Thin film photovoltaic module
By setting diodes in thin-film photovoltaic modules and connecting them in reverse parallel with the cells, the problem of cell breakdown due to shading is solved, enabling normal use of the cells and improving power generation performance after shading is removed.
Patent Information
- Application Number
- CN202520066572.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-10
- Publication Date
- 2026-01-09
- Estimated Expiration
- 2035-01-10
AI Technical Summary
When thin-film photovoltaic modules are shaded, the shaded cells are prone to reverse breakdown, leading to a decrease in power generation performance and irreversible losses.
In thin-film photovoltaic modules, diodes are connected in reverse parallel with some cells to ensure that the diodes conduct when the number of shaded cells reaches a certain amount, thus bypassing the shaded cells to prevent breakdown, and the parallel cell strings provide protection against hot spots.
It effectively prevents the battery from being damaged by shading, ensuring that the battery can be used normally after the shading is removed, thus improving the power generation performance of thin-film photovoltaic modules and avoiding power generation loss and current mismatch.
Smart Images
Figure CN223786409U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The embodiment of the utility model relates to the technical field of photovoltaic power generation, especially relates to a thin film photovoltaic module. BACKGROUND
[0002] The thin film photovoltaic module is arranged in the external environment, and is easily affected by the shadow to block the light. When the shadow blocks part of the cells, the blocked cells are subjected to reverse bias by the unblocked cells, and the blocked cells are easily reversely broken down, so that the blocked cells cannot be recovered after the shadow is removed, the power generation performance of the thin film photovoltaic module is affected, and the power generation capacity is lost. CONTENT
[0003] The utility model provides a kind of thin film photovoltaic module, to improve the phenomenon that cell is reversely broken down when thin film photovoltaic module is blocked, guarantee the power generation performance of thin film photovoltaic module, improve the stability and reliability of thin film photovoltaic module.
[0004] In the first aspect, the utility model provides a kind of thin film photovoltaic module, including multiple series connection cells, multiple the cell is arranged in AxB array, wherein, A and B are all integer greater than or equal to 2;The thin film photovoltaic module further includes at least one diode;Each the diode is reversely connected in parallel with at least part of the cell;When the number of anti-hot spot cell is n, the product of the bias voltage of the cell and n minus the on-voltage of the diode is greater than the product of the number of cell connected with the diode minus n and the output voltage of the cell;Wherein, n is integer greater than or equal to 1.
[0005] Optionally, each row of the cell is connected in series with other rows of the cell;The diode is reversely connected in parallel with at least part of the row of the cell;
[0006] Or, each column of the cell is connected in series with other columns of the cell;The diode is reversely connected in parallel with at least part of the column of the cell.
[0007] Optionally, the cell corresponding to the connection of the diode includes p×q;Wherein, p is the number of rows of the cell corresponding to the connection of the diode, q is the number of each row of the cell;P is integer greater than or equal to 1, q is integer greater than or equal to 2;The difference between the product of the bias voltage of the cell and p and the product of the output voltage of the cell and p×q-p is greater than the on-voltage of the diode;The difference between the product of the bias voltage of the cell and q and the product of the output voltage of the cell and p×q-q is greater than the on-voltage of the diode.
[0008] Optionally, the number of rows of the cell corresponding to the connection of different diodes is equal.
[0009] Optionally, the positive electrode of the first battery in the first row of the batteries is used as the positive electrode of the thin-film photovoltaic module, and the negative electrode of the first battery in the last row of the batteries is used as the negative electrode of the thin-film photovoltaic module; the last battery in the previous row of the batteries is connected with the last battery in the next row of the batteries, the first battery in the next row of the batteries is connected with the first battery in the row after the next row of the batteries; the cathode of the diode is connected with the first battery in the first row of the batteries connected in correspondence, and the anode of the diode is connected with the first battery in the last row of the batteries connected in correspondence.
[0010] Optionally, the battery comprises a first electrode layer, a first charge transport layer, a power generation functional layer, a second charge transport layer, and a second electrode layer arranged in layers; the battery further comprises an extension part, which is formed integrally with the second electrode layer; the extension part of one battery is in contact with the first electrode layer of an adjacent battery.
[0011] Optionally, the battery further comprises a first conductive wire, which is arranged on the second electrode layer.
[0012] Optionally, the battery further comprises a second conductive wire, which is arranged in the same layer as the first conductive wire and intersects the first conductive wire.
[0013] Optionally, the material of the first conductive wire and the second conductive wire comprises low-temperature conductive glue; wherein the low-temperature curing temperature of the low-temperature conductive glue is less than or equal to 200℃.
[0014] Optionally, the thin-film photovoltaic module further comprises a substrate and an encapsulation layer, the first electrode layer is arranged on the substrate, and the encapsulation layer covers the first conductive wire and the second electrode layer, for encapsulating a plurality of the batteries.
