Patent Warfare Erupts in the Solar Industry: Jinko and Longi Engage in Global Legal Battles Over TOPCon Technology

The ongoing patent disputes between JinkoSolar and LONGi Green Energy are intensifying across multiple global locations, primarily involving TOPCon battery technology and component design and manufacturing. The competitive landscape in the photovoltaic (PV) sector is becoming increasingly heated.

Due to serious homogenization in TOPCon technology, prices have significantly dropped. While BC technology has advantages, its market penetration remains low due to factors such as cost and technical barriers. The ongoing patent litigation is impacting actual business activities within the PV industry, especially in overseas markets, potentially affecting the signing of new orders.

However, industry insiders assert that each technological route has its own strengths and weaknesses, and they are at different stages of development. Therefore, a blanket assessment is not feasible; PV companies should focus on breakthroughs in original technologies.

As the competition among PV technologies escalates, JinkoSolar (688223.SH) represents the TOPCon camp, while LONGi Green Energy (601012.SH) leads the BC camp in legal confrontations. In January 2025, JinkoSolar’s subsidiary, Xinyuan Yuedong Technology Development Co., Ltd., filed a lawsuit against LONGi Green Energy in the Intermediate People’s Court of Nanchang, Jiangxi Province, demanding an immediate halt to the infringement of relevant invention patents and compensation for economic losses. In the same month, Xinyuan Yuedong also initiated a patent infringement lawsuit against LONGi in the Tokyo District Court, Japan. Following this, in February, JinkoSolar filed a patent infringement lawsuit against LONGi in Australia and subsequently in Europe. Within two months, JinkoSolar launched four lawsuits against LONGi in various global locations, a pace that is relatively rare in the PV industry. LONGi Green Energy also retaliated by suing JinkoSolar for infringement in Jinan, Shandong Province, and the United States. The disputes primarily revolve around TOPCon battery technology and component design and manufacturing.

TOPCon is currently the preferred technology for most PV companies, boasting higher efficiency than the previous mainstream technology, PERC (Passivated Emitter and Rear Cell). However, it has not achieved a significant enough gap to create a barrier, leading to intense competition among existing players. BC technology, while also superior to PERC, faces challenges related to cost, technical barriers, and manufacturing processes, making it less mainstream for the time being. The competition in the PV industry is particularly fierce. The “latecomer” BC technology currently lacks numerous homogeneous competitors, and its advantages are increasingly recognized by customers, gradually encroaching on TOPCon’s market share.

As the landscape of the PV industry shifts, the technological competition has intensified, with numerous companies investing heavily in both technology routes. Both BC and TOPCon require a stronger market presence to secure their positions as dominant technologies. The essence of the ongoing patent litigation is a commercial war between companies, raising the question of whether there will be any winners from this widespread conflict.

Since PERC is no longer the mainstream technology, PV companies have sought to establish a strong competitive advantage by promoting a particular technology to become the mainstream choice. This strategy is straightforward, having been validated as feasible in the past. LONGi Green Energy, a seasoned player in the PV field, established a significant technological advantage through monocrystalline technology, enabling it to maintain its leading position for years and enjoy substantial commercial gains. As PERC began to decline, the relatively easy commercialization of TOPCon technology quickly gained traction. JinkoSolar, the early proponent of the TOPCon camp, undeniably benefited from this technological advantage. By 2019, JinkoSolar began constructing mass production lines for N-type TOPCon cells, becoming one of the first companies in the industry to produce N-type TOPCon cells and components.

According to information from 时代财经, by 2022, JinkoSolar had established multiple TOPCon cell factories with capacities exceeding 8GW, making it the first company in the industry to achieve large-scale production of TOPCon technology products. JinkoSolar’s Chairman and CEO, Li Xiande, noted in the company’s annual performance announcement for 2024 that it expects to reach capacities of 120GW for monocrystalline silicon wafers, 95GW for high-efficiency cells, and 130GW for components by the end of 2025.

However, the challenge with TOPCon lies in its low entry barriers; nearly all well-known companies in the industry have adopted this technology. According to incomplete statistics from 时代财经, notable PV companies such as JA Solar (002459.SZ), Trina Solar (688599.SH), Tongwei (600438.SH), Junda (002865.SZ), Zheneng New Energy, Canadian Solar (688472.SH), and Yida New Energy have all joined the TOPCon camp. Industry experts have indicated that the patents for TOPCon are relatively dispersed, meaning there are almost no technological barriers. For companies, the only option is to continually expand their scale to maintain their leading edge. Homogenization could severely affect the technology’s lifecycle, and since TOPCon is an extension of PERC, its efficiency improvements have already shown signs of surplus in the short term. According to InfoLink statistics, the cumulative shipment of TOPCon cells is expected to reach 109.3GW by 2024, accounting for 67% of total shipments. With its low barriers to entry, the homogenization of TOPCon has resulted in companies failing to enjoy significant product price advantages before prices collapsed. The price of TOPCon cells plummeted from 0.47 yuan/W at the beginning of 2024 to 0.28 yuan/W by the end of the year, a staggering drop of 40%. Currently, JinkoSolar has officially announced a cautious approach to capacity investment for 2025, stating that aside from upgrades to TOPCon technology, no new capacities will be added.

