Xiaomi power banks (Xiaomi) - the most complete rating of devices. Xiaomi power banks (Xiaomi) - the most complete rating of devices More efficient charging and operation compared to the previous generation

Xiaomi Mi Power Bank 2i New – updated Xiaomi external battery 10000 mAhwith support for fast charging and two USB ports. It is suitable for any electronic devices and gadgets - phones, smartphones, cameras, flashlights, etc.

Compact body

The case of the Xiaomi external battery is made of anodized aluminum alloy, which makes it as durable as possible and protected from various types of damage. In addition, it has anti-corrosion properties and is protected from condensation.

The surface of the body of Xiaomi Mi Power Bank 2i (PLM09ZM) is sandblasted, so it is pleasant to the touch and does not slip in your hands.

The size of the Xiaomi Power Bank 2i is 71.2x147x14.2 mm, due to its compactness, it is convenient to carry in your pocket or purse, and also to take with you on trips.

Power Bank with fast charging

The basis of the Xiaomi PLM09ZM battery is a lithium-polymer battery. This allows it to be used in a wide temperature range, while it has a low self-discharge percentage.

Xiaomi Mi Power Bank 2i 10000 mAh supports the Quick Charge 2.0 fast charging function - after connecting the gadget, it determines the optimal voltage and current: 5 V - 2.4 A, 9 V - 2 A or 12 V - 1.5 A. Charging can be done in 2 standard USB type A ports.

The charge level of the Xiaomi external battery is shown by 4 LED indicators on the case in 25% increments.

In addition, the Xiaomi power bank itself can be charged using QC 2.0 fast charging with a voltage of 5 or 9 V and a current of 2 A in 4-5 hours.

In the VOLTA online store you can buy an external battery Xiaomi Mi Power Bank 2i New 10000 mAh (PLM09ZM) with delivery to your city.

Show full description

Equipment Xiaomi Mi Power Bank 2i 10000 mAh (PLM09ZM) silver

  • external battery Xiaomi Mi Power Bank 2i 10000 mAh (PLM09ZM)
  • microUSB cable

55 million sold Improved Technologies 14.1mm thick
A day full of energy! Beautiful and comfortable Compact body
Just as a full breakfast allows us to start a new energetic day, the Xiaomi Mi Power Bank 2 external battery will help charge your smartphone with energy. The same 10,000 mAh, but the charging speed has noticeably increased. Along with the classic silver color, Xiaomi has also released a more practical dark version. From the commute to work to long trips, the Xiaomi Mi Bank 2 external battery can become your constant companion. Anodized aluminum alloy body + 180° rounded edges The one-piece metal body made using anodizing technology not only has a stronger structure, but also is more wear-resistant; In addition, it also has anti-corrosion and anti-fog properties. Sandblasting and rounded edges of the case make it more ergonomic and pleasant to the touch than the first generation Xiaomi Power Bank. The width of the Mi Power Bank 2 external battery is only 14.1 mm, and has decreased by 1/3 compared to the previous generation, due to which the device can easily fit into a pocket or bag.


Fast charging and increased operating efficiency

The smartphone will charge quickly

The power bank automatically recognizes the connected device and applies fast charging technology. To charge the improved version of Xiaomi Note, it will take only 1 hour 55 minutes, which is 20% less than the previous generation. You can also charge the device itself using the 5.0V-2.0A,9V / 12V-18W input, thus significantly reducing charging time.

It doesn't matter day or night

Increased charger capacity

When you go to bed, it still continues to work. The actual battery capacity of the Xiaomi standalone charger 2 is 6900 mAh, which is 10% more than the previous generation. A reliable and stable charger will increase the operating time of your smartphone, tablet or digital camera. Despite the fact that the amount of electricity remains unchanged, you can now charge more gadgets. The actual energy capacity of the battery is 6900 mAh. The charging conversion rate for various devices reaches 93%

High Density Lithium Polymer Battery

More efficient charging and operation compared to previous generation

The Xiaomi mi Power bank 2 uses an original lithium polymer battery from ATL. The advanced chipset not only makes the charger safer, but also, complemented by high-precision RC sensors, significantly improves efficiency and stability.



Easily adapts to charging devices

Supports charging at minimum current

By double-tapping the power button, you can turn on a two-hour charging mode at a minimum current, with which you can charge wireless Bluetooth headphones or a Xiaomi bracelet. You no longer have to worry about how to charge small gadgets with minimal current.

