CN212542456U

CN212542456U - Battery pack

Info

Publication number: CN212542456U
Application number: CN202021314579.6U
Authority: CN
Inventors: 靳玉鹏; 李华
Original assignee: Taizhou Lerri Solar Technology Co Ltd
Current assignee: Taizhou Longi Solar Technology Co Ltd
Priority date: 2020-07-07
Filing date: 2020-07-07
Publication date: 2021-02-12
Anticipated expiration: 2030-07-07

Abstract

The utility model provides a battery pack relates to the photovoltaic technology field. The battery pack includes: at least two solar cells, a conductive interconnect; the solar cell comprises a silicon wafer, a doping layer, a positive electrode and a negative electrode; the silicon chip comprises at least two power generation regions and an open region positioned between the adjacent power generation regions; the doping layer is formed on a backlight surface of the power generation region in the silicon wafer and is disconnected at a position corresponding to the open region; the anode is formed on the backlight surface of the p-type doped region; the cathode is formed on the backlight surface of the n-type doped region; the conductive interconnection piece is electrically connected with the anode of one solar cell and the cathode of the adjacent solar cell, and is simultaneously connected with each sub-cell unit in the solar cell in series. Each sub-battery unit in the solar battery does not need to be connected in series in advance, the process is simple, and the production efficiency is improved. Each sub-cell unit inside the solar cell is not physically divided, and the fragmentation rate is reduced.

Description

Battery pack

Technical Field

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

Background

The battery component can reduce the power loss by connecting a plurality of solar batteries in series, thereby having wide application prospect.

At present, a solar cell is generally divided into pieces, and then the divided cells are connected in series, so that on one hand, the problem of poor passivation performance of the cell module exists, and on the other hand, the divided cells are not easy to align accurately in the series connection process.

SUMMERY OF THE UTILITY MODEL

The utility model provides a battery pack aims at solving the problem that current battery pack passivation performance is poor, difficult accurate counterpoint.

According to the utility model discloses an aspect provides a battery pack, battery pack includes: at least two solar cells, a conductive interconnect;

the solar cell comprises a silicon wafer, a doping layer, a positive electrode and a negative electrode;

the silicon chip comprises at least two power generation regions and an open region positioned between the adjacent power generation regions;

the doping layer is formed on a backlight surface of a power generation region in the silicon wafer and is disconnected at a position corresponding to the open region; the doping layer comprises a p-type doping region and an n-type doping region which are opposite in doping type;

the anode is formed on a backlight surface of the p-type doped region;

the negative electrode is formed on a backlight surface of the n-type doped region;

the solar cell is divided into at least two sub-cell units through the open area, and each sub-cell unit is a part of the solar cell corresponding to one power generation area;

the conductive interconnection piece is conductively connected with the anode of one solar cell and the cathode of the adjacent solar cell so as to serially connect the adjacent solar cells, and the conductive interconnection piece is simultaneously serially connected with each sub-cell unit in the solar cell.

Optionally, the conductive interconnection is a conductive wire.

Optionally, the conductive interconnection is a conductive line in a conductive backplane.

Optionally, the dimension of the conductive line is 0.01-0.8mm in a direction perpendicular to the length direction of the conductive line.

Optionally, the width of the open area is 500-.

Optionally, in a case that the volume resistivity of the open area is less than or equal to 1ohm "cm, the width of the open area is 2000-;

the width of the open area is 500-2000um in the case where the volume resistivity of the open area is greater than or equal to 3ohm "cm.

Optionally, when the conductive interconnection is a conductive wire, a connection line between a positive electrode of one sub-battery unit and a negative electrode of an adjacent sub-battery unit in one solar battery is parallel to one edge of the solar battery.

Optionally, the solar cell further includes: and the isolation region is positioned between the p-type doped region and the n-type doped region in the power generation region, and the width of the isolation region is 0.1-100 um.

Optionally, the solar cell further includes: the third doped region is positioned on the light facing surface of the power generation region of the silicon wafer; and the third doped region is disconnected at the position corresponding to the empty opening region.

Optionally, the solar cell further includes: a passivation tunneling layer located between the silicon wafer and the doping layer;

the passivation tunneling layer covers the open area.

Optionally, in the same subcell, the p-type doped region is composed of a plurality of p-type doped sub-regions communicated with each other, and the n-type doped region is composed of a plurality of discrete n-type doped sub-regions;

or, in the same subcell, the n-type doped region is composed of a plurality of interconnected n-type doped sub-regions, and the p-type doped region is composed of a plurality of discrete p-type doped sub-regions.

Optionally, the solar cell further includes: the front passivation layer is positioned on the light facing surface of the silicon wafer;

and/or a back passivation layer positioned between the silicon chip and the positive electrode and the negative electrode;

the front passivation layer and the back passivation layer cover the open region.

Optionally, each of the open regions is distributed in parallel at intervals along one side of the solar cell, and the open regions extend from one end of the solar cell to the other end of the solar cell.

Optionally, the solar cell further includes: the edges at both sides are connected with electrodes, and the both sides are along the arrangement direction of each sub-battery unit.

Optionally, the edge connection electrode is in the form of a continuous strip or a discrete dot.

