1614 results about "Battery bank" patented technology

The invention relates to the technical field of solar cell module packaging, in particular to a packaging structure for a perovskite-back contact crystalline silicon laminated solar cell and a preparation method of the packaging structure. The packaging structure comprises a front light conversion glass layer, a perovskite top cell layer, an infrared light-transmitting adhesive film layer, a back contact crystal silicon bottom cell layer, an adhesive film layer and a packaging bottom plate which are arranged in sequence, and butyl rubber surrounding the perovskite top cell layer, the infrared light-transmitting adhesive film layer, the back contact crystal silicon bottom cell layer and the adhesive film layer is arranged between the front light conversion glass layer and the packaging bottom plate, and the near infrared transmittance of 780 nm to 1100 nm in the infrared transparent adhesive film layer is 93% to 100%. According to the packaging structure based on the front light conversion glass layer and the infrared light-transmitting adhesive film layer, regulation and control of short-wave ultraviolet and near-infrared spectrums are considered, and the photoelectric property and reliability of the perovskite-crystalline silicon four-terminal laminated device are remarkably improved.

The invention is applicable to the field of photovoltaic technology, and provides a solar cell module and a photovoltaic system, the solar cell module comprises a first cell string, a first solder strip, a second solder strip, a bus bar and an insulating layer; the first battery string comprises a plurality of back contact battery pieces which are connected in series, and the back contact battery pieces comprise end battery pieces; a plurality of first welding strips and second welding strips are alternately arranged on the end battery piece in the first direction, the first welding strips and the second welding strips extend in the second direction, one end, close to the edge of the first battery string of the end battery piece, of each second welding strip extends to form a turnover section, and the turnover sections are turned over towards the end battery piece; the insulating layer and the bus bar are arranged in a stacked mode, extend in the first direction and are arranged between the second welding strip and the turnover section, the insulating layer makes contact with the second welding strip, and the bus bar makes contact with the turnover section. Therefore, welding personnel or equipment can accurately control welding, the welding quality is improved, meanwhile, thermal damage or subfissure to the back contact battery piece is avoided, and the service life and the stability of a product are guaranteed.

The invention discloses an intelligent energy storage method and system for a photovoltaic power station, and relates to the technical field of intelligent energy storage, and the method comprises the steps: collecting meteorological data, photovoltaic power station and geographic information data to construct a fusion data set, importing a photovoltaic prediction model, and outputting a photovoltaic prediction power sequence; the method comprises the following steps: acquiring time-of-use electricity price from a power transaction platform, receiving a power fluctuation limit value issued by a scheduling system, acquiring a charge state of a battery pack, namely an energy storage SOC state in real time, adopting a rolling time domain optimization solution model, solving a dual-target model, and outputting an optimal charge and discharge power instruction sequence; the energy storage unit submits an acceptable power range and a unit power quotation; a market clearing algorithm is executed; the quotation of the subject matter and the quotation of the energy storage unit are summarized; and after priority sorting according to prices and accumulative matching, issuing instructions are distributed according to a bid winning proportion, and the issuing instructions are distributed to the physical energy storage unit. And the whole life cycle cost minimization is realized.

The utility model is suitable for the field of photovoltaic technology, and provides a back contact battery assembly and a photovoltaic system, and the back contact battery assembly comprises a battery string which at least comprises a first battery piece and a second battery piece which are sequentially arranged along a first direction, the first battery piece is arranged at the end part of the battery string, and the second battery piece is arranged at the end part of the battery string. The first welding strip is arranged on the backlight surface of the first battery piece; the second welding strip is arranged on the backlight surface of the second battery piece; the first bus bar is arranged on the backlight face of the second battery piece, the first bus bar can be arranged on the backlight face of the battery piece in a hidden mode, the effective light receiving area of the battery assembly can be increased, the conversion efficiency of the assembly can be improved, and the overall attractiveness of the battery assembly is better; moreover, the first bus bar is arranged on the second battery piece, so that the first welding strip can be ensured to be fully attached to and welded to the effective welding position of the first battery piece.

A back-contact solar cell, a battery assembly and a photovoltaic system. In the back-contact solar cell, several grooves arranged at intervals are formed in a back surface of a silicon wafer, so as to divide the back surface of the silicon wafer into several first regions and second regions that are alternately arranged in sequence, in an arrangement direction of the first regions and the second regions, the silicon wafer is provided on the first regions and the edges of the grooves with extension portions that extrude to the upper side of the grooves, and second polarity doping layers are disposed on second tunneling layers in a stacked manner and have a preset distance with the edges of the grooves.

