TWI528572B - Solar cell structure, method for manufacturing the same and solar cell module - Google Patents

Description

Solar cell structure, manufacturing method thereof and solar cell module

The present invention relates to a photoelectric conversion device, and more particularly to a solar cell structure and a method of fabricating the same.

After the solar cell module is completed, it is usually required to carry out reliability tests to ensure that the solar cell modules produced can pass the international certification and customer requirements. In general, the reliability test of solar cell modules mainly includes visual inspection, insulation test, low illumination performance test, outdoor exposure test, hot spot endurance test, ultraviolet test, thermal cycling test, and wet. Humidity freeze test, damp heat test, lead end test, wet leakage current test, mechanical load test, hail test and light decay test, and the like.

However, after the thermal cycle test, the solar cell module often suffers from a decrease in the fill factor, which in turn causes a decrease in the maximum output power. Please refer to FIG. 1 , which is a top view of a conventional solar cell. After analyzing the solar cell 100 in the solar cell module after the thermal cycle test, it is found that the front side of the solar cell 100 is 102. The finger electrode 106 of the upper portion is damaged. The breakage of the finger electrode 106 occurs at a position corresponding to the position of the electrode portion 110 of the bus electrode 108 on the back surface of the solar cell 100. Due to the breakage of the finger electrodes 106, the finger electrodes 106 cannot be effectively connected to the bus electrodes 104, so that the current collected by the finger electrodes 106 cannot be smoothly transmitted and collected to the bus electrodes 104, thereby causing the output power of the solar cells 100. decline.

Therefore, an aspect of the present invention provides a solar cell structure, a method of fabricating the same, and a solar cell module, wherein a surface of one of the substrates is provided with a plurality of auxiliary electrodes that intersect the finger electrodes but do not intersect the bus electrodes. The auxiliary electrode corresponds to the electrode portion of the bus electrode on the other surface of the substrate. When the finger electrodes are broken and the current cannot be directly conducted to the bus electrodes, the current of the finger electrodes can be smoothly collected to the bus electrodes through the conduction of the auxiliary electrodes. Therefore, the loss of the fill factor can be reduced, thereby improving the energy conversion efficiency of the solar cell.

Another aspect of the present invention provides a solar cell structure, a method of fabricating the same, and a solar cell module including a plurality of auxiliary wires that can be connected to the bus electrode and the auxiliary electrode, thereby providing further protection for assisting When the electrode cannot smoothly transfer the current from the finger electrode to the bus electrode, the current is smoothly collected to the bus electrode. Further, the auxiliary wire is wider than the finger electrode, and the joint stability between the finger electrode and the bus electrode corresponding to the electrode portion can be improved, and the joint fracture between the finger electrode and the bus electrode can be avoided.

According to the above object of the present invention, a solar cell junction is proposed Structure. The solar cell structure includes a substrate, a first electrode, and a second electrode. The substrate has opposing first and second surfaces. The first electrode is disposed on the first surface, and includes at least one first bus electrode, a plurality of finger electrodes, and a plurality of first auxiliary electrodes, wherein the finger electrodes intersect the first bus electrode, the first auxiliary electrode and the first The bus electrodes do not intersect. The second electrode is disposed on the second surface and includes at least one second bus electrode. The second bus electrode includes a plurality of electrode portions corresponding to the first auxiliary electrode, wherein the electrode portions are arranged along the extending direction of the first bus electrode, and the orthographic projection of each electrode portion with respect to the first surface overlaps with the first bus electrode In addition, the orthographic projections do not form a plurality of intervals in the extending direction. The finger electrode includes a plurality of first finger electrodes, and the first finger electrodes intersect the orthographic projection of the electrode portions, and each of the first auxiliary electrodes is located beside one of the orthographic projections of the corresponding electrode portions, and The first finger electrodes intersecting the corresponding orthographic projections intersect.

According to an embodiment of the present invention, the finger electrode further includes a plurality of second finger electrodes located in the interval, and one end of each of the first auxiliary electrodes protrudes from an interval adjacent to one end of the corresponding orthographic projection, and The second finger electrodes adjacent to the corresponding orthographic projections intersect in the protruding interval.

According to another embodiment of the present invention, the other end of each of the first auxiliary electrodes protrudes from the interval adjacent to the other end of the corresponding orthographic projection, and is adjacent to the second of the corresponding orthographic projections in the interval between the protrusions The finger electrodes intersect.

According to still another embodiment of the present invention, the first electrode further includes a plurality of first auxiliary wires corresponding to the first auxiliary electrodes, and each of the first auxiliary wires is connected to the corresponding first auxiliary electrode and the first bus electrode.

According to still another embodiment of the present invention, each of the first auxiliary wires has a width greater than a width of each of the finger electrodes.

