NGM dynamic now Quick Manual page 36

Inserting the battery
Your device is provided with a lithium-ion battery and is designed to be used exclusively
with original NGM batteries and chargers. The battery must be inserted into the backside
of the phone. Insert the battery into the battery compartment with the contacts facing up,
matching those of the phone. When done, put the hind cover back into position as shown
in the following illustrations.
36 ENGLISH