- Jan 23, 2009
- Reaction score
This comment and my opinions applies mainly if you are using the battery to also power your electronics.John’s comment about not using battery protection circuits is at odds with what I’ve seen others do, so more elaboration on that subject would be useful. As a circuit designer, that would certainly provide a lot more insight into the pitfalls an average user might not consider.
- If your battery protection circuit activates it will result in a brown-out or reset of your flight computer.
- You should not prioritize the protection of your battery over the protection of your rocket.
- A well implemented overload protection circuit should only be used if your electronics actively controls the current to the load. Thus the overload protection will kick in only if a failure of your primary method of current control occurs. Your electronics and power supply is a system.
- Most altimeters do not control the current to the load. The instantaneous load current is unknowable.
- The battery protection circuit introduces an addition point of failure in your power chain. (I have recently bought a new 18650 battery pack with a defective protection circuit.)
- Rocket ignition conduction time is usually very short, often less than 1s latch time. Most Lipo batteries can safely deliver current well in excess of the protection circuit rating for such a short time. The protection circuit is not needed and can only do harm.