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Recommendations for lipo cutoff device Answered

i've been looking for a device similar to a battery alarm for 4s lipos that can cut off the power when any one of the cells drops below a certain voltage instead of just sounding an alarm, i've been told that i can get a bms circuit which should be able to do this and that i should try to find the best one i can but i don't really know exactly what to search for. can someone recommend a small and affordable bms please? i won't be charging through it as i have a separate balance charger, i want it purely as a cut off device for when the batteries are in use...



9 months ago

How about somethinglike this:
Would give you a regulated output voltage with low voltage protection.
Depending on the model even adjustable.
The "load" on this could be a relay or better SSR switching the actual load off.

But if size is no problem just check for adjustable battery eliminator.
Most are fixed for 12V car systems but you can get adjustable ones too.
Back in the day there were even electronics kits available for DIY to do just this.
But can't find a suitable circuit for high amps right now.


Reply 9 months ago

That little regulator looks ideal but it looks to top out at 9v output is there another one that can take a 4s lipo output (14.8v nominal, 16.8v max) or can this one be wired to bypass the regulator part and just use the cutoff part? I've tried searching for one with a higher output but so far can only find up to 12v...


Reply 9 months ago

As said some normal battery eliminators can be used.
They don't care about the output voltage and just cut all off once the set low limit is reached.
But they are quite bulky in comparison.
That is why I mentioned to use a SSR with the little one - they have no issues operating at 5V or lower.
Comes down to what you need just requires an additional part and some additional wiring.


Reply 9 months ago

I already have an alarm, what I need is a device that detects separate cell voltage in the same way as these alarms and cuts the power from the battery instead of activating a buzzer