Wen Xiaotian

the photovoltaic sector, which has been silent for a long time, has returned to the spotlight of the capital market because of the words of Zhong Baoshen, chairman of Longji Green Energy (601012.SH).

"Longji already has a very clear view that in the next 5-6 years, BC cells will be the absolute mainstream of crystalline silicon cells, including double-sided and single-sided cells." At the recent performance meeting, Zhong Baoshen said in response to the choice of battery technology that Longji's next planned investment projects will all adopt BC technology.

For a long time, Longji, as a photovoltaic giant, has not made a clear statement on the choice of photovoltaic cell route in the future. This is because in the past two years, as the efficiency of P-type batteries approaches the limit, N-type technologies have come to the fore, mainly including TOPCon, heterojunction (HJT), BC technology, etc. In contrast, the industrialization of TOPCon and HJT is more heated, and the industrialization process of TOPCon is faster, with a large number of new capacity bets on TOPCon technology.

But Longi always believes that TOPCon batteries are "transitional products" and is also cautious about expansion. For this reason, Longji hopes to find a more advanced and differentiated product with a longer life cycle in technology.

But investors aren't buying it. Some believe that although TOPCon does not represent the future technology, it can bring stable income and profitability to the enterprise before the breakthrough of existing technology is achieved. Choosing to skip TOPCon battery technology directly is an excuse Longji is making for his strategic misjudgment.

This has directly led to its depressed stock price since last year, which has confirmed its lonely status as an "outlier.

This time Longji has high hopes for BC batteries. Not only did he choose the current "non-mainstream technology", he also denied the future trend of TOPCon. Zhong Baoshen concluded, "The emergence of BC batteries will gradually replace TOPCon."

as soon as this remark was made, the relevant target companies rose sharply, including Guangxin Materials (300537.SZ), Yonghe Zhikong (002795.SZ), Deer Laser (300776.SZ), Inno Laser (301021.SZ), Aixu shares (600732.SH), etc. all rose to varying degrees.

but interestingly, Longji itself only reaped a 4% increase on the day of the performance briefing, with the highest share price of 28.38 yuan/share. as of September 11, the closing price of 26.66 yuan/share had fallen by 6%.

then, why did longji green energy, whose technical route has always been clouded, choose BC battery? In Longji, where TOPCon lags behind the pace of its peers, what does BC battery mean to Longji? Abandoning the consensus in the industry and finding another way, can Longji return to the throne with BC battery?

BC battery is the "crown jewel"

"BC battery is the 'crown jewel '." At the performance presentation meeting, Zhong Baoshen did not hesitate to praise BC batteries. He said that BC batteries have excellent power generation performance and the industry is ready to pick this "pearl" and BC batteries will really go to the market.

Although LONGi's meeting made more investors understand the concept of BC battery, in fact it is not a new thing.

BC battery (back contact) is called back contact battery, and its base type is IBC battery (interdigital back contact battery). Unlike TOPCon and HJT, which improve conversion efficiency by reducing electrical losses, IBC cells reduce optical losses to improve conversion efficiency by adding structures such as anti-reflection layers and light trapping layers.

IBC structure, source: "High efficiency n-type Si solar cell technology status and development trend"

Therefore, the BC battery can maximize the use of incident light, bring more effective power generation area, thereby improving the battery energy conversion efficiency, and the appearance is beautiful, and the advantages of distributed photovoltaics are more prominent.

At the same time, it is a platform structure that can be combined with multiple routes. It can be combined with P-type, HJT, TOPCon and other technologies to form HPBC, HBC (compatible with part of HJT process), TBC and other technical routes (compatible with part of TOPCon process).

For example, the superposition with TOPCon technology is called TBC cell, while the superposition with HJT technology is called HBC cell. These batteries are collectively referred to as class BC batteries.

In the photovoltaic industry, improving conversion efficiency has always been the core of photovoltaic technology competition and the foundation of winning the future.

Over the past few years, both single-crystal and multi-crystal batteries have maintained efficiency improvements of 0.3-0.4 per year. But today, once the P-type battery for the market mainstream photovoltaic cell technology, the average mass production conversion efficiency of about 23.5, has approached the efficiency limit.

