Arrduino MEGA 2560 R3 with powerbank

Projects General Guidance
1

Hello, my question is if I can use this https://www.xiaomitoday.com/xiaomi-mi-powerbank-2c-20-000mah-review-almost-lower-price-tag/
powerbank with Arduino MEGA 2560 R3? And how do I calculate if this powerbank can handle 2.5 A current? Has anyone experience to help me?

2

360modena_cs:
Hello, my question is if I can use this https://www.xiaomitoday.com/xiaomi-mi-powerbank-2c-20-000mah-review-almost-lower-price-tag/
powerbank with Arduino MEGA 2560 R3? And how do I calculate if this powerbank can handle 2.5 A current? Has anyone experience to help me?

The article you (almost) linked to says:

"Generally, there are three jacks – micro USB input port supporting 5V2A / 9V2A fast charge, and two USB-A output ports supporting 5.1V2.4A / 9V2A / 12V1.5A fast charge."

3

If I use a Lead Acid battery (4500mAh, 6V) instead of powerbank, what is the maximum current I can get?

4

360modena_cs:
If I use a Lead Acid battery (4500mAh, 6V) instead of powerbank, what is the maximum current I can get?

It depends on the load eg the current draw.

V=IR

5

ieee488:
It depends on the load eg the current draw.

V=IR

I didn't ask it correctly. What is the maximum current the battery can give? Can I have 4.5A for 1 hour?

6

360modena_cs:
I didn't ask it correctly. What is the maximum current the battery can give? Can I have 4.5A for 1 hour?

You are maybe confusing current with capacity.

You cannot know (without some measurments and tests) what is the maximum current the battery will supply, although sometimes the manufacturer will state this maximum.

A battery with a capacity of 4500mAhr should be able to supply 4500mA for one hour, or 2250mA for two hours etc.

7

So, a 20000mAh battery can give 20A for 1 hour? Does this make sense?

8

360modena_cs:
So, a 20000mAh battery can give 20A for 1 hour? Does this make sense?

It might provide 20A or it might not, I did say;

"You cannot know (without some measurments and tests) what is the maximum current the battery will supply, although sometimes the manufacturer will state this maximum"

You could for instance have a 20000mAhr battery that will only put out 2A maximimum.

9

Clever sales dudes put the (inflated) battery rating on a powerbank.

But that powerbank has to convert the ~3.7volt internal battery to 5volt USB.

That will decrease the Ahr rating by ~25%, not counting the losses in the boost converter.

Continuous max current draw of a powerbank is limited by that boost converter, not by the battery.

Powerbanks are designed to charge another device.
Most of them have an automatic shutoff when current draw falls below a certain value (device is charged).
That could be a hassle when you want to power an Arduino.
Leo..