72V 9Ah Molicel P45B eBike Battery
Ultra-Compact • High-Output • Built in the USA for Serious Mid-Drive Power
 
Meet the smallest high-power battery in our Molicel lineup—perfect for riders who need maximum punch in a compact footprint. The Bicycle Motor Works 72V 9Ah Molicel P45B is engineered specifically for high-current mid-drives, delivering instant acceleration, impressive torque, and reliable high-amp output in a lightweight, portable pack.
 
Every battery is custom-built in Bethlehem, PA, professionally sealed, protected, and assembled using only genuine Molicel P45B 21700 cells, known for their legendary discharge performance.
This is the battery for riders who want big power in a small package.
 
 
⚡ Key Performance Benefits
90A Continuous / 120A Burst BMS
Designed to feed high-current motors with stable, controlled output. Perfect for CYC, BBSHD Ludicrous, ASI/BAC systems, and more.
Molicel P45B – 2P High-Discharge Configuration
Each P45B cell handles 45A continuous, giving this 20s2p pack a combined 90A continuous output potential.
Ultra-Compact 72V Power
Fits easily into frames, bags, and backpacks—ideal for stealth setups or lightweight builds.
Professionally Built, Protected & Sealed
Rigid internal frame, double-layer shrink, and thick rubber armor for durability.
 
 
🔋 Technical Specifications
Voltage: 72V
Capacity: 9Ah
Energy: 648Wh
Cell Type: Molicel P45B 21700 (4500mAh / 45A)
Configuration: 20s2p
BMS: 90A continuous • 120A max • Temperature protected
Discharge Connector: XT-90S anti-spark
Charge Connector: Heavy-duty XT-60
Dimensions: No larger than 9" × 4" × 3"
Encasement: Thick rigid casing + double shrink + rubberized outer layer
Weight: Extremely lightweight (backpack-friendly)
 
 
🚀 Why Choose 72V for Your Build?
Sharper throttle response
More efficient power delivery
Higher torque and top-end speed
Lower amp draw for the same watt output
Perfect for riders who want maximum performance from compact setups
More voltage = More fun + More efficiency.
🔧 Built for Heat Dissipation & Reliability
Just like all Bicycle Motor Works high-current batteries, this 72V pack features:
Tight internal structure for superior heat dissipation
No unnecessary air gaps (air = insulation = heat trapping)
Nickel + copper busbar construction
Precision spot-welded cell connections
Full testing on each cell and series prior to final assembly
BMS protection for charging, balancing, and temperature control
It’s built for safety, longevity, and real-world riding performance.
 
 
🛑 Safety Warning
Lithium-ion batteries are powerful energy systems and must be treated with care:
Charge ONLY with a proper lithium-ion charger.
Never leave the battery charging unattended.
Charge in a fire-safe area (BBQ grill, ammo box, or metal enclosure recommended).
Never short-circuit the battery.
Do NOT open, modify, cut wires, or change connectors.
Do not use the battery if damaged or wet—this can cause fire or thermal runaway.
Always follow safe handling practices.
If you’re unsure about compatibility or installation, contact us—we’re here to help.
 
📦 Shipping Information
All Bicycle Motor Works battery packs are built in the order received.
Shipping is typically 6–10 days, depending on build queue.
Tracking will be sent immediately upon shipment.
Reach out anytime for assistance.