According to still another embodiment of the present invention, the first electrode further includes a plurality of second auxiliary electrodes, wherein the second auxiliary electrodes do not intersect with the first bus electrodes, and correspond to the first auxiliary electrodes, and each of the second auxiliary electrodes And the corresponding first auxiliary electrodes are respectively located on opposite sides of the orthographic projection of the corresponding electrode portions.

According to still another embodiment of the present invention, the first electrode further includes a plurality of second auxiliary wires corresponding to the second auxiliary electrodes, and each of the second auxiliary wires is connected to the corresponding second auxiliary electrode and the first bus electrode.

According to still another embodiment of the present invention, each of the second auxiliary electrodes and the corresponding first auxiliary electrode are respectively located outside the opposite edges of the orthographic projection of the corresponding electrode portion along the extending direction.

According to the above object of the present invention, a solar battery module is further proposed. The solar cell module comprises an upper plate, a lower plate, a solar cell structure as described above, a plurality of connecting strips, and at least one layer of encapsulating material. The solar cell structure is disposed between the upper plate and the lower plate. The connection is electrically connected to an adjacent solar cell structure. A layer of encapsulating material is positioned between the upper and lower plates to bond the solar cell structure to the upper and lower plates.

According to the above object of the present invention, a method of manufacturing a solar cell structure is also provided, comprising the following steps. A substrate is provided, the substrate having opposing first and second surfaces. Forming a first electrode on the first surface, wherein the first electrode comprises at least one first bus electrode, a plurality of finger electrodes, and a plurality of first auxiliary electrodes, the finger electrodes and the first confluence The electrodes intersect and the first auxiliary electrode does not intersect the first bus electrode. Forming a second electrode on the second surface, wherein the second electrode comprises at least one second bus electrode, and the second bus electrode comprises a plurality of electrode portions corresponding to the first auxiliary electrode. The electrode portions are arranged at intervals along the extending direction of the first bus electrode, and the orthographic projection of each electrode portion with respect to the first surface overlaps with the first bus electrode, and further, the orthographic projections are formed in a plurality of intervals in the extending direction. The finger electrode includes a plurality of first finger electrodes, and the first finger electrodes intersect the orthographic projection of the electrode portions, and each of the first auxiliary electrodes is located beside one of the orthographic projections of the corresponding electrode portions, and corresponds to The first finger electrodes intersecting the orthographic projections intersect.

According to an embodiment of the invention, the step of forming the first electrode further comprises: the finger electrode comprises a plurality of second finger electrodes, wherein the second finger electrodes are located in the interval between the electrode portions, and each of the first auxiliary electrodes One of the ends protrudes into a space adjacent one end of the corresponding orthographic projection and intersects the second finger electrode adjacent to the corresponding orthographic projection in the projected interval.

According to another embodiment of the present invention, the other end of each of the first auxiliary electrodes protrudes from the interval adjacent to the other end of the corresponding orthographic projection, and is adjacent to the second of the corresponding orthographic projections in the interval between the protrusions The finger electrodes intersect.

According to still another embodiment of the present invention, the step of forming the first electrode further includes: the first electrode includes a plurality of first auxiliary wires corresponding to the first auxiliary electrode, and each of the first auxiliary wires is connected to the corresponding first auxiliary electrode With the first bus electrode.

According to still another embodiment of the present invention, each of the first auxiliary wires The width is greater than the width of each finger electrode.

According to still another embodiment of the present invention, the step of forming the first electrode further includes: the first electrode includes a plurality of second auxiliary electrodes, the second auxiliary electrodes do not intersect with the first bus electrode, and the first auxiliary electrode Correspondingly, each of the second auxiliary electrodes and the corresponding first auxiliary electrode are respectively located on opposite sides of the orthographic projection of the corresponding electrode portion.

According to still another embodiment of the present invention, the step of forming the first electrode further comprises: the first electrode includes a plurality of second auxiliary wires corresponding to the second auxiliary electrode, and each of the second auxiliary wires is connected to the corresponding second auxiliary electrode With the first bus electrode.

According to still another embodiment of the present invention, each of the second auxiliary electrodes and the corresponding first auxiliary electrode are respectively located outside the opposite edges of the orthographic projection of the corresponding electrode portion along the extending direction.

