CN212380431U

CN212380431U - Battery pack composing structure

Info

Publication number: CN212380431U
Application number: CN202021096155.7U
Authority: CN
Inventors: 陈道远; 周志发; 刘玲玲
Original assignee: Shanghai Ja Solar Pv Technology Co ltd
Current assignee: Shanghai Ja Solar Pv Technology Co ltd
Priority date: 2020-06-15
Filing date: 2020-06-15
Publication date: 2021-01-19
Anticipated expiration: 2030-06-15

Abstract

The utility model discloses a battery pack composing structure, battery unit and bypass diode including parallel connection, battery unit includes that mirror symmetry locates the first group cluster and the second group cluster of bypass diode both sides, first group cluster with the second group cluster parallel connection, just first group cluster with the second group cluster is established ties by a plurality of 1/N section batteries and is formed, and wherein, N is more than or equal to 3's positive integer. The utility model provides a battery pack composing structure, its inside current loss is low, and the dc-to-ac converter selects for use the scope wide, and the subassembly production technology composing degree of difficulty is little.

Description

Battery pack composing structure

Technical Field

The utility model relates to the field of photovoltaic technology, especially, relate to a battery pack composing structure.

Background

With the increasing demand for high power cell modules in the field of photovoltaic technology, the power of the cell modules has been developed at least to 500W. In the development of technology for increasing the power of battery modules, increasing the size of battery pieces is the simplest way, and currently, large-size battery pieces of 210mm × 210mm are produced in the field of photovoltaic technology. After the size of the battery piece is increased, technicians adopt a half slicing mode or a third slicing mode due to the fact that the internal current loss of the battery piece is increased.

By taking a cell piece of 210mm × 210mm as an example, a half-cut cell piece of a large size is arranged in a manner that a long side of the half-cut cell piece is parallel to a short side of a photovoltaic glass as shown in fig. 1 and fig. 2, every 20 (2 columns and 10 rows) half-cut cells are connected in series to form a first group of strings 3, the current of the first group of strings 3 is 8.75A, the first group of strings 3 and a second group of strings 4 symmetrical to the first group of strings 3 about a bypass diode form a cell unit 1, and the output current of the cell unit 1 is 17.5A. The current loss of each string is high, resulting in low output power of the battery assembly. In addition, the output current of the battery unit is large, an inverter matched with the battery unit is not available in the field, and even if a small amount of inverters can be matched with the battery unit, the disadvantage of peak current limiting is caused. In addition, the problem of odd-numbered rows of half-sliced cells when the half-sliced cells are arranged on the photovoltaic glass is limited by the existing setting standard of the width of the photovoltaic glass, and the situation that the half-sliced cells in a single row are connected in series to form a single string 9 can occur according to the mode that every two rows are connected in series to form a group of strings, and at the moment, a jumper wire 8 is needed to be used as a lead-out wire of a bypass diode in a junction box, so that the production difficulty of a cell assembly is greatly increased.

One-third slicing mode as shown in fig. 3 and 4, the arrangement structure can reduce the current of the first group of strings 3 to below 6A by arranging the long sides of the one-third sliced cells in parallel with the short sides of the photovoltaic glass. However, in order to satisfy the requirement of high power of the battery pack above 500W, the number of the first group of strings 3 needs to be increased by one third, that is, the first group of strings 3 needs 30 (2 columns and 15 rows) one third of sliced cells to be connected in series. However, one third of the sliced cells used in the first series 3 are large in number, and when the hot spot effect occurs, the reverse bias voltage applied to the cells is too high, and the hot spot temperature exceeds 180 ℃, so that the cell components are easily burnt. Moreover, a situation that single-row battery pieces are connected in series to form a single-row battery string 9 in a half-slicing mode also occurs, a jumper wire 8 is needed to be used as a lead-out wire of a bypass diode in a junction box, and the difficulty of production of the battery assembly is increased.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to overcome prior art defect to a battery pack composing structure is provided, this battery pack composing structure inside current loss is low, the dc-to-ac converter is chooseed for use the wide range, the battery pack production technology composing degree of difficulty is little.

In order to achieve the above object, the present invention provides the following technical solutions:

the utility model provides a battery pack composing structure, includes parallel connection's battery unit and bypass diode, the battery unit includes that mirror symmetry locates the first group cluster and the second group cluster of bypass diode both sides, first group cluster with the second group cluster parallel connection, just first group cluster with the second group cluster is established ties by a plurality of 1/N section batteries and is formed, and wherein, N is more than or equal to 3 positive integer.

In one embodiment, the array of 1/N-slice cells is arranged on the photovoltaic glass, and the long side of each 1/N-slice cell is parallel to the long side of the photovoltaic glass.