[0015] The technical scheme of the embodiment of the utility model discloses, through setting up diode and at least partial battery reverse parallel connection, when the number of heat spot prevention battery is n, the product of the bias voltage of battery and n minus the on voltage of diode is greater than the product of the output voltage of battery after the number of battery connected by diode minus n, thereby when the number of battery shaded by shadow is greater than or equal to n, diode can be turned on, and the voltage between the battery shaded by shadow is less than the bias voltage of battery, thereby on the basis of ensuring that the battery shaded by shadow is not broken down, the current in the battery string connected by diode is bypassed, diode can prevent heat spot for the battery string reverse parallel connection, avoid the damage of non-recoverable caused by battery breakdown, when the battery shaded by shadow can be normally used after the shadow is removed, improve the power generation performance of thin film photovoltaic module, avoid the power generation loss of thin film photovoltaic module.Simultaneously when diode is turned on, the current of battery outside the battery string connected by diode can be avoided, thereby the current mismatch phenomenon of thin film photovoltaic module can be avoided. BRIEF DESCRIPTION OF DRAWINGS
[0016] Figure 1 A structure schematic view that a thin film photovoltaic module is shaded by shadow along the direction perpendicular to the arrangement of battery is provided for related technologies;
[0017] Figure 2 A structure schematic view that a thin film photovoltaic module is shaded by shadow along the direction parallel to the arrangement of battery is provided for related technologies;
[0018] Figure 3 A structure schematic view of thin film photovoltaic module is provided for the embodiment of the utility model;
[0019] Figure 4 A structure schematic view that a thin film photovoltaic module is shaded by shadow along the direction perpendicular to the arrangement of battery is provided for the embodiment of the utility model;
[0020] Figure 5 A structure schematic view that a thin film photovoltaic module is shaded by shadow along the direction parallel to the arrangement of battery is provided for the embodiment of the utility model;
[0021] Figure 6 A voltage-current curve schematic view of battery is provided for the embodiment of the utility model;
[0022] Figure 7 Another cross-sectional structure schematic view of thin film photovoltaic module is provided for the embodiment of the utility model; DETAILED DESCRIPTION
[0023] The utility model will be made further detailed illustration below combining with the drawings and examples. It can be understood that the specific examples described here are only for explaining the utility model, and not for limiting the utility model. In addition, it needs to be explained that, in order to facilitate the description, only the part related to the utility model is shown in the drawings, not all structures.
[0024] Figure 1 A structure diagram that a thin-film photovoltaic module provided by the related art is shaded by a shadow along the direction perpendicular to the arrangement of the cells is shown. Figure 1 As shown in the figure, the thin-film photovoltaic module includes a plurality of cells 101 arranged along a first direction X and connected in series, and a plurality of parallel diodes 102, the cathode of the parallel diode 102 is connected with the positive pole + of the plurality of cells 101 connected in series, and the anode of the parallel diode 102 is connected with the negative pole - of the plurality of cells 101 connected in series. Figure 1 As shown in the figure, when the shadow is perpendicular to the first direction X and shades the cells 101, that is, the shadow decreases or increases along a second direction Y, the part of each cell 101 shaded by the shadow cannot generate current, so that the current generated by each cell 101 decreases according to the shading ratio. At this time, the positive pole potential of the cells 101 connected in series is greater than the negative pole potential of the cells 101 connected in series, and the parallel diode 102 will not be turned on, causing the current mismatch of the entire cells 101 connected in series, so that the power generation of the thin-film photovoltaic module is reduced. Figure 2 A structure diagram that a thin-film photovoltaic module provided by the related art is shaded by a shadow along the direction parallel to the arrangement of the cells is shown. Figure 2 As shown in the figure, when the shadow is parallel to the first direction X and shades the cells 101, that is, the shadow decreases or increases along the first direction X, it is easy to appear that at least one cell 101 is completely shaded. At this time, the shaded cell 101 is subjected to reverse bias by the unshaded cell 101, and the shaded cell 101 is easy to be broken down before the parallel diode 102 is turned on. After the shadow is removed, the broken-down cell 101 cannot be recovered, causing the loss of the electrical performance of the thin-film transistor. For example, the thin-film photovoltaic module includes 81 cells 101 connected in series. When the shadow shades one cell 101, the cell 101 is broken down by the bias applied by the other cells 101, so that the voltage drop across the cell 101 is the bias voltage when the cell 101 is broken down, for example, 5V. Then when the number of cells 101 shaded by the shadow reaches 14, the parallel diode 102 is turned on. Therefore, before the number of cells 101 shaded by the shadow reaches 14, the shaded cells 101 are all in the state of being broken down, and cannot be recovered after the shadow is removed, causing the loss of the electrical performance of the thin-film transistor about 17%.
[0025] In view of the above technical problems, the utility model embodiment provides a thin-film photovoltaic module. Figure 3A structure diagram of a thin-film photovoltaic module is provided in the embodiment of the present application. Figure 3 As shown in the figure, the thin-film photovoltaic module comprises a plurality of series-connected cells 110, and the plurality of cells 110 are arranged in an AxB array, wherein A and B are both integers greater than or equal to 2; the thin-film photovoltaic module further comprises at least one diode 120; each diode 120 is connected in reverse parallel with at least part of the cells 110; when the number of anti-hot-spot cells is n, the product of the bias voltage of the cell 110 and n minus the on-voltage of the diode 120 is greater than the product of the number of cells connected with the diode 120 minus n and the output voltage of the cell 110; wherein n is an integer greater than or equal to 1.