Optionally, the p-type doped region and the n-type doped region are both in a shape like a Chinese character feng, and the shape like the Chinese character feng is divided into a vertical region and a penetrating region; the penetrating area is parallel to the arrangement direction of each sub-battery unit;

the anode and the cathode are in a shape like Chinese character feng;

the positive electrode consists of a first contact electrode and a first connecting electrode, the first connecting electrode is arranged on a penetrating region of the p-type doped region, and the first contact electrode is arranged on a vertical region of the p-type doped region;

the negative electrode consists of a second contact electrode and a second connecting electrode, the second connecting electrode is arranged on a penetrating region of the n-type doped region, and the second contact electrode is arranged on a vertical region of the n-type doped region;

the conductive interconnection conductively connects the first connection electrode of one sub-cell unit and the second connection electrode of an adjacent sub-cell unit to connect the adjacent sub-cell units in series.

Optionally, the battery assembly further includes: a supplemental electrode; the supplemental electrodes are conductively connected to at least two of a set of conductive interconnects; the group of conductive interconnections are each conductive interconnection for series connection of two adjacent sub-battery cells in one solar battery, or each conductive interconnection for series connection of two adjacent solar batteries.

The utility model discloses in the embodiment, among the solar cell in the subassembly: the silicon wafer comprises at least two power generation regions, an open region positioned between the adjacent power generation regions, a p-type doped region and an n-type doped region with opposite doping types, and a backlight surface formed in the power generation regions in the silicon wafer, wherein the doped layer formed by the p-type doped region and the n-type doped region is disconnected in the open region, and further, compared with the p-type doped region and the n-type doped region, the backlight surface of the open region exists as a high-resistance body or an insulator, namely, the backlight surface of the whole silicon wafer is electrically divided into at least two parts instead of physical division through the backlight surface positioned in the open region. Meanwhile, the anode is formed on the backlight surface of the p-type doped region, the cathode is formed on the backlight surface of the n-type doped region, the solar cell is electrically divided into at least two sub-cell units through the open region in the silicon wafer instead of being physically divided, and each sub-cell unit is a part of the solar cell corresponding to one power generation region. Each sub-battery unit in one solar battery is still positioned on the whole silicon chip, and the sub-battery units in one solar battery are not physically divided but electrically divided, so that the efficiency loss caused by the combination of stress damage and thermal damage caused by cutting is avoided, and the efficiency loss caused by the passivation loss of the physically divided section is also avoided. Each sub-battery unit in one solar battery does not need to be connected in series in advance, and each solar battery and each sub-battery unit in each solar battery are connected in series by adopting the conductive interconnection piece in the process of forming the assembly, so that the process is simple, and the production efficiency is improved. Moreover, each sub-battery unit in one solar battery is not physically divided, and is also a physical whole, so that the yield reduction risk caused by internal interconnection is reduced, and the fragment rate is reduced.

According to a second aspect of the present invention, there is provided a method for producing a battery module, comprising the steps of:

providing a solar cell; the solar cell comprises a silicon wafer, a doping layer, a positive electrode and a negative electrode; the silicon chip comprises at least two power generation regions and an open region positioned between the adjacent power generation regions; the doping layer is formed on a backlight surface of a power generation region in the silicon wafer and is disconnected at a position corresponding to the open region; the doping layer comprises a p-type doping region and an n-type doping region which are opposite in doping type; the anode is formed on a backlight surface of the p-type doped region; the negative electrode is formed on a backlight surface of the n-type doped region;

providing a conductive interconnect;

connecting the positive electrode of one solar cell and the negative electrode of the adjacent solar cell in a conductive way by using the conductive interconnection piece so as to connect the adjacent solar cells in series;

and simultaneously connecting the sub-battery units in the solar battery in series by using the conductive interconnection piece.

Optionally, in the case that the conductive interconnection is a conductive wire, the step of providing a conductive interconnection includes:

coating a conductive adhesive material on the conductive wire;

the step of conductively connecting includes:

electrically connecting the positive electrode of one solar cell and the negative electrode of the adjacent solar cell at 80-350 ℃ by using an electric wire coated with an electrically conductive bonding material so as to serially connect the adjacent solar cells;

and connecting the sub-battery units in the solar battery in series at 80-350 ℃ by using a conductive wire coated with a conductive bonding material.

In the embodiment of the present invention, the production method of the battery pack has the same or similar advantageous effects as those of the battery pack.

Drawings

In order to more clearly illustrate the technical solution of the embodiments of the present invention, the drawings required to be used in the description of the embodiments of the present invention will be briefly introduced below, and 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 these drawings without inventive labor.

Fig. 1 shows a schematic structural diagram of a first solar cell string according to an embodiment of the present invention;

fig. 2 shows a schematic structural diagram of a first solar cell according to an embodiment of the present invention;

fig. 3 shows a schematic structural diagram of a second solar cell string according to an embodiment of the present invention;

fig. 4 shows a schematic structural diagram of a second solar cell in an embodiment of the present invention;

fig. 5 shows a schematic structural diagram of a third solar cell according to an embodiment of the present invention;

fig. 6 shows a schematic structural diagram of a fourth solar cell in an embodiment of the present invention;

fig. 7 shows a schematic structural diagram of a fifth solar cell according to an embodiment of the present invention;

fig. 8 shows a schematic structural diagram of a sixth solar cell according to an embodiment of the present invention;

fig. 9 shows a schematic structural diagram of a seventh solar cell according to an embodiment of the present invention;

fig. 10 shows a schematic structural diagram of an eighth solar cell according to an embodiment of the present invention;

fig. 11 shows a schematic structural diagram of a ninth solar cell according to an embodiment of the present invention;

fig. 12 shows a schematic structural view of a first solar cell with conductive interconnects in an embodiment of the invention;

fig. 13 shows a schematic enlarged view of a portion of a solar cell with conductive interconnects in an embodiment of the invention.

