- Source: [Smartphone fast charging technology – myths and facts - SlashGear](https://www.slashgear.com/smartphone-fast-charging-technology-myths-and-facts-05627664/) - The battery charging technology being used is based on Programmable Power Supply (PPS) and USB Power Delivery (USB-PD) 3.0 standards. Delivers enough voltage and current to avoid battery degredation. - Samsung, OnePlus, and Apple have set fast charging standard at 30W, but some Android phone makers have 55W or 65W chargers. - Doesn't damage the battery over time - Lithium-ion batteries do not need to nor should you drain the battery to zero and then recharge to full capacity. This should be avoided. - When charged with a fast charger, a battery starts to get stressed at 80% full. For this reason most fast charges have a voltage control mechanism that start to trickle charge when 80% is reached. - The rule of thumb is to re-charge when the phone reaches 20-30% and charge it to 80-90%. This is the sweet spot to extend the life of the battery. - Heat is the real problem, so charging up to 80-90% keeps the heat down. - Recommended tricks: don't run the display and put the phone in airplane mode while charging. If possible remove the phone from a case while charging, again to keep the heat down.