[0026] Specifically, Figure 3 The plurality of cells 110 are arranged in a 6*5 array in the figure.When the plurality of cells 110 are connected in series, the current in each cell 110 is equal, and the voltage of the thin-film photovoltaic module is the sum of the output voltages of each cell 110. The output voltage of the cell 110 is the voltage output when the cell 110 converts light energy into electrical energy without being blocked. For example, the output voltage Voc of the cell 110 can be 1.1V.
[0027] When the diode 120 is connected in reverse parallel with at least part of the cells 110, the diode 120 can be connected in reverse parallel with at least part of the series-connected cell strings. That is, the cathode of the diode 120 is connected with the anode of the corresponding series-connected cell string, and the anode of the diode 120 is connected with the cathode of the corresponding series-connected cell string. Figure 3 Figure 3 For example, as shown in the figure, one diode 120 is connected in reverse parallel with 10 cells 110, the cathode of the diode 120 is connected with the anode of the 10 series-connected cells 110, and the anode of the diode 120 is connected with the cathode of the 10 series-connected cells 110.
[0028] When the thin-film photovoltaic module is blocked by a shadow, the blocked cells 110 cannot generate electrical energy, and are subjected to a reverse bias by the unblocked cells 110, so that the blocked cells 110 appear to be hot spots of the thin-film photovoltaic module. The number of anti-hot-spot cells is the number of blocked cells corresponding to the on-voltage of the diode 120 when the cells 110 are blocked by a shadow. The bias voltage V1 of the cell 110 is the breakdown voltage required between the two ends of the cell 110 when the cell 110 is broken down.
[0029] When the number of the shadow-shielded cells 110 is less than n, the number of the shadow-shielded cells 110 is relatively small, and the number of the un-shielded cells 110 is relatively large. When the output voltage of the un-shielded cells 110 is applied to the shadow-shielded cells 110, the shadow-shielded cells 110 are easily broken down. The anode voltage of the diode 120 is the product of the number of the shadow-shielded cells and the bias voltage of the cell 110, i.e., V1*r, where r is the number of the shadow-shielded cells. The cathode voltage of the diode 120 is the product of the number of the un-shielded cells and the output voltage of the cell 110, i.e., (m-r)*Voc, where m is the number of the cells in the cell string to which the diode 120 is connected. At this time, the difference between the anode voltage and the cathode voltage of the diode 120 is less than the conduction voltage of the diode 120, i.e., V1*r-(m-r)*Voc<Vd, where Vd is the conduction voltage of the diode 120. Therefore, the diode 120 cannot be turned on, and the hot-spot protection cannot be started.
[0030] When the number of the shadow-shielded cells 110 is n, under the condition that the shadow-shielded cells 110 are broken down, the anode voltage of the diode 120 can be the product of the number of the shadow-shielded cells and the bias voltage between the shadow-shielded cells 110, i.e., V1*n. The cathode voltage of the diode 120 can be the product of the number of the un-shielded cells and the output voltage of the cell 110, i.e., (m-n)*Voc. The product of the bias voltage of the cell 110 and n minus the conduction voltage of the diode 120 is greater than the product of the number of the cells connected to the diode 120 minus n and the output voltage of the cell 110, i.e., V1*n-Vd>(m-n)*Voc, where m is the number of the cells in the cell string to which the diode 120 is connected, Voc is the output voltage of the cell 110 when the cell 110 normally generates electricity, and Vd is the conduction voltage of the diode 120. At this time, the anode voltage of the diode 120 minus the cathode voltage of the diode 120 is greater than the conduction voltage of the diode 120, and the diode 120 is turned on. At this time, the voltage between the shadow-shielded cells 110 is [(m-n)*Voc+Vd] / n, which is less than the bias voltage of the cell 110, thereby bypassing the current in the cell string to which the diode 120 is connected on the premise that the shadow-shielded cells 110 are not broken down, so that the diode 120 can protect the reverse-parallel cell string from the hot spot, avoid the irreversible damage caused by the breakdown of the cell 110, and improve the power generation performance of the thin-film photovoltaic module when the shadow-shielded cells 110 can be normally used after the shadow is removed, thereby avoiding the loss of the power generation of the thin-film photovoltaic module. At the same time, the current of the cells outside the cell string to which the diode 120 is connected can be prevented from being reduced when the diode 120 is turned on, thereby avoiding the current mismatch of the thin-film photovoltaic module. Wherein n is an integer greater than or equal to 1, and the number of the hot-spot protection cells can be set according to the requirement of the hot-spot protection.