Description of the figure numbering:

1-silicon wafer, 11-open region, 2-p-type doped region, vertical region of 21-p-type doped region, through-region of 22-p-type doped region, 23-p-type doped sub-region, 3-n-type doped region, vertical region of 31-n-type doped region, through-region of 32-n-type doped region, 33-n-type doped sub-region, 4-solar cell, 5-anode, 51-first contact electrode, 52-first connection electrode, 6-cathode, 61-second contact electrode, 62-second connection electrode, 7-front passivation layer, 8-back passivation layer, 9-supplemental electrode, 10-edge connection electrode, 12-third doped region, 13-isolation region, 14-passivated tunneling layer, 15-semiconductor region, 16-conductive interconnection.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that 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.

The inventor of the application researches and discovers that the reason that the passivation performance of the existing battery pack is poor is as follows: the current battery module is generally that the solar battery is physically cut into a plurality of pieces by physical cutting, and the plurality of pieces are connected in series. But this can cause severe efficiency loss for the solar cell due to loss of passivation of the cut surfaces. At the same time, cutting damage and thermal damage from cutting can result in efficiency losses. In addition, the solar cell is physically cut into a plurality of cells to obtain a plurality of cells, and each cell which is independent from each other needs to be accurately aligned in the interconnection process of the module, so that the process is complex, fragments are easily caused, and the yield is easily reduced.

In the embodiment of the present invention, referring to fig. 1, fig. 1 shows a schematic structural diagram of a first solar cell string in the embodiment of the present invention. Fig. 1 may be a bottom view looking from the backlight face to the light-facing face of the solar cell string. The solar cell string shown in fig. 1 is laminated with a cover plate and a front encapsulant on the light-facing side, a back encapsulant on the back side, and a back sheet to form a cell module. The cell assembly includes at least two solar cells, and an electrically conductive interconnect 16. The solar cell is a back contact solar cell. Regarding apron, preceding encapsulating material, back encapsulating material and backplate can be selected according to actual need, the embodiment of the utility model provides a do not do specifically to this and restrict.

The conductive interconnection 16 may be a conductive back plate or a conductive wire, and is not particularly limited in the embodiment of the present invention.

In the embodiment of the present invention, referring to fig. 2, fig. 2 shows a schematic structural diagram of a first solar cell in the embodiment of the present invention. The solar cell includes: a silicon wafer 1, the silicon wafer 1 comprising at least two power generation regions, and an open region 11 located between adjacent power generation regions. As shown in fig. 2, the silicon wafer 1 includes 2 power generation regions, which are respectively a portion located on the left side of the left dotted line in the silicon wafer 1, a portion located on the right side of the right dotted line in the silicon wafer 1, and 1 open region 11, specifically, a portion located between 2 dotted lines in the silicon wafer 1.

The number of power generation regions and the number of open regions included in the silicon wafer may be set as needed.

The solar cell further includes: and a doping layer formed on the backlight surface of the power generation region in the silicon wafer 1, wherein the doping layer comprises a p-type doping region 2 and an n-type doping region 3 with opposite doping types, and is formed on the backlight surface of the power generation region in the silicon wafer 1. The doped layer is disconnected at the position corresponding to the open region 11, that is, the doped layer is not covered or diffused at the position corresponding to the open region 11, and the backlight surface of the open region 11 exists as a high resistance body or an insulator, so that the backlight surface of the whole silicon wafer 1 is electrically divided into at least two parts, not physically divided.

It should be noted that the whole silicon wafer 1 is a uniform whole, that is, the doping concentration and the doping type of the open area 11 of the silicon wafer 1 are correspondingly the same as the doping concentration and the doping type of the power generation area in the silicon wafer 1, so that the power generation area and the open area do not need to be distinguished in the process of manufacturing the silicon wafer 1, and the process is simple. The doping concentration of the open region 11 is less than that of the p-type doping region 2 and less than that of the n-type doping region 3. The doping type of the open area 11 is the same as or different from the doping type of the p-type doped region 2. The doping type of the open area 11 is the same as or different from the doping type of the n-type doped region 3. In the embodiment of the present invention, this is not particularly limited.

For example, the open region 11 may be doped p-type and the doping concentration may be 10¹⁶cm^-3The doping concentration of the p-type doped region 2 may be 10²⁰-10²¹cm^-3On the left and right, the doping concentration of the n-type doped region 3 may be 10²⁰-10²¹cm^-3Left and right.

And the positive electrode 5 is formed on the backlight surface of the p-type doped region 2, and the positive electrode 5 is also arranged corresponding to the power generation region because the p-type doped region 2 is formed on the backlight surface of the power generation region in the silicon wafer 1. That is, the positive electrode 5 is not provided at a position corresponding to the open region 11, and the positive electrode 5 mainly collects carriers corresponding to the power generation region.

And a negative electrode 6 formed on the back surface of the n-type doped region 3, wherein the negative electrode 6 is also provided corresponding to the power generation region since the n-type doped region 3 is formed on the back surface of the power generation region in the silicon wafer 1. That is, the negative electrode 6 is not provided at a position corresponding to the open region 11, and the negative electrode 6 collects carriers corresponding to the power generation region.

Note that the material of the positive electrode 5 and the material of the negative electrode 6 are the same or different, and the embodiment of the present invention is not particularly limited. In the case where the materials of the positive electrode 5 and the negative electrode 6 are the same, the process is simple.

For example, the positive electrode 5 shown in fig. 2 may be a silver electrode, and the negative electrode 6 may be distributed using aluminum grid lines. The silicon chip 1 can be a p-type silicon chip, and has mature and simple process and lower cost.

