Zte A139+ User Manual page 19

The battery can be recharged for hundreds of times, but it will eventually wear out.
When the operating time (talk time and standby time) is noticeably shorter than
normal, it is time to replace a new one.
Please stop using the charger and battery when they are damaged or show
evidence of aging.
Return the wear-out battery to the provider or dispose of it in accordance with
environment regulations. Do not dispose of it in household rubbish.
Only use the original batteries. Using any unauthorized battery may affect your
handset performance or may cause danger of explosion, etc.
Warning: If the battery is damaged, do not discharge it. If the leakage does come into
contact with the eyes or skin, wash thoroughly in clean water and consult a doctor.
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