[0031] Exemplary, Figure 4 A structure schematic view of a thin-film photovoltaic module provided by the embodiment of the present application is shown in Fig. 1, in which the thin-film photovoltaic module is shaded by a shadow along a direction perpendicular to the arrangement of the cells. Figure 5 A structure schematic view of a thin-film photovoltaic module provided by the embodiment of the present application is shown in Fig. 2, in which the thin-film photovoltaic module is shaded by a shadow along a direction parallel to the arrangement of the cells. Figure 4 and Figure 5 As shown in Figs. 1 and 2, the thin-film photovoltaic module includes three diodes 120. When m is 10, n is 2, Voc is 1.1 V, V1 is 5 V, and Vd is 0.7 V, the anode voltage of the first diode 120 can be the product of the number of the shaded cells 2 and the bias voltage V1 across the shaded cells 110, i.e. 5*2=10 V, under the condition that the shaded cells 110 are broken down when the shadow shades the first diode 120 corresponding to the connection of the two cells 110 in the first cell string. The cathode voltage of the first diode 120 can be the product of the number of the unshaded cells and the output voltage of the cells 110, the number of the unshaded cells is m-n=10-2=8, and the output voltage Voc=1.1 V, so the cathode voltage of the first diode 120 is (m-n)*Voc=8.8 V. At this time, the difference between the anode voltage and the cathode voltage of the first diode 120 is 10-8.8=1.2 V, which is greater than the on-voltage 0.7 V of the diode 120, so the first diode 120 is turned on to bypass the 10 cells 110 in the first cell string. At this time, the voltage across the two shaded cells 110 is [(m-n)*Voc+Vd] / n= [(10-2)*1.1+0.7] / 2=4.75 V, which is less than the bias voltage 5 V of the cells 110, thereby avoiding the two shaded cells 110 from being broken down, so that the diode 120 can protect the reverse-parallel cell string from hot spot, avoid the irreversible damage caused by the breakdown of the cells 110, and improve the power generation performance of the thin-film photovoltaic module and avoid the loss of the power generation of the thin-film photovoltaic module. Meanwhile, the current of the cells corresponding to the other two diodes 120 can be reduced, and the current mismatch of the thin-film photovoltaic module can be avoided. In some embodiments, when the shadow shades 5 cells 110, the diode 120 can also be activated, at this time, the voltage across the 5 shaded cells 110 is [(m-5)*Voc+Vd] / n= [(10-5)*1.1+0.7] / 5≈1.2 V, which can also avoid the 5 shaded cells 110 from being broken down. In some embodiments, the number of the cells corresponding to the connection of the diode 120 ranges from 4 to 30.
[0032] The technical scheme of the embodiment is that the diode is connected in reverse parallel with at least part of the batteries, when the number of the heat spot prevention batteries is n, the product of the bias voltage of the battery and n minus the turn-on voltage of the diode is greater than the product of the number of the batteries connected by the diode minus n and the output voltage of the battery, so that when the number of the shadow-shielded batteries is greater than or equal to n, the diode can be turned on, and the voltage across the shadow-shielded battery is less than the bias voltage of the battery, so that the current in the battery string connected by the diode can be bypassed on the premise that the shadow-shielded battery is not broken down, the diode can prevent the heat spot of the battery string connected in reverse parallel, the irreparable damage caused by the breakdown of the battery is avoided, when the shadow is removed and the shadow-shielded battery can be normally used, the power generation performance of the thin-film photovoltaic module is improved, and the power generation loss of the thin-film photovoltaic module is avoided. At the same time, when the diode is turned on, the current of the battery outside the battery string connected by the diode can be prevented from being reduced, so that the current mismatch phenomenon of the thin-film photovoltaic module can be avoided.
[0033] With reference to the foregoing Figures 3 to 5 , the batteries 110 in each row are connected in series and connected in series with other rows of batteries 110; the diode 120 is connected in reverse parallel with at least part of the row of batteries 110; or, the batteries 110 in each column are connected in series and connected in series with other columns of batteries 110; the diode 120 is connected in reverse parallel with at least part of the column of batteries 110.
[0034] Specifically, Figures 3 to 5 An exemplary embodiment is shown in which the batteries 110 in each row are connected in series and connected in series with other rows of batteries 110, realizing the series connection of all the batteries 110. The diode 120 is connected in reverse parallel with at least part of the row of batteries 110. After determining the number n of the heat spot prevention batteries, the number of the batteries connected by the diode 120 can be set according to the turn-on voltage of the diode 120 and the output voltage and bias voltage of the battery 110, so that the product of the bias voltage of the battery 110 and n minus the turn-on voltage of the diode 120 is greater than the product of the number of the batteries connected by the diode 120 minus n and the output voltage of the battery 110. When the battery 110 connected by the diode 120 is shadow-shielded, the diode can be turned on before the shadow-shielded battery 110 is broken down, so that the battery can be protected against heat spots, the irreparable damage caused by the breakdown of the battery 110 is avoided, when the shadow is removed and the shadow-shielded battery 110 can be normally used, the power generation performance of the thin-film photovoltaic module is improved, and the power generation loss of the thin-film photovoltaic module is avoided. Exemplarily, when n is 2, Voc is 1.1V, V1 is 5V, and Vd is 0.7V, the number m of the batteries connected by each diode 120 can be set to 10.
