The Airwheel Q3 260wh has two paralleled 130Wh battery packs, each with its own BMS (battery management system). Even this setup, if not shunted, is still dangerous, tatane33 has had a fractured jaw because of a sudden power cut on his Q3. Peppuzzo has shunted both BMS for added security. He wants a fail safe wheel, which is understandable even if shunting just one BMS is probably enough.
Source peppuzzo of http://forum.electricunicycle.org
Airwheel Q3 clone
Q3 clone, before and after the shunt. Note the manufacturer has make a bad wiring, soldering together C- and P-, which means the BMS has no overcharge protection !!
Source smallexis from trottinetteselectriques.heberg-forum.fr
Shunt directly B- to P- instead of shunting the mosfets. Very easy to do.
T1 and X1 are not easily distinguishable. When in doubt, shunt only the two middle Mosfets.
I had no idea what shunting was until I came to this page. What wire do I need to use to do the shunt? And At the ends, is that just soldering wire?
I have an X3 btw. I’m assuming the B- and P- are far enough that I have to do the shunt with a wire?
Yes, soldering a wire is all is needed to shunt and secure your X3. I use a thick wire, eg from a kitchen appliance.
Would a iphone charging wire work? Btw, thanks for this write up!
No, too thin.
Use a wire as thick as the thickest wire in your wheel.
Hi, in the X3 isn’t possible to do the same as the X8? if not, can you publish a pic. Just to be sure how it’s done?
Unless the B- and P- markings are not clear on your X3’s BMS (it happens sometimes), just do as said above : connect B- to P- by a wire.
If not sure, publish your picture with a drawing of the wire and ask confirmation before soldering. The mod is much easier than you think !