The invention relates to the technical field of solar cells, and particularly discloses a solar cell module and a photovoltaic system, and the solar cell module comprises a cell string which comprises an edge cell string; the edge confluence piece and the edge battery string are arranged on the edge of the same side of the battery assembly in the second direction, and the edge confluence piece is arranged in an extending mode in the second direction; the edge confluence welding strip is used for electrically connecting the edge battery string and the edge confluence piece, the edge confluence welding strip comprises a main body section and a bent section, the main body section is arranged in an extending mode in the first direction, and the bent section is arranged on the side, close to the edge confluence piece, of the main body section and on battery pieces in the edge battery string; one end close to the edge of the corresponding side of the battery assembly in the second direction is an edge end, and the bent section is bent in the direction far away from the edge end in the second direction. The hidden crack risk of the edge area of the battery assembly can be effectively reduced, the packaging effect is improved, and then the production yield and the long-term reliability of the battery assembly are improved.

The invention is applicable to the field of photovoltaic technology, and provides a battery piece, a battery assembly and a photovoltaic system, and the battery piece comprises a substrate which is provided with a first surface and a second surface which are oppositely arranged; the first thin grids and the second thin grids are arranged on the first surface, the polarities of the first thin grids and the polarities of the second thin grids are opposite, and the first thin grids and the second thin grids extend in the first direction and are arranged at intervals in the second direction. The winding plating structure can be used for conducting contact with the bus grid lines on the back faces of the adjacent battery pieces, a welding strip is not needed, carriers are in direct contact with the bus grid lines through the winding plating structure to form cross-battery transmission, and the transmission distance of the carriers is shortened.

The invention is suitable for the photovoltaic technical field, and provides a photovoltaic cell, a cell assembly and a photovoltaic system, the photovoltaic cell comprises a semiconductor substrate, a first polarity doping layer and a second polarity doping layer; the back surface of the semiconductor substrate comprises a plurality of doped regions, the doped regions comprise first regions and second regions, the first regions and the second regions are alternately arranged, the first regions and the second regions are connected through connecting regions, first polarity doped layers are stacked on the first regions, and second polarity doped layers are stacked on the second regions; the first polarity doping layer and the second polarity doping layer in at least part of the connection area are in composite contact to form a composite contact area; the absolute value of the difference between the reflectivity of the connection region and the reflectivity of the doped region is greater than 0.05%. Connection areas form composite contact, the problem of hot spots is solved, meanwhile, damage to the battery piece caused by additional machining is avoided, the production cost can be reduced, and meanwhile the recognition accuracy and efficiency of a machine vision system on the photovoltaic battery can be guaranteed.

In the field of photovoltaic power generation, a solar cell and a solar cell module capable of improving photoelectric conversion efficiency are provided. [Solution] The solar cell has a first surface and a second surface arranged back to back, and the first surface has first and second regions arranged alternately, and the second region includes a substrate having a groove formed in it relative to the first region, a passivation contact structure located in the first region, a passivation layer covering the surface of the passivation contact structure and the inner wall surface of the groove, and a first electrode located on the passivation layer and electrically connected to the passivation contact structure, and the side of the groove or the side of the passivation contact structure has a recess that is recessed inward along a first direction that is the direction from the second region to the first region, and the recess includes a continuous first side surface and a second side surface, the first side surface is connected to the first region, and the angle between the first side surface and the second side surface is a first obtuse angle.

The utility model is applicable 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, an insulating dielectric layer is arranged on at least partial region of a first doping layer, and at a preset position of a spacer region, a second doping layer is arranged on the insulating dielectric layer; the insulating dielectric layer is provided with an extension section which extends out of the first region and is at least partially bent towards one side where the silicon substrate is located, and the extension section, the first doping layer and the silicon substrate jointly form a deposition space. And at the first cross section along the first direction, the extension section, the first doping layer and the silicon substrate jointly form a closed pattern. The electric leakage doping part is arranged in the deposition space and forms electric leakage contact with the first doping layer. At the preset position, the second doping layer is provided with a first extension part which extends and covers at least partial area of the extension section, and the first extension part is in conductive contact with the electric leakage doping part. Therefore, the efficiency loss caused by electric leakage contact can be reduced while the hot spot resistance of the back contact battery is improved.