100‧‧‧ solar cells

102‧‧‧ positive

104‧‧‧Concurrent electrode

106‧‧‧ finger electrode

108‧‧‧Concurrent electrode

110‧‧‧Electrode

200‧‧‧Solar battery module

202a‧‧‧Solar cell structure

202b‧‧‧Solar cell structure

204‧‧‧Substrate

206‧‧‧ first surface

208‧‧‧ second surface

210a‧‧‧first electrode

210b‧‧‧first electrode

212‧‧‧First bus electrode

214‧‧‧second electrode

216‧‧‧Second bus electrode

218‧‧‧Upper board

220‧‧‧ Lower board

222‧‧‧Package material layer

224a‧‧‧first finger electrode

224b‧‧‧second finger electrode

226a‧‧‧First auxiliary electrode

226b‧‧‧second auxiliary electrode

228a‧‧‧First auxiliary conductor

228b‧‧‧Second auxiliary conductor

230‧‧‧Connecting belt

232‧‧‧Electrode

234‧‧‧ interval

236‧‧‧ Extension direction

238‧‧‧

240‧‧‧

242‧‧‧

244‧‧‧

246‧‧‧ length

248‧‧‧ length

250‧‧‧ length

252‧‧‧Width

254‧‧‧Width

256‧‧‧Width

258‧‧‧Width

300‧‧‧Steps

302‧‧‧Steps

304‧‧‧Steps

The above and other objects, features, advantages and embodiments of the present invention will become more <RTIgt; <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt;

2 is a cross-sectional view showing a solar cell module in accordance with an embodiment of the present invention.

3 is a top plan view showing a solar cell structure in accordance with an embodiment of the present invention.

4 is a diagram showing a solar energy according to an embodiment of the present invention. A partially enlarged schematic view of the battery structure.

Figure 5 is a top plan view showing a solar cell structure in accordance with another embodiment of the present invention.

Figure 6 is a partially enlarged top plan view showing the structure of a solar cell according to another embodiment of the present invention.

Figure 7 is a flow chart showing the fabrication of a solar cell structure in accordance with an embodiment of the present invention.

Please refer to FIG. 2, which is a cross-sectional view showing a solar cell module according to an embodiment of the present invention. In the present embodiment, the solar cell module 200 mainly includes an upper plate 218, a lower plate 220, a plurality of solar cell structures 202a, a plurality of connecting strips 230, and one or more encapsulating material layers 222.

In some embodiments, the upper plate 218 is a transparent sheet material, such as glass. The lower plate 220 may also be referred to as a back sheet, and the lower plate 220 may be a white opaque sheet. The solar cell structure 202a is disposed between the upper plate 218 and the lower plate 220. The connecting strip 230 is also located between the upper boards 218 and 220, and the two ends of each connecting strip 230 are respectively connected to the adjacent two solar cell structures 202a to electrically connect the two solar cell structures 202a. The strap 230 can also be referred to as a solder ribbon. The encapsulation material layer 222 is also located between the upper plate 218 and the lower plate 220. These solar cell structures 202a and tie strips 230 can be joined to the lower plate 220 and the upper plate 218 by the high temperature lamination process when the encapsulating material layer 222 is in the molten state. In an exemplary embodiment, encapsulating material layer 222 is an ethylene vinyl acetate copolymer (EVA).

Please refer to FIG. 2 to FIG. 4 simultaneously, wherein FIG. 3 and FIG. 4 are respectively a top view and a partially enlarged top view of a solar cell structure according to an embodiment of the present invention. In some embodiments, solar cell structure 202a primarily includes substrate 204, first electrode 210a, and second electrode 214. As shown in FIG. 2, the substrate 204 has a first surface 206 and a second surface 208, wherein the first surface 206 and the second surface 208 are respectively located on opposite sides of the substrate 204. The material of the substrate 204 can be a semiconductor material such as germanium. The substrate 204 has a corresponding doped region (not shown) according to the positions of the first electrode 210a and the second electrode 214. In an exemplary embodiment, first surface 206 is the front side of substrate 204 and second surface 208 is the back side of substrate 204.

As shown in FIG. 3, the first electrode 210a is disposed on the first surface 206 of the substrate 204. The material of the first electrode 210a may be a metal paste such as a silver paste. In some embodiments, the first electrode 210a includes one or more first bus electrodes 212, a plurality of auxiliary electrodes, and a plurality of finger electrodes. In an exemplary example, as shown in FIG. 3, the first electrode 210a includes three first bus electrodes 212. The finger electrode includes a plurality of first finger electrodes 224a and a plurality of second finger electrodes 224b. The first finger electrodes 224a and the second finger electrodes 224b are substantially equal in width. The first finger electrode 224a intersects the second finger electrode 224b and the first bus electrode 212, that is, the first finger electrode 224a and the second finger electrode 224b are directly bonded to at least the first bus electrode 212. In some exemplary examples, each of the first finger electrodes 224a is orthogonal to the second finger electrodes 224b and the first bus electrodes 212. In addition, as shown in FIG. 4, the width 254 of each of the first finger electrodes 224a and the second finger electrodes 224b is small. The width 256 of the first bus electrode 212 is 256. The current of the first finger electrode 224a and the second finger electrode 224b may be collected to the first bus electrode 212.

