Lithium Polymer or LiPo batteries can be used in the drones themselves and their controllers. They can be low discharge rate or high discharge rate (the amount of Amps they can give in a small amount of time). The higher performance drones, such as racing drones, benefit greatly from high discharge. Lithium batteries are rated in a “C” system where the number of “C” is multiplied by the number of Amp Hours in a battery = the number of amps a battery can draw. Many of the suggested LiPo batteries will be in the 75 or 100C range and can deliver.
When working with Lithium Polymer batteries the safe voltage to stop using them and land your craft at is 3.7v per cell. So for a 3 cell, 11.1 volts, a 4 cell, 14.8, and so on. Going below that voltage takes the risk of damaging the LiPo and when recharging from a voltage below 3.7v per cell, can cause a fire. Keep in mind, when you are flying racing drones that your battery voltage is the best indicator of when to return home. It is normal for a battery to sag below the safe voltage during extreme maneuvers but a moment of hovering or slow forward flight will show you a more realistic voltage figure. Assuming you are flying a 4 cell battery (16.8v when fully charged 4.2v x 4) you may see voltages as low as 13v during punchouts but the battery will return to a much higher voltage after the maneuver. When the battery does not return to normal voltage or the voltage shown in your OSD is less than 14.8v ( for 4s packs ) it is time to come home and land.
**Always keep a battery checker handy to test battery voltage, they are cheap insurance against storing a bad LiPo in your vehicle or home where it can cause a fire**
LIPO CELL COUNT
Drone batteries range anywhere from 1S to 6s. The “S” stands for Cell Count in SERIES Lithium Polymer batteries are all 3.7v nominal per cell. We know thats alot of math so heres a chart to help you understand. These voltages are nominal which means that it the bottom voltage and the safe voltage to have your batteries rest at after flying or when you put them away for an extended period.
1S – 1Battery in “Series” this battery would be 3.7 volts x 1 or 3.7 volts
2S – 2 Batteries in “Series” this battery would be 3.7 volts x 2 or 7.4 volts
3S – 3 Batteries in “Series” this battery would be 3.7 volts x 3 or 11.1 volts
4S – 4 Batteries in “Series” this battery would be 3.7 volts x 4 or 14.8 volts
5S – 5 Batteries in “Series” this battery would be 3.7 volts x 5 or 18.5 volts
6S – 6 Batteries in “Series” this battery would be 3.7 volts x 6 or 22.2 volts
Depending on the size and speed of your drone you may choose anywhere from a 1s for very lightweight indoor brushed drones all the way up to 6 cells for the maximum power but also maximum weight and flight difficulty. If you met a Table 5 pilot flying outdoors it is likley that you witnessed a pilot flying 4s, 5s or 6s LiPo batteries. As the hobby slowly shifts to higher voltages the 5s and 6s batteries become more common and eventually pilots settle into a voltage they like and pilots tend to amass large quantities of their battery of choice.
There are 2 main battery types used in the drone hobby.
Lithium Iron or LiFe batteries are almost never used in the Drones themselves due to the low discharge rate. A typical LiFe battery pack will have a discharge rate of 20-25C. LiFe batteries have a low discharge rate so they last quite a while longer. Transmitters (controllers) can benefit from LiFe as the transmitters don’t require a lot of power therefore lasting a long time and we all want to keep flying and not stop to replace. Keep in mind that the nominal voltage of Lithium Iron batteries is also considerably lower and they cannot be charged alongside Lithium Polymer packs.
Note: if you are replacing your controller batteries often, a LiFe battery could be a huge improvement. See our tips, tricks, and suggestions page here