The utility model discloses a perovskite battery assembly, a photovoltaic assembly and electric equipment, and relates to the technical field of batteries. The perovskite battery assembly comprises a first substrate and a perovskite battery functional layer. The perovskite cell function layer comprises a first electrode layer, a perovskite light absorption layer and a second electrode layer. The first electrode layer comprises a first scribe line, the perovskite light-absorbing layer comprises a second scribe line group corresponding to the first scribe line, and the second scribe line group comprises a plurality of second scribe lines, the perovskite light-absorbing layer and a third scribe line of the second electrode layer. Since the second lineation group comprises a plurality of second lineation lines, the second electrode layer can be connected with the first electrode layer through the plurality of second lineation lines, and the area of the dead zone of the perovskite cell function layer can be reduced by designing the first part and the second part in the third lineation line. And the photoelectric conversion efficiency of the perovskite battery assembly is improved.

Disclosed in the present invention are a photovoltaic air conditioning system, and a control method and control apparatus therefor. The control method comprises: obtaining air conditioner load prediction result data on the basis of known air conditioner load data and an established air conditioner load prediction model; obtaining photovoltaic power generation prediction result data on the basis of known photovoltaic data and an established photovoltaic power generation prediction model; obtaining power grid load prediction result data on the basis of power grid data and an established power grid load prediction model; determining a first energy storage battery charging and discharging strategy on the basis of the air conditioner load prediction result data, the photovoltaic power generation prediction result data and the power grid load prediction result data; and determining a second energy storage battery charging and discharging strategy on the basis of the first energy storage battery charging and discharging strategy and a state-of-charge threshold adjustment strategy, and controlling the charging and discharging process of an energy storage battery assembly on the basis of the second energy storage battery charging and discharging strategy. The present invention can improve the efficient operation performance of a photovoltaic air conditioning system.

The invention discloses a perovskite solar cell module based on insulation layer protection and a packaging process optimization method thereof, through adding an insulation protection layer on the surface of a metal electrode layer and combining a specific deposition process and a packaging process, the risk of short circuit is effectively avoided, and the stability of the cell module is improved at the same time. The perovskite solar cell module sequentially comprises a glass substrate, a transparent conductive oxide layer, a first functional layer, a perovskite layer, a second functional layer, a metal electrode layer, an insulating layer, an adhesive film and a packaging cover plate from bottom to top, and efficient packaging is realized by optimizing laser scribing and insulating layer deposition processes. According to the invention, the long-term stability and the electrical performance of the perovskite assembly are obviously improved, and the perovskite assembly has a wide application prospect.

The invention discloses a solar cell, a cell module and a photovoltaic system. The solar cell comprises a silicon substrate, a plurality of first doped regions and a plurality of second doped regions, wherein the first doped regions and the second doped regions are arranged on the first side of the silicon substrate; the first doped region and the second doped region are sequentially arranged along the first direction and are arranged at an interval; an isolation groove is arranged between the adjacent first doped region and second doped region, and the isolation groove is used for isolating the first doped region and the second doped region; the isolation grooves comprise first isolation grooves and second isolation grooves, and the first isolation grooves and the second isolation grooves are sequentially arranged at intervals in the first direction; the width of the first isolation groove along the first direction is smaller than that of the second isolation groove along the first direction, and the vertical projection of at least one of two opposite side walls of the second isolation groove along the first direction on the silicon substrate comprises a first concave-convex structure. The risk of hidden crack of the cell can be reduced, the reliability of the cell is improved, and the photoelectric conversion efficiency of the cell is improved.

The invention discloses an emergency energy storage cabin with a multi-source power generation intelligent switching function and a power supply control method thereof, and relates to the field of emergency energy storage, and the energy storage cabin comprises a photovoltaic power generation device which is arranged at the top and can stretch and unfold a photovoltaic panel, a hydrogen energy storage power generation device connected with a bus, and an energy storage battery pack, in cooperation with the voltage and current sampling circuit and the illumination sensor, the controller controls switching among the power supplies according to acquired signals. The switching priority is photovoltaic power generation priority, the energy storage battery pack is subordinate, and the hydrogen energy storage power generation device is the last standby; the system is provided with a current limiting element, a pre-charging control unit and a graded load management function, and can cut off non-critical loads and supply critical loads in turns when a power supply is insufficient. The interior of the cabin can integrate water purification, hydrogen production, hydrogen storage and air conditioning modules. According to the method and the system, intelligent switching of multi-source energy, key load guarantee and continuous energy supply in an emergency environment are realized.

