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"C" Ratings for Kokam...

Old 08-10-2004, 05:16 AM
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bob_nj
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Default "C" Ratings for Kokam...

On the FMA site, the listing for the SHC Kokams give two ratings. I'm wondering if someone can explain the difference.
The cells are rated at 20C, and support 6.8A continuous discharge.
What exactly does that mean_bob
Old 08-10-2004, 09:24 AM
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ChuckAuger
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Default RE: "C" Ratings for Kokam...

They must be 340 Mah cells. 20 X .340 = 6.8

The 20C means they can be discharged at 20 times the cell capacity. With a cell capacity of .340 Ah, they can be discharged at 6.8A.
Old 08-10-2004, 09:38 AM
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bob_nj
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Default "C" Ratings for Kokam...

Duhhh[:-] It was too early to think I guess. Thanks Chuck...
Old 08-10-2004, 12:27 PM
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Matt Kirsch
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Default RE: "C" Ratings for Kokam...

Your next question would probably be, why bother with the "C" rating when you could just as well specify raw Amps? Well, with the C rating, you don't have to memorize the continuous current each and every size of battery can maintain. All you need to know is that that particular series of Kokams (SHC) can maintain a 20C continuous current. It's more useful when there are more than one or two sizes of cell in a series, like with Tanic, Irate, Thunder Power, Etec, and others, but it's the de-facto standard that the hobby has adopted.
Old 08-12-2004, 03:37 PM
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Greg Covey
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Default RE: "C" Ratings for Kokam...

In the past, a 10C continuous discharge rating was considered unbelievable. Now it is commonplace among many Lithium brands.

Other cell generations now exist for 15C and 20C continuous discharge.

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