How should I charge my phone ( avoid fast charging)?

Question

I've recently got a new Samsung Galaxy A5 (2016) running Android 6. It's great, but I'm not sure how to charge it properly.

By using the charger that came with the phone I get a notification saying "Fast Charging" and the phone heats up like crazy so it can shorten the life of the battery (although it does actually charge really quickly).

Alternatively I can use 3rd party chargers (none of which obviously suport fast charging), but many websites say it can harm the battery because they can be of really bad quality, so I don't like that option.

The best option I see is to charge it using my PC, but I can't have my PC everywhere I go and leaving it on overnight seems like an energy waste (no, my PC can't charge when it's off).

Disabling Fast Charging seems like a good idea, but since the Marshmalow update, the option is not in the settings anymore.

The text on the stock charger says:

Input: 100-240V 50-60 Hz 0.50 A

Output: 9V DC 1.67A or 5V DC 2.0A

With all that in mind, what is the best way to charge my phone and do minimal damage to the battery in the long run?

— Ciprum | Sources

Answer

You have multiple options :

Power bank that doesn't support fast charging

Normal 5 V 2.0 A or 5 V 1.0 A charger ( since fast chargers are backwards compatible )

Using a USB hub between charging port and device

Using a custom kernel that can lower charging current ( if device is rooted)

Using a Power only ( no data ) cable

As confirmed by OP, the last option worked and they wanted to know Is it safe?. To answer that, we need to understand how such cables are designed

A Power only ( no data ) cable uses Pins 1 and 4 ( refer USB layout )

Which means pins D + and D - are NOT used. These pins are responsible for negotiating the power requirements - (see Overview of USB Charging for more details )

Li Ion batteries charge in stages ( see Figure 1 ), which means that different voltage and current levels are required at each stage. Stage 1 corresponds to < 20% and Stage 3 > 70-80 â„… ( roughly - from experience )

Since D+ and D- pins are not used to negotiate the power required for each stage, such a cable will provide a constant Voltage or Current at all stages, which is not desirable

From a theoretical point of view it should be OK, if you are charging from 20 to 70-80% , but this may not be practically feasible. So, it is safe , IF, you ensure this charging limits

From a purist point of view ( as your question indicates), it is safer for battery to use the option of using a normal charger (that negotiates requirements, while charging ) and that is the best way ! You can buy older OEM chargers that charge at 2A

— beeshyams | Sources

How should I charge my phone ( avoid fast charging)?

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