Just now seeing this. I have a handful of G5s sitting in amplified chargers and active 24/7 (in the house). Periodically, the charger cradle's indicator light will (inappropriately) change from "fully charged" to "charging." If I don't catch this quickly, the system seems to continue with unregulated / non-stop charging...resulting in significant battery heating/swelling. Thus far, no ruptures or explosions. If I catch this charge indicator light change quickly, I can pull the radio out and do a hard reset (battery pull) before battery damage ensues -- and I also pull the booster unit's power cord. I've found that the only reliable sequence for restablishing proper charging is to: Pull the battery and re-insert it 30 sec later (simultaneously yanking and re-inserting the booster device's power cord, although unclear if this truly is impactful) , Power on the device and let it boot up, Power down the device, Place the device onto the cradle, Power back up the device. If I simply hard-reset the device and place it back onto the cradle, the charging trouble seems to not go away.
I've noted that AC power flickers seem to trigger this problem. For example, power was lost at my house for 2 minutes a few weeks back - and this caused the aforementioned issue for 3 device-charger combos. I got to them quickly and all was fine. At other times, while away from home, brief known power outages have occurred and by the time I got home, several batteries were already swollen. There have been a few scenarios in which I've gotten home from work and found this issue - but there was no indication (from home appliance clocks, etc) of any power failures having occurred.
In total, I've replaced 6 total batteries across 4 devices, in 6 months. A fifth device has never suffered such a failure.
Clearly, brief AC power loss seems to trigger some sort of charging dysregulation. It is not clear to me if the charger booster device circuits plays a role in this. I've contemplated setting up uninterrupted /highly regulated power supplies (with battery backup) - as used for computers - for each of the Unication combos ....but that sure would be costly & cumbersome.