In some embodiments, the auxiliary electrode includes only a plurality of first auxiliary electrodes 226a, and each of the first bus electrodes 212 is disposed adjacent to the plurality of first auxiliary electrodes 226a. In such an embodiment, the first auxiliary electrodes 226a may be located on the same side of the corresponding first bus electrodes 212; however, the first auxiliary electrodes 226a may also be non-uniformly disposed on the same side of the corresponding first bus electrodes 212, and It is disposed on opposite sides of the corresponding first bus electrode 212. For example, in the embodiment where the first electrode 210a includes only the first auxiliary electrode 226a and the first electrode 210a is formed by screen printing, the first auxiliary electrode 226a may be disposed on the network of the corresponding first bus electrode 212. The printing process enters the knife side. In addition, the first auxiliary electrodes 226a are not intersected with the corresponding first bus electrodes 212. In some examples, the first auxiliary electrode 226a extends along the extending direction 236 of the corresponding first bus electrode 212. In some exemplary examples, the first auxiliary electrode 226a is parallel to the corresponding first bus electrode 212. In other exemplary examples, the first auxiliary electrode 226 is not parallel to the corresponding first bus electrode 212.

In other embodiments, as shown in FIG. 3, the auxiliary electrode includes a plurality of first auxiliary electrodes 226a and a plurality of second auxiliary electrodes 226b, and each of the first bus electrodes 212 is disposed corresponding to the plurality of first auxiliary devices. The electrode 226a and the plurality of second auxiliary electrodes 226b. In such an embodiment, the first auxiliary electrodes 226a correspond to the second auxiliary electrodes 226b, respectively. The first auxiliary electrode 226a and the second auxiliary electrode 226b corresponding to each other are adjacent to opposite sides of the corresponding first bus electrode 212, respectively. In addition, the first auxiliary electrode 226a Both the second auxiliary electrode 226b and the corresponding first bus electrode 212 do not intersect. In some examples, the first auxiliary electrode 226a and the second auxiliary electrode 226b both extend along the extending direction 236 of the first bus electrode 212. In some exemplary examples, the first auxiliary electrode 226a and the second auxiliary electrode 226b are both parallel to the corresponding first bus electrode 212. In other exemplary examples, the first auxiliary electrode 226a and the second auxiliary electrode 226b and the corresponding first bus electrode 212 are not parallel. The following description of the embodiment is performed with an embodiment in which the first electrode 210a includes the first auxiliary electrode 226a and the second auxiliary electrode 226b.

As shown in FIG. 2, the second electrode 214 is disposed on the second surface 208 of the substrate 204, and is located on opposite sides of the substrate 204 from the first electrode 214. The material of the second electrode 214 may be a metal paste such as a silver paste. The second electrode 214 includes one or more second bus electrodes 216. In some embodiments, as shown in FIG. 3, the number and position of the second bus electrodes 216 correspond to the first bus electrode 212. Each of the second bus electrodes 216 includes a plurality of electrode portions 232. Therefore, the orthographic projection of each electrode portion 232 on the first surface 206 overlaps with the corresponding first bus electrode 212. In each of the second bus electrodes 216, the electrode portions 232 are spaced apart along the extending direction 236 of the first bus electrode 212, that is, each of the second bus electrodes 216 is discontinuous. The orthographic projection of the non-electrode portion 232 is such that the spacer 234 is formed in the extending direction 236 of the first bus electrode 212.

Further, among all the finger electrodes of the first electrode 210a, the front projections of the first finger electrodes 224a and the electrode portions 232 of the second bus electrodes 216 on the first surface 206 intersect. On the other hand, the second finger electrode 224b is Pass through the above interval 234. Referring to FIGS. 3 and 4 simultaneously, the first auxiliary electrode 226a and the second auxiliary electrode 226b of the first electrode 210a correspond to the electrode portions 232 of the second bus electrode 216, respectively. That is, each of the electrode portions 232 corresponds to a first auxiliary electrode 226a and a second auxiliary electrode 226b, and the first auxiliary electrode 226a and the second auxiliary electrode 226b are respectively located at the first surface 206 of the corresponding electrode portion 232. The opposite sides of the projection. In an exemplary embodiment, the first auxiliary electrode 226a and the second auxiliary electrode 226b are respectively located on the outer sides of the opposite edges of the corresponding electrode portion 232 along the extending direction 236 of the orthographic projection of the first surface 206, that is, the first auxiliary electrode. The distance from the second auxiliary electrode 226b to the corresponding first bus electrode 212 is greater than the two edges of the positive projection of the electrode portion 232 at the first surface 206 along the extending direction 236 to the corresponding first bus electrode 212, respectively. distance.

Referring to FIG. 2 and FIG. 4 again, in some exemplary examples, the first auxiliary electrode 226a and the second auxiliary electrode 226b are respectively located outside the two edges of the connecting strip 230 that is attached to the first bus electrode 212, that is, the first The distance from the auxiliary electrode 226a and the second auxiliary electrode 226b to the corresponding first bus electrode 212 is greater than the distance from the two edges of the connecting strip 230 that is bonded to the first bus electrode 212 to the first bus electrode 212, respectively.

