Author Topic: Rattling AA NIMH Batteries  (Read 7779 times)

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Offline dexters_labTopic starter

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Rattling AA NIMH Batteries
« on: October 17, 2014, 11:38:30 am »
 :wtf:

just bought 20 of these off ebay, some of them rattle... hmm, i'm suspicious now but they all have circa 1.2v on them.

going to disassemble, what will i find inside, an even cheaper AAA?

place your bets NOW!

will post results in a day or so!

Offline SeanB

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Re: Rattling AA NIMH Batteries
« Reply #1 on: October 17, 2014, 05:33:37 pm »
Sub N cell and a short spring to keep it in contact. Most likely the cell is also a recycled cell from a cordless phone or other ilk that uses those tiny cells.
 

Offline tom66

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Re: Rattling AA NIMH Batteries
« Reply #2 on: October 17, 2014, 07:45:14 pm »
100mAh LiPo with a 3V series zener diode  :-DD
 

Offline SeanB

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Re: Rattling AA NIMH Batteries
« Reply #3 on: October 17, 2014, 07:56:01 pm »
I have seen some made by taking a regular AA cell, cutting it into sections then putting wires to the plates and then rolling it back up and putting into the housing with a few drops of fresh KOH electrolyte.
 

n45048

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Re: Rattling AA NIMH Batteries
« Reply #4 on: October 17, 2014, 08:50:51 pm »
BTY? Sounds like a reputable brand ;-)
 

Offline dexters_labTopic starter

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Re: Rattling AA NIMH Batteries
« Reply #5 on: October 22, 2014, 05:54:46 pm »
ok, SeanB was closest to the mark

they are simply very low capacity internals with a weight in the bottom to make them feel weighty like a battery should!


Offline dexters_labTopic starter

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Re: Rattling AA NIMH Batteries
« Reply #6 on: November 01, 2014, 12:46:46 pm »
short follow up, detailing the capacity of these fake batteries.


Offline HighVoltage

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Re: Rattling AA NIMH Batteries
« Reply #7 on: November 01, 2014, 02:24:38 pm »
I had the same experience with some Duracell batteries.
Turned out to be fakes...
Returned them all to the ebay seller.

Who would ever have expected this kind of ripoff 20 years ago.
There are 3 kinds of people in this world, those who can count and those who can not.
 

Offline dexters_labTopic starter

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Re: Rattling AA NIMH Batteries
« Reply #8 on: November 01, 2014, 04:06:45 pm »
i am in discussion with the seller about these batteries, they dont want to admit they are faulty, they seem more concerned about what kind of charger i'm using. Crazy considering i showed them the video of the insides!

they either know they are selling a misrepresented product or they are not spot quality checking what they are selling, no excuse for either IMO

Offline SeanB

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Re: Rattling AA NIMH Batteries
« Reply #9 on: November 01, 2014, 05:44:06 pm »
The 2300mAh is the total capacity you can expect to get out of the cells in the whole of their life. they just did not tell you that.
 

Offline dexters_labTopic starter

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Re: Rattling AA NIMH Batteries
« Reply #10 on: November 01, 2014, 06:22:20 pm »
 :-+ 12 charge cycles, probably not far off!

Offline amyk

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Re: Rattling AA NIMH Batteries
« Reply #11 on: November 02, 2014, 05:19:00 am »
200-300mAh seems to be about right if you search online for others who have tested the actual capacities of "BTY" cells. The trick is that they never actually say "mAh", so they can claim that "2300" is their model number and not their capacity.

The brand is "BTY" because they're missing an A, a T, an E, and an R... :-DD
 

Offline HighVoltage

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Re: Rattling AA NIMH Batteries
« Reply #12 on: November 02, 2014, 06:05:21 pm »
so they can claim that "2300" is their model number and not their capacity.

It seems to be the modern thing to do.

I bought an anvil on ebay last year and it was stated to be a 10 kg anvil.
So, I expected a 10 kilogram anvil to arrive and when I got it it put only 9 kg on the scale.
I complained to the seller and he told me, that "10 kg"  did not refer to the weight of the anvil, it was only its name.
Well, what can you argue against that one?

 
There are 3 kinds of people in this world, those who can count and those who can not.
 

Offline G7PSK

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Re: Rattling AA NIMH Batteries
« Reply #13 on: November 02, 2014, 09:40:59 pm »
Yes you can as traditionally anvils are sold by weight.
 

Offline SeanB

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Re: Rattling AA NIMH Batteries
« Reply #14 on: November 03, 2014, 06:31:04 pm »
10kg* Anvil.

*= including packaging.................

To cure the description simply repeatedly apply the difference to the offending seller's digits while they are held on the anvil, using a hammer of the mass of the difference applied from 2m height.

 

Offline Fraser

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Re: Rattling AA NIMH Batteries
« Reply #15 on: November 03, 2014, 07:01:03 pm »
I have given up buying rechargeable batteries from China. I got burnt on six 14.4V battery packs that weighed so little that I wondered whether there was anything inside the cells. Capacity was supposed to be 1800mAh which seemed realistic when bought but true capacity proved to be less than 400mAh  :(

I now buy most of my batteries from the Component Shop and have yet to receive a dud. VAPEX is the brand that they sell and they will build custom packs to order.

http://www.componentshop.co.uk/

« Last Edit: November 03, 2014, 07:17:39 pm by Aurora »
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