Therefore, when charging a mobile phone, no matter what power strip or charger it is, it is best to plug in the power supply first, so that no pulse voltage is generated, which is relatively safer.
If you're using a lithium-ion battery for the first time, it's important to fully charge it before use. This will help ensure that the battery performs optimally and lasts as long as possible. Here's what you need to know about charging a lithium-ion battery for the first time.
How to charge a lithium ion battery?
Here are some tips for charging your lithium-ion battery: Make sure you are using a charger specifically designed for lithium-ion batteries. Using the wrong type of charger can damage your battery or even cause it to catch fire. Lithium-ion batteries should be charged between 32°F and 113°F (0°C and 45°C).
Here it may make a slight difference what order you plug them in. If you plug the power supply in first, it is going to be at (say) 9v, until you plug in the electronic device, and then its load will bring the supply down to somewhere around its rated 5v.
If you must follow a specific order, plug the charger into the AC power first, then plug the device to be charged into the charger. Why? Because I said so. That's about as good advice as you can get from anyone without specifying exact part numbers, and other specific information about the environment they are being used in.
What voltage should a power supply be plugged in first?
If you plug the power supply in first, it is going to be at (say) 9v, until you plug in the electronic device, and then its load will bring the supply down to somewhere around its rated 5v. Note in this case, you will always be starting at a higher voltage than the rated voltage since the power supply has already plateaued at the no-load voltage.
Good charging practices help the battery maintain optimal performance. Many believe that leaving a device plugged in will overcharge the battery and cause damage. However, lithium-ion batteries are designed with built-in mechanisms to prevent overcharging.