eBike & Lithium-Ion Battery Engineering Calculators
Your comprehensive guide and precision toolset for electric bicycle propulsion, custom battery pack assembly, traction resistance modeling, and long-term electrochemical lifecycle economics.
eBike Range Calculator
Decompose opposing forces—rolling tire friction, aerodynamic drag, and elevation incline—to estimate real-world distance in km and miles across custom speeds, loads, and battery sizes.
Battery Pack Builder
Design custom lithium-ion battery packs using verified 21700 cylindrical cells (EVE, BAK, Molicel, Ampace). Calculate S/P topology, thermal limits, continuous power, and complete Bill of Materials (BOM) in USD and KES.
Lifecycle & Degradation
Simulate battery capacity degradation across 800 cycles down to 70% End-of-Life. Calculate lifetime cumulative mileage, electricity charging costs, and fuel savings over petrol motorcycles.
Understanding Battery Terminology & Physics Concepts
Essential electrochemical definitions and physical principles for designing, building, and operating light electric vehicles.
Energy & Capacity Units
mAh (Milliamp Hours): Battery capacity in thousandths of an amp per hour. A 5,000mAh cell can deliver 5A for 1 hour or 1A for 5 hours.
Wh (Watt Hours): Real energy measurement. Voltage × Capacity (Ah) = Energy (Wh). A 48V 20Ah pack holds 960 Wh (0.96 kWh).
kWh (Kilowatt Hours): Large energy measurement. 1 kWh = 1,000 Wh. Equivalent to powering a 100W device for 10 hours.
Series & Parallel Configurations
Series (S): Cells connected positive-to-negative. Voltages add together while capacity remains constant. 13 cells in series = 46.8V nominal (48V tier).
Parallel (P): Cells connected positive-to-positive. Capacities add together while voltage remains constant. 3 cells in parallel of 5Ah = 15Ah.
13S3P Pack: 13 in series × 3 in parallel = 39 total cells delivering 48V 15Ah (720 Wh).
Operational & Safety Metrics
BMS (Battery Management System): Protective circuitry monitoring individual cell voltages, preventing overcharge, over-discharge, short-circuits, and thermal runaway.
C-Rating: Discharge rate relative to capacity. A 1C rate on a 5Ah cell is 5A. A 5C rate on a 4.5Ah Molicel P45B cell is 22.5A continuous.
DoD (Depth of Discharge): How deeply the battery is emptied. Limiting discharge to 80% DoD dramatically extends cycle life.
Battery Shipping & Hazmat Compliance
IATA Air Restrictions: Air transport regulations restrict lithium-ion batteries over 100 Wh on passenger aircraft and require special cargo handling.
UN3480 Sea Freight: Assembled commercial packs and raw cell crates must be packed in UN-certified packaging, labeled with Class 9 Hazmat diamond placards.