As shown in FIG. 4, for each of the electrode portions 232, the first auxiliary electrode 226a and the second auxiliary electrode 226b, which are disposed on opposite sides of the orthographic projection thereof, respectively have a first finger shape intersecting the orthographic projection. Electrodes 224a intersect. In some embodiments, for the orthographic projection of each electrode portion 232 on the first surface 206, corresponding to the first auxiliary electrode disposed adjacent to the orthographic projection One end 238 of 226a protrudes into a space 234 adjacent one end of the orthographic projection and intersects the second finger electrode 224b adjacent to the orthographic projection in the projected interval 234. In other embodiments, for the orthographic projection of each electrode portion 232 on the first surface 206, the other end 240 of the first auxiliary electrode 226a disposed adjacent to the orthographic projection protrudes adjacent to the orthographic projection. The other end of the space 234 intersects the second finger electrode 224b adjacent to the orthographic projection in the projected interval 234. That is, the length 246 of the first auxiliary electrode 226a is longer than the length 248 of the corresponding electrode portion 232, as shown in FIG.

Similarly, in some embodiments, for the orthographic projection of each electrode portion 232 on the first surface 206, an end 242 corresponding to the second auxiliary electrode 226b disposed adjacent to the orthographic projection protrudes adjacent to the orthographic projection In one of the spaces 234, and intersecting the second finger electrode 224b adjacent to the orthographic projection in the protruding interval 234. In other embodiments, for the orthographic projection of each electrode portion 232 on the first surface 206, the other end 244 of the second auxiliary electrode 226b disposed adjacent to the orthographic projection protrudes adjacent to the orthographic projection. The other end of the space 234 intersects the second finger electrode 224b adjacent to the orthographic projection in the projected interval 234. That is, the length 250 of the second auxiliary electrode 226b is longer than the length 248 of the corresponding electrode portion 232, as shown in FIG.

In the solar cell structure 202a, when the first finger electrode 224a of the first electrode 210a is broken due to the influence of thermal stress, and thus cannot be in effective communication with the first bus electrode 212, the electrode portion 232 of the second bus electrode 216 is disposed. The first auxiliary electrode 226a and the second auxiliary electrode on both sides of the front projection 226b can smoothly conduct current of the first finger electrode 224a to the first bus electrode 212. Therefore, the drop in the fill factor can be effectively avoided, and the output power of the solar cell structure 202a can be improved.

Please refer to FIG. 5 and FIG. 6 simultaneously, which are respectively a top view and a partially enlarged top view of a solar cell structure according to another embodiment of the present invention. The structure of the solar cell structure 202b of the present embodiment is substantially the same as that of the solar cell structure 202a of the above embodiment, and the difference is that the first electrode 210b further includes a plurality of auxiliary wires.

In the embodiment in which the first electrode 210b includes only the first auxiliary electrode 226a, the first electrode 210b further includes a plurality of first auxiliary wires 228a. The first auxiliary wires 228a respectively correspond to the first auxiliary electrodes 226a, and each of the first auxiliary wires 228a is connected to the corresponding first auxiliary electrode 226a and the first bus electrode 212. In some exemplary examples, as shown in FIG. 6, the width 252 of the first auxiliary conductor 228a is greater than the width 254 of each of the first finger electrode 224a and the second finger electrode 224b, such that the first auxiliary conductor 228a and the first The bonding between the bus electrodes 212 is more stable and reliable, and the structural strength of the corresponding regions of the first electrode 210b and the second bus electrode 216 can be improved, and the joint fracture between the first finger electrode 224a and the first bus electrode 212 can be reduced. Probability.

In the embodiment in which the first electrode 210b includes the first auxiliary electrode 226a and the second auxiliary electrode 226b at the same time, as shown in FIG. 5, the first electrode 210b further includes a plurality of second auxiliary wires 228b. The second auxiliary wires 228b correspond to the second auxiliary electrodes 226b, respectively, and each of the second auxiliary wires 228b The corresponding second auxiliary electrode 226b and the first bus electrode 212 are connected. In some exemplary examples, as shown in FIG. 6, the width 258 of the second auxiliary conductor 228b is also greater than the width 254 of each of the first finger electrode 224a and the second finger electrode 224b to lift the second auxiliary conductor 228b. The robustness of the bonding with the first bus electrode 212 can increase the structural strength of the corresponding region of the first electrode 210b and the second bus electrode 216, and reduce the bonding between the first finger electrode 224a and the first bus electrode 212. The probability of breaking.

