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Randymanme
November 29th, 2020, 12:21 PM
In advertisements, I've seen what appear to me to be some very large mAh capacities on some portable smartphone chargers. Plus, there appears to be inordinate price fluctuations.

For example, on a single webpage, there may be a "300,000 mAh dual usb portable solar battery charger solar power bank" for $15.99 (USD), as well as a "6,700 mAh Portable Charger for Most USB-Enabled Devices" for $31.99 (USD).

Am I missing something here?

jeremy31
November 29th, 2020, 12:36 PM
Moved to the Cafe

GhX6GZMB
November 29th, 2020, 04:32 PM
mAh only make sense for the batteries themselves, the SI-unit is joule (J), but is seldom used.

For a charger, such a specification is completely meaningless and probably only made to confuse the issue: "Wow!, what a big number!".

poorguy
November 30th, 2020, 03:52 PM
Perhaps this will explain.

https://chargetech.com/how-much-mah-do-i-need-in-a-portable-charger/

https://www.tp-link.com/us/support/faq/741/

http://www.learningaboutelectronics.com/Articles/mAH-of-a-battery.php

CatKiller
November 30th, 2020, 05:14 PM
Why would capacity be the defining characteristic of cost? Should a bucket cost 100× as much as a Thermos flask?

There is a lot of technology in a modern battery, very little of which is to do with how much goo they've put in it.

GhX6GZMB
November 30th, 2020, 09:51 PM
Perhaps this will explain.

https://chargetech.com/how-much-mah-do-i-need-in-a-portable-charger/

https://www.tp-link.com/us/support/faq/741/

http://www.learningaboutelectronics.com/Articles/mAH-of-a-battery.php

No, it won't.
The first link is googledygook. Chargers do not supply mAh, they supply current (mA) at a suitable voltage (V). Equals power. Period.
The second is about power banks, which are also batteries, not chargers (although they can be used to charge another battery).
The third is not too far off, but is unable to use SI units. mAH translates to milliampere*henry which is ridiculous.

In my first post, I simplified the explanation by using joule (J) as the relevant SI unit, which is not 100% correct. It assumes that the battery's operating voltage stays within range. The 100% correct SI unit is coulomb (C) which no one would use in this situation (who'd discharge a battery to 0 V?).

Marketing bull and obfuscation at its worst. Also called "mushrooming".

kurt18947
December 1st, 2020, 01:47 AM
Marketing bull and obfuscation at its worst. Also called "mushrooming".

That's what it seems like to me. 1 amp hour = 1000 milli amp hour. Something that has a 1000 of x HAS to be better than something that has only 1 of x, doesn't it? Taking advantage of consumer ignorance.

poorguy
December 1st, 2020, 04:18 AM
No, it won't.
The first link is googledygook. Chargers do not supply mAh, they supply current (mA) at a suitable voltage (V). Equals power. Period.
The second is about power banks, which are also batteries, not chargers (although they can be used to charge another battery).
The third is not too far off, but is unable to use SI units. mAH translates to milliampere*henry which is ridiculous.

In my first post, I simplified the explanation by using joule (J) as the relevant SI unit, which is not 100% correct. It assumes that the battery's operating voltage stays within range. The 100% correct SI unit is coulomb (C) which no one would use in this situation (who'd discharge a battery to 0 V?).

Marketing bull and obfuscation at its worst. Also called "mushrooming".
@ml9104
If you actually read the article instead of just the title you would see the article is referring to portable chargers which are battery packs and I quote the first paragraph from the link.

https://chargetech.com/how-much-mah-...table-charger/
(https://chargetech.com/how-much-mah-do-i-need-in-a-portable-charger/)
"Two major factors that must be considered when deciding how much mAh (power) you need in a portable charger (https://chargetech.com/portable-power-banks/) are usage and time. If you use your phone as much as the rest of us, then you are well aware of the woes of a drained battery. Nowadays, it is essential to have a portable charger readily accessible in order to skip the annoyance of searching for an available AC outlet."

If you would have actually read the article ml9104 then you would have seen that the article speaks of portable chargers which are batteries and are rated in mAh.

The whole article is about portable chargers which are batteries that are used to charge portable devices and which is what the OP was asking about.

GhX6GZMB
December 1st, 2020, 10:02 PM
Admittedly. The detail about "portable" escaped me. Perhaps because the first sentence:
"Two major factors that must be considered when deciding how much mAh (power)"
turned me off.

grahammechanical
December 3rd, 2020, 05:38 AM
The difference in prices could be related to the difference in materals and build quality. But then again it may be due to brand name.

A corporation with a fashionable brand name could have its products made in a country where, labour costs are low and still change a high price because of a desire to make massive profits from a consumer base that is emotionally locked in to their brand name.

Another corporation lacking brand name awareness and a large consumer base may settle for lower profit margins in order to sell its products.

As for the differences in electrical output that could be explained by comparing a charger designed for a single device and one designed to charge multiple devices. There is often a difference in quality of materials along with build quality between consumer grade products and industrial grade products.

Some companies do not sell products designed to last for decades. It is their policy to continually release new products to keep the consumer paying for new products. Other the other hand some commercial enterprises make purchasing choices based on how long a product is reasonably expected to last.

You give us two comparison points. Specifications would give much more information about both products. But that would go beyond the simple discussion that we are having here.

Regards.