Epson ActionNote 866C User Manual page 62

Note
You can also purchase an optional external battery charger
so you can charge an extra battery while using another in
your computer.
To charge the battery, leave it in the computer. Then connect
the AC adapter. The computer automatically charges the
battery whenever the AC adapter is attached.
It takes approximately 1.5 hours to charge a completely
discharged battery when the computer is off or when it is in
Suspend mode. If you use the system while the battery is
recharging, it can take up to 2.5 hours.
If you find that over time the battery is losing its charge sooner,
the life of the battery may be reaching its end. Try letting the
battery discharge completely; then recharge it. If this fails,
replace it with a new battery.
Note
NiMH batteries are recyclable. When you need to discard
your battery, contact your local government agency for
recycling information.
Powering the Computer 3-5