The invention relates to a new energy scene collaborative energy compensation system based on multi-energy complementation and a control method. The system comprises a power supply input and conversion module, an energy storage system, a power distribution and energy distribution module, a charging and battery replacement facility and a control system. The power input and conversion module is connected to an alternating current bus through a box-type substation, a photovoltaic panel and a photovoltaic inverter; the energy storage system is connected with an AC-DC bus through a power conversion system and a DC conversion module by utilizing an energy storage battery pack and a mobile power transmission vehicle; the power distribution and energy distribution module transmits electric energy through an AC-DC bus. The charging and battery replacing facility takes power from the AC / DC bus; the control system collects data and dispatches energy through a communication protocol, and cooperates with the power electronic transformer and the virtual synchronous machine control module to realize power grid frequency compensation and voltage stability control. According to the invention, by integrating photovoltaic, energy storage and charging facilities and power grid interaction capability, an intelligent scheduling mechanism is constructed, and multi-energy cooperative control and intelligent scheduling are realized.

The invention relates to the technical field of solar cells, and discloses a solar cell module and a photovoltaic system, and the solar cell module comprises a cell string, a bus bar and a welding strip. The battery string comprises a plurality of battery pieces which are connected in series, and the plurality of battery pieces comprise a first battery piece and a second battery piece which are sequentially arranged by taking a reference line as a starting point; the bus bar is arranged on the backlight surface of the second battery piece and located at the end close to the first battery piece, the orthographic projection of the bus bar covers the end, close to the second battery piece, of the first battery piece, and the length W of the bus bar in the first direction and the length L1 of the bus bar from the centering line of the first battery piece and the second battery piece to the edge of the bus bar meet the condition that L1 / W is larger than or equal to 0.2 and smaller than or equal to 0.8; the welding strip is arranged on the backlight surface of the first battery piece and is used for electrically connecting the first battery piece and the bus bar. The shielding area of the bus bar is distributed on the first battery piece and the second battery piece, so that the shielding area of the bus bar on the single battery piece is reduced, the double-sided rate can be improved, and the power loss is reduced.

The utility model relates to the technical field of solar cells, and provides an intermediate bus bar for a battery assembly, the battery assembly and a photovoltaic system, and a first end of a body part of the intermediate bus bar is connected with a first lead part which is bent towards a first side relative to the body part; the second lead part is bent relative to the first lead part so as to be stacked on the side, away from the body part, of the first lead part. One side of the second lead part is also provided with an extension part. Therefore, through the arrangement of the first lead part, the second lead part and the extension part, a lead structure formed by the first lead part and the second lead part cannot be located at the outermost edge of the middle bus bar, so that the risk of short circuit caused by lap joint of the lead structure and an adjacent circuit is reduced; and meanwhile, the edge end position of the middle bus bar is prevented from tilting in the manufacturing process, so that the welding reliability of the welding strip at the edge position and the middle bus bar is ensured.

The utility model is suitable for the field of photovoltaic technology, and provides a back contact battery assembly and a photovoltaic system, and the back contact battery assembly comprises a plurality of battery pieces; the plurality of welding strips are connected with two adjacent battery pieces; the insulating film is located on the side, away from the battery piece, of the welding strip, a plurality of exposed areas are formed on the insulating film, and the welding strip with the same polarity is exposed out of the exposed areas; the bus bar is arranged on the side, away from the battery piece, of the insulating film, the bus bar comprises a plurality of protruding structures and a plurality of connecting parts connected between the protruding structures, and the protruding structures extend into the corresponding exposed areas to be in conductive connection with the exposed welding strips. According to the invention, the current collection effect can be effectively improved while the bus bar is hidden, and in addition, due to the special design of the bus bar and the stable connection of the bus bar and the welding strip, the filling of a gap in an exposed region is facilitated, and the reliability of the battery assembly is improved.