[0035] In addition, Figure 6The utility model provides a voltage - current curve schematic drawing of battery for the embodiment of the utility model. Among them, the abscissa is voltage, ordinate is current, V1 is the bias voltage of battery, Voc is the output voltage of battery, N is the number of battery in thin film photovoltaic module, Impp is the current in battery 110, curve 1 is the area proportion of battery is shaded is relatively big, curve 2 is the area proportion of battery is shaded is relatively small, curve 3 is the voltage - current curve of battery, curve 4 is the voltage - current curve of thin film photovoltaic module. The area proportion of battery is shaded is the area of battery is shaded and the area of battery itself can receive light energy and carry out photoelectric conversion. When multiple battery 110 array arrangement, under the same shaded area, the area proportion of each battery is shaded, relative to the technical scheme of battery in thin film photovoltaic module provided by the related art is arranged in a row, the area proportion of each battery is shaded is small, is favorable to improve the difficulty of battery breakdown, thereby can reduce the probability of battery breakdown. When can normally use after shadow removal, improve the power generation performance of thin film photovoltaic module, avoid the power generation loss of thin film photovoltaic module.
[0036] In some embodiments, as shown in Figures 3 to 5 The anode of the first battery 110 of the first row of batteries 110 serves as the anode V+ of the thin film photovoltaic module, and the cathode of the first battery 110 of the last row of batteries 110 serves as the cathode V- of the thin film photovoltaic module; the last battery 110 of the previous row of batteries 110 is connected to the last battery 110 of the next row of batteries 110, the first battery 110 of the next row of batteries 110 is connected to the first battery 110 of the row below, the cathode of the diode 120 is connected to the first battery of the first row of batteries, and the anode of the diode is connected to the first battery of the last row of batteries.
[0037] Specifically, as shown in Figures 3 to 5As shown, the first row of batteries 110 includes first to fifth batteries 1111-1115 connected in series along the first direction X, respectively, the second row of batteries 110 includes sixth to tenth batteries 1121-1125 connected in series along the first direction X, respectively, the third row of batteries 110 includes eleventh to fifteenth batteries 1131-1135 connected in series along the first direction X, respectively, the fourth row of batteries 110 includes sixteenth to twentieth batteries 1141-1145 connected in series along the first direction X, respectively, the fifth row of batteries 110 includes twenty-first to twenty-fifth batteries 1151-1155 connected in series along the first direction X, respectively, and the sixth row of batteries 110 includes twenty-sixth to thirtieth batteries 1161-1165 connected in series along the first direction X, respectively. The positive electrode of the first battery 1111 is the positive electrode V+ of the thin-film photovoltaic module, and the fifth battery 1115 is connected with the tenth battery 1125, the sixth battery 1121 is connected with the eleventh battery 1131, the fifteenth battery 1135 is connected with the twentieth battery 1145, the sixteenth battery 1141 is connected with the twenty-first battery 1151, the twenty-fifth battery 1155 is connected with the thirtieth battery 1165, and the negative electrode of the twenty-sixth battery 1161 is the negative electrode V- of the thin-film photovoltaic module, so as to realize the series connection of the first row of batteries 110 and the sixth row of batteries 110. When each diode 120 is connected with two rows of batteries 110, the cathode of the first diode 120 is connected with the anode of the first battery 1111 of the first row, and the cathode of the first diode 120 is connected with the cathode of the first battery 1121 of the second row, so as to realize the anti-parallel connection of the first diode 120 and the two rows of batteries 110. Similarly, the cathode of the second diode 120 is connected with the anode of the first battery 1131 of the third row, and the cathode of the second diode 120 is connected with the cathode of the first battery 1141 of the fourth row, so as to realize the anti-parallel connection of the second diode 120 and the two rows of batteries 110. The cathode of the third diode 120 is connected with the anode of the first battery 1151 of the fifth row, and the cathode of the third diode 120 is connected with the cathode of the first battery 1161 of the sixth row, so as to realize the anti-parallel connection of the third diode 120 and the two rows of batteries 110.
[0038] It should be noted that in other embodiments, each column of batteries 110 can also be connected in series and then connected in series with other columns of batteries 110, and the series connection of all batteries 110 can also be achieved. The diode 120 is connected in anti-parallel with at least part of the column of batteries 110, and the number of batteries connected by the diode 120 can also be set according to the number of anti-hot spot batteries n, the on-voltage of the diode 120, and the output voltage and bias voltage of the battery 110, so that the product of the bias voltage of the battery 110 and n minus the on-voltage of the diode 120 is greater than the product of the number of batteries connected by the diode 120 minus n and the output voltage of the battery 110. When the shadow blocks the battery 110 connected by the diode 120, the diode 120 can be turned on before the blocked battery 110 is broken down, thereby protecting the battery from hot spots and avoiding irreversible damage caused by the breakdown of the battery 110. When the blocked battery 110 can be used normally after the shadow is removed, the power generation performance of the thin-film photovoltaic module is improved, and the power generation loss of the thin-film photovoltaic module is avoided.
[0039] With continued reference to Figures 3 to 5 , the battery 110 connected by the diode 120 includes p x q; wherein p is the number of rows of batteries connected by the diode 120, and q is the number of batteries in each row; p is an integer greater than or equal to 1, and q is an integer greater than or equal to 2; the product of the bias voltage of the battery 110 and p is greater than the difference between the output voltage of the battery 110 and the product of p x q - p; the product of the bias voltage of the battery 110 and q is greater than the difference between the output voltage of the battery 110 and the product of p x q - q.
