In the context of RC lipo batteries, the values 25C, 30C, 50C, and 80C refer to the C-rate, which is the maximum discharge rate of the battery. The C-rate determines the battery’s discharge capability at a fixed capacity, directly impacting the performance of your RC models. If you want to learn more, please continue reading this article.
Choosing the Right C-Rate
With years of technological advancements, the market now offers lipo batteries with increasingly higher C-rates. This crucial parameter has become a standard for evaluating the quality of a battery in the RC hobby world. A higher C-rate can enhance the speed and responsiveness of RC models. Therefore, 80C is better than 50C, which is better than 30C, and so on.
However, the production costs also rise with higher C-rates. So, when choosing a battery, you need to consider what C-rate is most suitable for your needs. For RC racing cars and bashing off-road vehicles, a higher C-rate is definitely preferable. However, some slower-moving RC models, like crawlers, do not require high power output. For these, a C-rate of 25C to 50C is sufficient to provide the necessary power. In practical use, they benefit more from extended running and climbing times, thus preferring higher capacity lipo batteries.
The Truth About C-Rate
If you are a beginner in the RC hobby, you might not realize that the 25C, 30C, 50C, and 80C values claimed on batteries are not always the actual maximum discharge rates. Only with professional checkers and analyzers can you measure the true maximum discharge rate. Therefore, in real-world use, these values tend to be lower. For example, a battery advertised as 80C might actually have a real discharge rate closer to 20C.
Calculating Current
Based on the battery’s capacity and C-rate, we can calculate the required burst discharge current, continuous discharge current, and charging current.
- Burst Discharge Current = Battery Capacity (Ah) x Discharge C-rate (C)
- Continuous Discharge Current = Burst Discharge Current x 1/2
- Charging Current = Battery Capacity (Ah) x Charger C-rate (C)
Using the battery’s burst discharge current, continuous discharge current, and voltage, we can determine the appropriate battery for the ESC and motor to achieve optimal performance. This helps us avoid issues of insufficient power or excessive power.
