Lithium-polymer (Li-Po) and lithium-ion (Li-ion) batteries are both types of rechargeable batteries that are commonly used in radio-controlled (RC) vehicles such as cars, planes, and drones. They both use lithium-ion technology, but there are some differences in their construction and performance.

One key difference between Li-Po and Li-ion batteries is the type of cathode material used. Li-Po batteries use a polymer cathode, while Li-ion batteries use a metallic cathode. This difference in cathode material can affect the performance and lifespan of the battery.

Li-Po batteries tend to be lighter and have a higher energy density, meaning they can store more energy in a smaller package. They also have a lower internal resistance, which can allow for more efficient power delivery. However, Li-Po batteries can be more sensitive to overcharging and can be damaged if not properly handled.

Li-ion batteries, on the other hand, tend to be more robust and have a longer lifespan compared to Li-Po batteries. They are also less sensitive to overcharging and can generally withstand more abuse. However, they tend to be heavier and have a lower energy density compared to Li-Po batteries.

Overall, both Li-Po and Li-ion batteries have their own advantages and can be suitable for different applications, depending on the specific requirements of the RC vehicle.