N-type battery efficiency improvement potential, investment costs continue to reduce, the head of photovoltaic enterprises have this round of photovoltaic technology change from the P-type battery to the N-type battery.

in the n-type battery technology route, TOPCon battery can be compatible with the manufacturing process of the previous generation of PERC battery technology, and can be upgraded based on the PERC production line, greatly reducing the investment cost and depreciation cost of the equipment, which helps TOPCon to take the lead in this round of n-type wave.

at present, key manufacturers including jingao, jingke, zhengtai, dongfang sunrise, tianhe, a new energy, xiexin integration, junda shares, yijing photoelectric, hengdian dongci, sunshine energy and other key manufacturers basically choose TOPCon as a technical route. In the first half of this year alone, domestic enterprises announced that the amount of investment in TOPCon batteries and components was as high as more than 230 billion yuan.

however, although the investment in TOPCon battery is very hot at present, the average conversion efficiency of n-type TOPCon battery is 24.5, and the improvement efficiency is very limited.

this is also the reason why longji is technically bearish on TOPCon. in the view of longji management, compared with traditional PERC batteries, TOPCon's efficiency improvement is too small, its industry technology is highly homogeneous, and it is easy to have surplus without making money. now there are such signs.

In contrast to BC batteries, the average conversion efficiency of XBC batteries has reached 24.5. In the future, with the development of TBC, HBC and other battery technologies, the conversion efficiency can be further improved.

to sum up, it is not difficult to understand the reason why longji green energy chose BC battery. just like PERC replaced BSF (aluminum back field battery) in those days, TOPCon is now similar to PERC in 2018 and 2019. BC battery has full stamina in performance and is likely to replace TOPCon. As Longji said, "BC cells with high conversion efficiency will be the jewel of the crystalline silicon battery industry."

misjudgment and embarrassment of "worshippers"

The conversion efficiency of photovoltaic cells is the most critical yardstick for each iteration of photovoltaic technology. As a "worshipper" in the photovoltaic industry, Longji has always been the ultimate pursuit of photoelectric conversion efficiency.

Take the P-type battery as an example. From 2017 to the present, the efficiency of PERC batteries has increased from about 20.5 percent to about 23.5 percent now.

don't underestimate the 3% improvement efficiency. the most important thing in the photovoltaic industry is to reduce the cost. there are mainly two ways to reduce the cost. one is to reduce the amount by thinning silicon wafers and reducing the use of silver paste. the other is to increase the processing cost by improving the battery efficiency and reduce the processing cost of all other parts, which is an increment.

specifically, on the basis of 20%, every one percentage point increase in conversion efficiency can save more than 5% of the cost for downstream power stations, with great results. Therefore, for higher conversion efficiency, even if it is only increased by 0.01, it is also a "battleground" for photovoltaic companies ".

put Longji on the abscissa of photovoltaic development, there is a figure behind almost every refresh of efficiency. the world record for the conversion efficiency of PERC batteries, which is the mainstream in the photovoltaic industry, is 24.05 for Longji green energy, which is very close to the laboratory efficiency limit of 24.5 for ISFH (Hamelin solar research institute, Germany).

It can be said that Longji has brought the production efficiency of PERC batteries to the theoretical limit, and has also made photovoltaics move towards the era of affordable Internet access, becoming the most economical technology in the photovoltaic power generation industry.

This is the fundamental reason why Longji is the most successful and largest photovoltaic module enterprise in the P-type era.

Until 2022, N-type batteries will explode, and the development of next-generation photovoltaic cell technologies such as TOPCon, HJT and IBC will be in full swing. Compared with traditional P-type batteries, although these N-type batteries have complex manufacturing processes and higher costs, they have the advantages of high conversion efficiency, high double-sided rate, and low temperature coefficient. They are generally regarded as the next-generation battery technology by the industry.

Among these options, who can stand out and replace PERC as the mainstream? Longji did not hesitate to choose HJT and IBC technologies with higher photoelectric conversion efficiency.

take HJT technology as an example. at the 16th China new energy international exposition and summit forum last year, longji announced that it had received the certification report of ISFH. the conversion efficiency of silicon heterojunction cell independently developed by longji reached 26.81.

Martin Green, the father of solar energy in the world, said that this is the highest efficiency record of silicon-based solar cells in the world. It is also the latest world record in five years since the Japanese company set a record of 26.7 per cent in 2017.