The positive electrode 5 and the negative electrode 6 are insulated from each other with an insulating gap therebetween. The size of the insulation gap between positive electrode 5 and negative electrode 6 is not particularly limited herein.

The solar cell is divided into at least two sub-cell units by the open region, and each sub-cell unit is a part of the solar cell corresponding to one power generation region. For example, referring to fig. 2, the solar cell is divided into 2 sub-cells by the open region 11, and the sub-cells are a portion of the solar cell corresponding to the left power generation region of the left dotted line and a portion of the solar cell corresponding to the right power generation region of the right dotted line. The 2 sub-battery units in the solar battery are not physically divided, but are electrically divided, so that the efficiency loss caused by the combination of stress damage and thermal damage caused by cutting is avoided, and the efficiency loss caused by the passivation loss of the physically divided cross section is also avoided. On the other hand, each sub-battery unit comprises an independent power generation structure, and the sub-battery units in one solar battery are connected in series, so that the output voltage of the solar battery is the sum of the sub-battery units, and the output current is reduced to the current value of a single sub-battery unit, so that the internal resistance loss of the solar battery is reduced, the output power is improved, and the battery efficiency is improved.

The conductive interconnection piece is conductively connected with the anode of one solar cell and the cathode of the adjacent solar cell so as to serially connect the adjacent solar cells, the conductive interconnection piece is serially connected with each sub-cell unit in the solar cell at the same time, and because each sub-cell unit in one solar cell is not physically divided and is also physically integral, the internal serial connection process is simple in contraposition process, the yield reduction risk caused by more interconnection process is reduced, and the fragment rate is reduced. Each sub-battery unit in one solar battery does not need to be connected in series in advance, and each solar battery and each sub-battery unit in each solar battery are connected in series by adopting the conductive interconnection piece in the process of forming the assembly, so that the process is simple, and the production efficiency is improved.

For example, referring to fig. 1, the battery module includes two solar cells 4, and each solar cell 4 is divided into 4 sub-battery units. Shown in fig. 1 as a dashed box is a solar cell 4. The conductive interconnection 16 located in the middle of the 2 solar cells 4 is conductively connected to the rightmost anode 5 of the rightmost subcell of the left solar cell 4 and to the leftmost cathode 6 of the leftmost subcell of the right solar cell, thereby conductively interconnecting the left solar cell 4 and the right solar cell 4. Meanwhile, the conductive interconnection 16 conductively connects the positive electrode 5 of one sub-cell unit and the negative electrode 6 of an adjacent sub-cell unit, both located in the solar cell 4, to connect the positive electrode of one sub-cell unit and the adjacent sub-cell unit, both located in the solar cell 4, in series.

Alternatively, the conductive interconnection is one of a straight line, a broken line, or a wavy line, and thus the form of the conductive interconnection is various. For example, referring to fig. 1 or 2, the conductive interconnects are straight lines.

Optionally, when the conductive interconnection piece is a conductive wire, the size of the conductive wire is 0.01-0.8mm in the direction perpendicular to the length direction of the conductive wire, that is, the thickness of the conductive wire is 0.01-0.8mm, and the conductive interconnection piece with the size has a good conductive interconnection effect and low cost. The length direction of the conductive wires is parallel to the arrangement direction of the sub-battery units.

Optionally, in the battery module, the more the number of the sub-battery units included in the solar battery is, the thinner the conductive wire is, so that the conductive interconnection effect is good, and the cost is low. Since the greater the number of sub-cells included in the solar cell, the smaller the current shared in each conductive line, and the thinner the conductive line can be.

For example, in a battery module, if one solar cell includes 8 subcells, the diameter of the conductive wire may be 0.02-0.2 mm. In the battery module, if one solar cell includes 3 sub-cells, the diameter of the conductive wire may be 0.05-0.8 mm.

Meanwhile, the diameter of the conductive wire and the widths of the p-type doped region and the n-type doped region of the solar cell are also related. It should be noted that, when the same conductive wire is used for transmitting current in a larger area, the diameter of the conductive wire needs to be increased.

Optionally, the conductive interconnection piece may be a conductive circuit in the conductive back plate, so that when the conductive back plate realizes series connection between the batteries, synchronous series connection of the sub-battery units in each battery can also be realized.

Optionally, referring to fig. 2, the width w1 of the open area 11 is 500-.

Optionally, the width of the open area may be inversely proportional to the volume resistivity of the open area, that is, the larger the volume resistivity of the open area is, the smaller the width of the open area is, the smaller the volume resistivity of the open area is, and the larger the width of the open area is, which is not only beneficial to the electrical isolation between the sub-battery units, but also beneficial to the improvement of the power of the solar battery.

Optionally, the width w1 of the open area is 2000-5000um in the case that the volume resistivity of the open area is less than or equal to 1ohm "cm. Under the condition that the volume resistivity of the open area is greater than or equal to 3ohm "cm, the width w1 of the open area is 500-.

Optionally, the volumes of the power generation regions in the silicon wafer are substantially equal and the shapes thereof are substantially the same, and further, the volumes of the sub-battery units in the solar battery are substantially equal and the shapes thereof are substantially the same, so as to facilitate the improvement of the output power of the battery module formed by the sub-battery units.

Optionally, each sub-battery unit in the solar battery is a cuboid or a similar cuboid, so that the sub-battery units are conveniently connected in series. For example, the subcells may be cuboid-like with chamfers. The chamfer can simply and conveniently realize the consistent or nearly consistent area of the sub-battery units, so that the internal series connection is convenient to realize.

