Why Does a Drone Use Dual or Multi-Battery System?

As the applications of drones continue to expand, the demand for high payload capacity and longer flight times has increased. More and more drones are now using dual or multi-battery systems, which offer numerous benefits but also come with some challenges. What are the pros and cons of these multi-battery systems? Is this becoming a trend? Would you prefer to use multiple batteries or a single battery? This article will address some common questions about the use of multi-battery systems in drones.

What Is a Dual or Multi-Battery System Used in a Drone?

A dual or multi-battery system in a drone uses two or more batteries simultaneously to increase overall energy capacity, extending flight time and enhancing reliability. By connecting batteries in parallel, drones can benefit from improved load distribution and redundancy, ensuring continued operation even if one battery fails. This setup is common in applications like delivery, surveying, and emergency response, offering advantages such as longer flight durations and the ability to carry heavier payloads. However, it also introduces challenges like increased weight, complexity, and cost.

Why Does a Drone Use Dual or Multi-Battery System?

  ●Extended Flight Time: Multiple batteries can significantly increase the overall flight time of a drone by providing more energy capacity. This is crucial for long-distance deliveries.

  ●Redundancy and Reliability: Using multiple batteries adds a layer of redundancy. If one battery fails or its capacity decreases unexpectedly, the drone can continue operating using the remaining battery(s), enhancing safety.

  ●Load Balancing: Distributing the power load across multiple batteries can prevent overheating and prolong the life of each battery. This can also help maintain optimal performance during flight.

  ●Higher Power Demand: Some logistics applications require more power, especially when carrying heavy payloads or navigating challenging terrains. Using multiple batteries can provide the necessary power.

  ●Rapid Swapping: Drones equipped with multiple batteries can be designed for quick battery swaps, reducing downtime between missions and enhancing operational efficiency.

What Are the Technical Difficulties of the Dual or Multi-Battery System?

While dual or multi-battery systems offer significant advantages in terms of flight time and redundancy, they also present several technical challenges:

  ●Synchronization: Ensuring that both batteries are synchronized in terms of charge levels and health status can be challenging. If one battery discharges faster than the other, it could lead to imbalances that affect flight time and safety.

  ●Load Sharing: Balancing the load between the two batteries to optimize performance while preventing overheating or over-discharging can be complex.

  ●Fault Tolerance: If one battery fails or provides incorrect data, the system needs a robust way to handle this without compromising flight safety.

  ●Interference: The wireless communication between batteries and the drone's systems can be susceptible to interference, requiring strong error-checking and redundancy protocols.

  ●Battery Management System (BMS) Integration: Integrating both batteries into a cohesive BMS that can manage individual battery health while providing overall system metrics adds complexity.

  ●Weight and Space Constraints: The need to accommodate two batteries adds weight and requires efficient design to fit within the drone's structure while ensuring proper ventilation and cooling.

What Is the Biggest Challenge and How to Solve It?

The biggest technical difficulty when using multiple batteries in drones is managing battery imbalance and health monitoring. This challenge can lead to issues such as reduced performance, shortened flight times, and potential safety hazards if not addressed properly. When batteries are connected in parallel, differences in individual battery capacities, charge states, or health can lead to imbalances. This can cause one battery to discharge faster than others, resulting in over-discharge, overheating, or premature failure. In actual use, it's often the case that different batteries have different voltages, and current from the high-voltage battery will flow towards the low-voltage battery, which can be very dangerous.

To ensure that the voltages of multiple batteries are the same during use and prevent current from flowing from a higher-voltage battery to a lower-voltage battery, several strategies and technologies can be employed:

1. Battery Management System (BMS)

Voltage Monitoring: An advanced BMS continuously monitors the voltage of each battery cell. It can detect when batteries are out of balance and initiate corrective actions, such as adjusting charging rates.

Active Balancing: Some BMS designs include active balancing, which redistributes charge from higher-voltage batteries to lower-voltage ones, keeping them balanced during use.

2. Cell Balancing Circuits

Passive Balancing: This method uses resistors to bleed off excess voltage from the higher-voltage cells until all cells reach the same voltage. While effective, it may generate heat and take time.

Active Balancing: This involves using inductors or capacitors to transfer energy from higher-voltage cells to lower-voltage ones, allowing for more efficient balancing without heat generation.

3. Isolation Techniques

Diodes: Schottky diodes or FETs can be used to prevent reverse current flow. If one battery’s voltage is lower than the others, the diode will block current from flowing back into it, protecting against over-discharge.

Relay Systems: Using relays can isolate batteries when voltage discrepancies are detected, ensuring that only batteries with similar voltage levels are connected during operation.

4. Voltage Regulation

Buck or Boost Converters: Integrating DC-DC converters can help regulate the voltage output from each battery, ensuring that they are within the same range before being supplied to the load. This can prevent voltage imbalances during operation.

5. Equalization Charging

Equalization Procedures: Before use, batteries can undergo an equalization charging process where they are charged to the same voltage level. This can help ensure that all batteries start at similar states of charge.

6. Regular Monitoring and Maintenance

Periodic Checks: Regularly checking the voltage and health of each battery can help catch imbalances before they become problematic. This may include manual checks or automated systems that provide alerts.

7. User Alerts and Feedback Systems

Real-Time Feedback: Providing operators with real-time data on battery voltages can help them make informed decisions and take corrective action if imbalances occur.

