Li-Polymer Battery Basic Tag Information

Posted on 17 Sep 2012 by RC-Fever.com  

 

Due to the rise of brushless motor, also the technology upgrade of Li-Polymer. Li-Polymer battery supply becomes much more powerful and widely used. Let’s introduce the tag of Li-Polymer Battery and see what its mean, in order to help you to choose the most suitable battery.

The full name of Li-Polymer battery is Lithium Polymer Battery, short name is Li-Po. Here are some special features of Li-Polymer battery:

  • Low battery memory
  • Low self discharge rate
  • Light weight
  • High capacity
  • High voltage

Because of those feature, Li-Polymer battery become the most popular battery for helicopter.

Voltage:

One cell of battery is standard 3.7V. It can charge up to 4.2V and fully discharge to about 2.8V. Over charge or over use may lead to the damage of battery. You can see the voltage of Li-Polymer battery on the tag such as 11.1, 14.8 or 22.2. As one cell of Li-Polymer battery is 3.7V, you can guest how many cells does the battery connects in serial. (3.7V x 2 = 7.4V, 3.7V x 3 = 11.1V)

XSXP: You can see the XSXP on the battery, for example most popular 3S1P. S means the number of Serial, P means the number of Parallel. 3S1P means three cell batteries connect in serial and only one layer of parallel. Since many RC toys with voltage higher than 7.4V, therefore the Li-Polymer battery always connects in serial to result the high voltage. (1S to 3.7V, 2S to 7.4V, 3S to 11.1V) Then what is the means of 3S2P? It means two 3S1P batteries connect in parallel, therefore the voltage is still 11.1 but the capacity is highly increased.

Capacitance:

Such as 2200mAh, 2600mAh etc, let’s see what “mAh” means: m=mili (1 over 1000) A=Ampere (Unit of current) h=hour For example 2200mAh, equal to 2.2Ah, that mean if the battery use 2.2A to discharge, it can keep using for one hour, if the battery use 1.1A to discharge, it can keep using for two hours. Therefore for the higher capacity, battery can use for a longer time in the same current.

Number of C: It means the ability of release electricity, if the battery is 25C with 2200mAh, 2.2A x 25C = 55A, it means the battery can use 55A release electricity constantly. The higher number of C always more expensive as it needs special method to produce.

Weight: For the same battery specification, weight become a factor of choose. As flying hobby need to take much care on the weight. You can choose a light weight battery to decrease the whole weight or use a little bit high weight battery to balance the helicopter body.

Balance Plug:

It can use to measure the voltage and balance the voltage of each cell under charging process. The number of wire minus one is equal to the number of cells of the battery.

Power Plug:

The main power supply to helicopter is through this plug, there are different types of plug to suit the different maximum current, voltage or weight, such as T-plug, Banana-plug and JST-plug.

You can choose the suitable battery and charger from RC FEVER.