High quality chip

Short circuit protection

In manufacturing, electrical battery charging/discharging microcircuits from Texas Instruments and Zimi are used, which not only provide nine types of short circuit protection, but also generally significantly increase the performance of the charger.

Thermal control mechanisms have been added to ensure a safe temperature for battery operation. Added safety elements that are automatically triggered when a short circuit occurs, thereby preventing damage to the motherboard and battery. Reset circuit protection has been added, which in emergency circumstances allows you to restore the operating state of the autonomous charger by pressing the power button.
Added OVP circuit protection to prevent incoming voltage from being too high causing damage to the device. If the MicroUSB connector is used incorrectly (inserting the plug backwards), the electrical circuit is automatically turned off to protect the device. The autonomous charger “intelligently” checks the power of the output current, and, if it exceeds the limits, automatically turns off the current output, thus protecting the device from damage.
The charger promptly checks the voltage level and, if it exceeds the limits, automatically turns off the current output, thus protecting the device from damage. A special Japanese protective device for lithium batteries has been added, which will effectively protect the battery charger from unnecessary overcharging and overdischarging, thereby maintaining its durability. At the hardware level, the device is checked for current power and the presence of short circuits. When a problem is detected, the protection operates instantly, breaking the contact thread and ensuring the safety of using the battery.


*Statistics shown above are the result of testing by Zimi. If the objective testing environment changes, the results may differ. The picture shows the charging process of Xiaomi 5; for normal operation of the charger, you will need to connect the Micro USB plug to the Type-C adapter.

Notes

1. When charging the device, the indicators flash alternately. After finishing, they all burn together without blinking
2. Low current mode is turned on by double pressing the button and turns off after an hour. Forced shutdown can be done by pressing the button once
3. The device turns off automatically, the button does not respond to turning off

Xiaomi's history of portable batteries began with the Mi Power Bank 10000 mAh, which is still the world's most popular portable battery for charging electronics. Over the past two years, the Chinese corporation has managed to release a large number of other portable batteries, but it is the version with 10,000 mAh capacity that is the most optimal, according to many.

At the beginning of 2017, Xiaomi presented and began selling the Mi Power Bank 2 10,000 mAh battery, which differs from its predecessor in a thinner body, new hardware and, of course, a higher maximum current strength - 2.4A versus 2.1A in the first generation.

You can buy Xiaomi Mi Power Bank 2 10000 mAh in two colors – Silver and Black. In our case, the choice fell on black, as it looks more “fresh” and interesting. Otherwise, except for the difference in color, the two versions of the second generation portable battery are no different from each other.

The Mi Power Bank 2 10000 mAh comes in a stylish white package with an image of the device itself on the front. Since most Xiaomi products are intended for sale in China, there are inscriptions in Chinese on all sides of the box. I would like to believe that in the near future the company will finally begin to carry out all designations in English, which will allow it to more actively promote its products on the international market.

In the package you can find another one, inside which there is a small manual in Chinese, a microUSB - USB cable, as well as a black portable battery itself.

The length of the microUSB cable is 30 cm, whereas in the first generation it was 20 cm. Most likely, Xiaomi employees realized that buyers of portable batteries experience inconvenience due to too short charging cables, so the Xiaomi Mi Power Bank Pro with a USB connector Type-C cable length has increased to 30 cm.

Of course, the greatest interest is the Mi Power Bank 2 10000 mAh itself. The black color in real life beautifully and gracefully shimmers into purple and dark blue colors. In general, the black color turned out to be very unusual, but extremely on-brand. In just a few minutes, a large number of greasy hand stains appeared on the body. In bright light they are clearly visible.

The build quality of the second generation portable battery is at a very high level. There are no cracks or distortions anywhere, and the aluminum body has a fairly large margin of safety, so it will not be so easy to damage it. However, the black color of the Mi Power Bank 2 will show scratches and abrasions over time. The solution to the problem may be to purchase a silver model or a protective case.

The dimensions of the Mi Power Bank 2 10000 mAh case are 71 x 130 x 14 mm and weighs 217 grams. For comparison, a model with a similar capacity has dimensions of 75 x 128 x 13 mm and a weight of 218 grams.

