electrode of the solar cell element, and the electrode of the solar cell element and the tab are displaced.

  Japanese Patent Application Laid-Open No. 2005-228561 proposes reducing the deviation of the solar cell element from the light receiving surface side electrode and the tab.

JP 2006-196749 JP 2006-93481 A

  However, in patent document 2, the proposal with respect to the shift | offset | difference of a back surface collection electrode and a tab is not made. When the back surface collecting electrode and the tab are displaced, it causes a decrease in bonding strength due to a decrease in bonding area and a decrease in power generation efficiency due to current collection loss. In addition, in the backside collecting electrode, the area of the backside collecting electrode is reduced to improve the power generation efficiency and reduce the cost by reducing the backside collecting electrode, and the tab is easily protruded from the backside collecting electrode. .

  The present invention has been made in view of the above, and provides a solar cell module manufacturing apparatus that suppresses a deviation from a back surface collecting electrode caused by bending or meandering of a tab and does not cause a decrease in bonding strength or a collecting loss. The purpose is to obtain.

  In order to solve the above-described problems and achieve the object, the present invention provides a plurality of solar cell elements each having a collector electrode on the light receiving surface and a back collector electrode on the back surface, and another collector electrode adjacent to the collector electrode. An apparatus for manufacturing a solar cell module including a string having a plurality of tabs connected to a back surface collecting electrode of the solar cell element, the joining stage on which the solar cell element is placed, and the length of the collecting electrode Tab transfer mechanism for placing a tab from above on the collector electrode of the solar cell element on the junction stage so as to protrude from one end of the direction to the solar cell element, and the back collector electrode of another solar cell element , The solar cell element transfer mechanism for lowering the tab and bending the tab until the tab comes into contact with the joining stage, and the height is variable. The wall provided on the joining stage And a tab correction means for restricting the side portion of the tab protruding from the solar cell element from the side, and the wall portion while the solar cell element transfer mechanism bends the tab. The height between the first height that is equal to or higher than the height of the light receiving surface of the solar cell element on the bonding stage and the second height that is equal to or lower than the height of the upper surface of the tab in contact with the bonding stage. It is characterized by changing.

  ADVANTAGE OF THE INVENTION According to this invention, there exists an effect that the shift | offset | difference with the back surface current collection electrode produced by the curve of a tab or meandering can be suppressed, and generation | occurrence | production of the fall of joining strength and a current collection loss can be prevented.

FIG. 1 is a top view of a solar cell element provided in a solar cell module manufactured by an embodiment of a solar cell module manufacturing apparatus according to the present invention. FIG. 2 is a bottom view of the solar cell element as viewed from the side opposite to the light receiving surface. FIG. 3 is a perspective view showing a schematic configuration of the solar cell module. FIG. 4 is a flowchart showing a manufacturing process of the solar cell module. FIG. 5 is a schematic diagram of a solar cell module manufacturing apparatus that is manufacturing a solar cell module. FIG. 6 is a schematic diagram of a solar cell module manufacturing apparatus that is manufacturing a solar cell module. FIG. 7 is a schematic diagram of a solar cell module manufacturing apparatus that is manufacturing a solar cell module. FIG. 8 is a diagram showing a state in which the solar cell element is arranged on the tab arranged on the bonding stage. FIG. 9 is a diagram showing a solar cell module according to the present invention. FIG. 10 is a cross-sectional view of the solar cell module.

  Embodiments of a solar cell module manufacturing apparatus according to the present invention will be described below in detail with reference to the drawings. Note that the present invention is not limited to the embodiments. In the drawings used in the following description, the scale of each member may be different from the actual scale for easy understanding. The same applies between the drawings. Further, in order to make the drawing easy to see, hatching may be added to the plan view, or hatching may be omitted in the cross-sectional view.

