Batteries chemically wear down as a result of repeated charging and discharging throughout ordinary usage, losing both energy capacity and output power, which results in loss of processing speeds followed by system outages. Battery capacity may be reduced to 80% after few hundred recharges, and the drop in performance accelerates with time. Some mobile phones are designed with batteries that can be interchanged upon expiration by the end user, usually by opening the back cover. While such a design had initially been used in most mobile phones, including those with touch screen that were not Apple iPhones, it has largely been usurped throughout the 2010s by permanently built-in, non-replaceable batteries; a design practice criticized for planned obsolescence.
batteries chemically wear down as a result of repeated charging and discharging throughout ordinary usage losing both energy capacity and output power which results in loss of processing speeds followed by system outages battery capacity may be reduced to 80% after few hundred recharges and the drop in performance accelerates with time some mobile phones are designed with batteries that can be interchanged upon expiration by the end user usually by opening the back cover while such a design had initially been used in most mobile phones including those with touch screen that were not apple iphones it has largely been usurped throughout the 2010s by permanently built-in non-replaceable batteries; a design practice criticized for planned obsolescence