There is a caveat - WARNING:
ANY batteries you have in the radio will always be in charge mode when using an external power source and the radio is off. So that means if you have alkalines in use, it's going to try and charge them.
The charging current has been previously documented at 30mA.
This is very small. So small in fact, that I do not believe it is even capable of being able to fully recharge Yaseu's 500mAh or 700mah battery pack, let alone todays high capacity batteries.
You are better off using an external charger. The batteries I use are rated at 2900mAh, and I never use anything less than 700mA when charging.
No pictures to show the mod so I'll get long winded on how to do it
Take a piece of aluminum foil, and fold it over unto itself two times.
Make it very flat.
Make it so it's about the same width as a toothpick.
Remove the batteries from the radio.
You will notice on the bottom of the battery compartment, there is a flat metal tension spring that is used to make contact with the Yaseu rechargeable battery pack. Take the piece of foil you made, and slide it just under that spring. (If you made the foil just the right size, it will also be touching the spring on it's width side also.) Make it reach all the way to the negative battery spring on the side of the case. This is the tough part, to get it just right. Try to wedge that side of the foil near the back of the spring, near the very bottom of the spring, to hold it tight. Don't force it too hard or you may break the spring from its mount. The trick is to make that piece of foil just right, so it stays wedged both behind the bottom recharging spring and the battery recharging spring, it is laying very flat, and once it is fully installed, it is not protruding out of the bottom spring on the other side, where you first started inserting the foil.
This works great here.
At the very least it keeps me from removing and fully recharging the batteries somewhat, without having to re-open the battery compartment all the time.