LiPo batteries (short for Lithium Polymer) are a type of rechargeable battery that has taken the electric RC world by storm, especially for planes, helicopters, and multi-rotor/drone.
They are the main reason electric flight is now a very viable option over fuel powered models.
RC LiPo batteries have four main things going for them that make them the perfect battery choice for RC planes and even more so for RC helicopters over conventional rechargeable battery types such as NiCad, or NiMH.
RC LiPo batteries are light weight and can be made in almost any shape and size.
RC LiPo batteries have large capacities, meaning they hold lots of energy in a small package.
RC LiPo batteries have high discharge rates to power the most demanding electric motors.
Unlike NiCad or NiMh; LiPo's have no "memory-effect".
In short, LiPo’s provide high energy storage to weight ratios, are capable of safe fast discharges, and can be configured in an endless variety of voltages, capacities, shapes, and sizes.
These benefits are important in any RC model, but for airplanes, helicopters, and multi-rotor they are the reason electric flight has become so popular.
Face it, electric RC cars and RC Boats have been around for decades; but it wasn’t until LiPo battery technology arrived on the scene that electric planes, helicopters, and multi-rotor started showing up and are now surpassing nitro and even turbine in terms of power to weight ratios.
Why? Because it simply takes way more power to get something airborne since overcoming gravity uses substantial energy over something that drives on wheels or floats on water.
There are a few down sides with RC LiPo batteries however; once again proving there is no perfect power solution.
RC LiPo batteries are still expensive compared to NiCad and NiMH, but coming down in price all the time.
Although getting better, RC LiPo’s don’t last that long when used in high demand applications like RC flight; perhaps only 100-300 charge cycles (much less if not cared for properly). The harder they are pushed, the shorter their life expectancy. If used very gently howerver, they can last over 500 cycles.
Safety issues - because of the high energy storage coupled with the volatile electrolyte used in LiPo’s, they can burst and/or catch fire when mistreated.
RC LiPo batteries require unique and proper care if they are going to last for any length of time more so than any other battery technology. Charging, discharging, storage, and temperature all affect the lifespan – get it wrong and a LiPo is garbage in as little as one mistake!