3619 results about "Battery bank" patented technology

The invention is applicable to the field of photovoltaic technology, and provides a back contact solar cell, which comprises a silicon substrate, non-recessed areas and recessed areas are alternately arranged on the backlight surface of the silicon substrate, and the silicon substrate is provided with extending parts extending and protruding to the upper parts of the recessed areas at the edges of the non-recessed areas and the recessed areas; the first dielectric layer and the first polarity doping layer are sequentially stacked on the non-sunken region and the extension part; the second dielectric layer comprises a first part stacked on the first polarity doping layer and a second part stacked in the sunken region; the second polarity doped layer is stacked on the first portion and the second portion. Under the shielding effect of the extension part, the first polarity doping layer in the non-recessed area is effectively isolated from the second polarity doping layer in the recessed area, and electric leakage is avoided.

The invention discloses an optical storage and charging integrated charging station operation optimization system and method, and relates to the technical field of charging stations, and the system comprises an energy storage module, a charging pile module, a photovoltaic module, and an optical storage and charging management platform. The energy storage module comprises a plurality of energy storage battery packs, the charging pile module comprises a plurality of charging piles, the photovoltaic module comprises a plurality of photovoltaic panel groups, the plurality of photovoltaic panel groups form a photovoltaic array, and the photovoltaic storage and charging management platform comprises a data acquisition module, a data processing center and an optimization control module. According to the scheme, by accurately analyzing the power generation power change curve and the power generation efficiency of the photovoltaic module and combining the state of the energy storage module and the requirements of the charging pile, photovoltaic and energy storage cooperative power supply is achieved, photovoltaic power generation can be fully utilized, the light abandoning phenomenon is reduced, meanwhile, the energy storage charging and discharging strategy is optimized, the overall energy utilization rate is increased, and dependence on power grid electric energy is reduced; and energy utilization is more reasonable and efficient.

The invention relates to the technical field of back contact batteries, in particular to a back contact battery assembly and a photovoltaic system.The back contact battery assembly comprises a battery string, the battery string comprises battery pieces connected in series, and the battery pieces comprise a first battery piece, a second battery piece and a first insulating strip, the first insulating strip is arranged at one end, close to the first battery piece, of the second battery piece, the first bus bar is arranged on one side, back on to the second battery piece, of the first insulating strip, the first insulating strip and the first bus bar are arranged in an extending mode in the second direction, and the first welding strip is used for electrically connecting the first bus bar and the first battery piece. The first insulating strip is provided with an extension section extending out of the first bus bar, the extension section extends out of the second battery piece, and in the thickness direction of the second battery piece, the orthographic projection of the extension section at least partially coincides with the orthographic projection of the first battery piece. According to the invention, the effective light-receiving area of the cell module can be increased, the conversion efficiency of the module is improved, the observed area of the bus bar from one side of the light-receiving surface is smaller and even can be completely hidden, meanwhile, the production difficulty can be effectively reduced, the risks of short circuit, subfissure and fragmentation of the cell piece are reduced, and the reliability is improved.

The invention is suitable for the field of photovoltaic technology, and provides a battery assembly and a photovoltaic system, and the battery assembly comprises a plurality of battery pieces, each battery piece comprises a chamfer edge and a straight edge which are parallel to each other, and the plurality of battery pieces are partially overlapped in a first direction to form a battery string. The plurality of battery strings are partially overlapped along the second direction to define a plurality of closed areas, the plurality of battery pieces are partially overlapped to eliminate the piece spacing, and the plurality of battery strings are partially overlapped to define a plurality of closed areas to reduce the string spacing; according to the photovoltaic module, more battery pieces can be arranged in a limited area, the utilization rate of the space area and the power generation power of the module are improved, in addition, due to the formation of the closed area, the light leakage condition of the battery module can be improved, and the power generation efficiency of the photovoltaic module can be improved by utilizing light rays in the intervals of the battery strings; the photovoltaic module is better in overall attractiveness, and the production efficiency can be improved.

