Let’s talk about the powerhouse of a quadcopter. Yes, we are here to discuss about the very cardinal component of a quadcopter, the batteries. They play a pivotal role in helping a drone achieve a perfect equilibrium between flight time and their performance. Batteries with lithium is mostly preferred because of their high energy densities and very high discharge capabilities.
While looking for a drone battery, you will come across two primary chemistry namely, Lithium polymer (LiPO) and Lithium polymer high voltage (LiHV). The major difference between the two mentioned here is that the former has a fully charged voltage of around 4.2V as compared to the latter cell which has a voltage of 4.35V at full charge. A LiPO battery is considered to have a resting or nominal voltage of 3.7V versus a LiHV which usually has a storage voltage of 3.8V. Whereas a comparison drawn with respect to the performance of these batteries, a LiHV battery will provide more power initially but abruptly drops in voltage when it gets discharged whereas a LiPO battery discharges in a linear fashion making it easier to qualitatively estimate the flight time that remains.
The difference in the potential energy between the positive and the negative terminals of a battery is called the battery voltage. LiPO packs are most commonly sold in configurations that are calibrated as 1S, 2S, 3S, 4S, 5S, 6S and likewise where a digit is followed by the letter ‘S’ that stands for number of cells in that particular pack. More number of cells that are grouped together just ensures that the overall battery pack will be capable enough to provide more voltage. A higher FPV Drone Battery voltage ensures that the pack is able to provide more power to your quadcopter without increasing the current or amp that is drawn.
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Battery capacity is generally calculated in milliamp hours (mAh) which is a unit that describes the current a battery can supply for a given unit of time. As for an example, a 1500mAh battery is capable of supplying about 1500 milliamps (1.5A) of current for an hour, 3000mA (3A) of current for a period of 30 minutes, 6000 mA (6A) for a total time of 15 minutes and so on and so forth. Now, we will take up the concept of FPV drone battery capacity or most commonly addressed as the famous C-rating. So the amount of current that a battery is able to supply continuously for a given charge cycle is determined by C-rating of that battery. The maximum safe current drawn is usually calculated with the help of a simple formula that is the multiplicative product of battery capacity in mAh and the C-Rating. Larger capacity batteries can usually provide more current as their internal electrodes have a greater surface area.
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When it comes to any appliance, safety should always be of paramount importance because it is better to be safe than sorry, agree?? One must not undermine the safety of these LiPo batteries. Since they are such a store house of energy condensed in such a small profile, they are occasionally prone to lit up. Such a situation is less likely to occur but if it does, it may result into a lot of damage. It is most probable to happen while the battery is faulty or is charging or discharging. To avoid such a mishap, one must make use of fire-proof bags and boxes to keep the battery.
In order to properly dispose a LiPO battery, the safest alternative is to first discharge the pack using a battery charger and then to connect the power leads to a 12V incandescent light bulb for several hours. This will ensure that the LiPO battery is fully discharged to 0V. However tempting it may appear, it is not advisable to dispose of a LiPO battery by puncturing or damaging it. Once you have discharged LiPO completely, it is recommended to cover the battery terminals and recycle it. Such a recycling process ensures that any negative environmental impact is minimized.
Hoping that our little attempt to provide you with the basic understanding of multirotor batteries must have had a significant impact on your learning journey. Keep hustling!!