In contrast to TOPCon, fewer PV companies have chosen the higher entry barrier of BC for commercial mass production. According to 时代财经, the only large PV companies that have successfully commercialized BC technology so far are LONGi Green Energy and Aiko Solar (600732.SH). TCL Zhonghuan (002129.SZ) is expected to become the third company to achieve mass production using BC technology. During the International Solar Photovoltaic Exhibition in Japan this February, TCL Zhonghuan introduced its new BC module, which media reports suggest may achieve mass production by mid-year. However, renowned PV companies such as JinkoSolar, Tongwei, Junda, and JA Solar are also making strides in BC technology, while companies like Yingfa DeYao and Jinyang New Energy are beginning to invest in BC production capacity. In an announcement from last October, JinkoSolar mentioned that it has been increasing investment from a research and development perspective and has built a BC research and development production line, expressing confidence in its leading position in BC-related R&D and currently evaluating future capacity investment levels.

According to a report from Central Plains Securities, the issues surrounding industrialization, combined with the adjustment cycle in the PV sector, are putting pressure on product profitability, and the commercialization process of BC cells is progressing slowly. In terms of the advancements of major PV companies in the BC field, LONGi and Aiko lead in R&D progress, capacity, and shipments, while most other manufacturers are still in pilot production stages. Insights from 时代财经 reveal that market skepticism regarding BC technology mainly centers on two aspects: lengthy production processes and high investment costs. These two factors are interrelated, as the long processes and numerous steps lead to yield issues, keeping investment costs high. Zhang Yingbin, head of strategic products and markets at Trina Solar, publicly stated that the renovation cost for TOPCon cells is about 30 to 40 million yuan per GW, while the investment cost for BC cells is between 250 to 300 million yuan per GW. Previous analyses have suggested that in the early stages of new technology iterations, leading companies possess the financial strength, scale, and cost advantages necessary to bear initial large-scale R&D investments and early-stage losses, while subsequent second- and third-tier enterprises can follow suit.

Among the customer base, distinctions in technology choice are beginning to emerge. According to TrendForce statistics from China’s PV industry tendering database, the total tendering volume for PV modules in 2024 is approximately 297GW, with 15.7GW explicitly designated for HJT (Heterojunction)/BC projects (including about 12.6GW for HJT and 1.15GW for BC, plus another 1.5GW for either HJT or BC). This represents a substantial increase compared to 2023. Major state-owned power generation groups, such as China Huaneng, Yue Shui Dian, China Huadian, and State Power Investment Corporation, have made explicit purchases of BC cell products in their tenders, particularly with China Huaneng separately designating a segment for BC components during the tendering process in September 2024. Aiko Solar indicated to 时代财经 that while TOPCon currently has the highest penetration rate, as more customers recognize the advantages of BC technology, the capacity for BC (primarily from Aiko and LONGi) is expected to exceed 70GW by the end of 2025, accounting for 10% to 15% of the anticipated global installed capacity, showing significant improvement from the single-digit penetration rate in 2024. LONGi Green Energy’s Chairman, Zhong Baoshan, also mentioned in an investor communication last year that he expects the silver usage issue to be resolved in the second half of 2025, and that by the end of 2025, the cost of BC components will be on par with or lower than that of TOPCon.

Nonetheless, JinkoSolar noted in a research announcement that it anticipates TOPCon technology to remain mainstream for the next 3 to 5 years. The company believes that after the introduction of its invisible busbar technology, the efficiency gap between TOPCon and BC will narrow, while TOPCon’s production costs will offer advantages, allowing it to maintain its overall lead.

The current litigation among industry giants primarily focuses on TOPCon battery technology and related component design and manufacturing. According to an industry insider familiar with patent lawsuits, the origin of these disputes traces back to LG’s sale of 745 photovoltaic patents in 2022, covering countries and regions including the United States, South Korea, Germany, China, Australia, and Europe, all of which are invention patents. Reports indicate that JinkoSolar acquired 294 patents from LG in the United States, 168 in South Korea, 166 in Germany, 114 in China, 2 in Australia, and 1 from the European Patent Office. Following the acquisition, JinkoSolar transferred 192 patents to Trina Solar between March and April 2024 and 131 patents to JA Solar between May and June 2024, thereby forming a patent alliance in the TOPCon camp.