The invention relates to the technical field of back contact cells, and particularly discloses a back contact cell assembly and a photovoltaic system.The cell assembly comprises a cell string, a first insulating strip, a second insulating strip, a first electrode, a second electrode and a second electrode, the cell string comprises cells which are connected in series, the cells comprise a first cell and a second cell which are arranged in the first direction, and the first cell is arranged at the end of the cell string; the first insulating strip is arranged at one end, close to the first battery piece, of the second battery piece, the first bus bar is arranged on one side, back on to the second battery piece, of the first insulating strip, the first insulating strip and the first bus bar are arranged in an extending mode in the second direction, and the first welding strip is used for electrically connecting the first bus bar and the first battery piece. The end, close to the first battery piece, of the first bus bar is provided with an extension section, the extension section extends out of the edge of the first insulating strip in the first direction and is electrically connected with the first welding strip, and a connecting end is formed at the connecting position of the extension section and the first welding strip. According to the invention, the effective light-receiving area of the cell module can be increased, the conversion efficiency of the module is improved, the observed area of the bus bar from one side of the light-receiving surface is smaller, even the bus bar can be completely hidden and is more beautiful, meanwhile, the production difficulty can be effectively reduced, the risks of subfissure and fragmentation of the cell piece are reduced, and the reliability is improved.

The invention discloses a back contact solar cell, an assembly and a system. The back contact solar cell comprises a silicon substrate, the back surface of the silicon substrate comprises a plurality of first areas and a plurality of second areas, the first areas and the second areas are arranged at intervals, and each of the first areas and the second areas comprises a passivation selective contact area and a non-passivation selective contact area; the non-passivation selective contact area comprises a passivation anti-reflection layer arranged on the surface of the silicon substrate; the passivation selective contact area of the first area comprises a first passivation layer, a selective transmission layer and a first metal electrode which are sequentially stacked on the surface of the silicon substrate from inside to outside. According to the back contact solar cell, the passivation layer and the selective transmission layer are arranged in the first region and combined with the passivation anti-reflection layer, the excellent passivation contact effect is achieved, a narrow-band-gap highly-doped silicon material does not need to be used, the optical parasitic absorption loss is reduced, the photoelectric conversion efficiency is improved, and then the performance of the back contact solar cell is improved.

The embodiment of the invention relates to the field of photovoltaic technology, and provides a photovoltaic module, the photovoltaic module comprises a battery string, an insulating layer, a bus bar and a conductive bridging part, the battery string comprises a plurality of battery pieces, the back surface of each battery piece is provided with a welding strip, and the plurality of battery pieces are connected in series through the welding strips; the insulating layer is arranged on one side, far away from the battery piece, of the welding strip, and the insulating layer is provided with an avoiding area, so that part of the welding strip is exposed from the avoiding area to form a welding strip exposing part; the bus bar is arranged on one side of the insulating layer away from the solder strip; the conductive bridging part is arranged between the bus bar and the solder strip exposing part, so that the bus bar and the solder strip exposing part are conductively connected through the conductive bridging part. The embodiment of the invention is at least beneficial to improving the maximum output power of the back contact battery assembly.

The invention provides a device and a method for extracting water from air operated under all working conditions. The device comprises a solar power supply unit, a salt-carrying hydrogel adsorption-desorption unit, an electric heating desorption unit, a water vapor condensation and collection unit and a PID control unit. The solar power supply system comprises a solar photovoltaic panel, an MPPT (maximum power point tracking) type photovoltaic inverter and a storage battery, the salt-carrying hydrogel adsorption-desorption unit comprises hydrophilic porous hydrogel and a LiCl / CaCl2 composite adsorption material, and the electric heating desorption unit comprises a copper heat-conducting plate loaded with the adsorption material and an electric heating sheet. The water vapor condensation and collection unit is composed of four finned radiators and two semiconductor chilling plates. The PID control unit is composed of a temperature and humidity sensor and a control circuit, wherein the temperature and humidity sensor is connected to the radiators and the front side of the adsorption bed. Water vapor in the environment is enriched through an efficient salt-loaded adsorbent packed bed, desorption is driven in two modes of solar photo-thermal and electric heating, desorbed high-humidity airflow passes through a fin type cooling fin connected with a semiconductor and then is condensed into liquid water, and the process of taking water from air is completed through a collector below. According to the device, low-energy-consumption air water taking under the humidity of 15%-100% can be achieved by controlling the operation time of all the units, the device is portable and compact, the automation degree is high, and high-water-yield air water taking is achieved by using solar photo-thermal and power generation as energy input.