The Xiaomi Mi Power Bank 2 10000mAh Portable Battery has short circuit protection, overheat protection, and overload protection. Like all other Xiaomi batteries, there is an LED indicator on the side of the device that tells you the remaining battery charge. Next to it is a glossy plastic button that allows you to switch and independently adjust the current in cases where it is necessary.

The Mi Power Bank 2 10000 mAh battery supports fast charging technology with a power of 9A at a current of 2A. Thanks to this, when using the appropriate power adapter, the time to fully charge the portable battery is 3 hours 30 minutes - we tested.

As for the efficiency factor (efficiency), Xiaomi claims 95% - this is a very good result. Thus, the real capacity of the Mi Power Bank 2 10000 mAh is 6900 mAh, which is enough for 2.4 charges of Xiaomi Mi5, 3.2 charges of iPhone 6s and 1.4 charges of iPad mini 4 tablet. All these numbers sound promising, but the editors website I decided to check the manufacturer’s words in practice.

A fully charged Xiaomi Mi Power Bank 2 10000 mAh managed to charge an iPhone SE (1624 mAh) as much as 2 times, and the third time only by 38%. If we talk about charging (5124 mAh), the portable battery was able to charge it completely once, and only 31% the second time. In other words, all the specifications declared by the manufacturer correspond to reality. After a couple of charge-discharge cycles, the capacity of Mi Power Bank 2 may “sway” slightly, so the results will be 5-10% better.

If we closely compare Xiaomi Mi Power Bank 2 10000 mAh and Mi Power Bank Pro 10000 mAh, then both of these portable batteries are only slightly different from each other. The first is equipped with a microUSB connector for charging, and the second uses USB Type-C. The dimensions of the cases are approximately at the same level, as well as the weight. These two batteries fully support Quick Charge 2.0 fast charging technology, which allows you to charge them in just 3.5 hours.

Xiaomi claims that the Mi Power Bank 2 can deliver a maximum current of 2.4A, while the Mi Power Bank Pro can only deliver 2.1A. Thus, if you add up all the pros and cons, the new portable battery is superior to its more expensive predecessor in all respects. If we were choosing between these two batteries, then the choice would definitely fall towards the Mi Power Bank 2 10000 mAh model, because, in addition to everything else, it is also almost half the price. We recommend for purchase!

Buy Xiaomi Mi Power Bank 2 10000 mAh at a very low price it is possible.

I welcome everyone who stopped by. The review will focus, as you probably already guessed, on the popular Xiaomi 10000mah PB and its non-standard application, namely the “mining” of high-capacity cans for flashlights and the sale of ownerless cans from a laptop. The review will include thorough testing, detailed disassembly, efficiency measurements, as well as detailed rework in the form of replacing batteries with cheaper/unnecessary ones. If you are interested, please see cat.

Part one. Description, testing and disassembly:

So, here is the “people's” PB Xiaomi 10000mah:

TTX:
- Manufacturer - Xaiomi
- Model – Mi Power Bank 10000mah
- Housing – silver anodized aluminum
- Battery charge indicator – 4 LEDs
- Real total battery capacity - 10000mah (3 banks of 3350mah each)
- Useful PB capacity – at discharge 1.75A (6090mah), at 1A (6420mah)
- Converter efficiency – 93% (I intended on average 90%)
- Input interface (charge) – 1 microUSB port (5V 2.0A)
- Output interface (return) – 1 USB port (5V 2.1A)
- Estimated current charging time (2A) – 5 hours (in 4 hours the PB is “compacted by 85-90%”)
- End of charge/discharge voltage of built-in banks – 4.195V/2.95V
- Simultaneous operation of charge/discharge modes – yes (independent channels)
- Built-in protection – yes (against overdischarge/overcharge/overvoltage and short circuit at input and output/overcurrent at output/overheating of electronics/incorrect connection)
- Power off button – no, the power bank is always in “sleep” mode (designed to reboot the power bank in case of problems)
- Dimensions – 91mm*60mm*22mm
- Weight - 208g

Why, exactly, did I buy this PB:
A few months ago, I noticed a comment from a comrade that the Xiaomi 10000mah PB contains not 4 typical 2.6Ah banks, but 3 high-capacity Sanyo NCR18650BF batteries, 3350mah each. After looking at the reviews, in particular the excellent review of the comrade, I was convinced that it really contains 3 good jars, and in retail the cost of one jar fluctuates around $5-6, i.e. When purchasing you need to pay at least $15. And if you take the PB, then it comes out to around $11. Moreover, in addition we get an excellent filling with an efficiency of about 93% and a stylish aluminum box, or simply an excellent capacious power supply with reduced dimensions. Agree, this PB is a very advantageous offer.