According to the aforementioned industry insider, after acquiring a substantial number of patents, JinkoSolar communicated with JA Solar, Trina Solar, and LONGi, expressing a desire for LONGi to share the costs of patent acquisition. However, JinkoSolar’s demands were perceived as excessively stringent, requiring not only payment from LONGi but also the opening of BC patent licenses. Regarding the patent litigation issues, 时代财经 contacted both JinkoSolar and LONGi Green Energy. JinkoSolar did not confirm the information, while a representative from LONGi stated that the patent battle is fundamentally a product of deepening industry “involution.” While it may temporarily solidify their market position, such actions could ultimately weaken China’s global technological leadership in the PV sector. If the industry becomes mired in a “patent arms race,” rather than focusing on breakthroughs in original technologies, it could lead to a depletion of innovation, a rigidification of technological pathways, and a passive stance in international competition.

Despite the lack of confirmation regarding the origins of the patent litigation, the battle has already begun. Companies within the “Jingjing Tianlong” alliance, including JA Solar and Trina Solar, are engaged in patent disputes with various enterprises. Many companies involved in these litigations have maintained silence when approached by 时代财经. Notably, during the outreach, it became apparent that the concept of “patent wars” is being downplayed, with “protecting one’s intellectual property” emerging as the new expression for patent litigation.

From a public relations perspective, both JinkoSolar and LONGi Green Energy are actively promoting their narratives to suppress the other’s voice and secure advantageous positions. However, the uncertainty surrounding the duration of patent litigation casts a shadow over the future development of the PV industry. According to Meng Bo, a lawyer at Beijing Jingshi Law Firm, the impact of patent litigation on companies must be assessed based on the significance of the involved technologies, including whether they are critical and the results of court rulings. Typically, civil lawsuits conclude after first and second trials, but intellectual property cases may face challenges regarding the validity of the rights involved, leading to administrative litigation over patent validity. In judicial practice, the duration of cases depends on the litigation strategies of both parties.

For practitioners, the core of patent litigation lies in the battle for market voice, which affects a company’s commercial profitability. As Qi Haishen, CEO of Jincheng Technology, stated, “The patent war is a form of game theory.” JinkoSolar is arguably the largest beneficiary of TOPCon technology. The confrontation between TOPCon and BC fundamentally represents a contest of technological routes. This shift from a competition of production capacity to a competition of products—essentially a battle of technology routes and ecological camps—is evident. Liu Jimao, founder of Hongda Photovoltaic, commented that the patent war mainly focuses on core technologies such as TOPCon battery technology and component design and manufacturing. Generally, patent infringement cases take about 12 to 18 months from filing to final ruling (including appeals), while complex cases may take 2 to 3 years or longer. Therefore, the patent war has minimal immediate impact on the industry and application end.

He believes that the primary goal of the patent disputes among leading PV companies is to seize the definition and market voice of technology. Through patent litigation, some PV companies are attempting to strengthen patent protections to accelerate industry cleansing, especially in overseas markets that prioritize patents, in order to prevent excessive internal competition. However, this round of patent warfare may not only fail to weaken competitors but may also not assist in resolving the contest between TOPCon and BC. Historical precedents suggest that this round of patent wars is likely to end in reconciliation.

Nevertheless, some industry insiders have indicated that the escalating patent wars do affect actual business, particularly in overseas markets. “Some large companies involved in investment projects, international investments, and funding sources are indeed concerned about patent protections, especially in the U.S. and European markets, which can slightly impact new order placements. However, if it’s related to modules, it typically doesn’t involve patent issues. The potential influence of patent disputes, however, can be significant.”

In conclusion, amid the patent wars, there are no winners. The four leading companies in the PV industry, known as “Jingjing Tianlong,” have all faced substantial losses. Finding a way out of this downturn is the only choice for PV companies. Recent announcements reveal that in 2024, JinkoSolar reported a net loss of 1.012 billion yuan, a decrease of 114.66% year-on-year. JA Solar expects a net loss ranging from 4.16 billion to 4.86 billion yuan, while Trina Solar reported a net loss of 5.199 billion yuan, reflecting a year-on-year increase of 190.35%. LONGi Green Energy anticipates a net loss of between 8.3 billion to 8.9 billion yuan. Some industry insiders have pointed out that the high degree of homogenization in TOPCon products has led to intense competition during this mismatch of supply and demand. TOPCon manufacturers are leveraging patents to capture sales shares and reinforce their market positions. In contrast, BC technology, characterized by a high degree of differentiation, has seen steady growth in sales and market penetration as relevant companies develop strong patent protections.

However, it is important to note that each technology route has its own advantages and disadvantages, and they are at different stages of development, making it unwise to generalize.