Is the Use of Dual or Multi-Battery System a Trend?

As drone technology advances and applications expand, the use of multiple batteries will likely continue to grow across these and other sectors, enhancing the versatility and efficiency of drone operations. This trend is becoming increasingly common in across various application. Here are some relevant application areas and specific cases:

1. Logistics

  ●Delivery Drones: Companies like Wing (a subsidiary of Alphabet) and Amazon Prime Air are exploring dual-battery systems to increase range and reliability for package delivery.

  ●Cargo Drones: Zipline and Volansi use drones equipped with multiple batteries to deliver medical supplies in remote areas, ensuring they can cover long distances without interruptions.

2. Agriculture

  ●Crop Monitoring: Drones like the DJI Agras series use multiple batteries to cover large fields, enabling longer flight times for tasks such as crop monitoring and spraying.

  ●Precision Agriculture: Companies like Sentera employ dual-battery systems in their drones to ensure extended operational periods during data collection and analysis.

3. Surveying and Mapping

  ●Aerial Surveying: Drones like the senseFly eBee X use multiple batteries to facilitate long-duration flights for detailed mapping and surveying, covering expansive areas without interruptions.

  ●3D Mapping: Companies such as Pix4D utilize drones with dual batteries to maximize data acquisition efficiency in 3D mapping projects.

4. Environmental Monitoring

  ●Wildlife Tracking: Drones equipped with multiple batteries can conduct longer flights to monitor wildlife and gather data over larger habitats, enhancing conservation efforts.

  ●Pollution Monitoring: Drones like the Parrot Anafi USA are used for environmental assessments, benefiting from extended flight times provided by multiple batteries.

5. Public Safety and Emergency Response

  ●Search and Rescue Operations: Drones used by organizations like Drones for Good and emergency services often have dual-battery systems to ensure they can operate longer during critical missions.

  ●Disaster Relief: Drones deployed in disaster-stricken areas utilize multiple batteries to maintain operational capabilities for assessing damage and delivering supplies.

6. Construction and Infrastructure Inspection

  ●Site Surveys: Drones such as the DJI Matrice 300 RTK use dual batteries to facilitate long-duration site surveys and inspections, reducing downtime.

  ●Infrastructure Inspection: Companies like Skycatch utilize drones with multiple batteries to conduct thorough inspections of bridges, towers, and other structures without frequent recharges.

7. Film and Photography

  ●Cinematography: High-end drones like the Freefly Alta 8 are designed to carry multiple batteries, allowing filmmakers to shoot for extended periods without interruptions.

  ●Aerial Photography: Drones used for professional photography and videography benefit from dual-battery setups to ensure longer flight times and capture more content.

Advantages and Disadvantages of Dual or Multi-Battery Systems

Advantages of Dual or Multi-Battery Systems

  ●Extended Flight Time: Multiple batteries provide greater overall energy capacity, allowing for longer flight durations, which is essential for applications like delivery and surveying.

  ●Redundancy and Reliability: If one battery fails or experiences a drop in performance, the remaining batteries can continue to power the drone, enhancing operational safety.

  ●Load Distribution: Distributing the load across several batteries can prevent overheating and prolong the lifespan of each battery by reducing stress on individual units.

  ●Flexible Payload Capacity: With increased battery capacity, drones can carry heavier payloads or additional equipment without compromising flight time.

  ●Rapid Swapping: Some designs allow for quick battery swaps, minimizing downtime and maximizing operational efficiency.

Disadvantages of Dual or Multi-Battery Systems

  ●Weight: Adding multiple batteries increases the overall weight of the drone, which can negatively impact performance and agility.

  ●Complexity: The integration of multiple batteries adds complexity to the drone’s design, including the need for advanced battery management systems and balancing circuits.

  ●Maintenance: More batteries require more maintenance and monitoring, increasing the operational burden on users.

In addition to using multiple batteries, there are now some other ways to extend flight time:

  ●High-Efficiency Propulsion Systems: Using more efficient motors and propellers can reduce power consumption, allowing for longer flight times with existing battery configurations.

  ●Energy-Dense Batteries: Advancements in battery technology, such as lithium-sulfur or solid-state batteries, offer higher energy densities, which can lead to longer flight times without needing multiple units.

  ●Hybrid Systems: Combining batteries with fuel-based generators or other energy sources can extend flight times significantly, providing a steady power supply for longer missions.

  ●Efficient Flight Planning: Optimizing flight paths to minimize energy expenditure, such as using altitude changes or avoiding adverse weather conditions, can enhance overall flight duration.

  ●Lightweight Materials: Using lightweight materials for the drone's frame and components can reduce overall weight, allowing for longer flight times.

  ●Energy-Efficient Components: Using energy-efficient components, such as low-power sensors and processors, can help conserve battery power.

In conclusion, the adoption of dual or multi-battery systems in drones is becoming increasingly prevalent as the demand for extended flight times and reliable performance grows across various applications. As drone technology continues to evolve, innovations in battery management and alternative energy sources will further enhance operational efficiency and safety. As a global leading lipo battery manufacturer, Grepow offers smart UAV batteries equipped with advanced Battery Management Systems (BMS) that are specifically designed to seamlessly integrate with dual or multi-battery applications. This technology is crucial for ensuring optimal performance and safety in drones that require high energy capacity and reliability for demanding tasks. If you have any questions or needs, please feel free to contact us at info@grepow.com.