Do you know the development history of RC lithium polymer batteries?

I believe that everyone is familiar with the lithium polymer batteries. His appearance makes the drone no longer have to rely on expensive and dangerous gasoline and methanol engines, and his affordable price and ease of use enable more and more novices to gradually Learn about the sport of model aircraft, and then discover its deeper and more professional side. First, I will explain the features of the CNHL 1000mah 7.4v 2s 100c lipo battery. 

1000mah 7.4v 2s 100c lipo battery, here is mainly lithium polymer battery, many people like to call it Lipo (from Lithium Polymer), in fact, its full name is Lithium Ion Polymer battery (Lithium Ion Polymer) This is a kind of The battery that can be recharged many times, his invention has revolutionized the aircraft model industry in the past ten years.

It basically eliminated the lithium-ion battery (Li-Ion), iron phosphate 1000mah 7.4v 2s 100c lipo battery ( LiFe), Nickel Metal Hydride (Nimh), Nickel Cadmium (Ni-CD), although these batteries now continue to play other roles in the model aircraft industry (for example, Nimh as a steering gear battery has the characteristics of long-term voltage maintenance), But lithium polymer batteries (we will call them 1000mah 7.4v 2s 100c lipo battery in the following) basically rely on the following three advantages to beat them and become the first choice of most mold friends.

Advantages of 1000mah 7.4v 2s 100c lipo battery

Advantage 1: 1000mah lipo battery has very light weight and can be made into any size;
Advantage 2: 7.4v 2s 100c lipo battery has a very large volume and a very high capacity ratio;
Advantage 3: The discharge rate of 1000mah 7.4v 2s 100c lipo battery is very high, which is very suitable for brushless motors that require large energy in a short time. 
These advantages may not be particularly obvious in the ship model and car model, but in the drone, its existence is directly equal to the difference between being able to fly or not. But 1000mah 7.4v 2s 100c lipo battery also has its weakness. for example:

Weakness 1: The price is still a bit expensive for Ni-MH batteries and Ni-Cd batteries, but with the increase of manufacturers and technological progress, prices are starting to decrease now.
Weakness 2: Short lifespan. An ordinary 1000mah 7.4v 2s 100c lipo battery has a maximum of 300 to 500 charging times from factory to scrap, but the upper and lower limits of this number will increase or decrease depending on how you charge and use, I will talk about it in future chapters arrive.
Weakness 3: Unstable use. Due to the high volume:capacity ratio of the 1000mah 7.4v 2s 100c lipo battery, the electrolyte it uses is very unstable, and a 1000mah 7.4v 2s 100c lipo battery can catch fire or even explode during charging and discharging.
Weakness 4: High maintenance cost. Compared with other batteries, if the 1000mah 7.4v 2s 100c lipo battery wants to go through the complete process of its life , the user needs not only to be careful when using it, but also to strictly follow the instructions to control the temperature of the storage room.

Construction and working principle of 1000mah 7.4v 2s 100c lipo battery

To further understand why the 1000mah 7.4v 2s 100c lipo battery has these characteristics, we have to talk about its structure and working principle.
We know that a battery has a positive electrode and a negative electrode, and the electrolyte is responsible for the exchange of lithium ions between the positive and negative electrodes.

Unlike Li-ion batteries that use liquid electrolytes, the 1000mah 7.4v 2s 100c lipo battery uses dry electrolytes, and the positive and negative poles are separated by a polymer paper like tin foil used in an oven, which is also a lithium polymer The fate of the battery name comes. Unlike lithium-ion batteries, which must be placed in an iron box, 1000mah 7.4v 2s 100c lipo battery can sacrifice thickness for area, or sacrifice area for thickness, so it is very suitable for the application of model aircraft.

The problem with this design at that time was that the exchange of lithium ions through the dry electrolyte polymer was not fast enough, which is why the 1000mah 7.4v 2s 100c lipo battery cannot be fast charged at ordinary room temperature. Of course, if you want to put it on a hot water bottle to charge, in theory, it can be charged quickly according to the temperature.

We know that a battery can be very underwhelming in the winter, and it will put out more power when it is warm in your pocket. In the same way, assuming that the external temperature remains unchanged, an aircraft using a 1000mah 7.4v 2s 100c lipo battery will find that it will fly faster after flying for one minute. This is precisely because the lithium ions inside the 7.4v 2s 100c lipo battery are positive and negative. Efficiency increases with cell chemistry after a period of pole swapping.

Of course, it is not to say that the hotter the better, one of the easiest ways to check the efficiency of the power unit is to check the battery temperature after landing. If the 7.4v 2s 100c lipo battery is warm, there is no problem. If the battery is hot, it means that the lithium ion is moving too fast. It is very likely that the paddle is too large and the motor cannot keep up.
Well, the above is the whole content of the 1000mah 7.4v 2s 100c lipo battery that CNHL brought to you today. I hope the introduction of this article can help you better understand the 100c lipo battery.
For more information on lithium batteries, please refer to the following:
The mystery of SBR floating blue in 5s lipo battery xt60 slurry
Do you know what is a soft pack 2s lipo battery 100c tab?