LiPo “C” rates explained

A LiPo battery (Lithium polymer battery) has multiple cells. each cell delivers around 3.7 Volts.
A 3S LiPo would therefore supply 11.1V.

Apart from the cells, you also have a ‘C’ value.
You can see any kind of C value on a LiPo like 25C or 40C

So, what does the C tell?
C rating is a rating of how quickly energy can be discharged from a battery

Some examples.

1000mah 10C battery will “safely” discharge continuously at 10A
1000mah 15C battery will “safely” discharge continuously at 15A
1000mah 20C battery will “safely” discharge continuously at 20A

2000mah LiPo at 10c would safely discharge at 20A
3000mah LiPo at 10c would safely discharge at 30A
And so on.

A 3S 2200maH 40C LiPo pack will get you: 2200mAh x 40C = 88.000 mAh discharge rate 88.000 mAh / 1000 = 88 Ampere constant discharge rate.

So, a 2200mAh / 40C LiPo can only handle an Ampère draw of 88A at max. The C rating is important when it comes to choosing a battery for a drone, motors draw high amounts of current (amps) and it is very easy to choose a battery that is not properly rated for our current draw.

The most important difference between batteries with a different C-rating, is the fact that the higher rated batteries suffer less from voltage drops under load.
That means that when you demand the most from them (during lift), the higher rated batteries are able to deliver the amperage at a higher voltage, so that means more power (amps x volts = watts which equals power).

Putting LiPo’s in parallel or serial will not change the C rating!
Parallel = double the amps. (longer flying times)
Series = double the voltage.
There is no difference between 2 x 1500mAh 20c batteries in parallel and 1 x 3000mAh 20c battery. Either can supply a total of 60 amps constant.

Too low c rating can cause damage to the LiPo, and is not recommended.
On the other hand, a higher C rating LiPo in your drone could extend flying times, especially in cold weather, fitting a higher C LiPo could compensate the shorter flying times due to the cold. a Higher C rating LiPo is also recommended if you are planning to fly with payloads (let’s say a 360 camera), as described above, a higher C rating can deliver the amperage at a higher voltage, so the drone can carry the load easier, and longer.

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