Knowledge base / Brands / LONGi / Hi-MO X6

LONGi · Solar panel model

Hi-MO X6

LONGi Hi-MO X6 is a family of first-generation HPBC back-contact solar modules, created when LONGi renamed Hi-MO 6 for distributed and rooftop markets in 2023.

Specifications

SpecificationValue
Rated power (W)420-440 for LR5-54HTH; 620-630 for X6 Max LR7-72HTH, at STC
Cell typemonocrystalline HPBC back-contact; X6 Max LR7-72HTH uses TaiRay wafers
Module efficiency (%)21.5-22.5 for LR5-54HTH; 23.0-23.3 for LR7-72HTH
Dimensions (mm)1722 x 1134 x 30 for LR5-54HTH; 2382 x 1134 x 30 for LR7-72HTH
Power temperature coefficient (%/°C)-0.290 for LR5-54HTH; -0.280 for LR7-72HTH
Nominal operating cell temperature (°C)45 ± 2 for LR5-54HTH and LR7-72HTH
First-year degradation (%)under 1.5 for LR5-54HTH; under 1 for LR7-72HTH
Annual degradation (%)0.40 in years 2-25 for LR5-54HTH and LR7-72HTH
Product warranty (years)15 for the stated Explorer documents; other named variants publish different terms
Performance warranty (years)25 for the stated Explorer documents; Artist Ultra Black publishes 30 years
Performance-warranty end value (%)88.9 for LR5-54HTH; 89.4 for LR7-72HTH
Bifacialvariant-dependent: the stated Explorer modules are monofacial; Artist Ultra Black is dual-glass bifacial
MCS listingcurrent exact LR5-54HTH wattage entries at 22 July 2026

Hi-MO X6 is LONGi’s family of first-generation HPBC back-contact solar modules for distributed installations. LONGi introduced the X6 name in October 2023 as the new identity for Hi-MO 6, so the two names can appear against related LR5 model codes.

A family with several constructions

The X6 range includes Explorer, Scientist, Guardian and Artist names. It also includes original 54-cell-format modules and later X6 Max products using different wafer dimensions and larger frames. One family-wide value for power, dimensions, warranty or bifaciality would therefore be misleading.

The LR5-54HTH 420 W to 440 W document describes a single-glass monofacial Explorer module. The X6 Max LR7-72HTH document covers 620 W to 630 W in a larger single-glass format, with a different temperature coefficient, degradation profile and retained-output figure. LONGi’s European information for Artist Ultra Black describes a separate dual-glass bifacial construction with a 25-year product warranty and a 30-year power warranty.

HPBC places the cell contacts on the rear, leaving the front without conventional busbars. The X6 Max family also uses LONGi’s TaiRay wafer technology. These are family descriptions; the exact electrical values still come from the individual LR5 or LR7 datasheet.

Model code and MCS record

LR5-54HTH is the important identifier for the smaller Explorer format. The MCS Product Directory contains current entries for numerous LR5-54HTH wattages, including records under both older and newer BABT certificate series. The full wattage suffix must match because each entry is a separate certified product.

Availability

LONGi continues to publish the Hi-MO X6 family on its European site and exact LR5-54HTH MCS records are current at 22 July 2026. Availability and warranty still depend on the particular named variant and supplier documentation.

Brand

LONGi

Reference type

Solar panel model

Last reviewed

22 Jul 2026

Current status

Current in the manufacturer's UK range.