After comparing prices, it was decided to buy from the Gearbest store, because:
- judging by the reviews, reviews on thematic forums and the site itself, this is 100% original;
- taking into account the frequent price reduction to $12.3 (at the beginning of October for $10.99) and the use of points, it comes out to about $10. If anyone doesn’t know, for registering and uploading an avatar on GearBest you get 30 points, which is $0.6 (50 points = $1). In addition, relatively recently, there was a promotion where you could get 30 points (shown here in the “discounts” section) and in the end you can get it at a very “tasty” price, which is what I did.

A sore point for many - bought with my own money, taking into account promotional points it came out to $11 (at that time it was the cheapest price I found):


Vague doubts about quality:
The only thing that bothered me was the quality of the cans, because... Why should a company that has already established itself in the market work at a loss, because it is no longer a newcomer in this field, and the main law of marketing is to conquer the market - raise prices. Therefore, I was tormented by one question - “something is wrong,” and the PB 10400mah costs 18 tanks, and the 10000mah costs 12 tanks, but the latter also has better electronic components and is much cheaper. Either the batteries are of a low technological class, or stale, or... On the other hand, because of such a trifle as power supply, Xiaomi will not risk its reputation, and there seem to be no complaints from the reviews, but why such a price remains a mystery to me ...

Checking for originality:

We punch, enter the 20-digit code, which is located on the package under the protective layer:


If the PB is original, then something like this will pop up:


Well, attention to detail, in non-original PBs there is no “mi” symbol in the depth of the USB connector:


The logo is present, which, coupled with the code verification, means that the PB is 100% original.

The scope of delivery includes:
- box
- Xiaomi PB 10000mah
- charging cable, length 35cm
- instructions in Chinese

The box itself (it is slightly larger than the PB itself):




Everything fits perfectly inside (I removed the protective bag and sticker):


The front end panel is protected by a sticker; there is no sticker on the bottom, but there is some useful information on the parameters:


Hidden under the sticker are battery charge indicators, input/output ports and a reset button (2 indicators are lit, capacity from 25% to 50%):


Here's a comparison with the popular single-can cylindrical PB:


The dimensions are very small (91mm*60mm*22mm), perhaps this is the most compact PB at 10000mah. You can safely put it in your pocket, it won’t stick out much:


The weight of the PB is also small, only 208g, the case separately is 52g:


The kit contains the following instructions in Chinese:


And also a very high-quality flat cable in silicone insulation (very flexible), which can handle high currents without problems. The male USB plug contacts are gold-plated to reduce losses at high currents:


Well, a very useful function of simultaneous charging/discharging, i.e. By inserting, for example, a smartphone into this power supply unit for charging, and the power supply unit itself into the adapter/power supply unit, then in the end both devices will be fully charged, very convenient:

Distinctive features of PB:
- stylish, durable anodized aluminum body (does not rust, does not fade/turn yellow in the sun, has increased mechanical strength)
- ergonomic design (all controls are located on one side)
- reduced dimensions (21.4% more compact compared to the previous model),
- large capacity 10000mah with small dimensions
- high converter efficiency 93%
- high input/output current (2A/2.1A)
- simultaneous operation of charge/discharge modes (independent channels)
- compatible with most devices (automatically adapts the charging port to the type of connected cable)
- protection against overdischarge/overcharge/overvoltage and short circuit at input and output/overcurrent at output/overheating of electronic filling

What the manufacturer tells us:

Increased capacity and efficiency (by 30%) with reduced dimensions (by 21.4%):


Reliable internal protection. 9 protective layers of Kevlar manufactured by Texas Instruments:


A bunch of different protections (protection against overdischarge/overcharge/overvoltage and short circuit at input and output/overcurrent at output/overheating of electronics/wrong connection):


Minimum losses (efficiency 93%):


Various colors (but for some reason red and gold are more expensive):


Direct testing of the “flooded” capacity of the PB:

- Filled container– how much is poured into the battery, taking into account the converter (usually a little more than the actual capacity, since some energy is lost in the charging module/converter). Usually it is not of particular interest, but sometimes it is very helpful, for example, when charging a battery. It immediately becomes clear how much the battery is “packed”. Usually displayed on the screen in branded chargers. In our case, you can only look using a white tester.

