[Elephone P8000] Satbeginner:
P8000 Battery and charger tests

Hi all,

here my test results:

Charging of a mobile phone works like this:

A USB charger is just a 5V power supply, capable of supplying a certain maximum current.

The current drawn from the charger however is controlled by the phone itself.

Inside the phone is a charging circuit that decides how much current it will allow into the battery.

Also this charging circuitry can 'see' whether it is connected to a AC wall-charger ,capable of supplying a higher current, or a PC-usb port, only capable of supplying 0.5Amp.

This can be seen on the phone in 'Settings' under 'Battery', it will say something like "charging" in case of a USB-port, or "AC-Charging" when using a wall-adapter.

To be able to do this, mobile phones use the USB data signals coming from the PC-port or AC-charger. However, not all Chinese phones do this the same way (most do!), but Apple uses a different configuration of the USB data signals.

I did some tests with both the battery and charger of the P8000.

Although the P8000 charger is sold as a 2Amp charger, I found it has difficulties delivering 2Amp. At a 2Amp load the voltage drops and it is getting quite warm.

I tested this by putting an external load to the P8000 charger, trying to draw first 1Amp, and secondly 2Amps from the charger.

At 1Amp it is OK, at 2Amps the voltage drops, and therefor also the 2Amp is not reached.

Is this a problem for our P8000??

No, I found the maximum current the P8000 draws from the charger during the charging cycle is 1.3Amp, and this is stepped down when the battery-level is reaching 80%.

Also when the battery is nearly empty a lower charge current is used by the phone.

In a earlier test I found the P8000 battery is around 4000 - 4100mAh, this is in line with the specs of the phone.

A full charge from completely empty to 100% will take about 3h30 minutes.

Since the phone controls the charging current in steps, there is no linear relation between charging-time and percentage full.

I also found that my white measuring tool does interfere with the USB signals, this lets the phone 'think' it is only connected to a PC-USB port, so it will use a lower charging current.

With this tool inserted in the circuit, the charging takes about 6,5-7 hours.

My small 'open circuit' tool does not have this issue, so with this tool the charging current steps up- and down during the charging cycle. With this tool inserted charging takes about 3H30 minutes.

So the claim Elephone makes about Fast-charging 10% in 10 minutes is more-or-less true, but only somewhere during the charging cycle.

If this were always true, a full charge to 100% would only take 100 minutes,this would be 1H40 minutes.

In real life, it will take a little over 3 hours to fully charge the battery.

So, overall charging does 5% in 10 minutes when coming from almost empty going to 100%.

In my humble opinion this is not a problem, because always charging batteries at the maximum current will deteriorate the lifespan of the battery quicker.

So I am quite happy with the battery life of the battery in this phone, and to be able to charge this battery in 3hours+ is really OK for me.

Here some pictures of the tools I used.

In the first picture you can see the voltage-drop when a 2Amp load is used.

The last picture shows my USB-tools.

Un saludo,

Satbeginner