Not surprisingly, Longji will once again lead the third revolution in photovoltaic cell technology.

but there was no accident. one variable disrupted all the scheduled rhythms of longji, that is, the surging demand side market-

Since last year, the energy crisis caused by the war between Russia and Ukraine has caused European countries to put energy security on the agenda, and the supply of new energy represented by photovoltaic is in short supply; on the other hand, the domestic policy of new energy policy has been introduced frequently, which has intensified the popularization of photovoltaic energy.

this background also coincides with the node of technological change of photovoltaic cells. in the uncertain period of many enterprises, a head enterprise jingke energy (688223.SH) chose to take the lead, firmly optimistic about TOPCon technology, and quickly entered the mass production stage.

at the beginning of last year, the 16GW large-size n-type TOPCon capacity invested by jingke energy in the first phase reached full capacity. based on the successful experience of the first phase, jingke continued to invest heavily in the second phase of n-type TOPCon capacity with higher efficiency and better cost.

jingke, which has achieved good transformation results, made those hesitant manufacturers finally determined to enter the TOPCon camp. then everyone swarmed to bet on TOPCon, and then TOPCon quickly became the mainstream. According to InfoLink estimates, by the end of 2023, TOPCon's nominal capacity will increase to nearly 500GW, which is also the origin of the current photovoltaic overcapacity.

In daily life, a product being chosen by more people often means that the product is good. But in today's PV industry, it's the exact opposite.

As mentioned earlier, TOPCon can be chosen by more manufacturers not because of better photoelectric conversion efficiency, but because of its high compatibility with PERC production lines, close staff quality and low equipment investment cost, it is chosen in large numbers. And once the cost effect of mass production, the advantages of HJT technology are directly buried.

After all, HJT's technology popularization must also go through a process of large-scale efficiency improvement and cost reduction before it can be successfully pushed into the market. But now it seems that although HJT has an unparalleled competitive advantage, the TOPCon camp is increasingly lined with giants.

When a market is dominated by irrationality, the rational is naturally excluded.

under such an industry background, longji, the industry leader known as "photovoltaic Mao", is very passive, but has always claimed to have a layout for a variety of technical routes.

At the same time, the capital markets are "squinting at it". In the photovoltaic industry overcapacity theory is rampant, reshuffle or will be reopened node, this year new energy photovoltaic-related enterprises share prices have fallen, Longji's own share price from the beginning of the year so far has fallen by nearly 40%, and the historical high than down more than 60%, market value evaporation of nearly 300 billion yuan.

in February this year, Longji, under pressure, had to announce that a 30GW line in Erdos would be adopted by TOPCon.

Li Zhenguo, president of Longji Green Energy, explained to the outside world during the SNEC photovoltaic exhibition in the first half of the year, "TOPCon was chosen to meet the needs of customers. Although Longji is not satisfied with TOPCon technology. Before the better technology is mature, Longji cannot completely stop and do nothing."

but seven months later, longji still can't get through this threshold in his heart.

at the recent performance presentation meeting, Zhong Baoshen put forward a comprehensive bet on BC battery technology and announced a series of new production capacity that all adopt BC battery technology routes. Industry analysts, this means that Longji's BC battery will gradually increase volume, while limiting TOPCon expansion.

In the darkest moment, "go your own way"

From Longji's point of view, working hard on BC batteries may seem unexpected, but it is also reasonable. However, from the perspective of industry pessimists, Longji's choice of BC route is not sexy.

In the case of technologies such as BC batteries alone, they are not monolithic.

at present, BC structure is divided into three major routes: one is the classic IBC cell process represented by SunPower, an American solar energy company; One is HBC process represented by KANEKA of bell chemical co., ltd. There is also a POLO-IBC process represented by ISFH of Merlin solar energy research institute.

among them, SunPower is the pioneer of IBC battery and has rich patent reserves. in 2019, the SunPower will be divided into two parts, and the newly established Maxeon Solar(MAX N.O) will undertake the manufacturing business of original solar battery and focus on IBC battery structure.

Global shipments of Class BC batteries exceed 1GW in 2022, mainly from contributions from Maxeon Solar. At present, TCL Central (002129.SZ) holds about 27% of Maxeon and is its largest shareholder.

Back home, Aixu, which used ABC components, was firmly in the top spot in BC components before Longji. The latter uses the POLO-IBC process of ISFH, namely TBC mentioned above, which combines the advantages of IBC and TOPCon.

Longji's HPBC technology, all called hybrid passivation back contact, is a battery technology that combines PERC and IBC on a p-type silicon wafer substrate.

"Aixu and Longji's two BC technologies have their own characteristics." Some industry insiders commented. "In terms of efficiency, Asahi may be higher, and the cost may be better.

At present, the domestic listed companies with BC molding capacity only have ABC batteries and components of Aixu shares and HPBC batteries of Longji Green Energy. In addition, the production capacity of other companies is planned or under construction.

according to the Pacific research institute, in terms of XBC battery capacity, Longji is expected to ship 30GW in 2024 and aixu is expected to ship more than 20GW.

