Question Power Bank usage. Approx lasting time on full charge on a Pirate Radio Zero W and a Pi 3 Model B+

[Mark1985]

Hi, I'm using a Pirate Radio On Zero W with a Power Bank (500,000mah 5.0v 2.1a (max is 2.1a). This one, https://www.ebay.co.uk/itm/174045226129
Can someone tell me how long it will last for on (approx) on full charge, as I was expecting it to last for a very long while as the % is dropping quicker than I expected it to. Such as it went from 100% to 98% within 5 minutes!!!
I ask as I did use another power bank on it, a Anker power bank (different one) with 26,800mah (max of 3.0a on each port) and it lasted on there for a very, very, very long time! It doesn't have a % meter on there.

I also got a PI 3 B+ model with a Phoniebox (http://www.phoniebox.de)and it goes down quickly on that also. 1% every 5 minutes or so.

I always through the higher the mah, the longer they will last for...
Not an expert really when it comes to them.

 

[kanewolf]

Hi, I'm using a Pirate Radio On Zero W with a Power Bank (500,000mah 5.0v 2.1a (max is 2.1a). This one, https://www.ebay.co.uk/itm/174045226129
Can someone tell me how long it will last for on (approx) on full charge, as I was expecting it to last for a very long while as the % is dropping quicker than I expected it to. Such as it went from 100% to 98% within 5 minutes!!!
I ask as I did use another power bank on it, a Anker power bank (different one) with 26,800mah (max of 3.0a on each port) and it lasted on there for a very, very, very long time! It doesn't have a % meter on there.

I also got a PI 3 B+ model with a Phoniebox (http://www.phoniebox.de)and it goes down quickly on that also. 1% every 5 minutes or so.

I always through the higher the mah, the longer they will last for...
Not an expert really when it comes to them.

I don't believe the 500,000 mah on that battery. That would be a 500 amp hour battery. Google 500 amp hour battery. They are huge. I would recommend getting a USB ammeter and measuring your actual usage.

 

[OldSurferDude]

This is a typical power bank/battery con. The name of the product is "500000mAh Power Bank Backup LED Portable Battery Charger For All Moblie Phone" and the 500000mAh has nothing to do with its energy capacity. (Notice poor grammar and spelling, that's a hint of a bogus product.)

Get, as Kanwolf suggested, a USB V, A, mAh measuring device. A great tool to have. Takes a month or two to receive it from AliExpress.

Once you have the device, you can see how much your RPi is pulling (probably less than an amp). Then you can use it to measure the true capacity and efficiency of the power bank. The latter measurement will take a while.

I have found that there are very few, if any, power banks that live up to their advertising. My testing shows that the more reputable sellers' devices take 80% of nameplate to charge for 55% of nameplate delivered.

The other problem I have with power banks is that they shut off once the current falls below ~40mA. So they are useless with Arduino's because Arduino's only pull ~25mA. I would have liked to have had my Arduino run for two weeks with a 10,000mAh device.

 

[OldSurferDude]

I have a request of you, Mark. Go back to eBay and leave a review. I can't because I didn't buy the item. I looked at the reviews and not one of them noticed what you did. The term is called "astroturfing". It means that the reviews are glowing, but come from only the seller or a service that astroturfs for the seller.