Nokia Lumia 920 Manual page 39

To unplug a charger or an accessory, hold and pull the
plug, not the cord.
When your charger is not in use, unplug it. Do not leave a
fully charged battery connected to a charger, as
overcharging may shorten the battery's lifetime. If left
unused, a fully charged battery will lose its charge over
time.
Always keep the battery between 15°C and 25°C (59°F and
77°F). Extreme temperatures reduce the capacity and
lifetime of the battery. A device with a hot or cold battery
may not work temporarily.
Do not dispose of batteries in a fire as they may explode.
Obey local regulations. Recycle when possible. Do not
dispose as household garbage.
Do not dismantle, cut, crush, bend, puncture, or otherwise
damage the battery in any way. If a battery leaks, do not
let liquid touch skin or eyes. If this happens, immediately
flush the affected areas with water, or seek medical help.
Do not modify, attempt to insert foreign objects into the
battery, or immerse or expose it to water or other liquids.
Batteries may explode if damaged.
Use the battery and charger for their intended purposes
only. Improper use, or use of unapproved or incompatible
batteries or chargers may present a risk of fire, explosion,
or other hazard, and may invalidate any approval or
warranty. If you believe the battery or charger is damaged,
take it to a service center before continuing to use it.
Never use a damaged battery or charger. Only use the
charger indoors.
Additional safety information
Read the additional safety information about your
product.
Make an emergency call
1. Make sure the phone is switched on.
2. Check for adequate signal strength.
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