[0040] Specifically, when the battery 110 connected by the diode 120 includes p x q, the diode 120 connects p rows of batteries 110, and the number of batteries in each row is q. At this time, V1*P - (P x Q - P) * Voc > Vd can be set, where V1 is the bias voltage of the battery 110, Voc is the output voltage of the battery 110, and Vd is the on-voltage of the diode 120. As shown in Figure 4 When the shadow blocks the battery 110 along the direction perpendicular to the arrangement of the battery, the anode voltage minus the cathode voltage of the diode 120 can be greater than the on-voltage of the diode 120, and the diode 120 is in the on state. At the same time, the voltage across the blocked battery 110 can be less than the bias voltage, thereby protecting the battery 110 from hot spots when the shadow blocks the battery 110 along the direction perpendicular to the arrangement of the battery, avoiding irreversible damage caused by the breakdown of the battery 110. When the blocked battery 110 can be used normally after the shadow is removed, the power generation performance of the thin-film photovoltaic module is improved, and the power generation loss of the thin-film photovoltaic module is avoided. Exemplarily, Figure 4In the example shown in FIG. 1, p is 2 and q is 5.
[0041] At the same time, V1*q-(p*q-q)*Voc>Vd can be set, where V1 is the bias voltage of the battery 110, Voc is the output voltage of the battery 110, and Vd is the on voltage of the diode 120. As shown in FIG. 2, when the shadow shields the battery 110 along the direction parallel to the arrangement of the battery, the anode voltage of the diode 120 minus the cathode voltage is greater than the on voltage of the diode 120, and the diode 120 is in the on state. At the same time, the voltage across the shielded battery 110 is less than the bias voltage, so that the battery 110 can be protected from hot spots when the shadow shields the battery 110 along the direction perpendicular to the arrangement of the battery, avoiding the non-recoverable damage caused by the breakdown of the battery 110. When the shielded battery 110 can be used normally after the shadow is removed, the power generation performance of the thin-film photovoltaic module is improved, and the power generation loss of the thin-film photovoltaic module is avoided. In the example shown in FIG. 2, p is 2 and q is 5. Figure 5 Figure 5 In the example shown in FIG. 2, p is 2 and q is 5.
[0042] In some embodiments, the number of battery rows connected by different diodes is equal.
[0043] Specifically, when the thin-film photovoltaic module includes a plurality of diodes, the number of battery rows connected by different diodes is equal, so that the number of batteries connected by each diode is equal. At this time, different diodes can have the same effect of preventing hot spots on all batteries, ensuring the consistency of the overall hot spot prevention effect of the thin-film photovoltaic module.
[0044] Figure 7 A cross-sectional structure schematic diagram of a thin-film photovoltaic module provided by the embodiment of the present application is shown in FIG. 3. Figure 7 As shown in FIG. 3, the battery 110 includes a first electrode layer 111, a first charge transport layer 112, a power generation functional layer 113, a second charge transport layer 114, and a second electrode layer 115 arranged in layers. The battery further includes an extension 116, which is formed integrally with the second electrode layer 115. The extension 116 of one battery 110 is in contact with the first electrode layer 115 of an adjacent battery 110.
[0045] Specifically, the material of the second electrode layer 115 can be a transparent electrode material, which ensures the transmittance when external light is incident on the surface of the side of the second electrode layer 115 away from the second charge transport layer 114. For example, the second electrode layer 115 can be a transparent conductive oxide, which ensures the light transmittance and conductivity of the second electrode layer. For example, the transparent conductive oxide can be Fluorine-doped Tin Oxide (FTO), Indium Tin Oxide (ITO), Aluminum Zinc Oxide (AZO), Indium Tungsten Oxide (IWO), etc. Then the light is incident on the power generation functional layer 113 after passing through the second electrode layer 115 and the second charge transport layer 114, so that the power generation functional layer 113 can generate new hole-electron pairs. The direction of the p-n junction electric field in the power generation functional layer 113 points to the p region. When the direction of the p-n junction electric field in the power generation functional layer 113 points to the second charge transport layer 114, the electrons are transported to the first electrode layer 111 through the first charge transport layer 112, and the holes are transported to the second electrode layer 115 through the second charge transport layer 114, so as to form an electric field between the first electrode layer 111 and the second electrode layer 115, so as to form a certain potential difference between the two electrodes of the battery 110, i.e. the voltage that the battery 110 can provide. For example, the output voltage of the battery 110 can be 1.1 V. At this time, the first electrode layer 111 can be the negative electrode of the battery 110, and the second electrode layer 115 can be the positive electrode of the battery 110. The first charge transport layer 112 is an electron transport layer, and the second charge transport layer 114 is a hole transport layer. In other embodiments, the direction of the p-n junction electric field in the power generation functional layer 113 can point to the first charge transport layer 112. At this time, the transport directions of the holes and the electrons are exchanged. The first electrode layer 111 of the battery 110 is the positive electrode of the battery 110, the second electrode layer 115 is the negative electrode of the battery 110, the first charge transport layer 112 is a hole transport layer, and the second charge transport layer 114 is an electron transport layer. Here, no limitation is made.
