Best lipo battery is the part that you need to get the ultimate performance and better flight time for your drone or a multi-copter you should know how to choose a suitable drone battery.
As the other parts of a drone, these are also related to them.In this article talk about main things you need know before buy or choose a best lipo battery for your drone or quadcopter.
Lithium polymer battery.(Lipo)
With RC stuff we mainly use Lithium polymer batteries,There are few reasons for it and also there are few advantages and disadvantages.
Less in size
Easily can be damaged
How to Read Lithium polymer(lipo) battery data?
Choose perfect size(capacity)of lipo battery for your drone
In drone industry flight time is one of a key feature, so most people tend to use the largest battery.With a capacity it’s correct but higher your battery capacity-higher the battery weight.
mAh means – “Mili Amps Per Hour”,Simply it means If we got 1000mAh drone battery It gives 1A continuously for one hour.
So you should think twice before going with high capacity drone
battery because Battery weight is related with maximum takeoff weight of your drone
For an example think your drone –
* weight(without battery)is 800g
* motor-prop combination lift force is 2500g
So your maximum payload(Drone total weight) is 2500/1.8 = 1250g, this means your battery can be maximum 1250-800g = 450g. 450g is a lot but this will also include other components like (fc/fpv/etc..) so go online shopping and find out your battery weight.
For more details on find out what your maximum takeoff weight is for your drone have a look at my article on How to choose Motors & Propellers for your drone.And the other thing is the physical size of the battery, as depending on what type drone structure you are using, cuz your drone battery should fit properly to your drone.
Choose best lipo battery voltage (cell-count) for your drone
To produce more power to motors, first thing is you should read your motor thrust data tables If you don’t know what a thrust is then its best to check our our How to choose a brushless motor guide to learn some of the key concepts and what the numbers mean as I will make use of them in this tutorial.
If you got a battery to hand you can see there’s few cells(can’t see on 1s battery lol),
each cell has 3.7 volts.Adding more cell means adding more 3.7V. (Eg:3s-11.1v)
Higher voltage batteries are heavier cuz they contain more cells, however you’ll see some motors are generally more efficient and powerful when using higher cell (voltage),lipos but some of those batteries are slightly expensive and little bit heavier than others, so will need to choose what is best for your current budget.
NOTE – Also remember your other parts of drone (motor/ESC) are supporting your lipo battery voltage(cell-count).You can find out there input voltages from data sheets of em.
What is the best c rating?
If already know what motors and ESC we are using,By looking at the specs of your motors, in particular the thrust data tables you will be able to see what the motors maximum current draw when it’s max thrust.
As the above calculation my drone need 70A when it’s max throttle so above 3000mAh-3s-20c battery is perfect choice because it can drew 90A max this means it’s in a safe side.
Note – Always when you selecting c rate of battery it should be slightly greater than motor max current draw.
How to find correct discharge rate(c) for drone?
Take 820kV motor + 10×4.5 inch prop combination, If we use this combination for quadcopter drone, each motor take around 10 to 20 Amps to lift the drone, so all four motors takes roughly around 70A when it’s full throttle.As we discussed earlier 1000mAh battery can produce 1A for a one hour continuously, but we need about 70A from one second, There is the “c” rate comes to the game.
Guess you have 3000mAh : 3s : 30c battery –
Max continous Amp draw(A)= Battery capacity (Ah) x Discharge rate (C)
To find the maximum continuous amp draw, we first convert the 3000mAh to 3Ah, and multiply that number by 20C, to give a total continuous output of (3 x 30) = 90A
Choose best lipo battery connectors
Soldering battery to your drone is isn’t a good idea because It’s not much easier to charge,change and swap. But if you use a good connecter, It’s allows you to swap batteries easily and quickly.If you decide to build another drone in the future (Ohhh you’ll do!) you can use the same batteries.Common connectors are Deans , Tplug and XT60. Most popular one is T-plug but with my experience, better one is XT60 because it’s safer and more durable than t-plug.
Lipo battery safety
We discussed a lot about lipo battery but when you use it you need to know, how to use it safely because some times it’s extremely dangerous.
Do not over charge,
Always use a balanced charger
If your battery has more than one cell, the cells should charge balance cuz if you charge all cells from one voltage, those cells would be over charge.
Do not short it
As we talked earlier, lipo battery can gives massive current, so if it short it would be huge damage.
Do not damage cells
These stuff are (lithium and polymer) extremely flammable, so never damage to cells.
place in a safe bag (optional)
There is a bag (gray color) in electronic shops and online shopping sites, as called as “lipo battery safe bag” putting your battery this bag,helps to protect your other stuff from harms can occur from lipo batteries.