How to Know Your Power Bank Are Good Quality

We all know that the power bank said Capacity cannot charge your smart phone simple divided your cell phone battery power.

Every power bank have a conversion rate. High end power banks boast to have 90% power conversion rate. Actually, mostly it works between 80-90% conversion rate. The 90% conversion rate of an mobile power bank is the experimental data.

Let find out this result.

First, we need to know the 3 physics factor: voltage,  current, energy conservation law.

Second, conver the power bank capacity into large cell phone battery capacity. Like a bucket with water. From Small Size one to big size one. The power bank battery is 3.7V, while the cell phone device battery is 5V, so let's convert.

Take a example, we have a 3350mAh power bank in hand, (many brand like Anker, Poweradd,you could easily find this kind power bank on Amazon ), it is small power bank, can it be really stands good for you? Let know how it charge your cell phone.

3350mAh x 3.7V = 12.395WH

So when conver to 5V it is 12.395Wh / 5V = 2479mAh

Third, let assume, it is perfect 100% conversion rate, this kind power bank it only has 2479mAh, it could only charge your iphone less 1.5times. 

Conclusion, we all knows that, energy losing during charging your cell phone, no way for charging without lossness.

Even though, most brand boast their power bank have a high conversion rate to 90%. But we should keep in mind, they just cheat us. It is an experimental data, useless in actual using.

So, where the consuming lead to power bank low conversion rate be so low?

1) The power bank capacity lost. Say, you put a full bucket water, it will vaporizing, water will be less. The power bank vaporizing fast and more obviously.

2) During charging, the product it self heating, capacity lost.

3) Power Bank Inside IC and charing cable consuming, capacity lost.

Actually, this 3 factor, it will almost consume 10% of the total capacity.

So during our using. the power bank capacity will be only around 80%.

Till now, we could understand, when will buy the power bank. It advertised power bank could charging the iphone 1.5times. while during our using, it could just chaarging 1 times, and a little bit capacity left. At that moment you should go to charging your power bank. 

Do not drain your power bank juice total clear, at the last moment, the power bank voltage sharp jump down, it does harm to your power bank.

So we just keep in mind, acutal power bank conversion rate is about 80% in real life using.