The required current strength For various applications, the amperage varies enormously, from a few amperes for small electronic devices to thousands of amperes for industrial machines. For battery systems, it is crucial to determine the correct current, as this directly affects the performance, safety, and lifespan of the system.
What is current and why is it crucial for battery systems?
Current, also known as amperage referred to as, is the amount of electrical charge that flows through a conductor per second. It is measured in amperes (A) and determines how much current a battery system can supply to connected equipment.
Current differs fundamentally from voltage (volts) and power (watts). While voltage indicates electrical pressure and power represents total energy consumption, current determines the capacity to supply power. This is essential for battery systems, as a current that is too low results in underperformance, whereas a value that is too high can lead to overheating and safety issues.
For custom batteries for industrial applications, correct amperage dimensioning is crucial for optimal performance. Electrical applications such as construction machinery, Formula E racing cars, and marine systems each have specific amperage requirements that must be calculated accurately.
How do you calculate the required current for your application?
You calculate the required current by dividing the total power of your application by the system voltage (I = P/V). For more complex systems, you must also take into account peak power, efficiency losses, and safety factors.
A practical example: an electric excavator with a power output of 50 kW at 400 V requires a minimum of 125 A (50.000 W ÷ 400 V = 125 A). For peak power during digging, this can rise to 200–250 A. In these calculations, you must also take into account:
- Inverter efficiency losses (usually 5–10%)
- Temperature influence on battery performance
- A safety margin for unexpected load peaks
- Difference between continuous and peak current requirements
For accurate calculations, you can our calculator use, which takes into account all relevant factors for your specific application.
What current do various industrial applications require?
Industrial applications vary widely in their current requirements. Construction machinery typically requires 100–500 A, rail vehicles 200–1000 A, maritime applications 50–300 A, and Formula E racing cars can reach peaks of up to 600 A.
Here are typical current ranges per sector:
Construction machines:
- Small excavators (5–10 tons): 80–150 A
- Medium-sized excavators (15–25 tonnes): 200–350 A
- Large mining machines: 400–800 A
Rail industry:
- Maintenance vehicles: 150–300 A
- Shunting locomotives: 400–600 A
- Passenger trains: 600–1200 A
Maritime applications:
- Recreational vessels: 30–100 A
- Workboats: 150–400 A
- Ferries: 500–1000 A
Racing and high performance:
- Formula E: 250–600 A (depending on power setting)
- Electric sports cars: 200–500 A
- Classic car retrofits: 100–300 A
What happens if your current is too low or too high?
Incorrect amperage sizing leads to performance issues, safety risks, and reduced battery life. A current that is too low causes voltage drop and underperformance, while excessive values can result in overheating and a fire hazard.
Consequences of insufficient current:
- Voltage drop under load
- Reduced performance of motors and actuators
- Unexpected shutdown of security systems
- Inefficient energy conversion
Consequences of excessive current:
- Overheating of battery cells and wiring
- Accelerated degradation of battery chemistry
- Increased fire risk
- Unnecessary costs for oversized components
You prevent these problems by an accurate power calculation and the use of modular energy storage systems that can be flexibly configured to the exact requirements of your application.
How do you choose the right battery configuration for your current requirements?
The correct battery configuration is achieved by using parallel connections for higher current and series connections for higher voltage. Modular configurations offer the flexibility to optimize both parameters for your specific energy consumption profile.
Parallel circuits: Increase the available current by connecting multiple battery packs in parallel. Each added parallel branch increases the available current capacity. This is ideal for applications with high current requirements, such as the electrification of heavy machinery.
Series connections: Increase the system voltage while the current remains the same. Higher voltages are more efficient for power transmission and reduce cable thickness and losses.
Hybrid configurations: Combining series and parallel connections to optimize both voltage and current. We often design configurations such as 2S3P (2 in series, 3 in parallel) or more complex arrangements, depending on the application.
Cell type selection:
- Lithium-ion for high energy density
- LiFePO4 for safety and a long service life
- Lithium titanate for extremely fast charging
Which factors influence the current requirements of your system?
Temperature, load profile, peak power requirements, and environmental conditions all have a significant influence on the current specifications of battery systems. At extreme temperatures, the available current can decrease by 20–40%.
Temperature influences: At low temperatures, internal resistance increases, causing the available current to decrease. At high temperatures (above 40 °C), systems must be downgraded to prevent overheating. Our systems are designed for extreme conditions up to 50 °C ambient temperature.
Tax profile:
- Continuous load requires different dimensioning than peak load.
- Cyclical patterns influence thermal management
- Regenerative braking energy must be captured.
Environmental Factors:
- Vibrations and shocks in mobile applications
- Moisture and corrosion in maritime environments
- Dust and contamination from construction machinery
- Altitude and air pressure in aviation applications
Determining the correct amperage for your specific application requires a thorough analysis of all these factors. Our modular energy storage solutions are specifically designed to meet the unique requirements of various industries, from Formula E racing to heavy construction equipment. For an accurate calculation of your amperage requirements and a custom-made battery solution, you can always contact Contact us.