The invention is suitable for the field of photovoltaic technology, and provides an electrode structure of a back contact cell, a cell piece and a solar cell module, and the electrode structure comprises a main grid which is closest to a first edge of the back contact cell; the first connection grid line is connected with the main grid, the pad point and the main grid are arranged at intervals in the first direction, the first end of the second connection grid line is in electric contact with the pad point, the second end of the second connection grid line extends in the second direction, and the first direction intersects with the second direction. When the welding strip is arranged on the battery piece and connected with the pad point, the welding strip extends to the second connecting grid line, so that burrs on the edge of the welding strip are blocked by the second connecting grid line, the burrs on the edge of the welding strip are prevented from directly puncturing the insulating paste to be communicated with the opposite grid line, and the second connecting grid line plays a role in protecting the battery piece. The risk of local short circuit of the battery piece is avoided, and the yield of the battery piece can be effectively improved.

The utility model is suitable for the technical field of solar cells, and provides a back contact cell assembly and a photovoltaic system.The back contact cell assembly comprises a cell string, an insulating strip and a bus bar, the cell string comprises a plurality of cell pieces connected in series, the cell pieces are distributed in the first direction, the insulating strip is arranged on the backlight face of the cell pieces in the second direction, the first direction and the second direction intersect, the bus bars are arranged on the sides, away from the battery pieces, of the insulating strips in the second direction, and the insulating strips cover the bus bars. Therefore, the bus bar is hidden in the backlight surfaces of the plurality of battery pieces, and the bus bar cannot be observed from one side of the light receiving surface, so that the overall color of the front surface of the back contact battery assembly is uniform and beautiful. And meanwhile, the insulating strip can be arranged between the bus bar and the battery piece, so that the short circuit problem is avoided.

The invention relates to the technical field of solar cells, and provides a back contact cell assembly and a photovoltaic system.The back contact cell assembly comprises a plurality of cell strings and bus bars, a first welding strip comprises a body section, a bent section and an extending section, and the body section is welded to a first cell piece through a welding spot; the extension section extends between a second welding strip and a fourth welding strip which are adjacent to each other on the second battery piece and is at least partially overlapped with the bus bar so as to be welded with the bus bar, and the body section and the extension section are connected through a bending section; in the thickness direction of the back contact battery assembly, the extension section and the second welding strip do not have an overlapped part, and in the second direction, the distance D between the extension section of at least one first welding strip and the adjacent second welding strip meets the following relational expression: 1 mmlt; d < = 0.63 * arctan (1.8 * L * D2 + H) * (D1-W). Therefore, the hidden crack risk in the lamination process can be reduced, the electrical loss of the assembly can be reduced, the double-sided rate of the assembly can be improved, and the difficulty of the manufacturing process can be reduced.

The utility model relates to the technical field of solar cells, and provides a main-grid-free electrode structure, an IBC solar cell sheet, a cell assembly and a photovoltaic system, in the IBC solar cell sheet, a first connection grid line and a second connection grid line are arranged at a first disconnection area, the first connection grid line and the second connection grid line are not contacted with a first fine grid, and the second connection grid line is not contacted with a second fine grid. The first connecting grid line and the second connecting grid line are connected with the part, closest to the third edge, of the second fine grid, and the first end welding point is arranged between the first connecting grid line and the second connecting grid line and makes contact with the first connecting grid line and the second connecting grid line. Therefore, when the welding strip is subsequently welded with the first end part welding point, due to the arrangement of the first connecting grid line and the second connecting grid line, the risk of hidden cracks during welding can be reduced, the yield of the battery piece is improved, and meanwhile, the overall convergence of the second fine grid can be realized.