In one embodiment, each of the 1/N-slice cells in the first or second set of strings is connected in series by an interconnection bar.

In one embodiment, the interconnection bar is any one of a solder ribbon or a conductive paste.

In one embodiment, there are at least three battery units, each of the battery units is connected in series in sequence, and each of the battery units is connected in parallel with one of the bypass diodes.

In one embodiment, the 1/N sliced cells are 1/3 sliced cells, and the number of 1/3 sliced cells in the first or second series of strings does not exceed 26.

In one embodiment, the bypass diode is internally disposed in a junction box disposed on the backsheet glass or photovoltaic backsheet.

Compared with the prior art, the utility model provides a pair of battery pack composing structure has following beneficial effect:

the utility model provides a battery pack composing structure, the long limit of each 1/N section battery all is on a parallel with photovoltaic glass's long limit. Compared with the prior art, the internal current loss of each string is reduced, and the output power of the battery assembly is ensured; the optional inverter is matched with the inverter for use, so that the adverse situation of peak current limiting is avoided; when the hot spot effect occurs, because the number of the arranged sliced batteries is not more than 26, the reverse bias voltage of the battery plates is reduced when the hot spot effect occurs, so that the hot spot risk is reduced; the battery pack typesetting structure does not need to use jumper wires, is convenient for typesetting the battery pack production process, reduces the production difficulty of the battery pack, and improves the production efficiency of the battery pack.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a schematic circuit diagram of a prior art one-half slice assembly for a 210mm battery;

FIG. 2 is a schematic diagram of a layout structure of a half slice assembly of a 210mm battery in the prior art;

FIG. 3 is a schematic circuit diagram of a one-third slicing assembly for a 210mm battery according to the prior art;

FIG. 4 is a schematic diagram of a layout structure of one-third slice assemblies of a 210mm battery in the prior art;

fig. 5 is a schematic circuit diagram of a one-third slicing assembly for a 210mm battery according to an embodiment of the present invention;

fig. 6 is a schematic diagram of a typesetting structure of a one-third slice assembly of a 210mm battery according to an embodiment of the present invention.

Description of reference numerals:

1. a battery cell; 2. a bypass diode; 3. a first set of strings; 4. a second set of strings; 5. 1/N sliced cell; 6. photovoltaic glass; 7. a junction box; 8. a jumper wire; 9. a single string.

Detailed Description

The technical solution of the present invention will be described clearly and completely with reference to the accompanying drawings, and obviously, the described embodiments are some, but not all embodiments of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplification of description, but do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present invention, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood in specific cases to those skilled in the art.

Furthermore, the technical features mentioned in the different embodiments of the invention described below can be combined with each other as long as they do not conflict with each other.

Examples

As shown in fig. 5 and fig. 6, the utility model provides a battery pack composing structure, including battery unit 1 and bypass diode 2, bypass diode 2 sets up in the inside of terminal box 7, and terminal box 7 sets up at battery pack's back usually, and commonly used backplate glass, photovoltaic backplate in the photovoltaic field are adopted at battery pack's the back. That is, when the battery assembly is a single glass assembly, the back surface of the battery assembly is a photovoltaic back plate, and the junction box 7 is arranged on the photovoltaic back plate; when the battery assembly is a dual-glass assembly, the back surface of the battery assembly is back plate glass, and the junction box 7 is arranged on the back plate glass. The battery unit 1 includes a first group of strings 3 and a second group of strings 4, the first group of strings 3 and the second group of strings 4 being symmetrically disposed about the bypass diode 2 and being respectively connected in parallel with the bypass diode 2. The first and second series of

strings

3 and 4 each comprise a plurality of 1/N sliced cells 5 connected in series, i.e. a whole cell is cut into N sliced cells by means of laser or the like, each sliced cell is called a 1/N sliced cell, where N is a positive integer. With the gradual increase of the size of the cell in the photovoltaic field, the typesetting structure of the cell assembly can be suitable for 1/4 slicing, 1/5 slicing and the like of other large-size cells.

Taking the first group of strings 3 as an example, the first group of strings 3 comprises 16 1/3 sliced cells, and each 1/3 sliced cell is arranged in an array in a way that the long edge of each sliced cell is parallel to the long edge of the photovoltaic glass 6. In the embodiment, the number of columns of the sliced cells is calculated in parallel with the long side direction of the photovoltaic glass 6, and the number of rows of the sliced cells is calculated in parallel with the short side direction of the photovoltaic glass 6, then 16 1/3 sliced cells are arranged on the photovoltaic glass 6 in the form of 2 rows and 8 columns, the 1/3 sliced cells are connected with the photovoltaic glass 6 through the packaging adhesive film, and the 1/3 sliced cells are connected in series through the interconnecting strips with conductive performance, which can be solder strips or conductive adhesive and the like. Accordingly, the second set of strings 4 is arranged mirrored on the symmetrical side with respect to the bypass diode 2.

