Thrunite C2 power bank and charger

DSC_7293

A single LiIon cell power bank and charger with fairly high power.
Official specifications:



How does it look

DSC_7289

The power bank is delivered in a brown cardboard box.

DSC_7290

It contains the power bank, a usb cable, a bag, a thank you note and a instruction sheet.

DSC_7296

In the power bank was a Trunite 3400mAh battery.

DSC_7291

The bag.

DSC_7294

All connectors and one indicator is placed at one end
DSC_7295 DSC_7297

The tail unscrew making it possible to replace the battery or just use it for a 18650 charger.

DSC_7298

It has springs at both ends.

DSC_7299



Measurements

Most testing is done with a unprotected Sanyo 18650GA cell.

Thrunite%20C2%20load%20sweep

It may be rated for a maximum output of 3A, but it do not have an overload protection (A protected battery would add that) and the voltage is starting to drop before 3A.

Thrunite%20C2%20charge%20load%20sweep

With charge current connected it looks like the output current is taken from the input.

Thrunite%20C2%20usb%20out%2010%20ohm%20%28SA18650-33%29

The current version has a problem keeping the output on at low current, i.e. I could not do the 10 ohm trace.

Thrunite%20C2%20usb%20out%205%20ohm%20%28SA18650-33%29

At 1A there is no problem and it can run for about two hours.

Thrunite%20C2%20usb%20out%205%20ohm%20%28Thrunite%29

The Thrunite cell has slightly less capacity.

Thrunite%20C2%20usb%20out%202%20ohm%20%28SA18650-33%29

At 2.5A it has trouble keeping the voltage high, when the battery voltage drops.

Thrunite%20C2%20usb%20out%202%20ohm%20%28Thrunite%29

Using the protected Thrunite battery is even worse.

10ohm

The noise is low at 0.5A load with 13mV rms and 100mVpp.

5ohm

The noise stays low at 1A with 15mV rms and 115mVpp

2ohm

At 2.5A the noise is also low with 17mV rms and 117mVpp.

Thrunite%20C2%20charge%20%28SA18650-33%29

The charge current is a bit high at 2.2A, but it makes it fairly fast to charge the power bank. The high termination current do also help making it fast, but means the battery will lack a few percent in being full.

Thrunite%20C2%20charge%200.5ohm%20%28SA18650-33%29

Adding a resistor in series with the 5V power supply to simulate a long cable or weak supply, will slow down the charge.



Conclusion

The power bank turns off at way to high load, making it difficult to use for many things, as a charger the current is on the high side (Using a 18650 that is rated for high charge current would fix that). I am not impressed with the rated 3A output, I would have prefered a 2.5A with overload protection.
The construction is nice with a aluminium tube and easy replaceable cell.

For now I cannot really recommend it, making it better at staying on would fix some of it.



Notes

The power bank was supplied by Thrunite for a review.

Read more about how I test USB power supplies and chargers