Optionally, the solar cell may further include a front passivation layer located on the light-facing surface of the silicon wafer, and/or a back passivation layer located between the silicon wafer and the anode and/or the cathode, and the front passivation layer and the back passivation layer both cover the open region, that is, the front passivation layer and the back passivation layer are complete layers, so that cutting or masking is not needed, the process is simple, and meanwhile, the passivation performance of the solar cell is improved, and further, the passivation performance of the cell module is improved.

For example, referring to fig. 2, the solar cell may further include a front passivation layer 7 on a light-facing side of the silicon wafer 1, and a back passivation layer 8 between the silicon wafer 1 and the positive and

negative electrodes

5 and 6, wherein the front passivation layer 7 and the back passivation layer 8 both cover the open region 11.

Optionally, when the conductive interconnection piece is a conductive wire, a connection line between the positive electrode of one sub-cell unit in the solar cell and the negative electrode of the adjacent sub-cell unit is parallel to one side of the solar cell, and further the conductive wire is parallel to the one side of the solar cell.

Optionally, the group of conductive interconnections is each conductive interconnection for series connection of two adjacent sub-battery cells in one solar battery, or the group of conductive interconnections is each conductive interconnection for series connection of two adjacent solar batteries. The battery pack further includes: the supplementary electrode is conductively connected with at least two of the conductive interconnection pieces, and when any one of the at least two conductive interconnection pieces is unreliable in connection, the supplementary electrode can be conductively connected to the rest conductive interconnection pieces, so that the reliability of conductive connection can be improved.

For example, referring to fig. 3, fig. 3 is a schematic structural diagram of a second solar cell string according to an embodiment of the present invention. Fig. 3 may be a bottom view looking from the backlight side of the solar cell string toward the light-facing side. A group of conductive interconnects shown in fig. 3 are each conductive interconnects for the series connection of two adjacent subcells within one solar cell. On the basis of fig. 1, for each conductive interconnection 16 in which two adjacent sub-battery cells in a solar battery are connected in series, the complementary electrode 9 is formed on the backlight surface of the silicon wafer and is disposed corresponding to the open area, the complementary electrode 9 is conductively connected to at least two of a group of conductive interconnections, and when any one of the at least two conductive interconnections 16 is unreliable, the complementary electrode 9 can be conductively connected to the rest of the conductive interconnections 16, so that the reliability of conductive connection can be improved.

It should be noted that, the supplementary electrode is disposed correspondingly to each group of conductive interconnection pieces, or some groups of conductive interconnection pieces are disposed correspondingly to the supplementary electrode, and the supplementary electrodes are not particularly limited to some groups of conductive interconnection pieces that are not disposed correspondingly.

Optionally, the supplementary electrode is a continuous strip. For the continuous strip-shaped complementary electrode, the extending direction of the complementary electrode is parallel to the extending direction of the open area.

Optionally, the supplementary electrode is one of a straight line, a broken line or a wavy line, and further the supplementary electrode is various in form. As shown in fig. 3, the supplemental electrode 9 is a straight line.

Optionally, the solar cell further comprises: and the isolation region is positioned between the p-type doped region and the n-type doped region in the power generation region and can play a role of electrical isolation so as to improve the output power of the solar cell. The width of the isolation area is 0.1-100um, and the width of the isolation area not only can play a good isolation role, but also can avoid waste.

For example, referring to fig. 4, fig. 4 shows a schematic structural diagram of a second solar cell in an embodiment of the present invention. In fig. 4, within the power generation region, there is an isolation region 13 between the p-type doped region 2 and the n-type doped region 3. The width w2 of the isolation region 13 is 0.1-100 um.

Optionally, the solar cell further comprises: and the third doping region is positioned on the light facing surface of the power generation region of the silicon wafer, the doping type of the third doping region can be the same as or opposite to that of the silicon wafer, and if the doping type of the third doping region is the same as that of the silicon wafer, the third doping region can be a Front surface field (BSF). If the doping type of the third doped region is opposite to that of the silicon wafer, the third doped region may be a Front Floating Emitter (FFE), and the efficiency of the solar cell may be improved regardless of BSF or FFE. The third doped region is disconnected at the position corresponding to the open region, that is, the third doped region is not arranged on the surface of the light-facing surface of the silicon wafer, which is opposite to the open region, so that the electrical isolation effect among the sub-battery units can be further improved, the mutual flow of current carriers among the adjacent sub-battery units can be further reduced, and the efficiency loss caused by shunting can be further reduced.

For example, referring to fig. 5, fig. 5 shows a schematic structural diagram of a third solar cell according to an embodiment of the present invention. On the basis of fig. 2, the solar cell in fig. 5 further includes: and a third doped region 12 positioned on the light-facing surface of the power generation region of the silicon wafer 1, wherein the third doped region 12 is disconnected at a position corresponding to the open region 11.

Optionally, each of the open areas is distributed in parallel at intervals along one side of the solar cell, and the open areas extend from one end of the solar cell to the other end of the solar cell, so that each of the sub-cell units also extends from one end of the solar cell to the other end of the solar cell, and each of the sub-cell units is arranged in a manner that long sides of the sub-cell units are parallel, which can effectively reduce the transmission distance of current on the solar cell, and further reduce the loss caused by an internal circuit.

For example, the solar cell open regions 11 shown in fig. 3 are arranged in parallel at intervals along one side of the solar cell, and the open regions 11 extend from one end of the solar cell to the other end thereof, and 4 sub-cell units of the solar cell are arranged in parallel with each other in a long side.