Features of charging and measurements of the filled capacity:

First, let's see how much it was charged:


About 5400mAh was “filled” (8550mAh is filled into a fully discharged battery), therefore, the PB was charged by a third. But here’s what confused me, and really confused me - the charge current is only 1.33A, which is not good. After a complete discharge, I tried to charge this power bank again from a 4-port Orico DCH-4U charger and an Orico cable that easily passes 2A:


Alas, the miracle did not happen. I really hoped that in this PB the 2A current charge was normally implemented, so I had already finally decided that I would redo it. But why do some users claim that PB can take 2A? The Orico DCH-4U charger delivers 2A without any problems, the problem is clearly not there:


Let's try it with the supplied cable. It can be seen that it is worse than Orico, there is a slight drawdown and, as a result, a lower current, only 1.26A. It’s a long way from the stated 2A:


Having disassembled the guts, we see that without “charging doctors” a little more than 2A goes to the banks. In the photo, the ammeter (on the left) is connected between the “plus” of the board and the “plus” of the battery. Everything is fair, as the manufacturer claims and even a little more (2.2A):


But once you install the “charging doctor”, the current begins to be limited to around 1.3-1.4A:


The situation with the white doctor is similar:


There may be some restrictions, because... the manufacturer claims a “smart” controller that adapts to different types of devices. But at first I thought that either my copy was defective or the manufacturer was being disingenuous. It turns out that no, but still some users post photos where 1.6A is poured through a white tester.


Testing the “useful” capacity of the PB (of greatest interest):

We've sorted out the filled container, now let's look at the “useful” container, i.e. given after the converter.
- Useful capacity– how much we will actually get. It is calculated after the converter. The PB usually contains a boost/buck converter, which is far from 100% efficient, so by raising the voltage from 3.7-4.2V to 5V, it loses some energy (heating, inefficient components, etc.). Buck converters have the highest efficiency, but are more expensive. Therefore, if a manufacturer claims the capacity of their PB is 10Ah, this does not mean that we will receive them all. Approximate formula for calculating useful capacity:
useful capacity = real capacity * 3.6 / 5 * efficiency

PB discharge current 0.95A (the result is quite expected, 6420mah):


PB discharge current 1.75A (6090mah):


Let's summarize the output parameters:

Well, very good. The manufacturer claims an efficiency of 93%, let's see if this is true...

Disassembly of PB Xiaomi 10000mah:


All stages of disassembly in detail

This PB is quite easy to disassemble. To begin, use a thin watch screwdriver to remove the plastic covers from the ends of the device. They are held on with double-sided tape, so we tear them off little by little so as not to break them and spoil the stylish appearance (it’s better to pick them out from the inside of the ports first):




The other strip is picked out in the same way, do not remove the tape, it will still come in handy:


There are 4 screws at each end. First we unscrew the bottom, then we “glue” it to the end plate with a flat object and take it out (I stuck a flat screwdriver):


It turns out this picture:


Next, unscrew the other bar and push the entire frame outward from the negative terminals of the batteries:


It should look something like this:




The body is aluminum with stiffening ribs, and screws are screwed into them:


You can get the reset button, it is held on by latches:


To remove the board, you need to unscrew 2 more screws on the board and bend these latches:




That's it, the complete disassembly is complete:


Close-up of the board:


As you can see, there is a temperature sensor, although only one:


The board works well even without a case. During operation, it does not heat up much (the temperature on the side of the microUSB connector is 55°C with a discharge current of 1.75A, at the end of the discharge it rises to 70°C, since the currents in the converter are about 4A, but in a closed case there will be all 80° WITH):


Reassemble in the reverse order, remove the remnants of old double-sided tape from the plastic end caps with mild solvents, such as alcohol. Acetone dissolves black strips!!! See below for disconnecting the cans, soldering new ones and assembling the PB.