Embodiment.
FIG. 1 is a top view of a solar cell element provided in a solar cell module manufactured by an embodiment of a solar cell module manufacturing apparatus according to the present invention. FIG. 2 is a bottom view of the solar cell element as viewed from the side opposite to the light receiving surface. As shown in FIG. 1, in the solar cell element 1, an impurity diffusion layer (not shown) is formed by phosphorous diffusion on the light receiving surface side of a semiconductor substrate 5, and an antireflection film 4 made of a silicon nitride film is formed. ing. Further, on the light receiving surface 10 a side of the semiconductor substrate 5, a long and narrow fine wire electrode 3 and a current collecting electrode 2 that is electrically connected to the fine wire electrode 3 are provided. The thin wire electrode 3 and the current collecting electrode 2 are electrically connected to the impurity diffusion layer at their bottom portions.

  Further, as shown in FIG. 2, the back surface 7 b of the solar cell element 1 (surface opposite to the light receiving surface 10 a) is provided with the back surface electrode 7 over substantially the whole, and extends in substantially the same direction as the current collecting electrode 2. Thus, the back surface collecting electrode 6 is provided.

  FIG. 3 is a perspective view showing a schematic configuration of the solar cell module. As shown in FIG. 3, a plurality of (for example, 10) conductive tabs 34 are soldered to the back surface collecting electrode 6 of the solar cell element 1 and the collecting electrode 2 of the adjacent solar cell element 1. ) Of solar cell elements 1 are connected in series. The tab 34 is made of copper, and has a surface coated with solder (for example, Sn—Ag—Cu solder) in advance.

  Further, by soldering the tab 34 derived from the string 35 to the output lead frame 36, a plurality of (for example, five) strings 35 are electrically connected. The output lead frame 36 is made of copper, and has a surface coated with solder (for example, Sn—Ag—Cu solder) in advance. A plurality of strings 35 are sealed with glass, a sealing material, and a back surface member (all not shown) to form a solar cell module.

  Next, the manufacturing process of the solar cell module, particularly the manufacturing process of the string 35 will be described in detail. FIG. 4 is a flowchart showing a manufacturing process of the solar cell module. FIG. 5 is a schematic diagram of a solar cell module manufacturing apparatus that is manufacturing a solar cell module. FIG. 5A is a diagram illustrating a step of arranging tabs 34 on the solar cell element 1 and the junction stage 13 on the junction stage. FIG. 5 (b) shows a state where the tab transfer mechanism and the tab correction cage are in contact with each other, and FIG. 5 (c) shows a state where the solar cell element and the tab are in contact with each other. Indicates the state. FIG. 6 is a schematic view of a solar cell module manufacturing apparatus that is manufacturing a solar cell module, and FIG. 6 (a) is a side view of a solar cell element and a joining stage in which tabs are arranged. 6 (b) is a top view. FIG. 7 is a schematic diagram of a solar cell module manufacturing apparatus that is manufacturing a solar cell module. FIG. 7 (a) shows a solar cell element and a solar cell element in a step of arranging the solar cell element on a tab on a joining stage. FIG. 7B shows a state before the tab straightening cage comes into contact, FIG. 7B shows a state where the solar cell element and the tab straightening cage come into contact, and FIG. 7C shows the tab as a joining stage. The state which contacted is shown. The solar cell module manufacturing apparatus according to the embodiment includes a joining stage 13, a tab correction cage 12, a tab transfer mechanism 11, and a solar cell element transfer mechanism 14. The tab correction cage 12 has a wall portion 12a protruding from the joining stage 13 and a drive mechanism (not shown) that changes the height of the wall portion 12a, and the height of the wall portion 12a is variable. . The maximum height (first height) of the wall portion 12a is larger than the sum of the thickness of the solar cell element 1 and the thickness of the tab 34 (more than the height of the light receiving surface of the solar cell element 1). . The minimum height (second height) of the wall portion 12a is equal to or less than the thickness of the tab 34 (less than the height of the upper surface of the tab 34 in contact with the joining stage 13). A drive mechanism (not shown) is provided in the joining stage 13 and raises and lowers the wall 12a (changes the height).

