Welding tape: cost accounted for 6% of the component core auxiliary materials, demand continues to grow

From the type of application, welding tape is divided into interconnection welding tape and convergence welding tape, product segmentation is rich in variety. Interconnection welding tape is a solar cell conductive lead tape, used for series connection of the cell and collect and transmit the cell current. Interconnection welding tape is directly welded on the battery cell, the positive and negative poles of adjacent cells are connected to each other to form a series circuit, which will lead out the electricity converted from light energy on the battery cell, and at the same time play the role of heat dissipation and mechanical made of solar photovoltaic modules is one of the important components. According to the different types of components, interconnect tapes are divided into conventional interconnect tapes, MBB tapes, SMBB tapes, 0BB tapes, low-temperature tapes, shaped tapes and so on.

The interconnecting strips are used to connect the PV cell strings and junction boxes to transmit the PV cell string current. Cells are connected in series by means of interconnecting strips, and the converging strips connect the strings together to achieve the target voltage and complete circuit. Depending on the type of module they are applied to, converging ribbons are further divided into conventional converging ribbons, stacked wattage perforated ribbons, black ribbons, bending ribbons, stacked wattage ultra-thin ribbons, reflective ribbons, and so on. The consumption ratio of interconnecting welding tapes and converging welding tapes in conventional PV modules is about 4:1, the consumption ratio of interconnecting welding tapes and converging welding tapes in multi-grid modules is about 5:1, and stacked-watt modules do not need interconnecting welding tapes and only need to use converging welding tapes.

PV welding tape accounts for a relatively low cost in the module, but the quality of the tape has a greater impact on the efficiency, yield and service life of the module. Photovoltaic soldering tape consists of base material and surface coating: 1) the base material is different sizes of copper, the requirements of the specifications of the size of the precise, conductive properties, with a certain degree of strength; 2) the surface coating using electroplating, vacuum deposition, spraying or hot dip coating method and other special processes, such as tin alloys, and other coating materials in accordance with a certain proportion of the composition and thickness of the copper substrate uniformly coated on the surface of the copper substrate. Because the copper substrate itself does not have good welding performance, the main role of the tin alloy layer is to let the photovoltaic welding tape to meet the weldability, and the photovoltaic welding tape firmly welded to the main grid line of the battery cell, so as to play a good current conduction. According to the industry chain price measurement in March 2024, the current welding tape in the PV module cost accounted for about 6%, the cost share is relatively low. However, the quality of the welding tape has a greater impact on the efficiency and life of the module, the appearance of the PV welding tape size, mechanical properties, surface structure, resistivity and other performance indicators is an important factor affecting the fragmentation rate of the battery cell, power generation efficiency, and the long-term reliability and durability of the component, such as a reduction in the thickness of the welding tape will lead to an increase in the resistivity of the short-circuit current of the photovoltaic module and the output power is reduced; the quality of the welding tape does not meet the standards will lead to the risk of hidden cracks in the components The substandard quality of solder tape will lead to increased risk of hidden cracks in the module, increased risk of false soldering/over-soldering, and a decrease in the yield rate of the module. At present, the indicators of welding tapes that have a greater impact on the power and life of the module mainly include yield strength, concentricity, thickness of the tin layer, weldability, etc.: (1) Yield Strength: refers to the yield limit of the metal material when it is subjected to the yield phenomenon by the external force; an external force greater than the yield strength will make the metal material unable to recover from bending, which will lead to an increase in the risk of hidden cracking of the module, and a decrease in the component yield rate. (2) Concentricity: refers to the degree of offset of the inner diameter of the insert from the centre of the whole circle, i.e. the degree of offset between the centre of the copper wire and the centre of the welding tape; concentricity mainly depends on the uniformity of the coating thickness; the lower the concentricity of the welding tape is, the higher the risk of soldering during the welding process of the component, and the soldering component is prone to hot spot effect during power generation, which leads to the component being burnt and scrapped. (3) Tin layer thickness: refers to the thickness of the tin material coated on the outer layer of the copper material, i.e. the distance of the surface of the tin material from the copper material; if the thickness of the tin layer is too thin, the component is prone to false soldering, while the thickness of the tin layer is too thick, which may lead to hidden cracks in the component, and more seriously, may lead to debris. (4) Weldability: After soldering, the coating and the base material should be firmly combined without delamination, and there is no different colour at the welding place; poor weldability of soldering tape will lead to the phenomenon of false welding or over-welding of components during the welding process.

