DAHON Unio E20 & K-One 36V Seatpost Battery Rebuild | 10.5Ah Upgrade
DAHON 36V Seatpost Battery Rebuild – Unio E20 & K-One
Bring your original DAHON seatpost battery back to life without paying the cost of replacing the complete battery assembly.
E-Bike Marketplace now offers an in-house rebuild service for the 57mm DAHON seatpost battery used with compatible Unio E20 and K-One electric bicycles.
The original DAHON 57mm replacement battery is rated at 36V 9.5Ah. Our upgraded rebuild is designed to increase capacity to approximately 36V 10.5Ah using a completely new matched set of premium 18650 lithium-ion cells while retaining your original DAHON battery enclosure and compatible electronics whenever serviceable.
36V 10.5Ah Capacity Upgrade
Instead of simply restoring an aging battery, our goal is to improve it.
Original DAHON specification:
- 36V nominal
- 9.5Ah
- 57mm seatpost battery
EMP upgraded rebuild:
- 36V nominal
- Up to 10.5Ah
- Approximately 378Wh
- New matched 18650 lithium-ion cells
- Original seatpost enclosure retained
- Original connector system retained
- Battery protection system tested
- Full charge/discharge and safety testing before return
The 10.5Ah rebuild provides approximately 10% more rated capacity than the original 9.5Ah battery, giving riders additional usable energy while preserving the clean, integrated seatpost design of the DAHON bicycle.
Rebuild Price – $549
Our price: $549 + return shipping
This is a battery rebuilding service. You send us your existing DAHON seatpost battery and we rebuild the internal battery pack.
A complete replacement 57mm DAHON battery is currently advertised by DAHON at $599 sale / $699 regular price. Our service gives owners another option: retain the original battery hardware while replacing the aging lithium-ion cells and upgrading the pack's capacity where compatible.
Why Rebuild Your DAHON Battery?
Lithium-ion batteries naturally lose capacity as they age. A battery may still charge and operate while providing significantly less range than when it was new.
A professional rebuild allows us to replace the aging cell group rather than unnecessarily replacing the entire seatpost assembly.
Our technicians disassemble the battery, inspect the electronics and enclosure, replace the lithium-ion cell pack, rebuild the electrical connections, and test the completed battery before it leaves our facility.
What We Reuse
Whenever they remain serviceable, we preserve:
- Original DAHON seatpost enclosure
- Original mounting system
- Original wiring and connectors
- Original battery management/protection electronics
- Original mechanical components
The internal lithium-ion cells are replaced with a new matched cell group.
Compatibility
Designed specifically for the 57mm DAHON seatpost battery associated with compatible:
- DAHON Unio E20
- DAHON K-One
- Other DAHON models using the same 36V 57mm seatpost battery, subject to inspection
IMPORTANT: DAHON also produced K-One configurations using a 53mm seatpost battery. Please measure or verify your battery before ordering. If you are unsure, contact us with photos of your battery and label.
How the Rebuild Process Works
1. Place your rebuild order
Purchase the rebuild service online.
2. Send us your original battery
Carefully package your DAHON seatpost battery and include your contact/order information.
3. Battery inspection
Our technicians inspect the battery enclosure, electronics, connections and existing cell configuration.
4. Internal rebuild
The original aging cells are removed and replaced with a new matched lithium-ion cell group.
5. Testing and quality control
The completed battery is charged, discharged and tested for proper operation and protection functionality.
6. We ship your rebuilt battery back
Once testing is complete, your original DAHON seatpost battery is returned with its new internal cell pack installed.
Important Rebuild Disclosure
This listing is for a rebuild service and not a new DAHON battery. The customer must provide an original compatible battery.
Final rebuild specifications depend on the internal construction and condition of the battery received. Damaged enclosures, proprietary electronics, failed BMS components or previously modified batteries may require additional work. We will contact you before performing additional chargeable work.
E-Bike Marketplace is an independent battery rebuilding company and is not affiliated with or endorsed by DAHON. DAHON trademarks and model names are used only to identify battery compatibility.
🔧 Battery Rebuild Service
We rebuild your existing battery using fresh, high-quality cells to restore or increase capacity and performance.
- Full disassembly, rebuild, and testing
- Upgraded capacity options available
- Uses brand new name-brand cells
- Turnaround time: Approximately 14 business days
- Timeline includes the time it takes for us to receive your battery and complete the rebuild
⚡ Custom Battery Builds
Fully custom battery solutions designed to meet your exact specifications. This is ideal for unique applications or when a standard battery will not fit your needs.
- Custom shapes and sizes
- Custom BMS (Battery Management System) configurations
- Choice of cells and performance levels
- Option for enclosed case or raw (naked) pack
- Built specifically for your application
- Turnaround time: Approximately 21 business days
🔋 Battery Packs (Encased)
Battery packs built using one of our in-stock cases. These are a great option if you want a reliable, ready-to-fit solution.
- Uses pre-designed cases from our inventory
- Proven, reliable configurations
- Faster than fully custom builds
- Turnaround time: Approximately 14 business days
🔬 Battery Cells (Individual Cells)
We supply high-quality lithium-ion cells for repairs, upgrades, and custom builds.
- In-stock cells: Ship within 3–6 business days
- Out-of-stock (air shipping): Approximately 10 business days
- Out-of-stock (sea shipping): Approximately 40 days
📦 Shipping & Intake Process
- Place your order or request a quote
- Fill out our Battery Intake Form
- Send in your battery (include charger and key if required)
- We inspect and test your battery
- We contact you with results and recommended options
Important Information
Turnaround times begin once your battery is received and checked into our system.
During high demand periods or for complex builds, timelines may be slightly extended.
Shipping Method
- All batteries are shipped via ground service only (FedEx or UPS) in compliance with DOT and IATA regulations for lithium batteries.
- Expedited air shipping is not available for lithium battery products.
Delivery Time
- Ground shipping typically takes 3–7 business days within the U.S.
- Tracking information will be provided as soon as your order ships.
Local Pickup
- Pickup is available at our Las Vegas facility:
4856 Judson Ave Suite 155 Las Vegas, NV 89115
Monday– Thursday, 9:00 AM – 4:00 PM ( Friday by appointment).
Returns
- Returns are accepted within 14 days of delivery on unused, unopened batteries.
- For rebuilds and custom packs, all sales are final unless defective.
Important Notes
- Shipping is limited to the continental United States.
- Customers are responsible for providing a valid shipping address — carriers cannot deliver to P.O. Boxes.
- Signature may be required at delivery for higher-value battery orders.
