not sure how this is true but maybe I will test it with the new phone...
taken from the different post "Charging to 100% is your reason why battery is dying so fast. Max charging to 80% is ideal. Ios 13 will have a feature when it will keep the battery at 80% until the phone determines, based on your charging pattern, to charge to 100% just prior to you being active on the phone. If you keep battery between 40-80%, you will extend life significantly. My X after two years is still at 94% and I'm a heavy user. Don't let it drop below 20% either, both extremes are very bad for lithium batteries."
What do you think?