Extend your range without compromise — the Shimano STEPS BT-EN405 is a 504Wh rear carrier battery engineered for the EP8 (DU-EP801) and EP6 (DU-EP600) drive systems. It delivers substantial capacity in a tidy rack-mounted form that keeps your frame profile clean and shifts the weight to the rear for balanced handling on long-distance e-bike rides.

Highlights

  • 504Wh capacity (36V / 14Ah): serious range for extended rides and commutes.
  • Rear carrier mount: mounts cleanly to the Shimano BM-EN400 second-generation rear carrier battery mount, keeping the frame uncluttered.
  • EP8 & EP6 compatible: designed for DU-EP801 (EP8) and DU-EP600 (EP6) drive units.
  • 1,000-cycle durability: retains more than 60% of initial capacity after 1,000 full charge cycles.
  • Fast charging: full charge in approximately 4.5 hours with the EC-E8004 charger; approximately 7.5 hours with the EC-E6002 charger.
  • Integrated BMS: built-in battery management system monitors and protects Li-Ion cells for consistent, long-lasting performance.
  • Real-time status: battery level displayed on compatible Shimano STEPS displays and cycling computers.

Built for Long-Distance Riding

With 504Wh on tap, the BT-EN405 is designed for riders who need serious range from a rack-mounted battery. The integrated battery management system (BMS) monitors cell health and protects against overcharge and over-discharge, ensuring longevity and consistent power delivery across the full charge curve. Shimano backs the cells with a rated cycle life of more than 1,000 full charges before capacity drops below 60% of original — that translates to years of daily commuting or weekend touring.

Seamless STEPS Integration

The BT-EN405 is part of Shimano's second-generation STEPS ecosystem and communicates directly with the EP8 and EP6 drive units. Battery status is visible on compatible Shimano STEPS displays and cycling computers, so you always know how much range remains. Charging is straightforward with the EC-E6002 or EC-E8004 charger — the EC-E8004 brings the battery to full in approximately 4.5 hours, while the EC-E6002 takes approximately 7.5 hours.

Compatibility & Fit

The BT-EN405 mounts to the Shimano BM-EN400 second-generation rear carrier battery mount (sold separately). Compatible Shimano STEPS drive units:

  • DU-EP801 (STEPS EP8)
  • DU-EP600 (STEPS EP6)

Charger compatibility: EC-E6002, EC-E8004. Operating temperature: -10°C to 50°C. Charging temperature: 0°C to 40°C. Please verify your bike's battery mount and drive unit before purchasing.

Shimano offers a limited warranty covering defects in materials and workmanship. For warranty support, return the item to Tune Cycles.
  • 504Wh (36V / 14Ah) Li-Ion capacity for extended e-bike range
  • Rear carrier mount design keeps frame profile clean — mounts to BM-EN400
  • Compatible with Shimano STEPS DU-EP801 (EP8) and DU-EP600 (EP6) drive units
  • Retains more than 60% initial capacity after 1,000 full charge cycles
  • Full charge in approximately 4.5 hours with EC-E8004 charger
  • Integrated battery management system (BMS) for cell protection and longevity
  • Battery status displayed on compatible Shimano STEPS displays and cycling computers
  • Approx. 2.65 kg — practical and well-balanced on the rear rack
Part NumberBT-EN405
ColourBlack
Capacity504Wh
Voltage36V
Capacity (Ah)14Ah
Battery TypeLithium-Ion (Li-Ion)
WeightApprox. 2.65 kg
Mount TypeRear carrier (BM-EN400)
Charge Time (EC-E8004)Approx. 4.5 hours
Charge Time (EC-E6002)Approx. 7.5 hours
Operating Temperature-10°C to 50°C
Charging Temperature0°C to 40°C
Cycle Life>60% capacity after 1,000 full charge cycles
Compatible Drive UnitsDU-EP801 (EP8), DU-EP600 (EP6)
Compatible ChargersEC-E6002, EC-E8004
Compatible Battery MountBM-EN400 (sold separately)
SKU SHM-IBTEN405LA
Barcode # 4550170234492
Brand Shimano

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