TWI494580B - Solar cell detection method and device thereof - Google Patents

Description

Cell sheet detecting method and device

The invention relates to a detecting method and device; in particular to a battery chip detecting method and device.

Generally, the current of the solar cell is taken out by a plurality of fine electrodes. If the cell of the cell is defective, the current is prevented from being output to the bus bar, and the energy cannot be collected. Since the resistance of the substrate is much larger than the resistance of the metal line

As shown in the first figure, the battery sheet 100 displays an electroluminescent (EL) pattern. In the EL pattern, some small bright spots or dark spots are often seen, and the dark points indicate that the current collection is difficult, such as at the dotted line A. But it is not easy to see the detailed location of the broken line. The EL pattern detection provides a forward bias voltage to the cell. When the current in the cell is circulated, a certain wavelength of light will be emitted. Therefore, it can be seen that the block that does not emit light may contain a problematic line. The problems are, for example, that the resistance of the blocks is too high, or that the substrate of the block is defective, such as a little bit of a dot in the dotted line A'.

Although the EL pattern can find out that the battery may have problems, but because of the black block generated in addition to the break, the material defect of the substrate itself will also be there. Therefore, the logic of the analysis (AY) is not easy to distinguish the difference between the broken line and the substrate defect, and the analysis program logic is too complicated and relatively expensive.

In addition, it is also possible to find out the broken line by means of shooting, but it is afraid that the screening will be too high when shooting. For example, there may be bending and shadows around the bus bar, and it is mistaken that the broken wire often has the problem of screening here, so it will be set to not detect. Around the busbar, but often around the busbar is the easiest to break. Moreover, the metal wires of the current battery sheets are getting thinner and thinner, and it is increasingly impossible to identify the broken wires with the naked eye. Therefore, the photography method still cannot completely and accurately find out where the battery may be broken.

One of the objects of the present invention is to provide a battery chip detecting method and device, It is possible to detect the degree of disconnection represented by the cell sheet, for example, in the shaded block of the EL pattern.

One of the objects of the present invention is to provide a battery chip detecting method and device, It does not need to use the EL pattern detection method to detect the number of broken lines or the degree of disconnection of the battery piece on the EL.

An embodiment of the present invention provides a battery chip detecting method, which includes the following Step: First, a battery piece is provided. The battery piece includes a plurality of bus bars, and any two bus bars include a plurality of metal wires. When measuring the efficiency of the cell, the cell is first measured by a solar simulator to obtain a first impedance value (series resistance). Next, the impedance of the plurality of metal lines between the two bus bars is detected to obtain a second impedance value of the total impedance of the plurality of metal wires. Comparing the first impedance value with the second impedance value produces a comparison result. Then, when the comparison result is greater than or equal to a preset value, it is determined that there is a predetermined number or more of disconnected lines between the two bus bars. An embodiment of the present invention provides a battery chip detecting device. The device comprises a first test unit, a second test unit, a comparison unit, and a determination unit. The first test unit is configured to detect a series resistance of the battery chip in the operation of detecting the battery chip to detect a first impedance value. The second test unit is configured to detect impedances of the plurality of metal lines between the two bus bars to obtain a second impedance value of the total impedance of the plurality of metal lines. The comparing unit compares the first impedance value with the second impedance value to produce a comparison result. When the comparison result is greater than or equal to a preset value, the judging unit judges that there are a predetermined number or more of disconnected lines between the two bus bars.

Another embodiment of the present invention provides a battery chip detecting method, including The following steps are as follows: First, a plurality of battery sheets having no disconnection or a number of broken wires smaller than a predetermined value are provided, each of the battery sheets includes a plurality of bus bars, and any two bus bars include a plurality of metal wires. The series resistance of each cell operating condition is detected to obtain a first impedance value. The impedance of the plurality of metal lines between the two bus bars of each cell is detected to obtain a second impedance value of the total impedance of the plurality of metal lines. Then, a first over-standard area is defined according to the first resistance value and the second resistance value obtained by each of the battery sheets. After that, the first resistance value and the second resistance value of the battery piece to be tested are measured, and whether the first resistance value and the second resistance value of the battery piece to be tested fall within the broken line exceeding the standard area to determine the battery piece to be tested. Whether the disconnection exceeds the standard.

