Knuckles
10 kW
50 pcs 9000 mAh Ni-MH 1.2v Rechargeable C Battery ... $107 USD
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"Real" or "No Real" ???
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9000 mAH NiMH "C" Cell? - WTF!
- Thread starter Knuckles
- Start date
50 pcs 9000 mAh Ni-MH 1.2v Rechargeable C Battery ... $107 USD
Free Shipping from HK!
"Real" or "No Real" ???
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justadad1957
100 W
a wonder what the c rate is for those cells
flip_normal
100 W
No Real!View attachment 1500mah.jpg
BatteryMooch
10 kW
You *might* be able to get 9Ah from that cell.
But only if you discharge at a 10mA rate.
But only if you discharge at a 10mA rate.
At 2 bucks each, those cells don't look all that inviting. I'd rather get used A123 cells from DoctorBass, which aren't as good for Wh/$, but have a much higher C rate, meaning it takes less cells in parallel to make an EV pack.
NiMH in OP
$107 / 50 cells = about $2 / cell
9Ah x 1.2V = 10.4Wh
10.4Wh / $2 = 5.4Wh/$.
A123
$40 / 9 cells = about $4.45 / cell only 9/10 good.
2.3Ah x 3.3V = about 7.6Wh
7.6Wh / $4.45 = 1.7Wh/$
Assume the NiMH is 1C (generous, probably) and you want to run up to 30A at 48V from them, total of 10Ah; you need at least 40s4p
40 x 4 = 160 cells, or $320.
A123 at 10C you could run 15s5p
15 x 5 = 75 cells, or $334.
I'm guessing the NiMH is heavier than the A123, and larger, for the above pack estimates. Not worth the cost difference, to me.
I'd go A123 if I was going to pay that price anyway.
NiMH in OP
$107 / 50 cells = about $2 / cell
9Ah x 1.2V = 10.4Wh
10.4Wh / $2 = 5.4Wh/$.
A123
$40 / 9 cells = about $4.45 / cell only 9/10 good.
2.3Ah x 3.3V = about 7.6Wh
7.6Wh / $4.45 = 1.7Wh/$
Assume the NiMH is 1C (generous, probably) and you want to run up to 30A at 48V from them, total of 10Ah; you need at least 40s4p
40 x 4 = 160 cells, or $320.
A123 at 10C you could run 15s5p
15 x 5 = 75 cells, or $334.
I'm guessing the NiMH is heavier than the A123, and larger, for the above pack estimates. Not worth the cost difference, to me.
I'd go A123 if I was going to pay that price anyway.
Ypedal
100 TW
My nexcell D cell nimh were 8000mah.... not happening in a C cell. ( unless the test equipment is optimistically calibrated hehe )
"optimistically calibrated"....what an "interesting" turn of phrase. I shall have to remember that one.
Velocipede
1 W
- Joined
- Jul 7, 2009
- Messages
- 58
The 2800mAh AA cells I bought on ebay didn't even reach 1000Ah when tested.
My GPS (12-24hours on time with duracell AA) was working only 4 hours.
Also, even the 10000mAh D cells are definitely NOT made to be used at 1C.
My GPS (12-24hours on time with duracell AA) was working only 4 hours.
Also, even the 10000mAh D cells are definitely NOT made to be used at 1C.
liveforphysics
100 TW
They make sub-C sized cells for RC cars that claim 4,500mAh, but actually discharge a real 3.8-4Ah. They can also handle continous 10C discharge. Now days the market is of course dominated by LiPo, so I've not even checked prices on those cells for years, but they used to be about $15-20 per cell.
It does mean it would be possible, or close to possible to make a 7-8Ah C-size cell with a double digit C-rate.
Like others have said, I don't think these are it.
It does mean it would be possible, or close to possible to make a 7-8Ah C-size cell with a double digit C-rate.
Like others have said, I don't think these are it.
dogman dan
1 PW
Oops, did I type 9000? Well the sale is for 900 mha cells.
Ypedal
100 TW
I think they bank on the fact that 99% of buyers don't have equipment or know how to measure capacity.