Battery Capacity Calculator & kWh to Ah Conversion Tool
Size your 48V / 51.2V LiFePO4 battery system in seconds. Convert kWh to Ah, estimate runtime and backup time, and right-size your energy storage for home, commercial and industrial loads.
Battery Capacity Calculator
Enter your battery voltage, capacity and load. Total energy, usable energy, runtime and required capacity update live as you type.
1 · Battery & Load Inputs
2 · Results
DoD limits how much of the battery you should use each cycle; 80% is the recommended value for LiFePO4. Actual usable capacity is affected by temperature, discharge rate and battery age — always keep a safety margin in real deployments.
Note: dawnice "48V" series batteries use a 51.2V nominal voltage (16-cell LiFePO4 architecture), which is why a 100Ah pack stores 5.12kWh rather than 4.8kWh. Each preset fills the calculator with a realistic load for its use case.
kWh · Ah · Watts · Amps Converter
Four conversion tools in one. Enter any two values in a tab and the third is calculated automatically.
How to Size Your LiFePO4 Battery
Sizing a battery comes down to one simple relationship: energy equals voltage times capacity. A 48V, 200Ah LiFePO4 battery stores 48 × 200 = 9,600Wh, or 9.6kWh of total energy. That figure tells you how much electricity the battery holds — but it is not the full amount you should safely use.
LiFePO4 chemistry is typically rated to about 80% depth of discharge (DoD). Using 80% of a 9.6kWh pack gives you 7.68kWh of usable energy. We recommend staying inside this limit to protect cycle life. Actual usable capacity is also affected by temperature, discharge rate and battery age, so keep a safety margin on top.
Next, match the battery to your load. Divide usable energy by average load power to estimate runtime. A 7.68kWh usable pack running a 500W load lasts about 15.4 hours; running a 2,000W load, about 3.8 hours. If you know how long backup must last, work backwards: required capacity (Ah) = load (W) × target hours ÷ voltage ÷ DoD.
For commercial and industrial loads in the 1–10kW range, a 48V or 51.2V system is the practical choice. Higher voltage means lower current for the same power, so cabling is thinner, cheaper and safer — and you can parallel multiple batteries to scale capacity as the business grows.
If you operate in markets with unstable grids — such as parts of Africa, including Nigeria — plan for 8 to 12 hours of backup capacity per day. Size for the longest expected outage, not the average, and remember that peak loads usually exceed your average draw. Start with your daily load, add your outage target, and let the calculator above show you the numbers.
Why Choose 48V / 51.2V Systems
Higher efficiency
Lower current means fewer resistive losses in cabling and connections, so more stored energy reaches your inverter and appliances.
Thinner, cheaper cabling
A 48V system carries the same power at roughly a quarter of the current of a 12V system, cutting cable gauge, connectors and installation cost.
Easy parallel expansion
Multiple 48V/51.2V packs connect in parallel to scale from a few kWh to tens or hundreds of kWh without redesigning the system.
Mainstream inverter compatibility
48V is the industry-standard input for leading hybrid inverters, solar controllers and chargers, simplifying procurement and spare parts.
Stable commercial performance
Built for daily B2B cycling with BMS protection, consistent voltage output and predictable service life for business-critical loads.
Battery Calculator FAQ
How do I calculate the total energy of a LiFePO4 battery?
What depth of discharge (DoD) should I use for LiFePO4 batteries?
Why is my 48V 100Ah battery rated 5.12kWh instead of 4.8kWh?
How long will my battery run my appliances?
How do I convert kWh to Ah?
How much backup capacity should I plan for in Nigeria or other grid-unstable markets?
Ready to Power Your Business?
Dawnice Designs and Manufactures LiFePO4 Batteries, Commercial & Industrial BESS and Containerized Energy Storage for African and Nigerian Projects — with Factory-Direct Pricing and Engineering Support.
Free battery sizing and quotation for commercial & industrial projects · response within 24 hours.

