It tells you to that you should charge the battery

• Turn the scooter's power switch to the OFF position.
• Connect the charger's plug to the charging port on the scooter.
• Plug the charger's power cable into a power outlet.
• When the charger's LED red/orange light is on, the battery is charging. Optimal charging time is 6 to 8 hours, or up to 10 hours to achieve a complete charge. The scooter manual will have the exact charging
• Times recommended for your scooter.
• Stop charging when the LED light is completely green.
• Disconnect charger from the scooter, then from the power outlet.
• Run your scooter before riding it to verify the battery charge.

I don't know what model of radio, but here is what I would try: pull the batteries and charge them on the charger by themselves if your charger allows this. The lights, well, some manufacturers just miss the boat. Especially on low end or "beginner" radios. I have one brand I can insert with NO BATTERY and the light comes on. Talk about useless. Charge times vary by size of battery and charger output, minimum is 3 hours, 12 hours much more likely but I see a lot at 5-7 hours. Hope this helps, model and brand helps always.

Depends on what battery. car battery I charge with i 10 means with a current 1 / 10 of the capacity in Ampere hours for 14 hours. So a 80 Ah battery with 8 A for 14 hours.
A camera battery in the charger I got with the camera. Or a good universal charger from GP. A NiMH AA or AAA battery, with a quick charger that at least needs 2 hours to charge. The quick chargers I have that can charge in less than 2 hours (one can manage in 15 minutes) all kill batteries after a few charge cycles. Hope this helps.

Sounds like it does not have enough battery power to stay on. If you have not tried to charge it, you should try that first. If you have, it sounds like it is not getting charged or not holding a charge. Could be bad AC power source, bad charger, bad charger connection or bad battery. Take steps to confirm that each of these are good. If all of these are good, sometimes the tablet can become so discharged that it will not allow itself to charge. When they are in that state, sometimes you can trick them into charging again by repeatedly disconnecting and reconnecting the charger as follows: With charger plugged in to AC power source, connect the charger to the tablet. Pay attention to the screen or LED or whatever indicator your tablet has to let you know it is charging. You may see it momentarily indicate charging, or maybe not at all. Then unplug the charger from the tablet then immediately plug it back in and pay attention for the charge indication again. You may have to do this a bunch of times (like 20) until you see the indication that it is charging. When you do get the indication, stop unplugging and re-plugging and let the tablet charge for 24 hours (to a full charge). This trick doesn't always work. Sometimes the battery or charging circuit or an internal connection is bad and no amount of unplugging/re-plugging will fix a hardware problem.

not exact, to charge apropiate needs 10% more than nominal voltage. if not, will not charge the batteries.
And the charger its very important because you can over charge the battery.An example,if you have a 12 Amps Batteries each one if you put it in series will be 24 Volts.at parallel conection will be 12 volts but the double of Amps.
At serial connection will be 12 Volts the amps will be the same but the volts will be 24.

The charger at 12 Volts must be 13.8-14.5 DC Volts and divide the Amps in Hours.
The charger at 24 Volts must be 26-28 Volts. to charge well.

The charger for 12 amps batt example must charge 2 amps per hour at 6 hours = 12 Amps.(2 Amps Charger by 6 Hours Charging= 12 Amps.(Fully Charged.
3 Amperes Charger needs 4 Hours to charge 12 amps Batt.
5 Amperes Charger needs 2 Hours charging an a quarter
All of this is at DC Current.

Luck.

You should be OK to charge the battery for 10 hours at a constant current of about 90mA. I assume this battery is a 3.7v type, with a full charge voltage of about 4.2v (it would be useful to monitor this with a multimeter).
Some useful commentary is here: https://www.sparkfun.com/products/341
Good Luck

Borrow or buy a volt meter (DVM $10) and check the terminals ( + & - ) of battery contacts with charger plugged in radio & AC outlet.
Reading of 6.5vdc minimum, with batteries 6.0vdc. Charge minimum of 14hrs. Test op. No power, DVM each battery in radio while transmitting(pressing 'Talk') to ID witch or all batteries bad.

Absolutely. NiMH batteries are direct replacements for Nicads - in use and in charging.

Try this.

Plug your BB into the charger.

With it plugged in take the battery out.

Wait a minimum of two minutes then put the battery back in.

Let it charge for a minimum of an hour before touching any keys or the trackpad.

If it still won't charge consider replacing your battery.