Optionally, the solar cell further comprises: the edge connecting electrodes positioned on two sides can be used as the integral output electrodes of the solar cells along the arrangement direction of each sub-cell unit, and the interconnection of the solar cells in the subsequent assembly interconnection is facilitated.

For example, referring to fig. 6, fig. 6 shows a schematic structural diagram of a fourth solar cell in an embodiment of the present invention. The solar cell shown with reference to fig. 6 includes: the edges at both sides along the arrangement direction of the 4 sub-battery cells are connected to the electrodes 10.

Optionally, the edge connection electrode is in a continuous strip shape or a discrete point shape, and further, the edge connection electrode has various forms. For example, referring to fig. 6, the edge connection electrode 10 is a continuous strip, a connection line between the positive electrode 5 of one sub-cell unit and the negative electrode 6 of the adjacent sub-cell unit in one solar cell in fig. 6 is parallel to one side of the solar cell, and in the process of using the conductive wire as the conductive interconnection member to conductively connect the positive electrode 5 of one sub-cell unit and the negative electrode 6 of the adjacent sub-cell unit in one solar cell, the conductive wire does not need to be bent, the process is simple, and the possibility of hidden cracking is less. In fig. 6, the positive electrode 5, the negative electrode 6 and the conductive interconnection 16 are made of the same material, and thus can be manufactured at one time, and the process is simple.

The shape of the edge connecting electrode 10 for discrete shapes may be circular, rectangular, or other shapes that facilitate interconnection or welding. The edge connection electrode may be a pad, etc., and is not particularly limited in this embodiment of the present invention.

Optionally, the solar cell further comprises: the passivation tunneling layer is positioned between the silicon chip and the p-type doped region and the n-type doped region, the passivation tunneling layer covers the open region, namely the passivation tunneling layer is a complete layer, so that cutting or masking is not needed, the process is simple, and meanwhile, the passivation tunneling layer can reduce the contact recombination rate, so that the efficiency of the solar cell is improved.

For example, referring to fig. 7, fig. 7 shows a schematic structural diagram of a fifth solar cell in an embodiment of the present invention. The solar cell further includes: and the passivation tunneling layer 14 is positioned between the silicon chip 1 and the doping layer, the passivation tunneling layer 14 covers the open region 11, and the passivation tunneling layer 14 is a complete layer. The p-type doped region 2 may be a p-type doped semiconductor film and the n-type doped region 3 may be an n-type doped semiconductor film.

The part of the backlight surface of the passivation tunneling layer, which is opposite to the empty opening area, can be provided with an intrinsic semiconductor area, so that the electrical isolation effect among the sub-battery units in the same solar battery is improved. As in fig. 7, the portion of the passivation tunneling layer 14 located opposite the open region, at the backlight side, may be provided with an intrinsic semiconductor region 15.

Optionally, the passivation tunneling layer is located on a backlight surface of the silicon wafer, the part opposite to the empty opening region is disconnected, the back passivation layer is arranged on the backlight surface of the passivation tunneling layer, the back passivation layer is arranged on the backlight surface of the empty opening region, and therefore in the same back contact solar cell, the electrical isolation effect between the sub-battery units is good. That is, the back side of the open region may be provided with the passivation tunneling layer and/or the back passivation layer.

For example, referring to fig. 8, fig. 8 shows a schematic structural diagram of a sixth solar cell in an embodiment of the present invention. Compared with fig. 7, in fig. 8, the passivation tunneling layer 14 is located on the backlight surface of the silicon chip 1 and is broken at the opposite portion of the open area 11, and the back passivation layer 8 is disposed on the backlight surface of the passivation tunneling layer and is disposed on the backlight surface of the open area 11 of the silicon chip 1. It should be noted that the thickness of the entire back passivation layer 8 may be substantially equal, and the back surface of the back passivation layer 8 in the opening may be designed to be concave-convex.

Optionally, in the same subcell, the p-type doped region is composed of a plurality of p-type doped subregions communicated with each other, and the n-type doped region is composed of a plurality of discrete n-type doped subregions, or, in the same subcell, the n-type doped region is composed of a plurality of n-type doped subregions communicated with each other, and the p-type doped region is composed of a plurality of discrete p-type doped subregions, and each p-type doped subregion in the same subcell can be formed at one time, or each n-type doped subregion in the same subcell can be formed at one time, and the process is simple.

For example, referring to fig. 9, fig. 9 is a schematic structural diagram of a seventh solar cell according to an embodiment of the present invention. In fig. 9, the left subcell, the p-doped region 2 is composed of 10 interconnected p-doped sub-regions 23, and the right subcell, the n-doped region 3 is composed of 10 interconnected n-doped sub-regions 33. In the same solar cell in fig. 9, the p-type doped region 2 of one subcell and the n-type doped region 3 of the adjacent subcell are aligned and parallel to one side of the solar cell, the n-type doped region 3 of one subcell and the p-type doped region 2 of the adjacent subcell are aligned and parallel to one side of the solar cell, and then are located in the same solar cell, and the connecting line of the positive electrode of one subcell and the negative electrode of the adjacent subcell is parallel to one side of the solar cell, so as to facilitate the layout of the conductive interconnection pieces.

