Hubsan X4 FPV Quick Manual page 3

Warning! Over Discharge:
These Lithium batteries must be used within the given voltage range of 2.75v - 4.35V. If the voltage of a single
cell is lower than 2.75V, that causes an over-discharge. In such cases the lithium battery cell will start to swell
up and the internal chemical liquid will crystallize. These crystals may pierce the internal structure layer and
cause a short circuit, or make the lithium battery voltage zero. Or in some cases fire and explosion when trying
to charge such damaged cells.
Never over discharge the battery:
If we look at the discharge curve of the battery, at the beginning of the discharge / use, the voltage drops
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relatively quickly, but when the battery cells are discharged between 3.9V and 3.7V, the voltage does not
drop too fast. Once it drops to 3.7V per cell, the voltage drop speed will increase. If continue to use battery,
it can lead to over discharge, which can damage the battery, may cause the battery to stop working, and
cells may start heat up and swelling, if the voltage drops too low.
Take extreme cautions and never over discharge the battery. You should not fly the drone and or use the
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battery if its about to over discharge. Always keep an eye on your Drone App prompts to return to home
and or immediately land in case of battery levels dropped to critical low.
Avoid flying in extreme temperatures. To give batteries the longest life possible, follow the manufacturer's
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instructions for flying, which should include a safe temperature range and a lowest acceptable discharge
level.
Don't drain the battery too fast. Flying at full throttle for long periods—which can be preferable for some
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flying purposes, such as racing and agility—can also drain batteries so fast that they enter a dangerous
process known as thermal runaway, where the materials inside the battery heat up and cause chemical
reactions that prompt the battery to heat up even more.
Discharging and Storing the batteries
If you are not going to fly your drone for more than 7 days, you must discharge your drone batteries to
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storage level (3.8v per cell) and then store them safely. If you store a fully charged battery for more than 7
days, it will damage the battery cells in the long run. You may encounter swelling up battery and or a
battery that does not fully charge and or does not perform as it used to.
The new digital batteries of Hubsan Zino 2+ Drones automatically will discharge over time and each cell
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will get down to 3.8v (storage level) but Zino Pro series drone batteries must be manually discharged. You
can fly your drone and just hover it until battery is at 50% - 60% level and then safely store the battery.
The battery should be stored in a cool, dry environment. When storing the battery for a long time, it is best
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to put it in a sealed bag or a sealed battery fireproof explosion proof bags. The recommended ambient
temperature is 10~25℃, and it is dry and non-corrosive.
Hubsan Aerial Filming Drone - Fly with your Dreams
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