- #1
Flyboy
Gold Member
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- TL;DR Summary
- Can you parallel a Li-Ion and a LiPo battery?
I’m looking into electric RC aircraft, especially for endurance flights, and I keep running into a debate over what is the best battery design for a high-endurance/long range electric plane.
I have gathered that LiPo batteries are outstanding for high-power applications, such as racers, eVTOL, etc, where you need large amounts of power constantly.
On the other hand, Li-Ion batteries are increasingly used for high endurance FPV drones that are not running wide-open throttle, as the lower current output of the batteries is less of an issue, and the better energy density is advantageous.
I would love to use Li-Ion batteries for a future design where endurance and efficiency are the driving factors, but I am concerned about the limited current output, especially at takeoff. My thought was to parallel the main Li-Ion battery with a small LiPo battery that would provide the extra current needed for takeoff and climb out before switching to the Li-Ion, but I have seen no examples of this having been done before. Thus, I am wondering why it isn’t done. Obviously, there’s the issue of different cell voltages and current outputs, so directly paralleling them is probably not safe, but given the current state of solid state relays, it would seem to be a relatively simple task to make them separate circuits that would switch between them after you reach a safe cruising state.
I am not an electrical expert by any stretch of the imagination, so what am I missing aside from the additional weight and complexity?
I have gathered that LiPo batteries are outstanding for high-power applications, such as racers, eVTOL, etc, where you need large amounts of power constantly.
On the other hand, Li-Ion batteries are increasingly used for high endurance FPV drones that are not running wide-open throttle, as the lower current output of the batteries is less of an issue, and the better energy density is advantageous.
I would love to use Li-Ion batteries for a future design where endurance and efficiency are the driving factors, but I am concerned about the limited current output, especially at takeoff. My thought was to parallel the main Li-Ion battery with a small LiPo battery that would provide the extra current needed for takeoff and climb out before switching to the Li-Ion, but I have seen no examples of this having been done before. Thus, I am wondering why it isn’t done. Obviously, there’s the issue of different cell voltages and current outputs, so directly paralleling them is probably not safe, but given the current state of solid state relays, it would seem to be a relatively simple task to make them separate circuits that would switch between them after you reach a safe cruising state.
I am not an electrical expert by any stretch of the imagination, so what am I missing aside from the additional weight and complexity?