Well, this wall charger is going to be a very interesting story. Wait! Why is the wall charger charging the phone without plugging it?! Well it’s a very simple answer. It has a portable battery inside the wall charger. This battery has a capacity of 5000mAh which maybe can charge a phone once. The 2-in-1 feature has the availability to charge phones from a AC Outlet or portably. The best thing is that the charger can recharge itself through the AC Outlet instead of charging from a wire. Lastly, the charger can fast charge from using batteries instead of connecting it to the AC charger.
You need the electrical plug for the AC Outlet which requires mechanical engineering. It also involves the designs of the battery which you need to do by engineering.