In other words, the BC battery is still in the niche stage. Under Longji's leading effect, it is still unknown whether BC batteries can be transferred from the minority to the masses.

because the photovoltaic industry is not at that time, the technical route is scattered from one point to another, and it is easy to blossom at multiple points. But it is not so simple to return to one place from a hundred flowers blooming.

Take the current overcapacity of the photovoltaic market, this is a typical buyer's market, the domestic power station holds the initiative. From an economic point of view, domestic power stations will undoubtedly choose a more cost-effective solution.

and if the industry ecology is not established, only a few mass-produced BC batteries such as Longji will be difficult to catch up with TOPCon batteries in terms of capacity expansion, and BC batteries will be difficult to become mainstream for a long time.

More importantly, the bearers believe that there is still a certain "selfishness" in Longji's choice of BC battery ".

According to the current layout of various enterprises, Longji Green Energy has lost its first opportunity on the TOPCon and heterojunction routes and can only be a "follower". The most realistic reason for choosing BC technology today is that HPBC can digest excess P-type silicon wafer capacity and actively ship it. Second, there is still dependence on the P-type path.

in the last round of industry reshuffle, longji green energy became the world's leader in components and silicon chips by betting and insisting on the single crystal route in advance. But in this round of technological change, Longji's "too cautious" and "choice phobia" have greatly reduced the impression of many industry insiders and investors, which directly triggered a completely outdated speculation.

However, long-term activists are optimistic about Longi's high-profile choice of BC battery technology this time around.

From Longji's point of view, the "anti-market" behavior of the industry's concentrated position TOPCon capacity has become a fact. Instead of competing for a market full of competitors in the past, it is better to seize the first-mover advantage of the new technology route. This is a more pragmatic idea.

according to the carding, longji's research and development of BC technology is not decided at the moment. As early as 2018, Longji focused on HPBC technology. Under the leadership of Dr. Li Hua, Longji's chief scientist, HPBC was put into mass production for four years this year.

on November 2 last year, longji held a grand six-city synchronous conference, released its new generation of photovoltaic module product Hi-MO6 in a high profile, and stressed the importance of HPBC technology used in the product, saying that the research and development cost of the technology exceeded 1 billion yuan, which was the most efficient mass production product at that time.

As a result, BC battery technology has joined the first echelon of the third-generation technology route. In this process, Longji has invested a lot of energy and funds to independently develop new equipment and new materials, including new welding technology. According to Chairman Zhong Baoshen, all aspects of HPBC are innovative.

according to zhong baoshen's statement when facing investors' questions, longji's choice is based on a large number of test data. among the pilot line running data of the three third generation technologies, BC has strong competitiveness, excellent power generation performance, large space for cost reduction and efficiency improvement, and its differentiated characteristics are also in line with the general trend of photovoltaic development in the future and have a long life cycle.

At the same time, after previous accumulation, Longji's product line has now passed the most difficult climbing stage, and the production capacity has reachedThe company expects to reach the level of 25GW annual production capacity by the end of this year.

In other words, BC has an advantage in the third generation, while Longji has an advantage in BC. This is the confidence of Longji's high-profile announcement of the new technology of "full warehouse" at this time.

It is undeniable that this company is going through the "darkest moment in history, and doubts from the outside world are also pouring in.

However, in many drastic changes in the industry, the core competitiveness of Longji's core concept, strategic layout, technology choice, R & D investment, investment pace, management improvement and many other elements has not changed.

from the perspective of the development of photovoltaic technology in the future, it will be divided into at least two directions. ground power stations will measure the leading nature of technology completely by the cost of electricity. Distributed photovoltaic has more considerations, including the cost of electricity, safety, integration with buildings, and convenience of maintenance after combining with scenes.

in the short term, the current hot TOPCon technology is not entirely based on these two directions, but in the long run, when the buyer's market tends to be rational, the photovoltaic industry will return to the right path, and the BC battery technology that Longji has been updating may be the "key" to deal with the development of green energy in the future ".

On many occasions, Li Zhenguo also emphasized more than once that Longji is the company with the clearest technical route in the industry in terms of the depth of research and essential understanding of various routes. This is also the fundamental reason why it firmly chooses BC battery technology from the strategic level.

photovoltaic battlefield, ups and downs, but the technology for the king never out of date, every change in technology will reshape the war situation.

the era when longji ruled single crystal PERC by silicon wafer components has passed. the wave of n-type technology is surging, and the rising stars are surrounded by wolves. although the former king stood high and looked far away, he did need to fight hard to usher in the future.