Please refer to FIG. 2 to FIG. 4 and FIG. 7 together. FIG. 7 is a flow chart showing the fabrication of a solar cell structure according to an embodiment of the present invention. In the present embodiment, when a solar cell is produced, for example, in the solar cell structure 202a of the above embodiment, the substrate 204 may be provided first as described in step 300, as shown in FIG. The substrate 204 has opposing first and second surfaces 206, 208. In addition, the substrate 204 has a corresponding doped region (not shown) according to the positions of the first electrode 210a and the second electrode 214.

Next, the first electrode 210a may be formed on the first surface 206 of the substrate 204 as described in step 302. In some embodiments, the first electrode 210a includes one or more first bus electrodes 212, a plurality of auxiliary electrodes, and a plurality of finger electrodes. For example, one or more screen printing processes can be utilized when forming the first electrode 210a, and various printing sequences are employed. For example, the finger electrode may be printed first, then the first bus electrode 212 may be printed, and then the auxiliary electrode may be printed according to the process requirements; or the first bus electrode 212 may be printed first, then the finger electrode may be printed, and then the auxiliary electrode may be printed; or Printing the finger electrode first, then printing the auxiliary electrode, and then printing the first bus electrode 212; or printing on the same screen The first bus electrode 212, the finger electrode and the auxiliary electrode are simultaneously printed.

The finger electrode includes a plurality of first finger electrodes 224a and a plurality of second finger electrodes 224b. The first finger electrode 224a intersects the second finger electrode 224b and the first bus electrode 212. In some embodiments, the auxiliary electrode may include only a plurality of first auxiliary electrodes 226a, and each of the first bus electrodes 212 is disposed adjacent to the plurality of first auxiliary electrodes 226a. The first auxiliary electrodes 226a are each not intersected with the corresponding first bus electrodes 212. In some exemplary examples, the first auxiliary electrodes 226a may be disposed on the screen printing side of the corresponding first bus electrode 212. In addition, the first auxiliary electrode 226a may extend along the extending direction 236 of the corresponding first bus electrode 212.

In other embodiments, as shown in FIG. 3, the auxiliary electrode includes a plurality of first auxiliary electrodes 226a and a plurality of second auxiliary electrodes 226b, and each of the first bus electrodes 212 is disposed corresponding to the plurality of first auxiliary devices. The electrode 226a and the plurality of second auxiliary electrodes 226b. The first auxiliary electrode 226a and the second auxiliary electrode 226b correspond to each other and are respectively disposed on opposite sides of the first bus electrode 212. The first auxiliary electrode 226a and the second auxiliary electrode 226b both do not intersect with the corresponding first bus electrode 212, and may extend along the extending direction 236 of the first bus electrode 212.

Next, a second electrode 214 can be formed on the second surface 208 of the substrate 204 as described in step 304, as shown in FIG. In some embodiments, the second electrode 214 includes one or more second bus electrodes 216. For example, a screen printing process can be utilized when forming the second electrode 214. As shown in FIG. 3, the number and position of the second bus electrodes 216 correspond to the first bus electrode 212. Further, each of the second bus electrodes 216 includes a plurality of electrode portions 232. because Thus, the orthographic projection of each electrode portion 232 to the first surface 206 overlaps with the corresponding first bus electrode 212. The electrode portions 232 of each of the second bus electrodes 216 are spaced apart along the extending direction 236 of the first bus electrode 212 such that the orthographic projection of the non-electrode portion 232 has an interval 234 in the extending direction 236 of the first bus electrode 212.

In another embodiment, when the first electrode 210a and the second electrode 214 are formed, the second electrode 214 may be formed on the second surface 208 of the substrate 204 to form the first electrode 210a on the first surface of the substrate 204. 206.

In the step of forming the first electrode 210a and the second electrode 214, the electrode portion 232 including the first finger electrode 224a of the first electrode 210a and the second bus electrode 216 of the second electrode 214 is disposed on the first surface 206. The orthographic projections intersect and cause the second finger electrodes 224b to lie in the interval 234 described above. In addition, as shown in FIG. 3 and FIG. 4, each electrode portion 232 corresponds to a first auxiliary electrode 226a and a second auxiliary electrode 226b, and the first auxiliary electrode 226a and the second auxiliary electrode 226b are respectively located at the corresponding electrodes. The portion 232 is adjacent to opposite sides of the orthographic projection of the first surface 206, and the first auxiliary electrode 226a and the second auxiliary electrode 226b each intersect the first finger electrode 224a that intersects the orthographic projection.

In some embodiments, when the first electrode 210a is formed, the one end 238 of the first auxiliary electrode 226a and the one end 242 of the second auxiliary electrode 226b disposed adjacent to the orthographic projection of each electrode portion 232 are protruded adjacent to each other. The interval 234 at one end of the projection intersects with the second finger electrode 224b adjacent to the orthographic projection in this interval 234. In other embodiments, making the first In the case of the electrode 210a, the other end 240 of the first auxiliary electrode 226a and the other end 244 of the second auxiliary electrode 226b, which are disposed adjacent to the orthographic projection of each electrode portion 232, are further protruded from the other end adjacent to the orthographic projection. 234, and the second finger electrodes 224b adjacent to the orthographic projection in the interval 234 intersect. That is, as shown in FIG. 4, the length 246 of the first auxiliary electrode 226a and the length 250 of the second auxiliary electrode 226b are both longer than the length 248 of the corresponding electrode portion 232.

