The Shimano STEPS BT-EN606 is a 630Wh external frame battery designed specifically for second-generation Shimano STEPS e-MTB systems. Mounting on the down tube or seat tube, it keeps weight low and central for handling that stays predictable on technical terrain — without sacrificing the range serious trail riders need.

Highlights

  • 630Wh capacity (36V / 17.5Ah): substantial range for long days on the trail without needing a mid-ride charge.
  • Down tube or seat tube mounting: suits a wide range of e-MTB frame designs via the BM-EN600 battery holder.
  • Second-generation BMS: Shimano's Battery Management System optimises energy delivery and protects cell health across the battery's lifetime.
  • 1,000-cycle service life: retains more than 60% of initial capacity after 1,000 full charge cycles.
  • IPX5 water resistance: handles rain, mud, and low-pressure washing with confidence.
  • Integrated controls: built-in charge level indicator, error signal, and on/off switch for quick pre-ride checks.
  • Fast charge option: reaches 80% in approximately 3.2 hours with the EC-E8004 charger; full charge in around 4.8 hours.

Performance & Longevity

Shimano's second-generation Battery Management System continuously monitors cell conditions to deliver consistent power to the motor and extend the usable life of each cell. The proven result: the BT-EN606 retains more than 60% of its initial capacity after 1,000 full charge cycles — well above the typical industry benchmark. Whether you're charging nightly during a bikepacking trip or topping up before weekend rides, the BT-EN606 is built to last.

Design & Mounting

The BT-EN606 uses a compact external form factor that mounts to the frame via the BM-EN600 battery holder (sold separately). It fits both down tube and seat tube positions, giving frame builders and bike manufacturers flexibility in system layout. The integrated on/off switch and LED charge indicator let you check battery status at a glance without needing to power up the full system.

Compatibility & Fit

The BT-EN606 is designed for Shimano STEPS second-generation drive units. Compatible motors: DU-EP801 (EP8 series) and DU-EP600 (EP6 series). Requires the BM-EN600 battery holder for frame mounting (sold separately). Compatible chargers: EC-E8004 (recommended) and EC-E6002. Not compatible with first-generation STEPS drive units or first-generation battery mounts.

Shimano offers a limited warranty covering defects in materials and workmanship. For warranty support, return the item to Tune Cycles.
  • 630Wh / 36V / 17.5Ah capacity for extended e-MTB range
  • Mounts on down tube or seat tube — compatible with a wide range of e-MTB frames
  • Second-generation Shimano BMS for efficient power delivery and long cell life
  • Retains more than 60% capacity after 1,000 full charge cycles
  • IPX5 water resistance — rain, mud, and low-pressure wash rated
  • Integrated on/off switch and LED charge level indicator
  • Fast-charge to 80% in ~3.2 hours with EC-E8004 charger; full charge ~4.8 hours
  • Compatible with DU-EP801 (EP8) and DU-EP600 (EP6) drive units
Capacity630Wh
Voltage36V
Current17.5Ah
Water ResistanceIPX5
Charge Time (100%)~4.8 hours (EC-E8004)
Charge Time (80%)~3.2 hours (EC-E8004)
Cycle Life>60% capacity after 1,000 full charge cycles
Operating Temperature-10°C to 50°C
Charging Temperature0°C to 40°C
Mounting PositionDown tube or seat tube
Required MountBM-EN600 battery holder (sold separately)
Compatible ChargersEC-E8004, EC-E6002
Compatible Drive UnitsDU-EP801 (EP8), DU-EP600 (EP6)
ColourBlack
SKU SHM-IBTEN606A
Barcode # 4550170234706
Brand Shimano

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