I've got one that looks like it's fairly new in my battery rotation (probably sitting around unused for awhile) that seems to have failed. It reads a full charge, 4.2volts, but put into two different Vamo's, generated a flashing 02. Curious on what the issue might be.
They are the only two APVs that use that size battery. I read the voltage off a multimeter and I'd guess that the battery could be six months old or so. I have a flashlight on order that uses that size battery so I may be able to see if it's something in the Vamo circuitry that has decided it doesn't like the TW battery, I just thought someone may have experienced the same issues.