In some embodiments, when the first electrode 210b of the solar cell structure 202a as shown in FIGS. 5 and 6 is formed, the first electrode 210b is further caused to include a plurality of first auxiliary wires 228a and second auxiliary wires 228b. The first auxiliary wires 228a correspond to the first auxiliary electrodes 226a, respectively, and the second auxiliary wires 228b correspond to the second auxiliary electrodes 226b, respectively. The first auxiliary wire 228a is connected to the corresponding first auxiliary electrode 226a and the first bus electrode 212, respectively, and the second auxiliary wire 228b is connected to the corresponding second auxiliary electrode 226b and the first bus electrode 212, respectively. Furthermore, as shown in FIG. 6, the width 252 of the first auxiliary conductor 228a and the width 258 of the second auxiliary conductor 228b are both greater than the width 254 of each of the first finger electrode 224a and the second finger electrode 224b.

According to the above embodiments, an advantage of the present invention is that a surface of the substrate of the solar cell structure is provided with a plurality of auxiliary electrodes that intersect the finger electrodes but do not intersect the bus electrodes, and the auxiliary electrodes are on the other surface of the substrate. The electrode portion of the bus electrode corresponds to each other. When the finger electrodes are broken and the current cannot be directly conducted to the bus electrodes, the current of the finger electrodes can be smoothly collected to the bus electrodes through the conduction of the auxiliary electrodes. Therefore, it can be reduced The loss of the fill factor, which in turn increases the energy conversion efficiency of the solar cell.

According to the above embodiments, another advantage of the present invention is that the solar cell structure and the solar cell module include a plurality of auxiliary wires that can be connected to the bus electrode and the auxiliary electrode, thereby providing further protection so that the auxiliary electrode cannot be smoothly performed. When the current from the finger electrode is transmitted to the bus electrode, the current is smoothly collected to the bus electrode. Further, the auxiliary wire is wider than the finger electrode, and the joint stability between the finger electrode and the bus electrode corresponding to the electrode portion can be improved, and the joint fracture between the finger electrode and the bus electrode can be avoided.

While the present invention has been described above by way of example, it is not intended to be construed as a limitation of the scope of the invention. Therefore, the scope of the invention is defined by the scope of the appended claims.

202b‧‧‧Solar cell structure

204‧‧‧Substrate

206‧‧‧ first surface

210b‧‧‧first electrode

212‧‧‧First bus electrode

216‧‧‧Second bus electrode

224a‧‧‧first finger electrode

224b‧‧‧second finger electrode

226a‧‧‧First auxiliary electrode

226b‧‧‧second auxiliary electrode

228a‧‧‧First auxiliary conductor

228b‧‧‧Second auxiliary conductor

232‧‧‧Electrode

234‧‧‧ interval

236‧‧‧ Extension direction

238‧‧‧

240‧‧‧

242‧‧‧

244‧‧‧

Claims (17)

