A Revolution in RC Battery Technology

The revolution motors was accompanied by a revolution in battery technology. The energy density of modern lithium-polymer (LiPo) batteryies, combined with the amount of power they can provide at very cheap prices, has opened the door to a new class of aircraft. With this comes a warning: Lipo batteries can catch fire in very dynamic ways from charging, physical damage, or a change in the wind. A great idea is to have a collection of clay flowerpots in which to store and charge batteries. Don't let the batteries get hotter than 120 degrees Fahrenheit or freeze.

A common way to destory a battery is to leave it plugged in to the speed control when the plane is not being flown. If the battery is discharged too deeply. It will destroy the battery.

At the Brooklyn Aerodrome, we have settled on the 1800-milliamperehour (mAh) or 1.8-amperehour two-cell battery pack because such battery packs are cheap and are around the correct weight to balance the Flack. For the more creative aircraft, such as the Bat, we double up battery packs for nose weight and will add lead tire weights if needed. It is easier to have a standard size and work around it than to have varying capacities that inevitably will have you at the flying venue with the wrong-sized battery pack. The other considerations around batteries are the speed-control connector and the balancing connector.

Recommend LiPo Battery pack

Genstattu.com has the least-expensive battery packs historically, and they perform okay. I use very high-quality Thunderpower packs that have not puffed out despite being five years old, but that is the difference between an $8 to $9 battery and a $30 battery. I suggest going cheap with low expectations. Lots of brands are available, but try to buy from a U.S. warehouse to minimize shipping costs and transit time.

3S Gens Ace 5000mAh

Currently, I use the Gens Ace Gens Ace 3s lipo 1800mAh 20C (U.S warehouse) at $8 to $9. This battery lasts about one to two years if treated well and has shown itself to be crash-tolerant. It has a JST-XH connector for charging and a male XT60 connector for powering the airplane. Be mindful of these connectors when buying chargers, and you will have to buy and solder a male XT60 connector onto your speed control.

Alternative Batter Packs

Any two-cell LiPo pack with a 20C or greater rating will do. BP Hobbies offers the Cheetah Packs 7.4V lipo battery 5000mah 35c LiPo battery at $16 with JST-XH connectors for charging and Cheetah 4.0-mm controller connectors.

Be aware that lithium-iron-polymer (LifePo) and lithium-iron (LiFe) batteries are now being sold that look very much like LiPo batteries but differ in a few ways. They have a lower voltage (6.6 volts versus 7.4 volts for LiPo), so if you go with these, be sure to go on ghe higher end of kilovolt ratings for the motor - 1800 kilovolts is about right - and consider using a 10-inch prop where I have been recommending a 9-inch prop. These batteries also will require a charger that is designed for them. A major advantage of LiFePo batteries is that they are less likely to catch fire.