Economic support for PV demand continues to increase, driving the growth of welding tape demand

2023 PV module prices fell sharply after the PV system cost and LCOE fell significantly, even taking into account a higher proportion of the distribution of storage demand, or electricity prices fell, or a certain proportion of abandoned light, is expected to 2024 PV power generation project economics / return on investment will remain at a high level of attractiveness. At present, the global large-scale utility project potential demand is sufficient, with the end of the interest rate hike cycle, component prices bottomed out, the previous period due to the interest rate hike expectations, rapid price decline in components and wait-and-see demand is expected to continue to be released in 2024; at the same time, considering the major countries and regions due to low-carbon demand for the policy end of the good, it is expected that the demand for photovoltaic in 2024 will continue to have a strong growth momentum. We expect that in 2024 the global PV AC side of the new installed capacity year-on-year growth of 28% to about 520GWac (corresponding to the module demand of nearly 700GW): China is expected to maintain growth in the ultra-high base, but the growth rate or slightly lower than the global average, the overseas market will be more fully enjoy the dividends of the module price decline and the end of the interest rate hike (or even interest rate cuts to open), of which: the Middle East, Africa due to resource advantages, Low base, is expected to install high growth in 2024, the United States due to policy expectations and local supply increase is expected to install significant growth. Global photovoltaic installed capacity continues to grow, we expect 2024-2025 global photovoltaic new installed capacity 520/620GW, corresponding to the module demand 676/806GW, an increase of 28% / 19%, driven by the demand for photovoltaic welding tape high growth: component shipment structure, TOPCon technology route with a high price-performance ratio, equipment and process is more mature and so on the advantages of the first mass production With the accelerated release of TOPCon capacity, 2024-2025 TOPCon share is expected to rapidly increase to 70%/80%; HJT, xBC and other technologies are expected to gradually release with the cost, process advances, is expected to 2025, TOPCon / HJT / xBC shipments accounted for 80% / 8% / 7% respectively.

Welding tape product structure, it is expected that MBB, flat welding tape, low-temperature welding tape (including low-temperature 0BB welding tape) and PERC, xBC, HJT share is basically the same, TOPCon, HJT components in the 0BB share of the gradual increase is expected to gradually increase to 10% / 40% in 2024/2025, corresponding to the total share of 0BB welding tape in 2024/2025, 7.4% (of which the low temperature) 0BB welding tape 7.4% in 2024/2025 (of which low temperature 0BB welding tape 0.4%)/35.2% (of which low temperature 0BB welding tape 3.2%). Welding tape consumption, welding tape thin line lead to single GW component welding tape consumption decline, is expected to 2024 MBB welding tape / SMBB welding tape / flat wire welding tape / low temperature welding tape / 0BB welding tape single GW consumption fell slightly to 410 / 400 / 500 / 380 / 380 tonnes, but taking into account the thickness of the tape will lead to an increase in the resistivity of the welded tape thickness is expected to continue to decline in space is not large, 2025 Consumption will basically remain stable in 2025. In summary, it is expected that the global demand for welding tape in 2024-2025 273,000 tonnes / 322,000 tonnes, an increase of 24% / 18% year-on-year.

Multi-master grid / 0BB technology to promote welding tape wire diameter continues to decline, fine line to enhance the technical barriers