Stock batteries:

Inside there are 3 high-capacity Sanyo/Panasonic cans with a capacity of 3350mah each:


Having disconnected them, we get 3 good high-capacity cans; if necessary, we clean off the remains of spot welding in the contacts (sandpaper/knife helps):


Date of production of cans:
I already wrote about decoding some folk cans in my article about and testing, here is the same standard marking of panos.
Our banks have the following designations:
SANYO L
NCR18650BF 5422

NCR18650BF – model name
- the first digit is the year of manufacture: 1 – 2011, 2 – 2012, 3 – 2013, 4 – 2014, 5 – 2015, etc.
- the next digit is the month of issue: 1 – January, 2 – February, 9 – September…… X – October, Y – November, Z – December
- the third and fourth digits are the day of the month: 05, 14, 29.
Total: the production date of our Sanyo NCR18650BF 5422 cans is April 22, 2015, you see, they are quite recent.

Battery Specifications

Here is the datasheet for this battery model:


Here is a comparison of cans with their closest competitors in a comparator at a discharge current of 1A/2A/5A:






Discharge with typical current 2A to 3V:
Sanyo/Panasonic NCR18650BF 3350mah -> 2979mah (10,497Wh)
Sanyo/Panasonic NCR18650B 3400mah (basic of all varieties) -> 3104mah (10,821Wh)
Sanyo/Panasonic NCR18650BL 3350mah -> 2950mah (10,430Wh)
Lg INR18650MH1 3350mah (high current) -> 3014mah (10,685Wh)

Final table:


We run the banks on Opus BT-C3100 V2.2 with a current of 1A:


On average 3400mah per jar, not bad at all (one jar seemed to be constantly heated in the PB, even the adhesive tape got stuck, so only 3300mah). At the same time, the cost of one battery is around $4, plus excellent electronic components/housing. At retail, the average price of these cans is $5-6, and stale ones can arrive.


Converter efficiency measurements:

A few words about the coefficient of performance (efficiency). I don’t think there’s any need to explain what this is. For those who have forgotten, roughly speaking, this is an indicator of the effectiveness of the device. The manufacturer claims the efficiency of this device is around 93%. This means that 7% of the energy is lost in the converter/heat. Let's see if this is true. The calculations are not very accurate, because... The devices are not calibrated, but they display the general picture. For the readings of the white tester, an addition of +0.05V is made, which is extinguished in the “tail” of the tester. From the review - “The indicator slightly underestimates the displayed voltage (by 2%) and current (by 3%)”

The battery is fully charged, load discharge current is 0.95A (voltage about 5.1V):


We have:


- voltage at input/bank – 4.1V
- current at the input/banks – 1.3A
Power P1=5.1*0.95=4.85W
Power P2=4.1*1.3=5.33W
Efficiency = P1/ P2 = 0.91, that is, 91% with a return of 0.95A and charged banks, not bad.

The battery is fully charged, load discharge current is 1.7A (voltage about 5.05V):




- input/bank voltage – 4.06V
- current at the input/banks – 2.4A
Power P1=5.05*1.7=8.6W
Power P2=4.06*2.4=9.74W
Efficiency = P1/ P2 = 0.88, that is, 88% with a return of 1.7A and charged banks, not bad.

The battery is half charged, load discharge current is 0.95A (voltage about 5.1V):


- output/tester voltage – 5.1V
- output/tester current – ​​0.95A
- voltage at input/bank – 3.72V
- current at the input/banks – 1.42A
Power P1=5.1*0.95=4.85W
Power P2=3.72*1.42=5.3W
Efficiency = P1/ P2 = 0.91, that is, 91%, not bad.

The battery is half charged, the load is discharged with a current of 1.7A (voltage about 5.05V):


- output/tester voltage – 5.05V
- output/tester current – ​​1.7A
- input/bank voltage – 3.7V
- current at the input/banks – 2.7A
Power P1=5.05*1.7=8.6W
Power P2=3.7*2.7=10W
Efficiency = P1/ P2 = 0.86, that is, 86% with an output of 1.7A, decreased a little, but still excellent.

The battery is almost discharged, load discharge current is 0.95A (voltage about 5.1V):


- output/tester voltage – 5.1V
- output/tester current – ​​0.95A

- current at the input/banks – 1.77A
Power P1=5.1*0.95=4.85W
Power P2=3.08*1.77=5.45W
Efficiency = P1/ P2 = 0.89, that is, 89% with a return of 0.95A and discharged banks, not bad.

The battery is almost discharged, load discharge current is 1.7A (voltage about 5.02V):


- output/tester voltage – 5.02V
- output/tester current – ​​1.7A
- voltage at input/bank – 3.08V
- current at the input/banks – 3.43A
Power P1=5.02*1.7=8.53W
Power P2=3.08*3.43=10.56W
Efficiency = P1/ P2 = 0.81, that is, 81% with a return of 1.7A and discharged banks, more or less.

