MadJax Ascent (All Years) (48V) Fleet Lithium Conversion Kit
MadJax Ascent (All Years) (48V) Fleet Lithium Conversion Kit - is backordered and will ship as soon as it is back in stock.
Premium Built in Safety Features
Premium Built in Safety Features
Upgrade Your MadJax Ascent to Fleet Lithium
Replace the factory lead-acid batteries in your MadJax Ascent with a single, high-performance 51V LiFePO4 pack from Fleet Lithium. Complete conversion kit included.
Choose Your Capacity
| Capacity | Range | Best For |
|---|---|---|
| 51V 65Ah | Up to 27 mi | Stock carts only |
| 51V 105Ah | Up to 50 mi | Daily driving |
| 51V 168Ah | Up to 75 mi | All-day use |
| 51V 210Ah | Up to 90 mi | Max range |
65Ah is for stock motors/controllers only.
What's Included
- 51V NexGen Fleet Lithium LiFePO4 Battery (selected capacity)
- CH5618 — 58.4V 18A LiFePO4 Smart Charger
- BR5216 — MadJax Ascent Bracket Kit
- AC0219 — AC Power Connector
- CB0917 — Cable Set (35.4")
- Digital State-of-Charge Gauge
- All mounting hardware
Key Specs
- 300A NexGen BMS with 800A peak surge
- Patent-pending fire suppression system
- Built-in cold-weather heater — activates automatically below 32°F
- Bluetooth monitoring
- 10-year warranty — designed and assembled in the USA
Fitment Guide
| OEM | Model | Years | Factory Voltage |
|---|---|---|---|
| MadJax | Ascent | All Years | 48V |
Controller Compatibility
MadJax Ascent models use a 48V controller. The Fleet Lithium 51V pack is compatible. Verify your controller model before ordering.
Will this fit my MadJax Ascent?
Yes. The BR5216 bracket kit provides a factory-fit installation.
Does my controller need reprogramming?
In most cases, no.
Does it work in cold weather?
Yes. Built-in heater activates automatically below 32°F.
*Range estimates are maximums under ideal conditions.


