Some newcomers believe that the better the lithium battery brand, even the higher the price, the better it will be used. But this is often not the case. Even the best lithium battery will appear to be over-discharged. The reason for the over-discharge of the lithium battery is as follows: The use of the model lithium battery is the most critical. Now I am very satisfied with the 1800mah12c of 130 yuan that I don't know. The ESC automatically shuts off the battery according to the percentage of the battery voltage to protect the battery. For example, setting 65%, a 11.1v battery to 11.1x65% = 7.2v ESC will be powered off warning. But don't forget, this is calculated when the full charge is 100%. If the receiver is turned off (for example, debugging), then the bad luck will come, shut down midway, assuming 10v left, then turn it on again. At the time, the protection voltage of the ESC dropped to 10x65%=6.5v. The lower the more miserable... The consequences of this situation are very serious, that is, the battery is over-discharged. Although the battery voltage drops badly from the power can also be judged, or has been unable to fly early, but still very dangerous, will be over-discharged. Therefore, from the start to the end of the flight, this battery can not be powered off, otherwise it should be full and then re-flight. This is also mentioned in the manual of Ato's ESC. As for the live commissioning, you can set the throttle hold for safety.

How to use the HM lithium battery correctly? Please note that whether it is 3.7V for lithium or 1.2V for NiMH, it does not mean the voltage when the battery is fully charged. For lithium batteries, after the full charge, the voltage generally reaches 4.2V. I believe most people have mobile phone battery universal charger. You can see that the output voltage is generally 4.2V. Nickel-hydrogen fully charged can reach about 1.5V. In addition to the voltage, then the capacity and discharge rate. The capacity of the battery is in mah (milliampere hour) and the discharge rate is in C. In C number, simply said. 1C is different for different capacity batteries. 1C means that the battery can continue to work for 1 hour with 1C discharge. Example: The battery of 1500mah capacity lasts for 1 hour, then the average current is 1500ma, which is 1.5A, 1.5A is the 1C of this battery. If the above nominal 10C. The maximum discharge current of this battery is 1.5A*10=15A . That is to say that this battery is safe under 15A use. Another example is that 1000C in 1000mah is 1000ma, which is 1A. If the above nominal 15C. then the maximum discharge current is 1A * 15 = 15A, the maximum discharge current of this battery is also 15A. However, the above battery works at 15A, is 10C discharge, theoretically the maximum current work uses 60/10 = 6 minutes . While 1000mah works at 15A, it is 15C discharge. The theory can work with this current for 60/15=4 minutes. So relatively speaking, 1500mah, 10C battery to use a long time. So buying a battery to see the C number is not acceptable. A discharge battery having a small C number may be larger than a discharge having a large C number. This is related to capacity.

The full name of the remote control model lithium battery is a lithium polymer battery, generally referred to as a lithium battery or a lithium battery. This article uses the 11.1V remote control model lithium battery as an example to illustrate how to use lithium battery correctly. Usually, the 11.1V remote control model lithium battery is made up of three lithium batteries in series (3S1P), that is, the voltage of each cell is 3.7V. The voltage indicated on the lithium battery of the model, mobile phone, camera, etc. is called the marked voltage and is obtained from the average operating voltage. The actual voltage of a single-chip lithium battery is 2.75~4.2V, and the capacity of the lithium-ion superscript is 4.2V to 2.75V. The remote control model lithium battery must be used within the voltage range of 2.75~4.2V. If the remote control model lithium battery voltage is lower than 2.75V, it will be over-discharged, the lithium battery will expand, and the internal chemical liquid will crystallize. These crystals may pierce the internal structural layer and cause short circuit, and even make the lithium voltage become zero. The remote control model lithium battery voltage is higher than 4.2V, which is overcharged. The internal chemical reaction is too intense. The lithium battery will expand and expand. If it continues to charge, it will expand and burn. Whether it is over-discharge or over-charge, it will cause great damage to the remote control model lithium battery.

1. Charging
   1. 1-1 charging current: The charging current must not exceed the maximum charging current specified in the specification (normally 0.5~1.0C or below). Charging with higher than recommended current may cause battery charging and discharging performance, mechanical Performance and safety issues and may cause heat or leakage. At present, the 5C current-charged RC battery sold in the market is not recommended to use 5C charging frequently, so as not to affect the battery life.
   2. 1-2 Charging voltage: The charging voltage must not exceed the specified limit voltage (4.2V/cell), and 4.25V is the highest limit of the charging voltage for each node. (It is strictly forbidden to use direct charging, otherwise the battery may be overcharged, and the user will be responsible for the consequences of using the battery incorrectly).
   3. 1-3 Charging temperature: The battery must be charged wihin the ambient temperature range specified in the product specification, otherwise the battery may be damaged. When the surface temperature of the battery is found to be abnormal (refer to the surface temperature of the battery exceeds 50 ° C), the charging should be stopped immediately.
   4. 1-4 Reverse charging: Connect the positive and negative terminals of the battery correctly. Reverse charging is strictly prohibited. If the positive and negative poles are reversed, the battery will not be charged. Reverse charging can damage the battery and even cause heat, leakage, and fire.
2. Discharge
   1. 2-1 discharge current: The discharge current must not exceed the maximum discharge current specified in the specification (acceptance). Excessive current discharge will cause the capacity to drop sharply and cause the battery to overheat and expand.
   2. 2-2 Discharge temperature: The battery must be discharged within the operating temperature range specified in the data sheet. When the surface temperature of the battery exceeds 70 ° C, temporarily stop using it until the battery cools to room temperature.
   3. 2-3 over-discharge: Over-discharge will cause damage to the battery. The voltage of the single-cell battery should not be lower than 3.6V during discharge.
3. The storage battery should be stored in a cool environment. When storing the battery for a long time (more than 3 months), it is recommended to place it in an environment with a temperature of 10-25 ° C and low temperature and no corrosive gas. The battery is charged and discharged every 3 months during long-term storage to maintain battery activity and ensure that each cell voltage is in the range of 3.7 to 3.9V.