In major French cities such as Paris, Lyon, and Marseille, urban electric bikes (Urban E-Bikes) have become essential tools for daily commuting and eco-friendly mobility. However, French E-bike brands, conversion kit distributors, and OEM/ODM assembly factories often encounter installation challenges when selecting downtube batteries, including limited triangle frame space, loose mounting rails, and physical dimensional mismatches under different power requirements.

To guarantee structural compatibility during downtube integration, purchasing teams must evaluate not only physical external dimensions but also core engineering parameters, including cell configuration, continuous BMS output capacity, and overload protection.

For most E-bike frames utilizing a downtube mounting design, the physical geometry of the battery casing dictates assembly feasibility and overall structural aesthetics.

• Precise Physical Compatibility: The standard casing dimensions of the Hailong downtube battery are 368 × 95 × 138 mm. This structural design specifically aligns with standard frame triangle clearances, facilitating secure rail mounting and convenient quick-release functionality.

• Weight and Center of Gravity: With an overall weight ranging between 5–8 kg (depending on cell configuration and total capacity), mounting the battery on the downtube lowers the bike's center of gravity, enhancing handling stability on urban cobblestones and uneven road surfaces.

Beyond precise geometric fit, reliable power delivery across high-frequency urban commuting and changing weather conditions in France is supported by concrete technical specs:

Built with brand-new Grade-A 18650 or 21700 cells, the pack maximizes energy density within the standardized 368 × 95 × 138 mm casing. It supports multiple voltage options (36V, 48V, 52V, 60V, and 72V) and capacities from 10Ah to 35Ah, delivering reliable range for daily city travel.

Equipped with an intelligent 20A or 30A BMS board, the system offers targeted motor matching: 20A BMS for 500W commuter motors, and 30A BMS for 750W–1000W motors. This prevents accidental over-current trips during frequent stop-and-go city traffic or slope accelerations.

Under rigorous 85% Depth of Discharge (DOD) testing, the battery maintains 800–1000 charge/discharge cycles. This longevity significantly cuts long-term maintenance and replacement expenses for fleet managers and brands in France.

For French E-bike OEMs, ODMs, and assemblers preparing for volume purchasing, the following selection process is recommended:

1. Dimensional Verification: Confirm that the frame downtube clearance accommodates the 368 × 95 × 138 mm casing dimensions prior to mass production.

2. Motor and BMS Alignment: Match the BMS specs to motor power ratings (select 20A BMS for 500W motors; specify 30A BMS for 750W–1000W motors).

3. Charger Integration: Pair with 2A–5A smart chargers to optimize charging efficiency while safeguarding cell life.

To explore full technical specifications and customization options, please visit: Hailong Battery Product . To request engineering drawings or volume quotes, please feel free to contact Us