[0046] The thin-film photovoltaic module includes a plurality of cells 110. When forming the plurality of cells 110, a first electrode film layer can be formed first, and then a first groove can be formed on the first electrode film layer by etching through laser scribing, so as to disconnect the first electrode layers 111 corresponding to adjacent cells 110. Then, a first charge transport film layer, a power generation functional film layer, and a second charge transport film layer can be formed on the first electrode layers 111 in sequence. Then, a second groove can be formed on the first charge transport film layer, the power generation functional film layer, and the second charge transport film layer by etching through laser scribing, so as to disconnect the first charge transport layers 112 corresponding to adjacent cells 110, disconnect the power generation functional layers 113 corresponding to adjacent cells 110, and disconnect the second charge transport layers 114 corresponding to adjacent cells 110. Then, a second electrode layer 115 and an extension 116 can be formed on the second charge transport layers 114 synchronously, and the extension 116 can be formed integrally, so that the second electrode layer 115 is connected with the extension 116. Meanwhile, the extension 116 can extend to the bottom of the second groove along the thickness direction Z of the first electrode layer 111 and be in contact with the first electrode layer 111, so that the first electrode layer 111 and the second electrode layer 115 are connected through the extension 116, realizing the series connection between adjacent cells 110, and avoiding the additional setting of a conductive wire, simplifying the process flow and difficulty of the series connection of the cells 110. Then, a third groove can be formed between adjacent cells 110 by laser scribing, so as to disconnect the second electrode layers 115 between adjacent cells 110.
[0047] In some embodiments, the material of the first electrode layer can include at least one of gold, silver, copper, aluminum, molybdenum, and transparent conductive oxide.
[0048] With reference to Figure 7 , the cell 110 further includes a first conductive wire 117 disposed on the second electrode layer 115.
[0049] Specifically, Figure 7The first conductive wire 117 is shown as extending along the first direction X. The first conductive wire 117 is disposed on the second electrode layer 115. The first conductive wire 117 can be disposed on the second electrode layer 115 by processes such as evaporation and screen printing. In some embodiments, when the thin-film photovoltaic module further includes an encapsulation film, the encapsulation film covers the second electrode layer 115, and the first conductive wire 117 can be a copper wire or a silver wire integrated with the encapsulation film and coupled to the second electrode layer 115 by lamination. When the adjacent cells 110 are connected in series along the first direction X, the transmission direction of the current on the second electrode layer 115 is the first direction X, and the transmission distance of the current on the second electrode layer 115 is the width of the cell 110 along the first direction X. At this time, the first conductive wire 117 extending along the first direction X is disposed on the second electrode layer 115, and the first conductive wire 117 is connected to the second electrode layer 115, so that the current can also pass through the first conductive wire 117. The first conductive wire 117 and the second electrode layer 115 are equivalent to being connected in parallel, thereby reducing the equivalent resistance when the current passes through the second electrode layer 115, and further reducing the power loss when the current passes through the second electrode layer 115, and improving the output power of the thin-film photovoltaic module. Moreover, the power loss can reduce the limitation on the width of each cell 110, which is conducive to reducing the number of cells 110 in the thin-film photovoltaic module, thereby reducing the cost caused by laser cutting in the manufacturing process of the cell 110, and reducing the impact of the depreciation of the laser equipment on the process. At the same time, the voltage of the thin-film photovoltaic module can be reduced, which is conducive to reducing the cost of the inverter in the photovoltaic power generation system, and further reducing the cost of electric energy. In addition, in some embodiments, the resistivity of the material of the first conductive wire 117 can be less than the resistivity of the transparent electrode material in the second electrode layer 115. When the first conductive wire 117 is disposed on the second electrode layer 115, the current on the second electrode layer 115 can be converged, further reducing the equivalent resistance when the current passes through the second electrode layer 115, and further reducing the power loss when the current passes through the second electrode layer 115. The material of the first conductive wire 117 can include metal.
[0050] With continued reference to Figure 7 , the cell 110 further includes a second conductive wire 118, which is disposed in the same layer as the first conductive wire 117 and intersects the first conductive wire 117.
[0051] In particular, Figure 7The second conductive lines 118 are shown as extending along the second direction Y in the figure. The second conductive lines 118 intersect the first conductive lines 117 and are arranged in the same layer, so that the second conductive lines 118 and the first conductive lines 117 form a mesh of conductive lines on the second electrode layer 115. This can further reduce the equivalent resistance of the current passing through the second electrode layer 115, thereby reducing the power loss of the current passing through the second electrode layer 115 and improving the output power of the thin-film photovoltaic module. The first conductive lines 117 and the second conductive lines 118 can be made of the same material, for example, both including metal. When the resistivity of the second conductive lines 118 is less than the resistivity of the second electrode layer 115, the current on the second electrode layer 115 can be converged, which can further reduce the power loss of the current passing through the second electrode layer 115 and improve the power of the thin-film photovoltaic module.