A solar cell structure comprising: a substrate having a first surface and a second surface; a first electrode disposed on the first surface and comprising at least one first bus electrode and a plurality of finger electrodes And a plurality of first auxiliary electrodes, wherein the finger electrodes intersect the at least one first bus electrode, the first auxiliary electrodes do not intersect the at least one first bus electrode; and a second electrode is disposed at the The second surface includes at least one second bus electrode, and the at least one second bus electrode includes a plurality of electrode portions corresponding to the first auxiliary electrodes, wherein the electrode portions are along the at least one first bus electrode An extending direction is arranged at intervals, and each of the electrode portions is orthographically projected to overlap the at least one first bus electrode, and further than the orthographic projections are formed in the extending direction to form a plurality of intervals, wherein the fingers are The electrode includes a plurality of first finger electrodes, the first finger electrodes intersecting the orthographic projections, and each of the first auxiliary electrodes is located on a side of the orthographic projection corresponding to the electrode portion And with the corresponding orthogonal projection of the intersection of the first finger electrode intersect. The solar cell structure of claim 1, wherein the plurality of finger electrodes further comprise a plurality of second finger electrodes located in the spaces, and one end of each of the first auxiliary electrodes protrudes adjacent to the adjacent orthographic projection In the interval of one end, and intersecting the second finger electrode adjacent to the corresponding orthographic projection in the interval in which the protrusion is projected. The solar cell structure of claim 2, wherein the other end of each of the first auxiliary electrodes protrudes in the interval adjacent to the other end of the corresponding orthographic projection, and is adjacent to the corresponding interval The second finger electrodes of the orthographic projection intersect. The solar cell structure of claim 1, wherein the first electrode further comprises a plurality of first auxiliary wires corresponding to the first auxiliary electrodes, and each of the first auxiliary wires is connected to the first auxiliary electrode and The at least one first bus electrode. The solar cell structure of claim 4, wherein each of the first auxiliary wires has a width greater than a width of each of the finger electrodes, and each of the first auxiliary wires does not intersect the adjacent ones of the finger electrodes. The solar cell structure of claim 1, wherein the first electrode further comprises a plurality of second auxiliary electrodes, wherein the second auxiliary electrodes do not intersect the at least one first bus electrode, and the first auxiliary Corresponding to the electrodes, each of the second auxiliary electrodes and the corresponding first auxiliary electrode are respectively located on opposite sides of the orthographic projection of the corresponding electrode portion. The solar cell structure of claim 6, wherein the first electrode further comprises a plurality of second auxiliary wires corresponding to the second auxiliary electrodes, and each of the second auxiliary wires is connected to the second auxiliary electrode and The at least one first bus electrode. The solar cell structure of claim 6, wherein each of the second auxiliary electrodes and the corresponding first auxiliary electrode are respectively located outside the opposite edges of the orthographic projection of the corresponding electrode portion along the extending direction. A solar cell module comprising: an upper plate; a lower plate; a plurality of solar cell structures according to any one of claims 1-8, disposed between the upper plate and the lower plate; a plurality of connecting strips, Electrically connecting adjacent solar cell structures; At least one layer of encapsulating material is located between the upper plate and the lower plate, and the solar cell structures are combined with the upper plate and the lower plate. A method of fabricating a solar cell structure, comprising: providing a substrate having a first surface and a second surface; forming a first electrode on the first surface, wherein the first electrode comprises at least one a bus electrode, a plurality of finger electrodes, and a plurality of first auxiliary electrodes, the finger electrodes intersecting the at least one first bus electrode, and the first auxiliary electrodes do not intersect the at least one first bus electrode; And forming a second electrode on the second surface, wherein the second electrode comprises at least one second bus electrode, the at least one second bus electrode comprising a plurality of electrode portions corresponding to the first auxiliary electrodes, the electrodes The portion is spaced along the extending direction of one of the at least one first bus electrodes, and each of the electrode portions is orthographically projected to overlap the at least one first bus electrode, and further than the orthographic projections are in the extending direction Forming a plurality of intervals, wherein the finger electrodes include a plurality of first finger electrodes, the first finger electrodes intersecting the orthographic projections, and each of the first auxiliary electrodes Located beside the corresponding side of the orthogonal projection of the portion of the electrode, and with the corresponding orthogonal projection of the intersection of the first finger electrode intersect. The method of fabricating a solar cell structure according to claim 10, wherein the step of forming the first electrode further comprises: causing the finger electrodes to include a plurality of second finger electrodes, wherein the second finger electrodes are located at the intervals One end of each of the first auxiliary electrodes protrudes in the interval adjacent to one end of the corresponding orthographic projection, and intersects the second finger electrode adjacent to the corresponding orthographic projection in the interval in which the protrusion is projected. A method of manufacturing a solar cell structure according to claim 11, The other end of each of the first auxiliary electrodes protrudes in the interval adjacent to the other end of the corresponding orthographic projection, and intersects the second finger electrode adjacent to the corresponding orthographic projection in the protruding interval . The method of manufacturing the solar cell structure of claim 10, wherein the step of forming the first electrode further comprises: causing the first electrode to include a plurality of first auxiliary wires corresponding to the first auxiliary electrodes, each first The auxiliary wire is connected to the first auxiliary electrode and the at least one first bus electrode. The method of fabricating a solar cell structure according to claim 13, wherein a width of each of the first auxiliary wires is greater than a width of each of the finger electrodes. The method of fabricating a solar cell structure according to claim 10, wherein the step of forming the first electrode further comprises: causing the first electrode to include a plurality of second auxiliary electrodes, the second auxiliary electrodes and the at least one first confluent The electrodes do not intersect, and corresponding to the first auxiliary electrodes, each of the second auxiliary electrodes and the corresponding first auxiliary electrode are respectively located on opposite sides of the orthographic projection of the corresponding electrode portion. The method of fabricating a solar cell structure according to claim 15, wherein the step of forming the first electrode further comprises: causing the first electrode to include a plurality of second auxiliary wires corresponding to the second auxiliary electrodes, each second The auxiliary wire is connected to the second auxiliary electrode and the at least one first bus electrode. The method for manufacturing a solar cell structure according to claim 15, wherein each of the second auxiliary electrodes and the corresponding first auxiliary electrode are respectively located at opposite edges of the orthographic projection of the corresponding electrode portion along the extending direction. The outside.