RC Battery & ChargerPosted by Krogh Cook on May 16th, 2021 RC LIPO BATTERY GUIDE: EXPLANATION, SAFETY, AND CAREWithout LiPo batteries, quadcopters and also drones most likely would not exist. Why? Due to the fact that no other battery supplies as much energy while supplying high quantities of present in so little of a package. This suggests: longer flight times, much better maneuverability, and also faster flying. To put it simply, more fun. However, there is a lot of complication concerning what terms mean, exactly how to correctly charge lithium polymer batteries, and how to be risk-free when using batteries. In this lipo battery overview, you'll obtain: A thorough explanation of battery specs-- Nominal and cut-off voltage, capacity, C-rating, inner resistance and more Exactly how to increase the life of your lipo battery What to seek in a lipo battery charger How to use a lipo battery charger Why equilibrium charging is very important The distinction in between different sorts of battery ports Proper lipo battery safety and care A glossary of typical lipo battery terms So, allow's start with battery specs.Battery VoltageThe first specification that many people consider when selecting a battery is the voltage. As pointed out in my post on motor Kv continuous, the rate of your electric motors is symmetrical to the voltage you supply to them so higher voltage batteries are capable of transforming motors quicker than reduced voltage batteries. The voltage of your battery will certainly identify the kind of ESC's and also motors that you will require to utilize. Lipo battery voltage is defined by the variety of cells in collection. Each cell has a small voltage 3.7 V. Different battery firms note their lipos in different ways but most individuals tend to refer to their batteries as 1S, TWO, THREE, etc The adhering to voltage graph reveals each battery designation as well as the equivalent voltage. 1S = 1 cell in collection x 3.7 V = 3.7 V. 2S = 2 cells in series x 3.7 V = 7.4 V. FOUR = 3 cells in collection x 3.7 V = 11.1 V. FOUR = 4 cells in series x 3.7 V = 14.8 V. 5S = 5 cells in collection x 3.7 V = 18.5 V. SIX = 6 cells in series x 3.7 V = 22.2 V You may additionally see lipos that make use of a letter "P" to mark voltage. For example, 2S1P or 2S2P. This is not as usual with quadcopter batteries however you may see it with LiPo's meant for other kinds of RC automobiles. " P" means the number of cells in parallel. 2S1P means "2 cells in series and 1 cell in parallel." If airplane quotes doesn't have a "P" after that it is assumed to be "1P." So 2S1P and TWO coincide thing. 3S2P indicates "3 cells in series and also 2 cells in parallel." This battery would certainly have a total of 6 cells with 2 identical teams of cells with 3 cells in series in each of those groups.Maximum Voltage as well as Cut-off Voltage.Think about the 2 battery voltage curves in Figure 1. An "ideal" battery as well as an "real" battery are shown. An ideal battery would certainly can supplying continuous voltage for the whole time it is discharging till it is entirely released. Real batteries do not behave by doing this. Rather they start at a higher voltage and afterwards their voltage will slowly reduce as the battery is released. So while an ideal battery could have a voltage of 3.7 V during the entire time it is discharging, an actual battery will certainly begin at the optimum voltage of 4.2 V As it discharges, maintain decreasing. How far will it reduce? If you allow it, it will completely release down to no volts. Nevertheless:. Battery manufacturers normally suggest you do not discharge your battery below a specific minimum voltage. This minimum voltage is called the cut-off voltage. Numerous manufacturers suggest the cut-off voltage for lipos to be 3.0 Volts. Virtually talking, this suggests you must establish your voltage alarm system to something more than 3.0 V to ensure that you can securely land your quadcopter prior to it drops listed below 3.0 V Lots of people set their alarms to 3.3 V.Battery Capacity.Battery capacity is measured in Amp-hrs or milliamp-hrs. It gives you an indication of the total energy that a battery can keep. As a whole, the higher the capability, the longer your battery will certainly last. Making use of the gas tank analogy, a high capability battery has a large gas storage tank that allows it to keep a lot of gas. The most effective means to comprehend the ability of lipos is to think about just how it is measured. The general procedure is to take a battery and find out what constant present triggers the lipo to drop listed below the battery cut-off voltage in precisely 1 hr. The capacity is then just that current times 1 hour. So a 3000 mAh ability battery will certainly drop from complete voltage to the cut-off voltage in 1 hour if you discharge the battery at 3000 mA (3 Amps). 3 Amps x 1 hr = 3 Amp-hrs = 3000 mAh. There is one vital point you require to keep in mind ... The ability of a battery reduces as the present draw boosts. This means that if your capacity is 3000 mAh for a constant 3 Amp current draw, then your capability will certainly be less than 3000 mAh if you draw a consistent 6 Amps or a consistent 30 Amps. I've seen a lot of descriptions of capacity that don't inform you this. You will often see it composed that if your battery's capacity is 3000 mAh, then that means you can attract 3 Amps for 1 hour, 6 Amps for 30 mins, or 30 Amps for 6 minutes. In general this is not the situation. In order to inform just how existing affects capability, you require to consider a lipo battery discharge curves. A lot of great battery datasheets will certainly show different discharge curves for different continuous current attracts. This number shows the discharge contour of an ONE, 1700 mAh, 35C battery (a lot more on what "35C" implies later). Each line stands for a various consistent current (42.5 A, 47.6 A, 51.0 A, etc.). This figure reveals us that for a given cut off voltage the discharge capability reduces as the current draw goes up. In this example, for a removed voltage of 3.0 V, the capacity at 1.7 A (1C) is 1700 mAh as well as I would estimate the capacity at 42.5 A (25 C) to be regarding 1630 mAh as well as the ability at 68.0 A (40 C) to be concerning 1460 mAh. So the 2 crucial points to remember concerning capacity are:. Ability informs you the quantity of existing that the battery can delivering for 1 hr. If you release your battery at greater currents than that, your ability drops. ( Note that Amp-hrs is not an action of power. Power is determined in Watt-hrs. If you presume that the battery is discharging at continuous voltage, you might determine power from that. However, as we discovered in the previous section, batteries do not release at constant voltage.).Like it? Share it! |