Choosing the best drone battery for your project might be challenging because there are hundreds of options available. Deciphering the battery's numerous performance indications, which include cell configuration, capacity, and discharge rating, is one of the biggest hurdles.

Selecting the appropriate battery for your drone can extend its lifespan in addition to enhancing performance. Your battery will ultimately run out, just like your engine and propeller, but you may delay this by selecting the right one and using it properly.

Selecting the right battery is crucial for maximizing the performance and longevity of drones, and at Procurabl, we understand the intricacies involved in making this choice. Here's a comprehensive guide to understanding Lithium Polymer (LiPo) batteries, which are widely used in the drone industry due to their high energy density and reliability.

Understanding LiPo Batteries

Lithium polymer (LiPo) batteries are the most often utilized battery type in drones. Lithium-based cathode and anode separated by a polymer electrolyte make up LiPo batteries. LiPo batteries are distinct from ordinary lithium-ion (Li-ion) batteries in that their electrolyte component is made of solid polymer rather than liquid. Poly(methyl methacrylate) (PMMA), poly(acrylonitrile) (PAN), poly(vinylidene fluoride) (PVdF), and poly(ethylene oxide) (PEO) are examples of common polymer electrolytes. They can be dry, porous, or in the form of a gel.

Like other Li-ion batteries, LiPo batteries operate on the same principle: chemical energy is transformed into electrical energy as electrons move from the anode to the cathode of the battery, producing an electrical current. While lithium carbon (such as graphite) is present in the anode, a lithium metal oxide (such as lithium-cobalt oxide (LiCoO2)) serves as the cathode's source of lithium ions. There is a charge gradient in the cell between the anode and cathode because the electrolyte interacts with the anode to produce electrons. Electrons go from the negatively charged anode to the cathode via a conducting wire. As a result, the entire system experiences an electrochemical redox process, or reduction/oxidation, in which the cathode acquires electrons and is reduced and the anode loses electrons and becomes oxidized.

Compared to nickel cadmium or nickel metal hydride batteries, lithium-based batteries have a higher energy density, which allows them to hold more energy while weighing less. In terms of energy density, LiPo batteries are comparable to Li-Ion batteries, however they are more widely used due to their lower leakage rate.

LiPo batteries have an energy density of between 140 and 200+ Wh/kg for weight and 250 to 350+ Wh/L for volume. When creating a drone, volume energy density is crucial to take into account so the battery fits on the frame; however, energy density by weight is more critical for performance estimates. Your budget could also be a limiting issue because increased density also means higher costs.

Basic Specifications of LiPo Battery

Capacity: Battery capacity is specifically defined as the number of hours of current or power the battery can provide. Common units are the ampere-hour (Ah) and the watt-hour (Wh). If a battery has a capacity of 1 Ah, you can draw 1 A of current for one hour. If the capacity is 1 Wh, the battery will provide 1 W of power for one hour.

Voltage: The voltage rating of the battery will allow you to determine your motor speed and amperage. Since motors are rated in Kv with the unit RPM/Volt, the number of volts your battery can supply will determine how fast your motor will rotate.

Cell Configuration: The cell configuration is sometimes present on the label and describes the number and layout of LiPo cells in the battery. A LiPo cell has a nominal voltage of 3.7 V and several LiPo cells can be connected in series. A 4S battery would have four LiPo cells in series (S), giving a 14.8 V battery (4 x 3.7 V = 14.8 V). A battery might also have a code like 4S2P, which tells us that there are four cells connected in series and two cell sets connected in parallel (P), for a total of eight LiPo cells. 

Discharge/ C Rating: The discharge rate or the C rating is a measure of how quickly the battery can safely discharge. If a battery has a C rating of 25 and a capacity of 5800 mAh/ 5.8 Ah, you could safely discharge it at 25 times the capacity of the battery, 25 x 5.8 = 145 Ah. With continuous power at that rate, the 5.8 Ah battery could be discharged in 2.4 minutes ((5.8 / 145) x 60 = 2.4). Batteries may also have a range or ‘peak’ discharge rate, where the battery may exceed its constant power output for a short period of time without overheating, such as during a sudden climb or correction. A higher C rating is great for applications like drone racing that require bursts of speed, since the battery can deliver the charge needed very quickly. 

Choosing the Right LiPo Battery

When selecting a LiPo battery, consider the following:

1. Capacity: Higher capacity batteries offer longer flight times but come with added weight. It's essential to balance capacity with the drone's total weight to ensure optimal performance.

2. Voltage and C Rating: The voltage determines the motor's RPM, with higher voltages providing more power. The C rating indicates the maximum discharge rate, which is crucial for high-performance drones requiring quick bursts of power.

3. Current Draw: Ensure the battery can handle the maximum current draw of your drone's motors to avoid overheating and potential damage.

Also read: The Evolution of Drones

Procurabl's Role in Advancing Drone Technologies

Procurabl offers comprehensive solutions for manufacturing the best components, including high-quality LiPo batteries, to meet the unique needs of drone manufacturers. See our capabilities for battery pack manufacturing. Our global network and deep industry expertise ensure that clients receive the best products, whether for high-performance racing drones or long-endurance agricultural UAVs or HALEs.

At Procurabl, we are committed to empowering enterprises and fostering a collaborative ecosystem that benefits all stakeholders. Join us in this journey towards a more resilient and prosperous future.

For more information on how Procurabl can transform your procurement strategy, visit our website or reach out to us directly.

Together, we can shape the future of Drone supply chains.