The efficiency of the converter is on average about 90%, but if you take into account inaccurate instrument readings and losses in the test leads, then the converter maintains the declared 93%. This applies to energy, but practically nothing to capacity.

Now for capacity:
Since the cans discharge up to 2.95V, and they give up their full capacity when discharged to 2.5V (see the “batteries” section), the result is about 9300mah (3100mah per can). Standard formula for calculating useful capacity:
Net Capacity = Real Capacity * 3.6 / 5 * Efficiency
We get - 9300*3.6/5*0.9=6030, we got a total of 6420mah at a discharge of 0.95A, and 6090mah at 1.7A.

Atypical uses of PB:
- “mining” cheap high-capacity Sanyo NCR18650BF 3350mah batteries at a low cost and using them in various devices (the market value of one can is $5-6);
- use the converter board in your DIY projects. It can simultaneously charge/discharge, has excellent performance characteristics and all kinds of protection, including against overheating, which is sometimes very important;
- good stylish aluminum case for various crafts;
- assembling your own “monster” into a large capacity (using Li-Pol batteries) or with other electronic filling;
- in addition to everything, an excellent stylish 2A cable of small size (high-quality cables of this length are difficult to find, branded cables come one meter each, but using them in a purse/bag is very inconvenient)

So, let's look at the advantages and disadvantages of this PB:

Pros:
+ brand, quality guarantee (this is not a name and not a “green” company, has been operating since 2010)
+ “honest” efficiency of the DC converter of 93% (minimum energy losses in the converter)
+ high output current of 2.1A (the voltage practically does not sags)
+ high charging current of 2A, and this reduces the charging time by 2 times compared to the typical current (some competitors still have 1A for 4 banks, and this is 0.25A for a 2.6Ah bank, quiet oooooooooo)
+ simultaneous operation of charge/discharge modes (independent channels)
+ stabilized output parameters (the output voltage does not “jump” as the PB discharges)
+ the presence of all kinds of protections (against overdischarge/overcharge/overvoltage and short circuit at the input and output/excess current at the output/overheating of the electronic filling/incorrect connection)
+ stylish appearance
+ the ability to disassemble without damaging the appearance (for example, Pineng PB and some others are tightly glued together)
+ reduced dimensions and weight with the same high capacity (almost all 10Ah PBs have 4 banks, including Xiaomi 10400, instead of 3 banks)
+ low price (analogs from other companies cost about $18-20)
+ high-quality complete cable (low drawdown under load, small size, just right for power supply)
+ availability of additional accessories (cases/bumpers, for example)
+ light weight and dimensions
+ steel case (a kind of mechanical protection, since many companies prefer cheap, poor plastic, which doesn’t look very good)

Cons (in general, these are not even disadvantages, but just whims):
- a primitive capacity indicator in the form of 4 LED indicators (I love devices with screens, everything is shown there clearly, for me this is a minus, for others it is not)
- one USB output port (the problem can be solved, but who carries and simultaneously uses two power-hungry devices)

Conclusion: if you are looking for a small, capacious power bank with excellent performance characteristics, this is definitely your choice. Coupled with the above advantages, I believe that this PB can rightfully be called “national”. I recommend to buy!

Part two. Replacing built-in batteries with less capacious/unnecessary ones

Reasons for modernization:

We needed high-capacity 4.2V cans for flashlights at a low cost
- I wanted to attach batteries from a laptop battery (5 good cans and 1 not so good 2Ah cans)
Once upon a time, my laptop battery died. Having disassembled it, I found 6 LG LR1865SE 2000mah cans, one of which died (it had an increased self-discharge, discharged to 2V after a couple of days of sitting in a discharged state). At first, I used them in the black 4-can PB AiLi169, which appeared in my first review of . But it had 5 huge disadvantages: large dimensions, heavy weight, high quiescent current (self-discharge), artisanal appearance and a charge current of only 0.5A, so it took 24 hours to charge it, and in the end the capacity was relatively small. Therefore, I almost never took it with me and collected it, which I often used. But the charge current there was also small, only 0.5A, and the “useful” capacity left much to be desired. At first, I wanted to attach three Sanyo 2.6Ah popular cans to this Xiaomi PB, but after thinking about it, I decided to abandon this idea, because... all the trump cards of the Sanyo 2.6Ah will not manifest themselves in any way (good discharge curve + frost resistance), but the popular Samson 2.6Ah were not at hand, so the choice fell on the 2Ah Skis from the laptop. It was decided to assemble my own PB by simply rearranging 3 more or less successful banks into Xiaomi. On my own behalf, I can add the following: if we put 2000mah banks instead of 3350mah, we will get 6000mah instead of 10000mah (9300mah, since the kit ones give up their entire capacity when discharged to 2.5V), and in terms of “pure” capacity we will get about 4190mah instead of 6420mah , which is more than enough for most consumers. Formula for calculating useful capacity = actual capacity * 3.6 / 5 * efficiency

