- Voltage S
- Current Capacity
- Discharge Rating C
- Weight and Dimensions
- Battery Performance
- Charge LIPO-Battery
- Battery Monitor-Alarm
- Safety Instructions
LIPO (Lithium Polymer Batteries) One of the important Modules in any field related to electronics especially in RC Aircraft, RC Trucks, RC Cars, RC Boats and RC Tanks, in addition, it’s used in industries. it’s the basic unit to provide the system with the necessary electrical power, in this tutorial we will study the properties and components of LIPO Battery. the reason we chose this type of batteries is its availability and excellent electrical properties it works for long periods and resists heat and gives high Power, it’s the first amateur battery to suit most projects. this battery gives a lot of different features and user choices but within the parameters that we will study now. choice of the LIPO battery depends on the application used, for example when choosing the motor should choose the appropriate battery properties (Voltage, Current, etc) don’t worry about it, its save but follow the instructions carefully.
All LIPO Batteries have a basic classification according to the number of cells ‘S’ each cell has a standard nominal voltage equal to 3.7 V. Maximum charge per cell 4.2 V and not less than 3 V, but We classify by nominal value. the picture below shows that this battery is equal to its voltage 2S, each cell has 3.7 V so 2 * 3.7 = 7.4 V, Some companies write on the battery 2S or 7.4V or together like green box in the picture.
The following table shows the voltage of the different cells
If you have a tank of water, water represents the current. usually, the current value is the largest number on the battery and measured in mAh which means (Milliamp/hour) or Ah which means (Amp/hour). Current capacity is an important factor to provide the longest possible run time. The capacity rating: 5000mAh is 5000 milliamp/hours or 5 Amp/hours. that is the amount of energy the LIPO-Battery can use. so this battery will give 5 amps of current for one hour. Or 10 amps for a half-hour (30 minutes) , or 20 amps for 15 minutes. The following picture in the green box shows the current capacity on the battery.
Discharge Rating C
Discharge Rating is the amount of power the LIPO-battery can supply your electrical system. the ‘C’ rating is a multiplication of the current capacity. For example, the previous battery: A 100C battery can discharge at 100*5000mAh which is 5000,00Ah or 500Amps. this number is important to consider, The milliamp per hour divided by 1k or 1000, times the C rating, equals to the maximum continuous discharge amperage the battery is capable of sustaining. mah/1000*C then 5000mah/1000*100c = 500 Amps.
The equation is mAh / 1000 * ( C rating) = amps. For example, If you had a 3000mAh LiPo with a charge rating of 3C you would not want to charge the battery at a rate of more than 9 amps. Remember this point: To maintain battery life for a longer time, use a slow charger. The following picture in the green box shows the Discharge Rating on the battery.
Weight and Dimensions
Weight and Dimensions of the Lipo Battery important factors to pay attention to, you may find voltage and current specifications at a low price but you may be surprised by the weight of the battery. So give weight to the importance of buying the battery, a few grams or plus Length may make the plane can not fly or sink the boat and so on. Some batteries weight 50 grams and some more than 600 grams depending on internal characteristics. Always remember to calculate the battery weight from the total weight of your project, you can find out the battery weight from the store you are using.
LIPO Battery provides connectors which in turn connects electronic parts tightly without the need for soldering. there are many types and sizes you can see them here: RC Battery Connector Types.
How does temperature affect LIPO battery performance? In fact, the LIPO battery is affected by high temperature or low-temperature environment. Let’s take a look at the following chart: charts credit to genstattu.
We can see that during the battery used the ambient temperature has an impact on the performance of the battery, low heat leads to reduce battery efficiency. The optimum operating temperature level for these lithium batteries is 0 to 35 ℃. The low-temperature environment will reduce the activity of lithium ions, the LIPO battery discharge capacity will be weak, and the usage time (lifetime) will be shortened.
Charging the Lipo battery is not the same as any battery it’s needs a special charger has the ability to perform balanced charging, Lipo battery chargers are capable of charging the battery according to the charging criteria and appropriate voltage 3.7 per cell, when installed with a battery has 3 cells each cell will be charged individually the charger will give you an indicator of the status of each cell in the battery. when using a battery with more than three cells, make sure you buy a charger that supports more than three cells, the LIPO Battery charger must give the necessary output Power to charge your Battery. Some chargers feature fast charging but believe me it will really destroy the battery. The following pictures show some famous chargers:
I want to tell you about a cheap but great tool that it is a Mini LiPo Batteries Monitor use For fast voltage checking This tool can check cells especially if you are out of the house and the charger is not near you, It has an alarm that alerts you if the voltage is less than 3V.
Here I put you the most important instructions to handle the Lipo battery safely without getting any trouble:
- Avoid fast charging as much as possible because it reduces battery life.
- Use the correct battery in applications such as Motor, lighting systems, etc.
- Never open the battery.
- Buy a good quality battery with a hard plastic cover.
- Stay away from people who say ways to increase battery power because it’s destructive.
- The LiPo Battery stays safe if used properly.
- Avoid use at very low and very high temperatures.
- Be sure to choose a good charger.
- When you leave the battery for a long time, be sure to charge percent between 40-50% , This is called Storage mode in chargers.
- Keep the battery away from any combustible material and store it in a special container.