  In manufacturing the string, a plurality of solar cell elements 1 are arranged. Therefore, in the following description, the solar cell element 1 in which the tab 34 is installed on the back surface and the solar cell in which the tab 34 is not installed on the back surface. When it is necessary to distinguish the element 1, the solar cell element 1 having the tab 34 installed on the back surface is distinguished as the solar cell element 1a, and the non-installed solar cell element 1 is distinguished as the solar cell element 1b. When it is necessary to distinguish between the tab 34 installed on the back surface of the solar cell element 1a and the tab 34 installed on the back surface of the solar cell element 1b, the tab installed on the back surface of the solar cell element 1a. 34 is identified as a tab 34a, and the tab 34 installed on the back surface of the solar cell element 1b is distinguished as a tab 34b. Note that these are only distinguished for convenience in describing the manufacturing process of the string, and the solar cell element 1a and the solar cell element 1b are not different types of solar cell elements, but the tab 34a and the tab 34b. Is not different.

  When manufacturing the string 35, first, the solar cell element 1 a having the tab 34 a on the back surface is placed on the joining stage 13, and then the wall portion 12 a housed in the joining stage 13 is raised. The height of the wall portion 12a at this time is larger than the sum of the thickness of the solar cell element 1 and the thickness of the tab 34. Next, as shown in FIG. 5A, the tab 34b cut to a predetermined length is adsorbed by the tab transfer mechanism 11 to restrict the bending, and is moved to the sky above the joining stage 13 (step S1). . When the tab transfer mechanism 11 is lowered and the tab transfer mechanism 11 and the tab correction cage 12 come into contact with each other as shown in FIG. 5B, the tab 34b is separated from the tab transfer mechanism 11, and FIG. As shown in FIG. 4, the tab 34b is disposed on the solar cell element 1a and the bonding stage 13 (step S2). At this time, the tab 34b is disposed so as to protrude out of the solar cell element 1a from one end in the longitudinal direction of the collecting electrode. As shown in FIG. 6B, at this time, the tab 34b is surrounded by the wall portion 12a so that the bend is restricted by the tab correction cage 12 and is kept straight, so there is no fear of meandering. The bending of the tab 34 is only restricted by being surrounded by the wall portion 12a. When the tab 34 is taken out from the tab correction cage 12, it returns to its original state. That is, the work hardening generated in the tab 34b is small compared to the conventional method of correcting the tab with a roller or the like so as to be straight even in an unsupported state.

  Next, as shown to Fig.7 (a), the solar cell element 1b is moved to the sky of the tab 34b by the solar cell element transfer mechanism 14 (step S3). The solar cell element transfer mechanism 14 is lowered, and as shown in FIG. 7B, the solar cell element 1b comes into contact with the tab correction cage 12 and at the same time, the wall 12a is also lowered to move the solar cell element transfer mechanism 14. The wall 12a is sunk into the joining stage 13 at the same speed as the speed, and the tab 34b is pushed and bent as shown in FIG. 7C (step S4).

  In order to lower the wall portion 12a at the same time when the solar cell element 1b comes into contact with the tab straightening cage 12, the contact between the solar cell element 1b and the tab straightening cage 12 is detected by a sensor (not shown), and the detection result of the sensor is displayed. Accordingly, the wall portion 12a may be lowered by a drive mechanism (not shown). Further, assuming that the solar cell element 1b is in contact with the tab correction cage 12 when the solar cell element transfer mechanism 14 is lowered to a predetermined height, the wall portion 12a is lowered at the same speed as the solar cell element transfer mechanism 14. You may make it let it.