[0052] In some embodiments, the material of the first conductive lines 117 and the second conductive lines 118 includes low-temperature conductive glue, and the low-temperature conductive glue has a low-temperature curing temperature less than or equal to 200℃.
[0053] Specifically, the conductive glue can include a colloid and conductive particles. The material of the colloid can be a resin system, for example, including organic silicon, acrylic acid, and epoxy, etc., to ensure the light transmittance of the first conductive lines 117 and the second conductive lines 118. The material of the conductive particles can include metal such as gold, silver, copper, silver-coated copper, and silver-coated nickel, to ensure the conductivity of the first conductive lines 117 and the second conductive lines 118. Moreover, the low-temperature conductive glue has a low-temperature curing temperature less than or equal to 200℃, which is conducive to the curing of the first conductive lines 117 and the second conductive lines 118 during the manufacturing process.
[0054] In some embodiments, the thin-film photovoltaic module further includes a substrate and an encapsulation layer. The first electrode layer is arranged on the substrate, and the encapsulation layer covers the first conductive lines and the second electrode layer, and is used to encapsulate the plurality of cells.
[0055] Specifically, the substrate can be a back glass, which is used to protect and encapsulate other film layers of the cells. The encapsulation layer can include an encapsulation glue film and a front glass. The encapsulation glue film is used to encapsulate the cells, and the front glass can be used to protect other film layers of the cells.
[0056] It should be noted that the above only describes the preferred embodiments of the present application and the technical principles applied. Those skilled in the art will understand that the present application is not limited to the specific embodiments described herein, and those skilled in the art can make various obvious changes, re-adjustments and substitutions without departing from the scope of the present application. Therefore, although the present application has been described in detail through the above embodiments, the present application is not limited to the above embodiments, and can include more other equivalent embodiments without departing from the concept of the present application, and the scope of the present application is determined by the appended claims.
Claims
1. A thin film photovoltaic module, characterized by, The thin-film photovoltaic module comprises a plurality of series-connected batteries, and the plurality of batteries are arranged in an A×B array, wherein A and B are both integers greater than or equal to 2; the thin-film photovoltaic module further comprises at least one diode; each diode is connected in anti-parallel with at least part of the batteries; when the number of hot spot prevention batteries is n, the product of the bias voltage of the battery and n minus the on-voltage of the diode is greater than the product of the number of batteries connected with the diode minus n and the output voltage of the battery; wherein n is an integer greater than or equal to 1.
2. The thin-film photovoltaic module of claim 1, wherein, Each row of the batteries is connected in series with other rows of the batteries; the diode is connected in anti-parallel with at least part of the batteries in the row; Or, each column of the batteries is connected in series with other columns of the batteries; the diode is connected in anti-parallel with at least part of the batteries in the column.
3. The thin-film photovoltaic module of claim 2, wherein, The batteries corresponding to the connection of the diode include p×q; wherein p is the number of rows of batteries corresponding to the connection of the diode, and q is the number of batteries in each row; p is an integer greater than or equal to 1, and q is an integer greater than or equal to 2; the difference between the product of the bias voltage of the battery and p and the product of the output voltage of the battery and p×q-p is greater than the on-voltage of the diode; the difference between the product of the bias voltage of the battery and q and the product of the output voltage of the battery and p×q-q is greater than the on-voltage of the diode.
4. Thin-film photovoltaic module according to claim 2 or 3, characterized in that The number of rows of batteries corresponding to the connection of different diodes is equal.
5. The thin film photovoltaic module of claim 4, wherein, The positive electrode of the first battery in the first row of batteries is used as the positive electrode of the thin-film photovoltaic module, the negative electrode of the first battery in the last row of batteries is used as the negative electrode of the thin-film photovoltaic module; the last battery in the previous row of batteries is connected with the last battery in the next row of batteries, the first battery in the next row of batteries is connected with the first battery in the row below; the cathode of the diode is connected with the first battery in the first row of batteries corresponding to the connection, and the anode of the diode is connected with the first battery in the last row of batteries corresponding to the connection.
6. The thin film photovoltaic module of claim 1, wherein, The battery comprises a first electrode layer, a first charge transport layer, a power generation functional layer, a second charge transport layer, and a second electrode layer arranged in layers; the battery further comprises an extension part, which is formed integrally with the second electrode layer; the extension part of one battery is in contact with the first electrode layer of an adjacent battery.
7. The thin film photovoltaic module of claim 6, wherein, The battery further comprises a first conductive wire arranged on the second electrode layer.
8. The thin film photovoltaic module of claim 7, wherein, The battery further comprises a second conductive wire arranged in the same layer as the first conductive wire, and the second conductive wire intersects the first conductive wire.
9. The thin film photovoltaic module of claim 8, wherein, The materials of the first conductive wire and the second conductive wire comprise low-temperature conductive glue; wherein the low-temperature curing temperature of the low-temperature conductive glue is less than or equal to 200℃.
10. The thin film photovoltaic module of claim 7, wherein, Further comprising a substrate and an encapsulation layer, the first electrode layer is arranged on the substrate, and the encapsulation layer covers the first conductive wire and the second electrode layer, for encapsulating a plurality of batteries.