Review the development history of the photovoltaic welding tape industry, welding tape technology progress is mainly focused on improving its mechanical properties, as well as through the optimisation of the surface structure, the appearance of the size to match the battery technology route, reduce the resistivity of the welding tape, increase the total amount of light received by the battery sheet, in order to enhance the power of photovoltaic modules. Under the demand for cost reduction and efficiency improvement, the rapid development of cell multi-master grid and 0BB (no master grid) technology. For the cell, the finer the grid line is more conducive to reducing the amount of silver paste to reduce costs, while reducing the shading of the cell to enhance power generation efficiency, since 2010, the battery grid design towards increasing the number of main grids and reduce the width of the grid line in the direction of the development of multi-master grid technology from 2BB all the way to the development of MBB in recent years (9BB-15BB), there is now a MBB based on the development of the SMBB technology, no main gate technology, etc. In 2019, MBB technology is rapidly penetrating, and the market share below 9BB has dropped to 2% in 2022, and MBB technology has now become absolutely mainstream.SMBB (16BB and above) technology is an upgraded version of MBB, increasing the number of main grids to 16 and above, and at the same time of the increase in the main grids, it is coupled with a finer soldering tape to improve the precision of the string soldering, and to reduce the main grid PAD point area, not only can reduce the silver paste consumption, reduce costs, but also reduce the current transmission distance, reduce the grid line blocking, improve optical utilisation, effectively reduce the series resistance of the component, maximise the use of sunlight. At present, the number of SMBB main grids of mainstream manufacturers has increased to 16-20, according to CPIA, the proportion of 16BB and above SMBB technology in TOPCon cells in 2023 reached 87.5%, and it is expected to continue to improve in 2024. In order to further remove silver and reduce costs, the market R&D direction towards 0BB (no main grid) technology to promote, that is, the use of copper wire welding tape to replace the original silver main grid directly pooling fine grid current, and to achieve the interconnection between the cells. Compared with SMBB technology, 0BB technology has the following advantages: 1) directly saving the silver paste of the main grid, reducing the cost of silver paste; 2) using finer and more numerous welding ribbons for conductivity, which can enhance the conductivity and improve the CTM of the module; 3) adopting a low-temperature encapsulation process at the module end, which can carry thinner wafers; 4) as a result of adopting the design of dense multi-wire, which makes the contact point of fine wires and wires increase, the photogenerated carriers are collected greatly increased, which improves the ability of the module to resist hidden cracking, and improves the reliability and power generation of the module. According to the different ways of interconnecting the welding tape and the battery cell, the current masterless grid technology can be divided into SmartWire programme, welding+dispensing, and dispensing programme. the Smartwire route is to cover the whole side of the polymer film embedded with copper mesh on the battery cell after the production of the fine grid is completed; the welding+dispensing route is to weld the welding tape with the fine grid to form a string, and then to fix it with adhesive at the top and the bottom of the battery string; the dispensing route is to Since 2023, a number of domestic battery/module manufacturers have joined hands with equipment and auxiliary material manufacturers in the industry to invest in the research of gridless technology and started mass production and application: on 27 April 2023, Dongfang Risheng's 4GW of high-efficiency 25.5% heterojunction 0BB batteries passed through the entire line, and the first batch of heterojunction Fuxi batteries successfully rolled off the production line; in May 2023, Dongfang Risheng and Akcome Technology launched the first batch of heterojunction Fuxi cells with the adoption of the new technology of heterojunction 0BB. Sunrise and Akcome Technology launched HJT modules with 0BB technology with power as high as 741.456W and 730W respectively; in August 2023, together with Sunrise released the new N-type technology DAON3.0 high-efficiency BBF maingate-less modules equipped with TOPCon3.0 plus, marking the application of maingate-less technology in the direction of TOPCon.

In terms of equipment, the mass production of masterless grid process is also rapidly advancing: in September 2023, Maiwei shares signed a cooperation agreement with Anhui Huasheng new energy, the agreement contains the procurement of the first phase of 5.4GWNBB string welding equipment; Ningxia Maverick has a layout in dispensing, similar to the Smart Wire two solutions, which has been verified in the downstream customers; Suzhou Waterway and Shenzhen Guangyuan also have a layout in the 0BB equipment; On March 14, 2024, Waterway TOPCon 0BB welding process mass production release, can reduce the single piece of silver consumption ≥ 10%, enhance the component power ≥ 5 W. With the P-type batteries approaching the limit of efficiency, N-type batteries are gradually becoming the mainstream, of which the TOPCon technology route by virtue of the advantages of higher cost-effective, equipment and process is more mature, take the lead in large-scale mass production, into the promotion of the dividend period. With the successive release of new production capacity, it is expected that the market share of TOPCon battery in 2024 will be more than 60%, while HJT, xBC technology are also respectively in the cost side and process side breakthroughs, followed by the terminal market is expected to release volume. Compared with traditional PERC technology, TOPCon, HJT silver paste consumption is higher, according to CPIA, in 2023 PERC battery sheet positive silver consumption is reduced to about 59mg / piece, back silver consumption of about 25mg / piece, TOPCon battery double-sided silver paste (aluminium) (95% silver) average consumption of about 109mg / piece, heterogeneous junction battery double-sided low-temperature silver paste consumption of about 115mg/chip. Considering the current silver paste in the cell cost accounted for a relatively high, 0BB as a battery to reduce silver consumption of an important means, the future in TOPCon, HJT and other components have a large number of imported.