Optionally, in the same subcell, each p-type doped region is composed of a plurality of p-type doped sub-regions independent of each other; and/or, in the same subcell, each n-type doped region is composed of a plurality of independent n-type doped sub-regions. For example, referring to fig. 10, fig. 10 is a schematic structural diagram of an eighth solar cell according to an embodiment of the present invention. In fig. 10, in 2 subcells, the p-type doped region 2 is composed of 10 p-type doped sub-regions 23 independent of each other, and the n-type doped region 3 is composed of 10 n-type doped sub-regions 33 independent of each other. In the same solar cell in fig. 10, the p-type doped region 2 of one subcell and the n-type doped region 3 of the adjacent subcell are aligned and parallel to one side of the solar cell, the n-type doped region 3 of one subcell and the p-type doped region 2 of the adjacent subcell are aligned and parallel to one side of the solar cell, and further in the same solar cell, the connecting line of the positive electrode of one subcell and the negative electrode of the adjacent subcell is parallel to one side of the solar cell, so as to facilitate the arrangement of the conductive interconnection piece.

Optionally, the p-type doped region of one subcell and the n-type doped region of an adjacent subcell are aligned and parallel to one edge of the solar cell, and then located in the same solar cell, a connection line between the anode of one subcell and the cathode of the adjacent subcell is parallel to one edge of the solar cell, and the conductive interconnection piece is convenient to set. Such as fig. 9 and 10 described above.

Referring to fig. 11, fig. 11 is a schematic structural diagram of a ninth solar cell according to an embodiment of the present invention. In fig. 11, the p-type doped region 2 is composed of 10 p-type doped sub-regions 23 independent of each other, and the n-type doped region 3 is composed of 10 n-type doped sub-regions 33 independent of each other. In the same solar cell in fig. 11, the p-type doped region 2 of one subcell is not aligned with the n-type doped region 3 of the adjacent subcell, the n-type doped region 3 of one subcell is not aligned with the p-type doped region 2 of the adjacent subcell, and further in the same solar cell, the connecting line of the positive electrode of one subcell and the negative electrode of the adjacent subcell is not parallel to any edge of the solar cell, and the arrangement forms of the p-type doped region, the n-type doped region, the positive electrode and the negative electrode are various.

Optionally, the light-facing surface and/or the backlight surface of the solar cell may be provided with a light trapping structure, for example, a textured structure, so as to increase the optical path. The light-facing surface and/or the backlight surface of the solar cell may be provided with a passivation antireflection layer or the like. In the embodiment of the present invention, this is not particularly limited.

Optionally, the p-type doped region and the n-type doped region are both in a shape like a Chinese character feng, and the shape like the Chinese character feng is divided into a vertical region and a penetrating region; the penetrating area is parallel to the arrangement direction of each sub-battery unit; the positive electrode and the negative electrode are in a shape like a Chinese character feng, the positive electrode consists of a first contact electrode and a first connecting electrode, the first connecting electrode is arranged on a penetrating region of the p-type doping region, and the first contact electrode is arranged on a vertical region of the p-type doping region; the negative electrode is composed of a second contact electrode and a second connecting electrode, the second connecting electrode is arranged on a penetrating region of the n-type doped region, the second contact electrode is arranged on a vertical region of the n-type doped region, and then the p-type doped region, the n-type doped region, the positive electrode and the negative electrode are diversified in shape and form. The conductive interconnection conductively connects the first connection electrode of one sub-cell unit and the second connection electrode of an adjacent sub-cell unit to connect the adjacent sub-cell units in series.

As shown in fig. 12, fig. 12 is a schematic structural diagram of a first solar cell with a conductive interconnection in an embodiment of the present invention. In fig. 12, both the p-type doped region 2 and the n-type doped region 3 are "foe" shaped, and as for the p-type doped region 2, the "foe" shaped is divided into a vertical region 21 and a penetrating region 22, the penetrating region 22 is parallel to the arrangement direction of each subcell unit, both the anode 5 and the cathode 6 are "foe" shaped, the anode 5 is composed of a first contact electrode 51 and a first connection electrode 52, the first connection electrode 52 is disposed on the penetrating region 22 of the p-type doped region 2, and the first contact electrode 51 is disposed on the vertical region 21 of the p-type doped region 2. For the n-type doped region 3, the shape of Chinese character feng is divided into a vertical region 31 and a penetrating region 32, the penetrating region 32 is parallel to the arrangement direction of each subcell unit, the negative electrode 6 is composed of a second contact electrode 61 and a second connection electrode 62, the second connection electrode 62 is arranged on the penetrating region 32 of the n-type doped region 3, and the second contact electrode 61 is arranged on the vertical region 31 of the n-type doped region. The conductive interconnect 16 conductively connects the first connection electrode 52 of one sub-cell and the second connection electrode 62 of an adjacent sub-cell to connect the adjacent sub-cells in series. Referring to fig. 13, fig. 13 is a partially enlarged schematic view of a solar cell with a conductive interconnection according to an embodiment of the present invention.

The embodiment of the utility model provides a still provide a battery pack's production method, include following step:

step S1, providing a solar cell; the solar cell comprises a silicon wafer, a doping layer, a positive electrode and a negative electrode; the silicon chip comprises at least two power generation regions and an open region positioned between the adjacent power generation regions; the doping layer is formed on a backlight surface of a power generation region in the silicon wafer and is disconnected at a position corresponding to the open region; the doping layer comprises a p-type doping region and an n-type doping region which are opposite in doping type; the anode is formed on a backlight surface of the p-type doped region; and the negative electrode is formed on the backlight surface of the n-type doped region.

The manufacturing method of this silicon chip can refer to the manufacturing method of silicon chip among the prior art, and the embodiment of the utility model provides a do not do specifically to this and restrict.

Step S2, providing a conductive interconnect.

Step S3, connecting the positive electrode of one solar cell and the negative electrode of the adjacent solar cell by the conductive interconnection member in a conductive manner, so as to connect the adjacent solar cells in series.

