Trustfire batteries shutting down at high current draw



I am using the trustfire Li batteries. When I run all the 3 three thrusters at full speed outside the water, everything is fine. When I put the ROV in water and run just one thruster, at half the full speed, everything shuts down. When I run two motors, it shuts down at quarter the speed.

My conclusion is that the batteries are tripping at high current draw. Is there any solution to this, or a work around at least. I am using custom onboard electronics with a raspberry pi. I isolated the power supply for the motors by putting a separate lithium ion batteries to power the onboard electronics. The 6 trustfire batteries (3+3 in parallel) are only powering the motors.

I saw the new recommended batteries. Is that the only way ahead or can I fix this issue somehow with my trustfire batteries.

Any help in solving the problem would be great. Thanks.


Hey Prassana,

We've started recommending the other type of batteries exactly for the reason you describe, so switching to them is probably best. The reason your batteries shut down is because they have a built in circuit board (located at the "-" end of the battery, I think) that turns off the connection between the "-" plate and the rest of the battery when the current gets too high.

Theoretically, it would be possible to remove this circuit from each battery which would keep the battery from doing this, but please keep in mind that the reason those circuits are there is to protect the battery and to keep it safe. If you did this operation, it would be very easy to short the battery out which could be dangerous, and moreover, modifying the battery in such a way may make it more possible for the battery itself to become dangerous if used beyond its specifications. Do this at your own risk only if you understand the precautions, and good luck!