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Unread 12-03-2014, 17:28
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Jon Stratis Jon Stratis is offline
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FRC #2177 (The Robettes)
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Re: Battery Model Number Questions.

Quote:
Originally Posted by Ether View Post

What's the big difference in the specs?

The max amps? Take a look at the 360 max amps for the ES17-12.

The Ah? Take a look at the discharge curves for the SP12-18HR vs SP12-18. They are identical.

I agree that the graphs on the second page are identical, which doesn't seem to make much sense to me, as the data on the first page (specifically the tables) is different. The differences I see are:

- weight
- Rated Capacity
- Max Discharge Current
- "Constant Current Discharge" table values
- "Constant Power Discharge" table values

I'm a software engineer, not chemical or electrical, and frankly, the details of how all of those numbers impact robot performance is a bit beyond me - That's probably why FIRST asks teams to e-mail for approval for an equivalent battery. They can't rely on all of the LRI's having the ability to judge battery data sheets to determine if a battery is equivalent for our purposes.

That said, from the two tables, it appears that you can pull more current/power from the HR battery over an equivalent discharge time period. To me, that seems to indicate a difference that might be noticeable on a robot.
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