  The descent of the solar cell element transfer mechanism 14 is stopped at a position where the tab 34b comes into contact with the bonding stage 13, the suction of the tab 34b is released, and then the solar cell element transfer mechanism 14 is retracted from the bonding stage 13. FIG. 8 is a diagram showing a state in which the solar cell element is arranged on the tab arranged on the joining stage, FIG. 8 (a) is a side view, and FIG. 8 (b) is a diagram in FIG. 8 (a). It is sectional drawing along the VIIIb-VIIIb line. By retracting the solar cell element transfer mechanism 14 from the bonding stage 13, as shown in FIGS. 8A and 8B, the solar cell element 1b is disposed on the tab 34b (step S5).

  Even after the descent of the solar cell element transfer mechanism 14 is stopped, the descent of the wall portion 12a is continued until the minimum height is reached. At this time, the tab 34b is held straight between the solar cell element 1b and the joining stage 13 so as to be straight as in the shape of the space inside the tab correction cage 12 (the portion surrounded by the wall portion 12a). .

  After the steps S1 to S5 in FIG. 4 are completed, the tabs 34a and 34b and the solar cell element 1a are joined. The joining between the tabs 34a and 34b and the solar cell element 1a was performed by melting the solder supplied in advance to the tabs 34a and 34b by heating with an infrared lamp heater or the like, and then stopping the heating and melting. By solidifying the solder, the collector electrode 2 and the tab 34a, and the back collector electrode 6 and the tab 34b are soldered, respectively. By repeating the above steps, the string 35 shown in FIG. 3 is formed.

  The tabs 34a, 34b and the solar cell element 1a may be joined together after the solar cell elements 1 for one string 35 have been arranged. In this case, a pressing mechanism (not shown) is provided in the solar cell module manufacturing apparatus, and before the tab 34b is pushed and bent, the tab 34b is pressed onto the solar cell element 1a by the pressing mechanism. What is necessary is just to make it not float from 1a.

  The process of manufacturing the solar cell module includes a process of manufacturing the solar cell element 1 before and after the flowchart shown in FIG. 4 and a process of sealing the string 35 with glass or a sealing material. May be performed by the following general steps.

  FIG. 9 is a diagram showing a solar cell module according to the present invention. FIG. 10 is a cross-sectional view of the solar cell module, showing a cross section taken along line XX in FIG. The solar cell module includes a solar cell element 1, a back sheet 52, a tab 34, an output lead frame 36, a positive extraction electrode 55, a negative extraction electrode 56, a reinforced cover glass 57, and a solar cell sealing material 58.

  The back sheet 52 is formed using a material having moisture resistance (for example, polyvinyl fluoride (PVF)) as a raw material, and is disposed on the back side of the solar cell element 1. The tab 34 and the output lead frame 36 interconnect the solar cell elements 1. The reinforced cover glass 57 is disposed on the front side of the solar cell element 1. The solar cell sealing material 58 is formed using, for example, ethylene vinyl acetate (EVA) as a raw material, and is disposed between the back sheet 52 and the reinforced cover glass 57 so as to protect the solar cell element 1. .

  Since the solar cell element 1 is configured with a negative electrode on the light-receiving surface side and a positive electrode on the back surface side, in FIG. 9, the upper and lower sides of the solar cell elements 1 adjacent in the horizontal direction are interconnected by tabs 34 mainly composed of copper. To do. Similarly, the string 35 connected in the horizontal direction is also electrically connected by the output lead frame 36, and finally, the electricity can be extracted by the plus extraction electrode 55 and the minus extraction electrode 56.

  In addition, since the solar cell module is required to have long-term reliability, as shown in FIGS. 9 and 10, the string 35 prevents intrusion of rain and the like while transmitting sunlight, and absorbs impacts such as falling objects. The outermost surface is covered with a reinforced cover glass having a function to perform.

  Further, a back sheet 52 having excellent water resistance and the like is provided on the back side of the string 35. A gap between the solar cell element 1 and the reinforced cover glass 57 and a gap between the solar cell element 1 and the back sheet 52 are filled with a solar cell sealing material 58, and moisture resistance is improved. The solar cell sealing material 58 is generally made of a thermosetting resin (such as EVA) having a high light transmittance. When EVA is applied to the solar cell sealing material 58, workability is good when a sheet-like material is used.

