A123 Battery Cells For Your Radio Control Model Airplane
Electric model airplanes have been in existence for roughly three decades. A big problem in the early days was battery energy density. Quite simply, they only weighed too much for your level of juice you could get out of them. This case has improved dramatically in recent years using the coming of Li-Poly cells, but battery power pack for a larger model can simply cost big money. The arrival of electrical cars, including the Toyota Prius has spurred a whole lot of research into new battery technologies. In this article, I am going to describe a substitute for Li-Poly batteries that gives intriguing possibilities.
RC Lipo Batteries
A123 Systems produces Lithium-Ion Nanophosphate cells. These cells possess a nominal voltage of 3.3 volts and can withstand continuous discharge rates of 30C. They may be safely discharged as a result of 2.0 volts. The voltage remains fairly constant with the discharge cycle, nevertheless they do have a sharp drop-off by the end. Expect 300 cycles before you notice any decrease in capacity while at 1,000 cycles you should have 75% of the original capacity. They’re very safe and secure. Overcharging or higher discharging is not going to cause an outburst and will have little effect on living from the battery. Balancing cells if they are charged continues to be a good idea, although not absolutely required. They could be charged soon after use within Quarter-hour.
The cells can be purchased in two sizes. The initial M1 cell features a capacity of two.3 Ah and weighs 70 grams (2.47 oz). A newer, smaller size can take 1.1 Ah and weighs 40 grams (1.41 oz).
The primary source for A123 M1 cells has been DeWalt 36-volt portable power-tool energy. Each pack contains 10cells. I got myself two of these for $100 each through Ebay. The costs appear to have increased recently towards the $120-$130 range. Single cells can also be purchased online for $15 from a growing number of vendors. You will find two smaller cells in the Black & Decker VPX battery pack which costs about $15. Small cells can be had for $12.50 each.
There are many Li-Poly chargers that support or can be modified to guide the charging of those A123 cells. Due to the sharp voltage drop-off when discharged, you are probably more satisfied employing a timer once you fly. Or else you need your ESC to close off the motor when 2.0 volts per cell is reached.
Main point here? These cells provide you with 70% the vitality density of Li-Polys for approximately 45% with the price. For most of us, that’s a good trade-off. They are extremely safe and is charged in 15 minutes. In the event you purchase half as much battery packs due to the shorter charge time, then they be a far better value.