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Too good to be true 18650 9900mah?

1186 Views 5 Replies 5 Participants Last post by  skyguy_6153
Keep seeing these on ebay, 9900mah so a bit ridiculous.

I wonder what safety testing they have done on them lol

https://www.ebay.co.uk/itm/4pcs-3-7...965952?hash=item4b141c9a00:g:NY0AAOSwZ8ZW8M3K

if these are 3.7v, if i bought a 1000 of them would i have a 3700v battery pack or a 370 volt pack?
or does it not work like that?
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if these are 3.7v, if i bought a 1000 of them would i have a 3700v battery pack or a 370 volt pack?
or does it not work like that?
A thousand of any cell in series is a thousand times the voltage... but a 3700 V and 10 A-h pack is not useful. A more useful arrangement would be to connect groups of ten in parallel (for ten times the capacity but the same voltage), then a hundred of those groups in series, to be a 370 V and 100 A-h pack with the same thousand cells (if they were actually 10 A-h cells :rolleyes:).
 

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9900 mAh is fake, and made in China, and unsafe to use. Most likely sold as a flashlight battery.

It is probably about 2,000 mAh, if you are lucky.

A flashlight mAh = 1/5 mAh approx. LED flashlights use 1/5 of the current of an incandescent flashlight, thus comparatively the flashlight will last 5x longer, and 9,900 flashlight mAh is equivalent to about 2,000 mAh with an incandescent lamp. There is no such standard, but this would be the alibi of the distributor of these fake cells.
 
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