The method and device for detecting a battery piece according to an embodiment of the present invention, using the detection series electric Resistance to metal line resistance, and comparison can detect whether the degree of disconnection of all or part of a cell is in conformity with specifications.

200‧‧‧cell test device

201, 202‧‧‧ test unit

203‧‧‧Comparative unit

204‧‧‧judging unit

BS1, BS2‧‧ ‧ busbar

M‧‧‧ metal wire

Figure 1 shows a schematic diagram of a conventional EL pattern.

Fig. 2A is a flow chart showing a method of detecting a battery chip according to an embodiment of the present invention.

Fig. 2B is a view showing a battery chip detecting device according to an embodiment of the present invention.

Figure 3 is a schematic diagram of a method for detecting series resistance and metal line resistance.

Fig. 4 is a table showing the composition of the first impedance value (series resistance) and the second impedance value (metal line resistance) according to an embodiment of the present invention.

FIG. 2A is a flow chart showing a method for detecting a battery chip according to an embodiment of the present invention. Fig. 2B shows a battery detecting device 200 according to an embodiment of the present invention. The battery detecting device 200 is for detecting a shadow or a broken line of, for example, the solar cell sheet 100 of Fig. 1. The battery detecting device 200 includes a first testing unit 201, a second testing unit 202, a comparing unit 203, and a determining unit 204. The embodiment of the first test unit 201 can be a series resistance RS cell test unit; one embodiment of the second test unit 202 can be a metal resistance RM metal. Resistance test unit.

Please refer to the 2A and 2B drawings at the same time. The following steps of the battery chip detecting method are as follows: Step S202: Start.

Step S204: providing a battery piece, the battery piece includes a plurality of bus bars, and any two bus bars BS1 and BS2 include a plurality of metal wires M, as shown in FIG.

Step S206: The first testing unit 201 detects that the battery piece is in an operating situation. The resistor is connected in series to obtain a first impedance value RS. For example, the first test unit 201 detects the battery piece to the left of the third drawing, and obtains the first impedance value RS. Please note that the first impedance value Rs=Rbulk+Remitter+Rcontact+Rmetal...(1) Rbulk is the impedance generated by the doping P-type doping concentration of the substrate, Remitter is the impedance generated by the N-type doping concentration of the cell, Rcontact represents the impedance between the substrate and the metal contact, and Rmetal is the impedance of the metal line. The measurement method of the first impedance value RS is derived from the change state of the current voltage (IV) curve under different light intensities (including under illumination). In the operating situation, the wire breakage of the fine electrode is very small for the first impedance value taken by the solar simulator.

Step S208: The second testing unit 202 detects the impedance of each metal line M of any two bus rows BS1, BS2, and the second impedance value RM. For example, the second test unit 202 detects the impedance of each metal line M of the battery piece to the right of the third drawing, and obtains the second impedance value RM of all the metal lines.

Step S210: The comparing unit 203 compares the first impedance value RS with the second impedance value RM to generate a comparison result O. In one embodiment, the comparison result O may be a difference between the first impedance value RS and the second impedance value RM, such as RS-RM.

Step S212: The determining unit 204 receives the comparison result O, and determines whether the comparison result O is greater than or equal to a preset value a. When the comparison result O is greater than or equal to the preset value a, it is determined that any two bus bars BS1 and BS2 include a pre-between Set more than the number of broken lines. For example, when the metal line in FIG. 3 is not broken, RS is equal to 3.3 milliohms (mohm), and RM is equal to 50 milliohms (mohm). When any two bus bars BS1 and BS2 are disconnected as shown in FIG. 3 When disconnected, RS is equal to 3.3 milliohms (mohm) and RM is equal to 60 milliohms (mohm). At this time, it is known that there may be disconnection between any two bus bars BS1 and BS2 by using the difference in resistance.

The disconnection judgment formula of an embodiment may be:

It indicates that the number of normal or disconnected lines between any two bus bars BS1 and BS2 is less than a preset number.

It indicates that any two bus bars BS1 and BS2 are not normal, and the number of disconnected wires is greater than a preset number.