The invention relates to the technical field of power supply control, in particular to a power supply control system of a photovoltaic energy storage charging pile, which comprises a load power analysis module, an energy storage battery pack management module, a charging and discharging dynamic regulation and control module, an abnormal charging and discharging correction module and a power distribution optimization module. According to the invention, power demand analysis and battery management optimization are carried out. By dynamically analyzing the instantaneous power and fluctuation of the photovoltaic energy storage charging pile, the stability of the load can be more accurately judged, adjustment is carried out according to different fluctuation levels, finer energy allocation is achieved, and by monitoring and adjusting the internal resistance of the battery in real time, abnormal charging and discharging behaviors can be found and corrected in time. According to the invention, safe operation and reliability of energy output are ensured, the utilization rate of photovoltaic power generation can be improved through optimized power distribution, the power supply proportion of the power grid and photovoltaic power generation is dynamically adjusted according to the actual power supply condition, energy waste is effectively reduced, and the economical efficiency and environmental protection property of overall electric energy are improved.

The invention relates to the technical field of back contact batteries, and particularly discloses a back contact battery assembly, which comprises a battery string, a first insulating strip, a first bus bar, a second insulating strip, a second bus bar, a second bus bar, a third bus bar and a fourth bus bar, the first bus bar is arranged on the side, back on to the second battery piece, of the first insulating strip, the first insulating strip and the first bus bar extend in the second direction, the first welding strip is used for being electrically connected with the first bus bar and the first battery piece, and in the first direction, the two ends of the first insulating strip are provided with a first widened section and a second widened section which extend out of the edge of the first bus bar; the first widening section and the second widening section are sequentially arranged in the direction away from the first battery piece, and the width of the second widening section is smaller than that of the first widening section. According to the invention, the effective light-receiving area of the battery assembly can be increased, the conversion efficiency of the assembly can be improved, the observed area of the bus bar from one side of the light-receiving surface is smaller, even the bus bar can be completely hidden and is more beautiful, meanwhile, the production difficulty can be effectively reduced, the risks of short circuit, subfissure and fragmentation of the battery piece are reduced, the reliability is improved, and the double-sided rate of the battery assembly can be ensured.

The invention provides a back contact battery assembly and a photovoltaic system, a back contact battery can comprise a plurality of battery strings and a bus bar, a first welding strip comprises a first body section connected with a first battery piece and a first extension section which extends to a second battery piece and is at least partially overlapped with the bus bar, the second welding strip comprises a second body section and a second extension section. And in the thickness direction of the back contact battery assembly, the first extension section and the second extension section do not have an overlapped part. The bus bar is provided with a protruding section protruding towards the side away from the second battery piece at the second extension section, and the bus bar is provided with a recessed section recessed towards the side of the second battery piece at the first extension section. For at least part of the cross section of the bus bar, the included angle alpha between the connecting line between the highest point of the convex section and the lowest point of the adjacent concave section and the plane where the second battery piece is located meets the following formula: 0.075 < = tan alpha < = 3. In this way, the hidden crack risk in the laminating process can be reduced.

The invention is applicable to the field of photovoltaic technology, and provides a solar cell, a cell assembly and a photovoltaic system.The solar cell comprises a silicon substrate, the silicon substrate is provided with a backlight face and a light facing face which are oppositely arranged, a plurality of grid lines and a plurality of microarrays are arranged on the backlight face side by side in the first direction, and the grid lines extend in the second direction; the microarray comprises a plurality of arranged microstructure units, an included angle is formed between the microarray and the grid line, and the first direction is crossed with the second direction; the length of the silicon substrate in the second direction is L, the range of the two side edges, parallel to the first direction, of the silicon substrate extending towards the center line by L / 9 is an edge area, the included angle in the edge area is alpha, the included angle in the area close to the position of the center line is beta, and the angle of alpha is larger than that of beta. The absorption path of light in the silicon wafer is increased, the diffuse reflection effect of reflected light of backlight surfaces in different areas is promoted, and therefore the absorption efficiency of the light is improved.

