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Unread 09-09-2009, 22:48
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Re: Average Energy per match

Quote:
Originally Posted by Stephen Kowski View Post
My main interest in knowing the average energy was to see if a) this battery is overkill and b) if something like an ultracapacitor stack could replace it since there is no significant capacity fade associated with a UC stack (among other benefits).
With my back-of-the envelope calculation of 9 Ah, I think we're in the ballpark as far as energy supply goes. I suppose a team could theoretically use as much as 120A for 2.3 minutes (= 4.6 Ah), but with a discharge current like that the battery's capacity is exceeded (the curves only go up to 51A, I am extrapolating). The conclusion is that there's a reasonable amount of energy, but not a large excess.

As for Ultracaps, that amount of energy might be a bit expensive. Here's a Datasheet for the BCAP3000-P270-T04, a 3 kiloFarad 2.7 volt capacitor that lists for $130. You'd need not less than five to come close to that $37 MK battery. I agree, they are rated for a million cycles - the FiM model may expand to make this useful - but at this time, cost is a significant obstacle.

To put it another way: It's not a bad idea, but you can buy an awful lot of lead-acid capacity for that money.
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