Fine grid to promote welding tape wire diameter decline, welding tape technology barriers continue to improve

With the development of multi-master grid technology, the battery fine grid line width continues to decline, according to CPIA, in 2023, the fine grid line width is generally around 23.5μm, with the improvement of paste technology and printing equipment precision, the fine grid width will still maintain a certain degree of decline, it is expected that the fine grid line width in 2030 down to about 18.0μm. In order to match the silver paste gate changes, welding tape products also towards the SMBB welding tape, 0BB welding tape and other direction iteration, interconnecting the average width of the welding tape from the 2BB era of 2mm down to the MBB era of 0.32mm, the current mainstream manufacturers of the SMBB main gate number has increased to 16-20, the welding tape wire diameter has gradually decreased to below 0.30mm. With the development of 0BB technology, supporting 0BB solder tape diameter is expected to further decline to below 0.20mm. Interconnect tape production mainly includes calendering, annealing, tin coating, wire four steps, convergence welding tape in the four links on the basis of an increase in the copper rod wire drawing link, the thick copper rod into fine copper wire. Welding tape fine line to improve the technical barriers to the production of welding tape. According to the "photovoltaic welding tape on photovoltaic module output power and aging reliability of the study", photovoltaic welding tape thickness reduction will lead to its related mechanical properties decrease, which leads to the welding tape tensile strength and yield strength continues to decrease; at the same time, fine line leads to the percentage of copper substrate gradually become smaller, copper substrate electrical resistivity than the coating alloy electrical resistivity is low, which leads to an increase in the resistivity of the welding tape. In addition, the decrease in the cross-sectional area of the PV welding tape leads to a decrease in the ability of the PV welding tape to collect current, which reduces the short-circuit current of the PV module; the welding effect between the PV welding tape and the main grid of the solar cell will also be poor due to the decrease in the cross-sectional area of the PV welding tape, which leads to an increase in the contact resistance and a decrease in the filler factor, and the decrease in the short-circuit current and the filler factor will ultimately lead to a decrease in the output power of the PV module. Therefore, the welding tape fine line on the performance requirements of the welding tape, tin coating thickness precision control, yield strength stability, concentricity improvement and other aspects of the requirements are increasingly high, the technical barriers to further enhance.

Diversified demand gives rise to differentiated products, the importance of multi-species R&D capability is highlighted

In recent years, the rapid growth of photovoltaic demand has given rise to the demand for diversified components, in addition to mainstream PERC, TOPCon components, for the differentiation of the market, HJT components, xBC components, black components, stacked modules and other products are also rapidly progressing, giving rise to the demand for HJT low-temperature welding tapes, xBC flat welding tapes, special convergence welding tapes, and other differentiated welding tapes, and the ability of welding tape companies to put forward a higher variety of R & D requirements. The following are the requirements for the R&D capability of welding tapes. (1) low-temperature welding tape: supporting the HJT route, the higher requirements of the solder formula: the current battery silver paste is divided into two categories of high-temperature silver paste and low-temperature silver paste, PERC, TOPCon, xBC and other technology routes using high-temperature silver paste, HJT batteries due to the structure of the amorphous silicon contains a more sensitive to the temperature of the thin layer, only the use of low-temperature silver paste, the welding tape also requires low-temperature welding. Low-temperature solder system is divided into indium-containing solder and bismuth-containing solder two categories, indium is a rare metal, reserves are small and the price of bismuth is about 30 times, so the current low-temperature solder to add bismuth-based, but the higher the bismuth content in the solder the worse the performance of the reliability, the need to improve the solder formula to enhance the corrosion resistance of the solder, soldering tape enterprise formula system puts forward a higher demand. 2) Flat solder tape: adaptable to the xBC battery single-sided welding Demand, welding tape equipment and process requirements to improve: xBC battery electrode is located on the back surface, the front side of the electrode without metal grid blocking, the effective light area is not the ultimate use of the demand, so the shape of the welding tape inclusive of relatively high, currently mainly used flat welding tape interconnection. The current xBC welding tape difficulties are: 1) technology and capacity: compared with round welding tape, flat welding tape in the tin coating step before the increase in the calendering process, the current industry to retain the flat welding tape technology, production capacity of a limited number of enterprises. 2) Battery welding from the double-sided welding into a single-sided welding, the need for a single-sided flat wire welding tape to achieve the positive and negative poles of the battery cells in series, however, the single-sided welding of the wafer is easy to be bent by the heat, the process is difficult to increase, so that the The link to the yield strength of the welding tape, layer uniformity, delay pressure and tin plating, etc. have put forward higher requirements. 3) Special convergence welding tape: to meet the diverse needs of the battery module aesthetics, reflective and so on. With the improvement of PV module product performance, special convergence welding tapes can meet the needs of battery components for welding tape aesthetics and reflective performance, and improve module power. Special bushing mainly includes black bushing and reflective bushing: (1) Black convergence welding tapes are suitable for all-black modules, covering the surface of the welding tapes with black coating to maintain the consistency of the appearance of the welding tapes, module frames and cells, which can help all-black photovoltaic modules to achieve more efficient automated production efficiency and better overall aesthetic performance, and reduce optical pollution. (2) Reflective convergence welding tape optimises the surface structure of the welding tape through the composite reflective film on the surface of the welding tape, the application of highly reflective coating on the surface, and the embossing of reflective patterns on the surface, so as to increase the total amount of light received by the battery by using the sunlight irradiated on the surface of the welding tape, and to further enhance the power of the photovoltaic module. In the future, with the development of the field of photovoltaic modules, black convergence welding tape and reflective convergence welding tape and other special convergence welding tape will further enhance the performance and reliability, and help the component side to improve product quality, in order to meet the diverse needs of downstream customers.