The invention is suitable for the technical field of solar cells, and provides a back contact solar cell, a cell assembly and a photovoltaic system, and the solar cell comprises a silicon substrate, the backlight surface of which is provided with a first region and a second region; the first passivation layer is arranged in the first region; the first doping layer is arranged on one surface, deviating from the silicon substrate, of the first passivation layer; the second passivation layer is arranged in the second region; the second doping layer is arranged on one surface, deviating from the silicon substrate, of the second passivation layer; at a preset position, an electric leakage contact layer is arranged in at least partial region between the first doping layer and the second doping layer, the electric leakage contact layer is connected with the first doping layer and the second doping layer, the thickness of the electric leakage contact layer is greater than that of the second passivation layer, and the ratio of the thickness of the electric leakage contact layer to the thickness of the second passivation layer is less than 4. According to the back contact solar cell, hot spot effect management and control can be achieved, normal power generation under a certain weak light condition is not affected, and hot spot effect management and control and power generation capacity of the back contact solar cell can be well balanced.

The invention discloses a back contact solar cell, an assembly and a photovoltaic system, and relates to the field of silicon solar cells. The back contact solar cell comprises a silicon substrate, a first doping layer, a second doping layer, a positive electrode grid line, a negative electrode grid line and a first PAD part. The first doping layers and the second doping layers are alternately arranged along a first direction; the first doped layer comprises a first sub-doped layer, and the second doped layer comprises a second sub-doped layer adjacent to the first sub-doped layer; the second doping sub-layer and the first doping sub-layer form an electric leakage composite contact structure at a preset position; the positive grid line comprises a first sub-positive grid line arranged on the first sub-doping layer, and the negative grid line comprises a first sub-negative grid line arranged on the second sub-doping layer; each group of first PAD parts comprises a first PAD point and a second PAD point, the first PAD point is electrically connected with the first sub positive grid line, and the second PAD point is electrically connected with the first sub negative grid line. By implementing the method, the hot spot effect can be accurately represented at the battery end.

The utility model relates to the field of solar photovoltaic technology, in particular to a battery piece, a battery piece stacking structure and a solar battery assembly. In the battery piece, the plurality of first isolation bulges are arranged on the back surface of the battery piece body, and the first isolation bulges protrude out of the back surface of the battery piece body; the plurality of second isolation bulges are arranged on the front surface of the battery piece body and protrude out of the front surface of the battery piece body; the plurality of grid lines 40 are arranged on at least one surface of the battery piece body; in the thickness direction of the battery piece body, the height of at least one of the first isolation bulges and the second isolation bulges is greater than that of all the grid lines; and the plurality of second isolation bulges are projected on the back surface of the battery piece body, and the projection does not intersect with the first isolation bulges, or the projection partially intersects with the first isolation bulges. The arrangement of the first isolation protrusions and the second isolation protrusions effectively prevents the grid lines from making contact with the front face of the battery piece body.

The invention discloses a wind-solar complementary intelligent charging system and heat management optimization. The system comprises a wind power generation unit, a photovoltaic power generation unit, an energy storage unit, an intelligent control unit and a heat management unit, the wind power generation unit adopts an efficient wind generating set, is provided with an intelligent control system, and can automatically adjust a pitch angle and a yaw angle according to real-time wind speed and wind direction; the photovoltaic power generation unit selects a high-efficiency photovoltaic cell assembly and tracks the position of the sun in real time in combination with an intelligent light following system; and the energy storage unit adopts a high-performance energy storage battery pack and a battery management system. Through accurate prediction and analysis of local wind and light resources, dynamic configuration and cooperative power generation of the wind power generation unit and the photovoltaic power generation unit are realized. Compared with a traditional fixed configuration mode, local wind and light resources can be fully utilized, and the power generation efficiency is improved. Meanwhile, the multi-energy complementary cooperative power generation technology is adopted, organic combination of wind and light power generation and energy storage is achieved, and stable power supply of the system is ensured.

The invention relates to the technical field of solar cells, and particularly discloses a back contact cell, a back contact cell string, a cell assembly and a photovoltaic system.The back contact cell comprises first grid lines and second grid lines which are alternately arranged in the first direction; the first Pad points and the second Pad points are alternately arranged in the second direction, the first Pad points are connected with the first grid lines, and the second Pad points are connected with the second grid lines; wherein the first grid line comprises a first grid line body and a third grid line, and the first grid line body and the third grid line are connected into an integrated structure; along the first direction, the third grid line is arranged at the corresponding first pad point, and the width of the third grid line is greater than that of the first grid line body. The problem of welding tension in the prior art can be solved, and the connection reliability between the welding strip and the fine grid is improved.

