Surron Ultra Bee 72V Upgraded Battery
Drop-in replacement battery
Designed to match the stock Ultra Bee battery size, this pack fits the bike with no battery-lid modification required. It delivers double the power output while remaining fully compatible with the stock controller. A new bike power harness is included, built with a reliable high-current fuse for added protection, and the pack comes with all parts needed for the communication cable, providing full compatibility with stock and aftermarket controllers.
Upgraded cell performance
Unlike the pouch cells in the stock battery, which heat up under load, this battery uses high-performance Molicel cells for greater efficiency and durability, delivering their full rated current while maintaining a long cycle life, unlike weaker power cells such as the 50S. Expect increased range, more consistent power at lower charge levels, and reduced heat under normal riding conditions.
Relocated charge port
The battery features a standard XT60 charge port on the pack, and also includes a custom XT60 port mounted in place of the USB port for a cleaner, more accessible charging solution.
Note: The dashboard will no longer display battery percentage. The remaining power can be monitored via the Bluetooth BMS app or the built-in screen on the top lid.
Click here for the install guide
Current Shipping Time: 6-7 weeks
Includes:
- Battery
- 15A Charger
- QS10 Bike Power Harness
63Ah Specs:
| Cell: | Molicel P42A 4200mAh |
| Configuration: | 20s15p |
| Max Voltage: | 84.0V |
| Capacity: | 4,536Wh / 63Ah |
| Power Connector: | QS10 |
| Max Power: | 630A | 45kW |
| Max Charge Current: | 20A |
67.5Ah Specs:
| Cell: | Molicel P45B 4500mAh |
| Configuration: | 20s15p |
| Max Voltage: | 84.0V |
| Capacity: | 4,860Wh / 67.5Ah |
| Power Connector: | QS10 |
| Max Power: | 675A | 48kW |
| Max Charge Current: | 20A |
75Ah Specs:
| Cell: | Molicel P50B 5000mAh |
| Configuration: | 20s15p |
| Max Voltage: | 84.0V |
| Capacity: | 5,400Wh / 75Ah |
| Power Connector: | QS10 |
| Max Power: | 825A | 59kW |
| Max Charge Current: | 20A |
Other Features:
- Metal enclosure with a water-resistant, durable build.
- Battery monitor screen on the top lid showing percentage, voltage, and cell temperature.
- Smart BMS with Bluetooth monitoring.
- Discharge is BMS bypassed for full, uninterrupted power (BMS is for charge only – click to learn more).
Dimensions:
| Height: | 13.25" (336mm) |
| Width: | 7" (177mm) |
| Length: | 8.75" (222mm) |
| Weight: | 54.8lbs (24.8kg) |
BMS App:
- iOS: Xiaoxiang BMS
- Android: Overkill Solar
Built and shipped from Canada 🇨🇦
Cell Comparison
All Molicel 21700 cells offer incredible power, but they are optimized for different priorities. Use this guide to select the best balance of efficiency, performance, and cost for your build.
| Cell Model | Key Feature | Best For |
|---|---|---|
| P42A (4.2Ah) | High Power / Lower Cost | Great for performance on a budget, strong output, and cost-focused builds. |
| P45B (4.5Ah) | More Capacity / Low Resistance | The ideal middle ground: lower voltage sag, cooler operation, and improved efficiency. |
| P50B (5.0Ah) | Maximum Capacity / Best Efficiency | Premium performance: highest capacity, minimal voltage drop, and lowest operating temperatures. |