Keywords: LiFePO4 battery pack, voltage calculation, capacity calculation, energy storage, series and parallel connection
Accurate voltage and capacity calculation is crucial when assembling LiFePO4 battery packs for energy storage. Knowing how different configurations affect system performance helps you design more efficient and reliable solutions.
1. Voltage in Series Connection
Each LiFePO4 cell typically has a nominal voltage of 3.2V and a full charge voltage of 3.65V.
In series, the total voltage adds up:
Total Voltage = Number of Cells × Cell Voltage
Example:
8 cells × 3.2V = 25.6V system
At full charge: 8 × 3.65V = 29.2V system
This setup is ideal for 24V systems, such as solar inverters and electric mobility applications.
2. Capacity in Parallel Connection
When batteries are connected in parallel, the total capacity (Ah) increases, but voltage remains the same.
Total Capacity = Number of Cells × Cell Capacity
Example:
4 cells × 100Ah = 400Ah capacity at 3.2V.
This means your system can deliver higher current for longer durations, perfect for backup power and off-grid storage.
3. Combining Series and Parallel
Large-scale energy storage often requires both voltage and capacity increases. A 4S2P configuration means four cells in series and two in parallel:
- Voltage = 4 × 3.2V = 12.8V
- Capacity = 2 × 100Ah = 200Ah
This flexibility allows LiFePO4 batteries to scale easily for different applications—from home solar storage to industrial ESS.
4. Safety Considerations
- Ensure all cells have the same voltage before assembly.
- Use high-quality busbars and connectors to reduce resistance.
- Install a BMS that supports both series and parallel balancing.
Conclusion
Proper calculation of voltage and capacity guarantees your LiFePO4 system performs safely and efficiently. Whether designing for 12V, 24V, or 48V applications, understanding these relationships is the foundation of reliable energy storage engineering.