LONGi releases “Technical Brief” for its new Hi-MO 5 module for ultra-large power plants

Global News

On June 29, 2020, LONGi, a global leading solar technology company headquartered in Xi'an, China, released a Technical Brief” of its recently announced Hi-MO 5 - an ultra-high power module designed for applications in utility-scale power plants - with front-side power up to 540W, 21%+ efficiency and module size of 2256×1133mm.

The Technical Brief gives an in-depth look at the technologies behind the innovations of the Hi-MO 5 module.

Gallium-doped wafers and proprietary “Smart Soldering” technology bring higher performance

In 2020, LONGi and Shin-Etsu Chemical entered into a global patent agreement on gallium-doped technologies, which allows applications of LONGi’s products with gallium-doped technologies.

LONGi’s R&D team has optimized the gallium-doped M10 standard silicon wafers (182mm) to produce a P-Type Mono PERC module with the lowest LID. Gallium-doped silicon wafers have been verified to show lower LID performance with stable, long-term power generation when compared to boron-doped ones. Though gallium-doped silicon wafers are more expensive, LONGi has effectively addressed this with advances in technology and production scale.

With the gallium-doped cells, Hi-MO 5 has increased attenuation performance, power performance and long-term reliability. The 1st year power warranty is an industry-leading 98% and linear annual attenuation is within 0.45%.

LONGi also adopts “Smart Soldering” technology on Hi-MO 5 which increased module conversion efficiency by 0.3%. This proprietary technology uses integrated segmented soldering ribbons that maximize light capture and reliably connect cells with reduced gap distance. “Smart Soldering” reduces the tensile stress of the cell for higher reliability.

Shaping the future, LONGi delivers true value to global partners and customers

“The most valuable product is one our partners and customers need. Creating, from the ground up, a high-power module that meets customers’ requirements is the inspiration behind Hi-MO 5.” Dennis She, Senior Vice President, LONGi Solar, said. “To do that, we engaged the full force of LONGi’s innovations and insights from our customers. The value of innovation lies in applications. The mass production of advanced technology can deliver true value. We look forward to delivering value, higher power and lower LCOE to our global partners and customers that enable a new wave of photovoltaic grid parity.”

Product design based on industry insights and real-world applications

The starting point in the development of Hi-MO 5 was insights from the PV industry and analysis of customer values. LONGi further considered real-world applications and the practicality of its new Hi-MO 5 module in the logistics chain.

The working current of LONGi Hi-MO 5 module is about 13A. Including bifacial gain, the operating current remains within the maximum input current range of the inverter, with no power generation losses. The module length is compatible with 1P and 2P horizontal single axis tracking systems.

Hi-MO 5 adopts bifacial a "double glass with frame" design that provides exceptional strength for high load capacity. The strength of the frame negates the need for a cross-beam, hence there is no shading losses at the back of the module.

In BOS simulations using fixed brackets and centralized inverters, LONGi Hi-MO 5 module can reduce BOS costs by more than ¥8 cents/W (US$1.2 cents/W) when compared to mainstream products in the market. With string inverters, Hi-MO 5 can improve the capacity ratio of the power plant, reduce AC equipment cost, and bring about the lowest LCOE for large power plants. LONGi has partnered with more than 20 global customers to verify the BOS savings, lowest LCOE and high performance of Hi-MO 5 modules in real world applications.

Driving the PV industry forward with breakthrough innovation in volume production

LONGi firmly believes that continuous innovations that can be brought quickly into volume production delivers true value for its partners and customers.

The module production capacity of LONGi has increased 20-fold: from 1.5GW in 2015 to 30GW in 2019. Hi-MO 5 will be produced in volume and receive IEC/UL certification in September, 2020. The production capacity of Hi-MO 5 will reach 12GW in Q3 2020, guaranteeing a stable supply for global customers.

LONGi Product Portfolio


The Hi-MO 5 range includes 66C and 72C formats, in bifacial and monofacial applications. The 72C version deploys the traditional 6 rows design in a 72-cell layout with front-side power up to 540W, which is the optimal choice for the ultra-large power plants worldwide. The 66C module has front power of 495W and a smaller footprint that broaden its applications.

Concurrently, LONGi’s Hi-MO 4 module, launched in 2019, will continue in its product portfolio and is the most competitive product suited for residential, C&I and utility-scale power plants. Hi-MO 4 module and Hi-MO 5 module will co-exist in LONGi’s product lineup.