There is no need to discharge a lithium-ion battery to 0% from time to time, contrary to the practice that prevailed with certain older generation batteries. It is even now not recommended: this type of battery degrades more quickly when it drops below 20% charge, a “danger zone” to be avoided as much as possible. The chemistry of a current smartphone battery perfectly supports frequent charges, it can be recharged often. However, it is not recommended to recharge it as soon as the opportunity arises, because its comfort zone is between 30% and 80% charge. It is also better to wait until the gauge of your smartphone drops to 25 or 30% before plugging it in.
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