Welding tape industry characteristics: raw material costs accounted for a relatively high proportion of working capital accounted for a large

Cost structure: the cost of raw materials accounted for more than 90% of the cost of welding tape, raw material price fluctuations affect the level of profitability. Photovoltaic welding tape consists of copper base material and surface coating (tin alloy, etc.), photovoltaic welding tape production costs in the direct material accounted for a high proportion of the 2022 Yubang new material, Witten Electric direct material accounted for 94.4% / 94.2%. Direct materials are mainly copper, tin alloy, Yubang New Material 2021 cost composition, for example, the two accounted for 70.9%, 28.9%, so the fluctuations in raw material prices have a greater impact on the production cost of welding tape.

Business model: long sales account period + short procurement account period, large working capital consumption.

Photovoltaic welding tape industry downstream customers are mainly large photovoltaic module enterprises, a single customer is generally larger, usually using bank acceptance or commercial acceptance bill settlement, and has a certain account period. According to the prospectus of Tongxiang Technology, the credit period and settlement method signed between the Company and JinkoSolar is 90 days with monthly settlement, paying 70% of 6-month bank acceptance and 30% of 6-month commercial acceptance, and the sales payback cycle is long. Procurement, the main raw materials purchased by PV welding tape enterprises (copper, tin) are bulk commodities, with active trading market and trading prices, welding tape enterprises purchase orders on demand, raw material payment and settlement of shorter account period, the upstream suppliers usually provide the welding tape enterprises with an account period of about 1 month. Due to the short account period of upstream raw material procurement and the long account period of sales, the working capital of the welding band segment is occupied more. Comparison of photovoltaic industry chain head enterprise working capital turnover days, 2022 welding belt link (yubang new material, with the share of science and technology) working capital turnover days were 156 days, 93 days, higher than silicon wafers, components, glass, frame and so on, only lower than the working capital occupation is also larger film link (Foster, 214 days). According to the current price of welding tape, 10,000 tonnes of welding tape requires working capital of 200-440 million yuan. (Note: working capital turnover days = receivables + prepayments + inventory - payable - advance receipts). Welded belt industry working capital occupation is high, in the downstream demand for rapid growth in the background, a substantial expansion of production for the enterprise's capital situation put forward high requirements. The head of the enterprise actively expanding production, product accelerated iteration is expected to promote the concentration of enhancement. Welded tape industry raw material costs accounted for a high proportion of working capital accounted for a larger share of the enterprise capital strength and operating capacity puts forward higher requirements. 2023 since the second half of the photovoltaic industry as a whole financing tightened, small scale, cost control ability of the weak welded tape enterprise survival and expanding the pressure to increase, and at the same time consider the welded tape product iteration continues to improve the technological barriers between the enterprise of the support of the local government to obtain external resources as well as the ability of the difference in their own financial strength. Differences in their own financial strength caused by the research and development, production expansion capabilities of the gap will be magnified, the future has advanced technology research and development strength, with large-scale production capacity and financial advantages of the welding belt enterprises are expected to continue to enhance market share. In this context, yubang new material, with the share of science and technology, weiteng electric and other head of the welding belt enterprise actively expand production, is expected to further enhance the scale effect, consolidate the technical and cost advantages, photovoltaic welding belt market share is expected to gradually to the head of the concentration.