Good power bank?

Question

Batteries

I choose a good and not very heavy power bank.
Stopped at this .
But here's what confused, this battery is 20100mAh, but the description says: 20100mAh charges an iPhone 6S & 6 almost 8 times;
Capacity 6s - 1715mAh; Therefore 1715mAh * 8 = 13720mAh;
Not quite literate in this matter, but why can a battery with a capacity of 20100mAh give ~ 13720mAh?

Answer 1

Most power banks have 18650 batteries. Caring Chinese often put the cheapest and most miserable batteries in order to increase profits. You can write anything, even a million mAh.
By the way, according to the link, the power bank will weigh around half a kilo (1 battery is 70 grams, there are 7-8 of them inside), this somewhat contradicts the "not very heavy" criterion.
All these units are in mAh - one could just as well write "capacity 150 parrots". To begin with, the power bank gives out 5 V of voltage. And the batteries inside are at 3.0 - 4.2 V, the boost converter loses 5-10% of energy. Then the opposite happens, the phone makes 4.2 from 5 V to charge its battery. Again losses. Further - if the batteries in the power bank are not connected in parallel, but in series, they get a higher voltage, BUT when connected in series, mAh do not sum up, but remain the same, there would be no way to measure everything in watt-hours, damn it.
So. As for the choice of charging. We are looking for a DIY case with interchangeable 18650, for the required number of cans (well , for 8 cans, which, IMHO, is an overdofiga, I use boxing for 4 banks), then we look for really high-quality batteries on forums and sites, for example, LG 3500mah , put them in the box and rejoice.

Answer 2

>>> Not quite literate in this matter, but why a battery with a capacity of 20100mAh can give ~ 13720mAh
1. Chinese parameters - they are so Chinese. Too high parameters.
2. There are always losses. For example, voltage conversion losses. Feel the devices in operation - and the battery and smartphone will warm up. Heat is also energy, energy that disappears. But in this case - suspiciously high losses.
3. If we are talking about a lightweight plastic case, then you should be guided in the capabilities of the battery by weight. If the battery (of the same type of course) is more capacious, then it is also heavier . This is banal physics and chemistry.

Answer 3

Good charger.
But I like it better - Wireless Power Bank CGPower.

Answer 4

I don't know about 20000 mAh. With them, problems at the airport can be due to capacity, they will not be allowed on board. I took Ali in the official Xiaomi Power Bank 2 store for 10000 mAh for myself, and no complaints, it has been working for the third year. Charge for 6 is enough. I wrote a review on it on the YouTube channel, so I wanted to describe it) Description and link to the Mail cloud was uploaded https://cloud.mail.ru/public/F3sw/4Bxy8hA4E and to Yandex disk https://yadi.sk/d/RSrQu41eF665zw look at health. Then, by the way, he took his second wife (but with two usb connectors), then a Xiaomi bracelet, in short, now half a house of their production technology. The company is fire!

Answer 5

Michael, then we will advise you such an article about warming up the domain and this one about the resuscitation of the database .

Answer 6

If you do not have confirmation of the consent of the people on this list to receive your newsletter, then I do not recommend that you do this. If only because it is an offense that can have consequences.

Answer 7

Ask on anti-chat , they will prompt you more likely.