Step S4, simultaneously connecting the sub-cells in the solar cell in series with the conductive interconnect.

Optionally, under the condition that the volume resistivity of the open area of the first solar cell is greater than that of the open area of the second solar cell, the width of the open area of the first solar cell is less than or equal to that of the open area of the second solar cell, and further, the width of the open area is beneficial to electrical isolation among the sub-cell units, the open area is not too large, the silicon wafer is not wasted, and other areas can be used as a part of the sub-cell units, so that the power of the solar cell is promoted.

In the embodiment of the present invention, the conductive interconnection is not specifically limited, and is specifically determined according to the actual conductive connection requirement, in the embodiment of the present invention, this is not specifically limited.

Optionally, in the case where the conductive interconnect is a conductive wire, the step of providing a conductive interconnect may include: coating a conductive adhesive material on the conductive wire; the step of electrically connecting in steps S3 and S4 includes: electrically connecting the positive electrode of one solar cell and the negative electrode of the adjacent solar cell at 80-350 ℃ by using an electric wire coated with an electrically conductive bonding material so as to serially connect the adjacent solar cells; and connecting the sub-battery units in the solar battery in series at 80-350 ℃ by using a conductive wire coated with a conductive bonding material.

Firstly coating a conductive adhesive material on a conductive wire, and then connecting the positive electrode of one solar cell and the negative electrode of the adjacent solar cell in a conductive way by using the conductive wire coated with the conductive adhesive material at 80-350 ℃ so as to connect the adjacent solar cells in series; and at the temperature of 80-350 ℃, the conductive wires coated with the conductive bonding materials are simultaneously connected with the sub-battery units in the solar battery in series, so that the reliability of conductive connection can be improved.

Each sub-battery unit in one solar battery does not need to be connected in series in advance, and each solar battery and each sub-battery unit in each solar battery are connected in series by adopting the conductive interconnection piece in the process of forming the assembly, so that the process is simple, and the production efficiency is improved. Moreover, each sub-battery unit in one solar battery is not physically divided, and is also a physical whole, so that the yield reduction risk caused by internal interconnection is reduced, and the fragment rate is reduced.

It should be noted that, for the cell module, reference may be made to the above description of the solar cell, and the same or similar beneficial effects can be achieved, so that the details are not repeated herein to avoid redundancy.

The embodiments of the present invention have been described with reference to the accompanying drawings, but the present invention is not limited to the above-mentioned embodiments, which are only illustrative and not restrictive, and those skilled in the art can make many forms without departing from the spirit and scope of the present invention, and all of them fall within the protection scope of the present invention.

Claims

1. A battery assembly, comprising: at least two solar cells, a conductive interconnect;

the anode is formed on a backlight surface of the p-type doped region;

2. The battery assembly of claim 1, wherein the conductive interconnect is a conductive wire.

3. The battery assembly of claim 1, wherein the conductive interconnects are conductive traces in a conductive backsheet.

4. The battery pack of claim 2, wherein the conductive wires have a dimension of 0.01-0.8mm in a direction perpendicular to a length direction of the conductive wires.

5. The battery assembly of claim 1, wherein the width of the open area is 500-.

6. The battery assembly of claim 1, wherein the width of the open area is 2000-5000um in the case where the volume resistivity of the open area is less than or equal to 1ohm "cm;

7. The battery assembly of claim 2, wherein, in the case where the conductive interconnect is a conductive wire, a line connecting the positive electrode of one subcell of one solar cell and the negative electrode of an adjacent subcell is parallel to one side of the solar cell.

8. The battery module of any of claims 1-6, wherein the solar cell further comprises: and the isolation region is positioned between the p-type doped region and the n-type doped region in the power generation region, and the width of the isolation region is 0.1-100 um.

9. The battery module of any of claims 1-6, wherein the solar cell further comprises: the third doped region is positioned on the light facing surface of the power generation region of the silicon wafer; and the third doped region is disconnected at the position corresponding to the empty opening region.

10. The battery module of any of claims 1-6, wherein the solar cell further comprises: a passivation tunneling layer located between the silicon wafer and the doping layer;

the passivation tunneling layer covers the open area.

11. The battery assembly of any of claims 1-6, wherein the p-type doped region is comprised of a plurality of interconnected p-type doped sub-regions and the n-type doped region is comprised of a plurality of discrete n-type doped sub-regions in the same subcell;

12. The battery module of any of claims 1-6, wherein the solar cell further comprises: the front passivation layer is positioned on the light facing surface of the silicon wafer;

13. The cell assembly according to any one of claims 1-6, wherein each of the open regions is spaced apart from and parallel to one side of the solar cell, and the open regions extend from one end of the solar cell to the other end of the solar cell.

14. The battery module of any of claims 1-6, wherein the solar cell further comprises: the edges at both sides are connected with electrodes, and the both sides are along the arrangement direction of each sub-battery unit.

15. The battery pack of claim 14, wherein the edge connection electrodes are in the form of continuous strips or discrete dots.

16. The battery assembly according to any one of claims 1-6, wherein the p-type doped region and the n-type doped region are both "torx" shaped, and the "torx" shape is divided into a vertical region and a through region; the penetrating area is parallel to the arrangement direction of each sub-battery unit;

the anode and the cathode are in a shape like Chinese character feng;

17. The battery assembly of any of claims 1-6, further comprising: a supplemental electrode; the supplemental electrodes are conductively connected to at least two of a set of conductive interconnects; the group of conductive interconnections are each conductive interconnection for series connection of two adjacent sub-battery cells in one solar battery, or each conductive interconnection for series connection of two adjacent solar batteries.