The utility model relates to the technical field of solar cells, and particularly discloses a back contact cell assembly and a photovoltaic system, the cell assembly comprises a cell substrate, the back surface of the cell substrate is provided with a first grid line and a second grid line which are arranged in a staggered manner along a first direction and have opposite polarities; the confluence pieces comprise first confluence pieces and second confluence pieces, the first confluence pieces and the second confluence pieces are arranged in a staggered mode in the second direction, the first confluence pieces are electrically connected with the first grid lines, and the second confluence pieces are electrically connected with the second grid lines; the bus bar is electrically connected with the first bus member, and an insulating block is arranged between the bus bar and the second bus member; the insulating glue layer is arranged between the second grid line and the first bus piece, and in the second direction, the insulating glue layer comprises a first insulating part which continuously extends from the first bus piece to the direction of the adjacent second bus piece, and in the second direction, the insulating glue layer comprises a second insulating part which continuously extends from the second bus piece to the adjacent second bus piece; the sum of the distance from one end, away from the second bus piece, of the insulating block to the second bus piece and the width of the first insulating part is larger than the distance between the adjacent first bus piece and second bus piece. The reliability of the battery assembly can be improved, and meanwhile the production difficulty is reduced.

The invention is suitable for the technical field of solar cells, and provides a cell module and a photovoltaic system, and the cell module comprises a back contact cell which comprises a first polarity grid line and a second polarity grid line; the plurality of first welding strips and the plurality of second welding strips are respectively connected with the first polarity grid line and the second polarity grid line; the insulating strip is arranged on the sides, deviating from the back contact battery, of the first welding strip and the second welding strip, and the insulating strip comprises a through hole; the bus bar is arranged on the side, away from the back contact battery, of the insulating strip, the bus bar is electrically isolated from the first welding strip through the insulating strip, and the bus bar is electrically connected with the second welding strip through the through hole; wherein the insulating strip is a flexible insulating strip and comprises an open hole part and a non-open hole part, the through hole is located in the open hole part, and the thickness of the open hole part is larger than that of the non-open hole part. According to the flexible insulating strip, the thicker opening part is arranged in the flexible insulating strip, so that a buffering effect is achieved during welding and subsequent lamination, and the risk of subfissure and fragment is reduced.

The application belongs to the technical field of solar cells, and relates to an ultraviolet cutting adhesive film layer and a preparation method thereof, a perovskite solar cell module, a photovoltaic module and a photovoltaic system. The preparation method comprises the following steps: diluting ultraviolet curing adhesive by using an organic solvent to obtain an ultraviolet protection liquid; coating the ultraviolet protection liquid on one side surface of a light-entering surface of the perovskite solar cell module; and performing ultraviolet curing on the obtained ultraviolet protection wet film to obtain the ultraviolet cutting adhesive film layer. In the application, the diluted ultraviolet curing adhesive is used as a coating liquid and is coated on the light-entering surface of the perovskite solar cell module. The subsequent ultraviolet curing process can be performed at low temperature and low power, potential damage to a functional layer of the perovskite solar cell caused by preparation of the film layer under long-time high-temperature conditions is avoided, and thus the influence of the ultraviolet curing conditions on the module in the preparation process is effectively improved and the stability of the module under ultraviolet light in the operation process is enhanced.

The invention is suitable for the technical field of back contact cells, and provides a back contact cell, a preparation method thereof, a cell assembly and a photovoltaic system. The back contact cell comprises a silicon substrate, a first doping layer, a second doping layer and a first silicon material layer. The back surface of the silicon substrate comprises a plurality of first regions, a plurality of second regions and non-doped regions arranged between the first regions and the second regions; the first doped layer and the second doped layer are opposite in polarity and are respectively arranged in the first region and the second region; the first silicon material layer is arranged in the non-doped region; the non-doped region between the first region and the second region is used as the isolation region, and the isolation region does not need to be designed into a groove structure or a gap structure, so that the defects caused by the groove structure or the gap structure are avoided, and the leakage current of the back contact cell is reduced while the parasitic resistance of the back contact cell is reduced. Moreover, the light absorption efficiency of the back contact cell is improved, and the electrical performance of the back contact cell is optimized.

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; and the conductive bridging part is arranged at the avoiding area and is arranged between the bus bar and the welding strip exposing part, so that the bus bar is conductively connected with the welding strip exposing part 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.