Here are our players (I recommend installing the ultra-cheap Samsung ICR18650FM 2600mah). In my case, these are LG LR1865SE 2000mah batteries from a faulty laptop battery that were waiting in the wings in this AiLi169 PB:


First, let's check the battery capacity on the Opus BT-C3100 V2.2 analyzer:


Let's take 1, 2 and 4 jars, because Their capacities are almost the same. To be on the safe side, I recommend following the following algorithm:
- discharge original batteries (Sanyo NCR18650BF) in Xiaomi PB
- discharge the “donor” batteries (LG, Samsung) to the same minimum potential, it is more convenient to do this in some multi-bank PB
- first turn off “plus”, then “minus”
- connect new banks in the reverse order, i.e. first "minus" and then "plus"

So, here we go (direct modification):

Just in case, we isolate the positive terminals of the batteries with electrical tape, you never know:


Next, we bend the board and use a thin blade of a knife/clock screwdriver and carefully, without poking the tip into the board, pry out the positive current lead from the batteries ( There is no need to tear off the “plus” board, I just measured the efficiency):


It’s the same with negative ones, you don’t need to rip them off the board either:




We get something like this:




Since I don’t have spot welding, we will solder the current leads to the new cans. To do this, first align the current leads with pliers. The soldering algorithm is as follows: we drop a little flux (soldering/orthophosphoric acid) onto the contacts and tin (cover with tin/sold), the main thing is not to keep the soldering iron tip on the contacts for a long time. If something doesn't solder, don't try to solder it the first time. Cool the jar contacts and try again. If all contacts (plus and minus) are tinned, then solder the minus first, then the plus.
Straightening current leads and tinning them on both sides:


We will solder these cans (1, 2 and 4):


We drip flux, pick up solder with a soldering iron tip and press it to the contacts ( don't overheat!)


The current leads are soldered tightly:


You can insulate the terminals with electrical tape:


Lastly we solder the “plus”:


To reduce losses, I recommend bridging the negative current lead with an MGTF wire:


We clean all contacts from acid with alcohol/acetone. If nothing works, briefly turn on the power bank to charge, because The controller is blocked, everything should work:


Next, insert the board into the frame and tighten it with two screws. We secure the negative current lead with the supplied tape, and also fix the temperature sensor:


We insert all this equipment into the aluminum frame and tighten it with screws. Take this double-sided tape or similar:


We cut the strips to the size of the ends of the PB and glue them on:


We slightly tear off the protective film of the tape and use a sharp blade to cut out holes for the ports. You can completely tear off and cut out the tape itself, but the edge of the knife will stick and the result will be worse:


We glue the strips, it turns out like this:


It’s quite easy to glue the other strip; there are no ports there.

Measurement of the “useful capacity” of the modified Xiaomi PB:
The discharge current is 0.95A, the output voltage is also 5.04V (“useful” capacity 4190mah):


The discharge current is 1.7A, the output voltage is also 4.98V (“useful” capacity 4085mah):


As you can see, it’s a little smaller, but the difference in capacity between banks is significant (2000mah vs 3350mah). Well, the test of the “flooded” container:


Let's summarize the performance characteristics of “skeletal” VS “modified”:


That's all, it's up to you to decide whether it's worth redoing. Personally, one single-can cylindrical PB was enough for me, so I didn’t notice any difference from reducing the “useful” capacity. If you live, for example, not in the city, then perhaps this alteration will be unnecessary. At least, my main task when purchasing this PB was completed, namely, “mining” high-capacity cans...


I'm planning to buy +75 Add to favorites I liked the review +79 +154