This is the latest offering of the Xiaomi portable charger line, very similar to the previous “Xiaomi Power Bank Pro” model which also has a 10,000mAh battery. Key differences are the micro-USB instead of the USB-C port and the price. I’m a big fan of Xiaomi portable chargers (like GOAL ZERO YETI 150 ) and I immediately pre-ordered mine when it appeared on BG. This is not a free-item review as I paid full price for it
Specs from Xiaomi:
Material: Aluminium Alloy
Capacity: 10,000mAh 3.85V ( 38.5Wh )
Product weight: 0.250 kg
Dimensions: 130 * 71 * 14.1mm
Battery Type: Lithium polymer battery
Input: 5.0V2.0A, 9V/12V18W
Output: 5.1V2.4A 9V/12V15W MAX
One of the reasons I love Xiaomi power banks is because they state all the numbers in the spec, including the energy rating which is useful to measure efficiency. This version uses a 3.85V battery which gives it a slight advantage in energy as compared to 3.6V and 3.7V chemistry. Higher nominal voltage and an extremely efficient conversion module gives the Xiaomi 2 the almost unbelievable results in the discharge tests (See below).
It comes with a short USB cable and a brief instruction manual in Chinese (not pictured)
Build quality and interface:
The Xiaomi Power Bank 2 is very sleek and can easily be confused with a 5,000mAh power bank. Being made from an aluminium casing, build quality is great and it feels very solid.
Close up of the finish and CNC machined logo. Very even anodizing in a dark blue-grey tone.
Operation and performance:
-It has auto start when a device is connected
-Will automatically turn off after 30 seconds if a load is not detected
-One single button operates the power bank, it will turn on the output or restart it when pressed.
-Double click activates a low current mode, designed to charge/power low power devices such as bluetooth headset, USB lamp, keychain flashlights, etc. These devices draws very small of current and in normal mode would not keep the power on.
-Pass-through charge is possible but QC is disabled for both input and output.
“Real world” device compatibility test:
When doing tests on a power bank it is much different to use a USB load than a real device. Most of the times a dummy load will force the power bank to put out certain power while in a real world situation it will not do the same with a phone or other devices. My devices for this test each have certain characteristics when it comes to drawing power:
-iPhone 7: Charges up to at 2A, but limited to 1A if the coding is not correct.
-YZXstudio 8th Gen powerbank: will automatically detect the output and switch to highest possible charging voltage (12V).
-Aukey 30,000mAh powerbank: one of the few devices to draw 2.4A, some chargers don’t provide Apple 2.4A coding or can’t handle this current and will trip.
-iPhone7: Charged fine at 5.2V/2A
-YZXstudio powerbank: Maximum charge rate detected was 12V/1.2A. The YZXpowerbank will draw as much current as possible until the voltage drops 0.5V. This is inline with the specs, 15W @ 12V Max.
-Aukey powerbank: Charged fine at 5.1V/2.4A
The included USB cable is the flat type and measured 0.09 Ohm resistance at 5V 2A. This is good compared to my other short cables.
-Maximum input using a QC3.0 adapter was 9V/2A
-From empty to full it only took 3hr 38min, impressively fast.
-49.6Wh required to fully charge with an efficiency of 77%
-After being fully charged it draws 33mA while idle
-There is a current dip to 0 every ~10 minutes during the CC phase, this only lasts a couple seconds but it is enough for the graph to pick it up. I think this is how it tells the battery voltage without applying a charge. The dip is sightly visible in the voltage line because the Anker PowerPort+1 has voltage compensation when under load (lower current = lower voltage, as you can see towards the end of the charge). I will have to test it again with another charger and see if this happens as well.
This is my new style of graph for my power bank reviews, now includes the energy axis. That is a nice and sharp CC/CV drop.
5V/1A: output was completely flat, putting out 36.84Wh in 6:57 and achieved an amazing 95.6% efficiency. This is one of the highest of any power bank I’ve ever seen, a very close match to the YZXstudio 8th which is several times more expensive.
-Spec shows 6,900mAh of output capacity at 5V/1A rate and I got 6,959mAh. Not something you see everyday!
-The internal battery is LiPo with a nominal voltage of 3.85V, so compared to a 3.7V 18650 power bank of the same capacity there is a small energy increase.
-Compared to the older Xiaomi 10,000mAh (pictured above), I’m getting roughly 7Wh more at 5V/1A which is a dramatic 23% increase. This is enough to give an extra full charge to a smartphone with a ~1300mAh battery.
I’m overall very impressed with the performance of this power bank, given its compact size and price I would say this is simply the best 10,000mAh power bank you can buy.
-Slim, lightweight and great build quality.
-Extremely high efficiency, out-performs most higher capacity and more expensive power banks.
-Strong output enough to charge the most power hungry devices. Recharges very quickly as well.
-None! For the price I have no complains.