It should be noted that the preset value a has a positive correlation with the preset number of disconnections. Furthermore, the setting of the preset value a is set according to the designer's needs. For example, if the number of disconnected wires of one battery piece must be less than 5, the battery piece having 5 or more broken wires must be screened out. .

Figure 4 shows a first impedance value (series resistance) and a portion of an embodiment of the present invention. A look-up table consisting of two impedance values (metal wire resistance). In the figure, the horizontal axis represents the second impedance value RM, and the vertical axis represents the first impedance value RS. Wherein, each point constituting the oblique line B is measured by a plurality of battery pieces which are completely unbroken or whose number of broken lines is less than a value. The oblique line B can be used as a comparison reference. When the RM and RS detected by a battery chip correspond to a point higher than the oblique line C - that is, the preset value a is exceeded, the disconnection of the battery piece can be determined. The number exceeds the standard. For example, when the corresponding point falls in the broken line exceeding the standard area of the thick black line, such as the point P1, the number of the battery segment lines exceeds the standard.

It should be noted that the number of broken lines above the ratio is defined as the number of broken lines exceeding the standard. According to the demand setting, for example, if there is 80 lines in a battery, the five lines are cut obliquely B and the broken 10 is oblique line C. The broken line exceeding the standard area of the triangle is set at a ratio of the number of broken lines to the number of buses of 10/80 or more. , defined as the battery segment line does not meet the specifications. Furthermore, the data presented in the embodiments of the present invention are merely examples, and the present invention is not limited to the above data, and can be arbitrarily designed according to requirements.

The method and device for detecting a battery piece according to an embodiment of the present invention, using the detection series electric Resistance to metal line resistance, and comparison can detect whether the degree of disconnection of all or part of a cell is in conformity with specifications. The detection of the degree of disconnection can, for example, determine the degree of disconnection represented by the shadow of the EL shaded block.

The present invention has been described above by way of examples, and the scope of the invention is not limited thereto, and various modifications and changes may be made without departing from the scope of the invention.

Claims (8)

A battery chip detecting method includes: providing a battery piece, the battery piece includes a plurality of bus bars, and any two of the bus bars include a plurality of metal wires; when measuring the efficiency of the battery chip, the solar light simulator is used A first impedance value is obtained; a detecting step of detecting an impedance of the plurality of metal lines between the two bus bars to obtain a second impedance value of the total impedance of the plurality of metal lines; comparing the first impedance value And the second impedance value, a comparison result is generated; and when the comparison result is greater than or equal to a preset value, determining that the two bus bars of the detecting step comprise a predetermined number or more of disconnected lines. The method of claim 1, wherein the first impedance value is a series resistance of the operating condition of the battery. The method of claim 1, wherein the preset value has a positive correlation with the predetermined number of broken lines. The method of claim 1, wherein the comparison result is a difference between the first impedance value and the second impedance value. A battery test device includes: a first test unit for detecting a series resistance of the operation of the battery to detect a first impedance value; and a second test unit for detecting any two bus bars An impedance of the plurality of metal lines to obtain a second impedance value of the total impedance of the plurality of metal lines; and a comparing unit for comparing the first impedance value with the second impedance value to generate a comparison result; a judging unit, when the comparison result is greater than or equal to a preset value, determining that the two bus bars comprise a predetermined number or more of disconnected lines. The device of claim 5, wherein the preset value has a positive correlation with the predetermined number of broken lines. The device of claim 5, wherein the comparison result is a difference between the first impedance value and the second impedance value. A method for detecting a battery piece, comprising: providing a plurality of battery pieces having no broken wires or having a number of broken wires smaller than a predetermined value, each of the battery sheets including a plurality of bus bars, and any two of the bus bars include a plurality of bus bars a metal line; detecting a series resistance of each of the battery operating conditions to obtain a first impedance value; detecting an impedance of the plurality of metal lines between the two bus bars of each of the battery sheets to obtain the impedance of the plurality of metal lines Combining a second impedance value; defining a current excess area according to the first resistance value and the second resistance value obtained by each of the battery sheets; and measuring the first resistance value of the battery piece to be tested and the first The second resistance value is used to describe whether the first resistance value and the second resistance value of the battery to be tested fall within the broken line exceeding the standard area to determine whether the disconnection of the battery piece to be tested exceeds a standard.