The invention relates to the technical field of solar cells, and provides a back contact cell, a cell assembly and a photovoltaic system, a first passivation contact structure of the back contact cell is arranged on a first region, and the first passivation contact structure can comprise a first passivation layer and a first doping layer, the included angle between the side wall face of the first passivation contact structure and the surface of the second area is larger than or equal to 60 degrees and smaller than 90 degrees, and the second passivation contact structure is arranged on the second area and comprises a second passivation layer and a second doping layer. The second passivation layer is stacked on the second region and extends from the second region to the sidewall surface and at least a partial region of the back surface of the first passivation contact structure, and the second doping layer is disposed on the second passivation layer. Therefore, the shape-preserving deposition of the second passivation layer on the side wall surface can be optimized, and the passivation effect on the side wall surface of the first passivation contact structure is improved, so that the performance of the back contact battery is improved.

The invention provides a back contact battery assembly and a photovoltaic system, a back contact battery can comprise a plurality of battery strings and a bus bar, each battery string comprises a plurality of battery pieces which are sequentially connected in series along a first direction, and the plurality of battery pieces comprise a first battery piece arranged at the end part of the battery string and a second battery piece adjacent to the first battery piece; the back of the first cell is provided with a first solder strip, and the back of the second cell is provided with a second solder strip. The first welding strip is connected with the first battery piece and is provided with an extension section which extends to the second battery piece and is at least partially overlapped with the bus bar, and the second welding strip comprises a main body section which is not overlapped with the bus bar and an extension section which is overlapped with the bus bar; the main body section extends along the first direction, an extension line of the main body section in the first direction is at least partially overlapped with the first welding strip, the extension section and the main body section are mutually spaced in the second direction, and the extension section and the extension section do not have an overlapped part in the thickness direction of the back contact battery assembly. In this way, the hidden crack risk in the laminating process can be reduced.

The invention provides a back contact battery, a battery assembly and a photovoltaic system. The back contact battery comprises a battery substrate, a plurality of first fine grids and a plurality of second fine grids; the battery substrate comprises a first edge area and a middle area which are sequentially arranged along a first direction; the first fine grids and the second fine grids extend along a second direction, and the second direction is crossed with the first direction; in the middle region, the first fine grids and the second fine grids are alternately arranged along the first direction; in the first edge region, the plurality of first fine grids are sequentially arranged along the first direction; and the second fine grid avoids the first edge region. According to the back contact battery provided by the embodiment of the invention, the second fine grid avoids the first edge region, so that when the back contact battery is applied to the battery assembly, the bus bar can be arranged in the first edge region, the battery assembly does not need to arrange an isolating strip between the bus bar and the back contact battery, and the thickness of the battery assembly can be reduced.

The invention relates to the technical field of solar cells, and provides a back contact cell, a cell assembly and a photovoltaic system, in the back contact cell, first bus grid lines and first connecting grid lines are continuous at a first edge serial connection area and a second edge serial connection area, the first connecting grid line is located between the two first bus grid lines, and the second connecting grid line is located between the two first bus grid lines. The first insulating layer is arranged on the portion, corresponding to the first edge serial connection area, of the first bus grid line, the second insulating layer is arranged on the portion, corresponding to the second edge serial connection area, of the first connecting grid line, and the first auxiliary connecting line is connected with at least two second grid lines located on the same side of the first bus grid line set. The second auxiliary connecting line is connected with the first bus grid line located on one side of the first connecting grid line and at least one first grid line adjacent to the first bus grid line. Therefore, through special design of the electrode structure, the cold solder joint influence caused by the insulating layer can be reduced or even eliminated, so that the electrical performance of the back contact battery is improved.

