What is LiPo
A lithium-ion polymer (LiPo) battery is a rechargeable battery of lithium-ion technology using a polymer electrolyte instead of a liquid one.
Most Important
It can be very dangerous
Specifications
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Configuration: 6S1P / 22.2V / 6 Cells
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Minimum Capacity: 1200mAh
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Discharge Rate: 150C
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Max Burst Discharge Rate: 260C
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Net Weight(±20g): 197g
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Dimensions:78mm x 40mm x 34mm (L x W x H)
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Charge Plug: JST-XHR
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Discharge Plug: XT60
1S
3.7v
1000mah
3S1P
Series
11.1v
1000mah
1S3P
Parallel
3.7v
3000mah
Cell Configuration
A LiPo cell = 1 cell = 1S
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A lipo cell nominal voltage is 3.7V.
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Fully charged is 4.2V per cell (HV lipo can be charged to 4.35V).
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Should never be discharged below 3.0V.
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Storage voltage is 3.8V per cell.
By connecting more of these in series, the voltage can increase to 11.1V for a 3 cell battery.
By connecting more batteries in parallel the capacity can be increased.
1S
2S
3S
4S
5S
6S
Voltage
3.7V
7.4V
11.1V
14.8V
18.5V
22.2V
FULL
4.2V
8.4V
12.6V
16.8V
21V
25.2V
Landing
3.5V
7V
10.5V
14V
17.5V
21V
0%
19.8V
16.5V
13.2V
9.9V
6.6V
3.3V
Voltage directly influences the RPM of the electric motor (brushless motors are rated by kV, which means ‘RPM per Volt’). So if you have a 3500kV motor, that motor will spin 3,500 RPM for every volt you apply to it. On a 2S LiPo battery, that motor will spin around 25,900 RPM. So the more voltage you have, the faster you’re going to go.
So the number of cells is what defines the voltage of the battery. Having a higher voltage means the battery can provide more power to drive bigger motors, however more power does not necessarily mean the battery will provide energy for longer, that is defined by the battery capacity.
Battery capacity is measured in Ah, or Amp-hours. As the name suggests this means how many amps the battery can deliver in an hour.
For example, a 12V lipo battery with a capacity of 1000mAh can deliver 1A to a 12-volt device for one hour.
H = mAh / 1000 / A
Watt-hour (Wh):
Another way to measure the capacity of the battery is in Watt-hours (Wh). Wh is calculated by multiplying the number of Amps with the battery voltage.
For example, a 12V1000mAh has a capacity of 12 x 1 = 12Wh.
W = V x A
Generally, a larger capacity pack may give you longer flight times but being heavier it will adversely affect performance.
It's also influenced by the speed, the more quick you can flying your plane, the less time your flight time is. Because high speed means you need more power to drive your plane or others, so your power lost quickly.
Voltage (V) is the pressure that pushes charged electrons (current) through an electrical circuit.
In brief, voltage = pressure, and it is measured in volts (V).
Current (I) is how much electricity “flows” per second in a circuit.
Ampere (A) is the international unit used for measuring current.
1 A (Ampere / amp) = 1000 mA (Milliampere)
If the number of amps goes up, then current flowing through the device per second also goes up. An electrical device usually works on a fixed voltage, but the amount of amps it draws can vary depending on.
e.g. Half throttle draws 15A. If go faster with FULL throttle, now pulls 25A. The voltage has remained the same but the number of amps has gone up.
Voltage is the cause and current is its effect. Voltage can exist without current. Current cannot flow without Voltage.
Watt (W) is a unit of power. This is the amount of energy consumed by a device and therefore an indication of how powerful it is. This goes up when the number of amps also goes up.
Discharge Rating
Discharge Rate ("C" Rating) is simply how fast a battery can be discharged safely. A battery with a discharging rate of 95c, that means you could safely draw it at the 95 times more than the capacity.
95C = 95 x Capacity (in Amps)=95*1300mAh=123500mAh=123.5Ah
Higher “C” rating means your thing can get a higher burst in a moment. But the disadvantage of the high “C” rating is it may get heavier and it may more expensive.
Battery Connectors
There are different RC battery connectors’ types.
All the connectors have the different range of current and they also vary in different applications.
There are two types of connectors:
Power connector is used for high current use.
Balance connector is used to balance the individual cell’s voltage.
Safety
LiPo batteries last for more than hundred cycles, so proper charging and usage is recommended.
If try to attract more current from a battery beyond its capability, its voltage capacity will drop down soon. It will also lead to destroying chemistry content of the battery which can even reduce the time span of the battery.
If the Internal Resistance is more, the battery will swell up a little due to oxygen build up. This is the battery’s way of telling you that its end is near, premature or timely,
Charging
It’s recommended to charge LiPo at 1C for safety. That means for a 1000mAh LiPo, you should it at 1A (1C x 1000mA).
Series charging is the better option, balance charging plays a key role here as they charge each cell up to a safe level.
Parallel battery charging is highly dangerous as it doubles the capacity of the batteries and it is important to maintain the voltage of every individual cell connected in the series.
If two batteries of exactly the same properties with identical qualities are put to parallel charging, then it is fine. But we would not be able to differentiate in them, there will be a significant increase in the chances of overcharging of the batteries.
Storage
Should not be stored fully charged because they might get damaged.
Never storage Batteries to extreme temperatures or direct sunlight. The battery should be stored within -10℃ ~ 45℃ range environmental condition. If the battery has to be stored for a long time (Over 3 months), the environmental condition should be:
Temperature: 23±5℃
Humidity: 65±20%RH
The voltage for a long time storage should be 3.6V~3.9V range per cell
Always disconnect Batteries when not in use and store Batteries in a non-conductive and fireproof container.
Never alter, puncture or impact Batteries or related components.