I am trying to build a small robot powered by 18650 cells and it was supposed to use a magnetometer as part of its navigation. I don't get sensible answers from the magnetometer even after trying to calibrate it. 18650 cells use a lot of nickel which is ferromagnetic also the frame of the LCD is ferromagnetic.

Are there any non-magnetic 18650 style cells available?

 

Won't the EM field produced by any current draw be a problem in itself, even if you could find a non-magnetic battery?

 

I could perfectly well read the magnetometer while high current stuff is switched off, principally the motors, so I don't think fields from current flowing will be a prpblem.

 

Hello,

Can an other shape for the battery be used?
Then have a look here:
https://www.powerstream.com/non-magnetic-lipo.htm

Bertus

 

My guess is that your problem is elsewhere. Magnetometer based compasses are used in LOTS of applications.

You might try to confirm your hypothesis regarding the cause by running power to your project via coax from some distance away and see if the problem is significantly diminished.

 

Are there any non-magnetic 18650 style cells available?

I'm far from an expert on these cells but I have seen a lot about them - eg. reviews that separate the real ones from the fraudulent knock-offs - and have never encountered one that mentioned magnetic properties. I suspect the "can" material is pretty uniform.