  Here, the manufacturing process of the solar cell panel in the present embodiment will be described. A tab 34 is connected to the solar cell element 1 to create a string 35. Next, the output lead frame 36, the positive extraction electrode 55, and the negative extraction electrode 56 are connected to the string 35. When the string 35 is sandwiched between two EVA sheets and further sandwiched between the reinforced cover glass 57 and the back sheet 52 and heated simultaneously with defoaming, a solar cell panel having a structure with no gap as shown in FIG. 10 is obtained. can get.

  As described above, in the present embodiment, when the tab 34 is arranged at a desired position, the wall portion 12a built in the joining stage 13 rises, so that the tab 34 meanders or curves. However, when the solar cell element 1 is arranged on the tab 34, the wall portion 12a is lowered, so that the tab 34 and the sun are corrected while straightening the tab 34. The battery element 1 can be joined.

  Therefore, the deviation between the tab 34 and the back surface collecting electrode 6 can be suppressed. Thereby, current collection loss can be suppressed and power generation efficiency can be improved. Moreover, since it is not necessary to correct the tab 34 until it becomes straight in an unsupported state, an increase in the yield strength of the tab 34 due to work hardening can be suppressed, and when the solar cell element 1 and the tab 34 are soldered Stress can be reduced, and damage to the solar cell element 1 can be prevented.

  Further, since it is not necessary to use an adsorption system in order to maintain the tab in a state in which bending is suppressed, there is no possibility of the tab meandering due to clogging of the adsorption system, and the yield can be improved. Moreover, since the cleaning operation required when the adsorption system is clogged is unnecessary, the productivity of the solar cell module can be improved.

  As described above, the solar cell module manufacturing apparatus according to the present invention is useful in that it can prevent the back surface collecting electrode and the tab from being displaced on the back side of the module.

  1, 1a, 1b Solar cell element, 2 collector electrode, 3 wire electrode, 4 antireflection film, 5 semiconductor substrate, 6 back collector electrode, 10a light receiving surface, 10b back surface, 11 tab transfer mechanism, 12 tab correction cage , 12a wall part, 13 joining stage, 14 solar cell element transfer mechanism, 34, 34a, 34b tab, 35 string, 36 output lead frame, 52 back sheet, 55 plus take-out electrode, 56 minus take-out electrode, 57 reinforced cover glass 58 Solar cell sealant.

Claims (2)

A plurality of solar cell elements each having a current collecting electrode on the light receiving surface and a back surface collecting electrode on the back surface, and a plurality of tabs for connecting the current collecting electrode to the back surface collecting electrode of another solar cell element adjacent thereto An apparatus for manufacturing a solar cell module including a string having:
A joining stage on which the solar cell element is placed;
A tab transfer mechanism for mounting a tab from above on the current collecting electrode of the solar cell element on the joining stage so as to protrude out of the solar cell element from one end in the longitudinal direction of the current collecting electrode;
After the back surface collecting electrode of another solar cell element is brought into contact with the portion of the tab protruding outside the solar cell element from above, the tab is lowered until the tab contacts the joining stage. A solar cell element transfer mechanism for bending
And a tab correction means that has a wall portion provided on the joining stage with a variable height, and that the wall portion regulates from the side that the protruding portion of the tab protrudes outside the solar cell element. ,
While the solar cell element transfer mechanism bends the tab, the wall portion contacts the junction stage with a first height that is equal to or higher than the height of the light receiving surface of the solar cell element on the junction stage. An apparatus for manufacturing a solar cell module, wherein the height is changed between a second height which is a height equal to or less than a height of an upper surface of the tab.   The tab correction means is configured to sink the wall portion into the joining stage at the same speed as the moving speed of the solar cell element transfer mechanism while the solar cell element transfer mechanism bends the tab. The solar cell module manufacturing apparatus according to claim 1.