How many hours should the battery of a new mobile phone be continuously charged after it is used up?

At present, all Samsung mobile phones on the market use lithium batteries, which have been activated before leaving the factory, so it doesn't take too long for the new mobile phone to charge for the first time. It is recommended that you connect the original charger when the mobile phone prompts that the battery is low, and then charge it after the prompt is full 1-2 hours. It is recommended not to use a mobile phone/tablet when charging, but to stand by while charging.