After the battery piece is cut into 1/3 sliced batteries, the internal current of the strings of the first string 3 or the second string 4 is reduced to 5.85A, and the internal current loss of each string is reduced, so that the output power of the battery assembly is ensured. The output current of the battery unit 1 is about 11.7A, and an optional inverter is matched with the battery unit in the photovoltaic field, so that the adverse situation of peak current limiting is avoided.

The 1/3 sliced batteries in the first group of strings 3 are not more than 26, and the voltage of the sliced batteries is not higher because the number of the sliced batteries is not large. If the first group string 3 generates the hot spot effect due to the shielding or the defects of the battery pieces, and the like, because the number of the 1/3 sliced batteries is not more than 26, the reverse bias voltage of the battery pieces during the hot spot effect is reduced, and the hot spot temperature is controlled to be about 160 ℃, so that the hot spot risk is reduced.

The number of the battery units 1 arranged on the photovoltaic glass 6 exceeds 3, the number of the battery units is the same as that of the corresponding bypass diodes 2, the battery units 1 are sequentially connected in series, and each battery unit 1 is connected with one bypass diode 2 in parallel. As shown in fig. 5 and 6, 5 battery units 1 are arranged on the photovoltaic glass 6, and the number of the circuit forms formed by the first group of strings 3 and the second group of strings 4 is 5, i.e. the number of the circuit forms can be enlarged to 4, 5, 6, etc. relative to the prior art, so that the output power of the battery assembly is ensured. The battery pack typesetting structure does not need to use a jumper wire 8 (as shown in figures 1 to 4), so that the battery pack production process typesetting is facilitated, the production difficulty of the battery pack is reduced, and the production efficiency of the battery pack is improved.

When the 1/2 slice and 1/3 slice of the 210mm cell are applied to a single-glass assembly or a double-sided double-glass assembly, the output current of the cell is shown in table 1:

TABLE 1

Component type	1/2 slicing	1/3 slicing
			Single glass assembly	17.5A	11.7A
Double-glass double-sided assembly	22.8A	15.2A

When the 1/2 slice and 1/3 slice of the 185mm battery piece are applied to a single-glass assembly or a double-sided double-glass assembly, the output current of the battery unit is shown in table 2:

TABLE 2

Component type	1/2 slicing	1/3 slicing
			Single glass assembly	13.6A	9.1A
Double-glass double-sided assembly	17.7A	11.8A

When the 1/2 section and 1/3 section of the 180mm cell sheet are applied to a single-glass assembly or a double-sided double-glass assembly, the output current of the cell is shown in table 2:

TABLE 3

Component type	1/2 slicing	1/3 slicing
			Single glass assembly	12.9A	8.6A
Double-glass double-sided assembly	16.7A	11.1A

As can be seen from tables 1 to 3, the battery layout structure using the 1/3 sliced battery effectively reduces the output current of the battery cells of the single-glass assembly and the double-glass double-sided assembly, thereby reducing the risk of hot spots caused by current rise and reducing the circuit loss.

The above description is only for the specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention should be covered by the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. The utility model provides a battery pack composing structure, its characterized in that, includes parallel connection's battery unit (1) and bypass diode (2), battery unit (1) includes that mirror symmetry locates first group cluster (3) and second group cluster (4) of bypass diode (2) both sides, first group cluster (3) with second group cluster (4) parallel connection, just first group cluster (3) with second group cluster (4) are established ties by a plurality of 1/N sliced battery (5) and are formed, and wherein, N is more than or equal to 3 positive integer.

2. The cell assembly layout structure according to claim 1, wherein the array of 1/N sliced cells (5) is arranged on a photovoltaic glass (6), and the long side of each 1/N sliced cell (5) is parallel to the long side of the photovoltaic glass (6).

3. The battery pack layout structure according to claim 1, wherein each of the 1/N-slice batteries (5) in the first group of strings (3) or the second group of strings (4) is connected in series by an interconnection bar.

4. The battery pack layout structure of claim 3, wherein the interconnection bars are any one of solder strips or conductive paste.

5. The battery pack layout structure according to claim 1, wherein there are at least three battery units (1), each battery unit is connected in series in turn, and each battery unit is connected in parallel with one bypass diode.

6. The battery pack layout structure according to claim 1, wherein the 1/N sliced batteries (5) are 1/3 sliced batteries, and the number of the 1/3 sliced batteries in the first group of strings (3) or the second group of strings (4) is not more than 26.

7. The battery pack layout structure according to claim 1, wherein the bypass diode (2) is internally disposed in a junction box (7), and the junction box (7) is disposed on a backplane glass or a photovoltaic backplane.