Provided is an encapsulant sheet that has a preferable level of molding property and heat resistance as an encapsulant sheet for a solar cell module. [Solution] An encapsulant sheet for a solar cell module, which uses a polyolefin resin as the base resin, has a melting point of 55°C or higher and 120°C or lower, and the temperature difference between the extrapolated melting onset temperature and the melting point is 20°C or lower, and preferably has a gel fraction of 10% or lower, and the solar cell module has at least one of the front encapsulant layer and the back encapsulant layer constituted by the encapsulant sheet.

The invention is applicable to the technical field of solar cells, and provides a back contact cell, a cell module and a photovoltaic system, in the back contact cell, a first bonding pad, a third bonding pad, a first connecting grid line, a third connecting grid line and a first bus grid line are arranged on the back surface; the first connecting grid line is conductively connected with the first bonding pad and is connected with a first fine grid located between the first edge and the first bonding pad, the third connecting grid line is conductively connected with the third bonding pad and is connected with a second fine grid located between the first edge and the third bonding pad, and the second fine grid is disconnected at the first connecting grid line; and the first fine grid is disconnected at the third connecting grid line. The first bus grid line is arranged close to the third edge, the first bus grid line is at least connected with the second fine grid located between the first bonding pad closest to the third edge and the third edge, and the width of the first bus grid line is smaller than that of the first connecting grid line. Therefore, the efficiency of the back contact battery can be improved.

The utility model is suitable for the photovoltaic technology field, and provides a back contact cell, a cell assembly and a photovoltaic system, the back contact cell comprises a silicon substrate, and a first area, a spacing area and a second area are alternately arranged on the backlight surface of the silicon substrate along a first direction; the first tunneling layer is stacked in the first region; the first doping layer is stacked on the first tunneling layer; the second tunneling layer is stacked in the second region and a preset region of the interval region, and extends along the side wall, close to the first region, of the preset region to be in contact with one side, close to the second region in the first direction, of the first doping layer; the insulating medium layer is arranged on the first doping layer in a stacked mode, and the insulating medium layer is provided with an extending part extending to the interval area in the first direction in a preset area of the interval area; the second doped layer covers the first portion and the wrapping portion over the second tunneling layer. The efficiency loss caused by electric leakage contact can be reduced while the hot spot resistance of the back contact battery is improved.

The invention relates to an optical storage and charging system, in particular to an alternating current coupling-based optical storage and charging system, which comprises a high-voltage power distribution cabinet for receiving high-voltage electric energy of a power grid and distributing the high-voltage electric energy to a transformer; the transformer is used for converting the high-voltage electric energy into low-voltage electric energy so as to meet the voltage requirement of low-voltage side equipment; the low-voltage power distribution cabinet distributes low-voltage electric energy to the photovoltaic inverter, the energy storage converter, the charging pile and other loads; the photovoltaic inverter is used for converting direct current generated by the photovoltaic module into alternating current and enabling the alternating current to be connected in a grid or supplied to an alternating current load through a low-voltage power distribution cabinet, has a maximum power point tracking (MPPT) function and ensures that the photovoltaic module can output maximum power under different illumination conditions; the energy storage converter is used for controlling the charging and discharging processes of the energy storage module and adjusting the charging and discharging power and time of the energy storage module according to the instruction of the EMS energy management module; according to the invention, the defects of low energy utilization efficiency, poor system compatibility and insufficient economical efficiency of the lithium battery pack which cannot be combined can be overcome.

The invention relates to the field of photovoltaic module production, in particular to a bus bar welding method and welding equipment. According to the bus bar welding method, the bus bar is welded to the back contact battery pack, the back contact battery string group is placed on the glass plate, the bus bar is in lap joint with the welding strip exposed in the insulation area, welding is carried out, the back contact battery string group is located on the glass plate in the welding process, and the back contact battery string group does not need to be lifted in the welding process; relative friction between the welded battery piece and the glass plate is avoided, the welding quality is guaranteed, and the welding process is more simplified. The bus bar welding equipment provided by the invention is used for realizing the bus bar welding method, comprises a transmission positioning device, a bar manufacturing device and a welding device, and is simple in structure.

The present disclosure provides a solar cell, a module and a system. The solar cell comprises a silicon substrate, first doped layers, second doped layers, positive electrode grid lines, negative electrode grid lines and a first PAD portion. The second doped layers are in recombination contact with the first doped layers at predetermined positions, so as to form leakage recombination contact structures. A first PAD point and a second PAD point of the first PAD portion are electrically and respectively connected to at least one positive electrode grid line and at least one negative electrode grid line.