Samsung 25S Weight v power trade off in pack design - how to pick the right balance.
Discover the Samsung 25S cell for UAV applications, optimising weight and power for enhanced drone performance and endurance.
Value Propositions
Cylindrical 18650 form factor for versatile applications.
Nominal capacity of 9.125 Wh and 2.45 Ah for reliable energy supply.
Top-quartile volumetric power density of 7266 W/l for high performance.
Gravimetric energy density of 194 Wh/kg, supporting lightweight designs.
Maximum continuous discharge of 35 A, ideal for demanding UAV applications.
About the Cell
The Samsung 25S cell features a cylindrical 18650 form factor, providing a nominal capacity of 9.125 Wh and 2.45 Ah. With a volumetric energy density of 526 Wh/l, it ranks around the median compared to other cells in the database. Its gravimetric energy density of 194 Wh/kg is slightly below the median, but it excels in power density, boasting 7266 W/l, which is in the top-quartile compared to the database median of 2029 W/l. The maximum continuous discharge rate of 35 A positions it well for high-demand applications, making it a strong candidate for UAV battery pack design. The cell's lightweight design, with a mass of just 47 g, further enhances its suitability for drone applications where weight is critical.
Application Challenges
In the context of EVTOL and the weight versus power trade-off in pack design, selecting the right battery cell is crucial. Drones require a careful balance between energy capacity and weight to maximise flight time and efficiency. The Samsung 25S cell's nominal capacity of 9.125 Wh allows for extended flight durations, while its lightweight design helps in maintaining optimal power-to-weight ratios. The challenge lies in ensuring that the battery can deliver the necessary power without overheating or compromising safety, especially in demanding environments. Simulation and modelling can help predict performance under various conditions, ensuring that the chosen cell meets the specific needs of the UAV application.
Why this Cell
The Samsung 25S cell is an excellent choice for UAV applications due to its impressive specifications. With a volumetric power density of 7266 W/l, it is in the top-quartile compared to the database median, ensuring that it can deliver high power outputs efficiently. The maximum continuous discharge of 35 A allows for robust performance during demanding flight scenarios, making it suitable for applications requiring high energy density. Additionally, its gravimetric energy density of 194 Wh/kg, while slightly below the median, still supports lightweight drone designs, crucial for enhancing flight time and overall mission endurance. This balance of power and weight is essential for effective UAV battery optimisation.
How Model-Based Design Helps
Simulation and model-based design play a vital role in optimising UAV battery pack design. By modelling the thermal behaviour and voltage response of the Samsung 25S cell under various load profiles, engineers can predict how the cell will perform in real-world conditions. This includes assessing heat generation and usable energy across different discharge rates. For instance, simulating the maximum continuous discharge of 35 A helps identify potential overheating issues and ensures that the battery can maintain performance without compromising safety. Furthermore, these simulations enable engineers to make informed decisions about cell selection, ensuring that the chosen battery meets the specific requirements of the mission profile, ultimately leading to improved UAV performance and reliability.