The invention relates to the technical field of solar cells, and provides a back contact cell, a cell assembly and a photovoltaic system, a first passivation contact structure of the back contact cell is arranged in a first region, and an insulation region is provided with a first insulation dielectric layer; the first insulating dielectric layer is provided with a body part located on the insulating region and an insulating extension part extending to the first passivation contact structure. The second passivation contact structure is provided with a first contact extension part covering the body part and a second contact extension part covering the insulation extension part, a through groove is formed in a stacked structure formed by the insulation extension part and the second contact extension part in the thickness direction, and the first conductive structure is arranged at the through groove; the second conductive structure is disposed at least on a portion of the second passivation contact structure corresponding to the second region. Therefore, through the optimal design of the first insulating dielectric layer and the second passivation contact structure, the passivation effect can be improved, the electrical isolation effect can be improved, the electric leakage risk can be reduced, and the performance of the back contact battery can be improved.

The invention provides a back contact solar cell and a solar cell module, the back contact solar cell comprises a silicon wafer and a grid line structure, and the grid line structure comprises main grid lines and fine grid lines connected with the main grid lines. The grid line structure comprises a plurality of middle grid line sub-structures arranged in the first direction, a first edge grid line sub-structure closest to the first edge and a second edge grid line sub-structure closest to the second edge. The distance between the center line of the main grid line of the first edge grid line substructure and the center line of the main grid line of the adjacent middle grid line substructure is larger than the distance between the center lines of the main grid lines of any two adjacent middle grid line substructures. The distance between the center line of the main grid line of the second edge grid line substructure and the center line of the main grid line of the adjacent middle grid line substructure is larger than the distance between the center lines of any two adjacent middle grid line substructures. The back contact solar cell solves the problem of damage caused by stress concentration at the edge of the cell.

The invention relates to the technical field of solar cells, and provides a back contact cell, a cell assembly and a photovoltaic system, in the back contact cell, a first collection grid line is interrupted at a first edge serial connection area and is continuous at a second serial connection area, and a first bus grid line is continuous at the first edge serial connection area and the second serial connection area. The first edge bus line is closer to the first edge than the first edge serial connection area, and the first edge bus line is electrically connected with at least part of the first collection grid line and is electrically connected with the first bus grid line. And a first insulating layer is arranged on the part, corresponding to the first serial connection area, of the first bus grid line. The first auxiliary connecting line is arranged in the first edge serial connection area, in the second direction, at least one side of the first bus grid line is provided with the first auxiliary connecting line, and the first auxiliary connecting line is connected with at least two second grid lines located on the same side of the first bus grid line. Therefore, through the arrangement of the first auxiliary connecting line, the influence caused by pseudo soldering can be reduced, so that the efficiency of the back contact battery is ensured.

The embodiment of the invention relates to the field of photovoltaic technology, and provides a photovoltaic module, the photovoltaic module comprises a battery string, an insulating layer and a bus bar, the battery string comprises a plurality of battery pieces, the back surface of each battery piece is provided with a welding strip, and the plurality of battery pieces are connected in series through the welding strips; the insulating layer is arranged on one side, far away from the battery piece, of the welding strip, and the insulating layer is provided with an avoiding area, so that part of the welding strip is exposed from the avoiding area to form a welding strip exposed part; the bus bar is arranged on the side, away from the welding strip, of the insulating layer, the bus bar is provided with an abutting part in a protruding mode towards the welding strip exposing part, and the abutting part abuts against the welding strip exposing part so that the bus bar can be conductively connected with the welding strip. The embodiment of the invention is at least beneficial to improving the maximum output power of the back contact battery assembly.

The invention is applicable to the field of photovoltaic technology, and provides a solar cell, a cell module and a photovoltaic system.The solar cell comprises a silicon substrate, and a backlight surface of the silicon substrate is provided with a plurality of grooves; the doped region structures are at least arranged at the plurality of grooves, each doped region structure comprises an internal expansion layer arranged in the silicon substrate, and a passivation layer and a first doped layer which are sequentially arranged on the backlight surface of the silicon substrate, and the passivation layer is provided with a plurality of hole structures; for at least part of the grooves, the number of the hole structures at the corresponding positions of the edges of the grooves is larger than that of the hole structures at the corresponding positions of the middles of the grooves. Holes are reduced in the middle of the groove, the passivation effect is improved, and surface recombination of carriers is reduced; and meanwhile, the holes are additionally formed in the edges of the grooves, so that the carrier transmission capability is improved, and carrier transmission recombination is reduced. Therefore, the photoelectric conversion efficiency and the overall performance of the solar cell are improved together.