| Lithium Polymer Batteries is the favorite power source | | | | each charge and would also result in a diminished |
| of electric radio-controlled models. They are relatively | | | | performance of the battery pack. |
| cheap, light, and hold lots of power. However, many | | | | A balance charger eliminates any unbalanced-cells |
| new hobbyists may have some enquiries as to their | | | | symptoms of a battery pack by charging each cell |
| operations. | | | | individually; making sure that the cell's voltage remain |
| Here are three frequently asked questions about them. | | | | balanced at the end of each charge. In essence, |
| 1. What is Cell Balancing? | | | | balance charger lengthen the life of the battery back |
| Lithium Polymer batteries usually come packaged as a | | | | and maximizes its performance as well as keep the |
| pack of more than two individual battery cells. For | | | | pack stable and safe to operate. |
| example, electric RC helicopters use 3-cell packs. Each | | | | 2. What is C rating? |
| of these battery cells has a nominal voltage of 3.7v; | | | | A lot of radio-control fliers quickly grasp the meaning |
| which means that each cell can operate when it | | | | of most of the battery-associated acronyms but one: |
| maintains its charge between 3.0 to 4.2v. To go above | | | | the C rating. In fact, many experts have tripped over |
| or below or below this range can damage the cell and | | | | themselves trying to explain it. However, I've heard a |
| render it useless, or worse, become dangerously | | | | graspable explanation of it from an old Chinese battery |
| unstable and explode. | | | | manufacturer/expert very recently. Which is: The "C |
| While the battery is in usage, the power drawn out of | | | | Rating" is the number which you multiply to the |
| each cell is not equal. Therefore, at the end of each | | | | capacity of the battery to get its discharge rate. |
| flight, the cells in the battery will be left out of balance. | | | | Still confused? Basically, a 1000 mAh battery rated at |
| A non-balancing charger will stop charging the battery | | | | 1C will provide 1000 mA of power for 1 hour. On the |
| pack once the voltage of the overall pack is full | | | | other hand, if the same pack was rated at 2C, it would |
| without paying any attention to each cell. This causes | | | | provide 2000 mA of power for 30 minutes. |
| the battery to be more and more unbalanced with | | | | 3. How fast can I charge a pack? |