My Android Battery Drops While Charging, not charge, discharges
Although, Android battery life has not been considerable but if your battery has developed any of these issues; your battery drops when charging, battery will not charge whenever you are using it on data or it discharges very fast, then you should read this post carefully. Below are few simple factors that cause any of these battery downtime.
Battery chargers are manufactured with specific current ratings and so do batteries. Turn off your phone, remove the cover and check your battery capacity. It might read 2600mAh, 4200mAh or 3000mAh. Now, check your charger, it reads 5V 2A or 5V 550mAh etc. You have just calculated the relationship between your battery and its charger. What would happen if I charge my battery with a 5V 2A battery charger when the battery's rating is 5V 2600mAh? This is common when your battery will not charge while using it either on data or other apps.
When your battery's rating is 2600mAh but you use a 2A charger to supply current to it, your battery will either add or drops during charging because your battery is needing extra 200mAh of current to support the 2A supplied by the charger. Your battery is now in a practical floating situation "Do I pull back or push forward?" This is almost the same thing with charging your battery on a low voltage source. Your battery is likely to either drop while charging or discharge so fast since the current it gained was not sufficient.
Akin to that, What would happen if I charge my battery with a 5V 3A battery charger when the battery's rating is 5V 1600mAh? There has been arguments that your battery might blow off when used on excessive input current. But on a common nature of it, your battery requires a maximum amount of current, 1600mAh but it is being given much than it requires. What do you think will happen when you placed a 40kg load on a 30kg child? It could damage the battery. Batteries have charge rate ratings, and exceeding them regularly will cause faster decay of the battery. With this, battery will not charge.
I have two different charging equipment (Black USB head and white USB cable). The head charger has a USB port for external USB cables. I bought this separate chargers because i had few money to spend buying charger. My battery was slow on charging because sometimes it drops while charging. When i switched off the phone, it was faster. Now, the magic was how fast a 100% discharges in few hours. Although my battery is perfect. Be careful with cheap and fast chargers like that of my story. They are bad for battery life when they work due to their different circuitry combinations - from different manufactures
Some energy savers restricts energy during charging. I would not condemn energy savers or battery doctors. At least, they are good. Some of these energy savers use fast charge to speed up charging time on smartphones. Some MTk phones do not support fast charge. In my earlier times with MTk, i had issues charging my phone to 100% but later resolved it by just installing my battery saver. If you are using the compatible charger but yet your battery drops while charging or won't charge even when plugged while using it, then you should uninstall any battery saver. If no battery saver is installed, then consider battery replacement.
Conclusion: Always make sure that your battery is okay before taking the above resolutions. DO NOT opt to buy cheap chargers instead study charger and note their current capacities. Stick to your manufacturer's recommendation for your device.