Go to Post woo hoo! I rigged up brief Internet access using an old wornout robot battery. - Mark McLeod [more]
Home
Go Back   Chief Delphi > Technical > Electrical
CD-Media   CD-Spy  
portal register members calendar search Today's Posts Mark Forums Read FAQ rules

 
Closed Thread
Thread Tools Rate Thread Display Modes
  #1   Spotlight this post!  
Unread 14-01-2012, 13:59
dsalvucci dsalvucci is offline
Registered User
FRC #0023 (PNTA)
Team Role: Driver
 
Join Date: Jan 2012
Rookie Year: 2012
Location: Plymouth
Posts: 15
dsalvucci is an unknown quantity at this point
Battery Performance Curve?

This may have already been asked, but i could not find it.

Does anybody have a performance curve for the standard FRC Battery? We are trying to decide whether or not the battery will actually last 2 minutes with a certain amount of amperage drawn.
  #2   Spotlight this post!  
Unread 14-01-2012, 14:02
Ether's Avatar
Ether Ether is offline
systems engineer (retired)
no team
 
Join Date: Nov 2009
Rookie Year: 1969
Location: US
Posts: 8,125
Ether has a reputation beyond reputeEther has a reputation beyond reputeEther has a reputation beyond reputeEther has a reputation beyond reputeEther has a reputation beyond reputeEther has a reputation beyond reputeEther has a reputation beyond reputeEther has a reputation beyond reputeEther has a reputation beyond reputeEther has a reputation beyond reputeEther has a reputation beyond repute
Re: Battery Performance Curve?

Quote:
Originally Posted by dsalvucci View Post
This may have already been asked, but i could not find it.

Does anybody have a performance curve for the standard FRC Battery? We are trying to decide whether or not the battery will actually last 2 minutes with a certain amount of amperage drawn.
http://www.yuasabatteries.com/pdfs/N..._DataSheet.pdf
  #3   Spotlight this post!  
Unread 14-01-2012, 14:06
dsalvucci dsalvucci is offline
Registered User
FRC #0023 (PNTA)
Team Role: Driver
 
Join Date: Jan 2012
Rookie Year: 2012
Location: Plymouth
Posts: 15
dsalvucci is an unknown quantity at this point
Re: Battery Performance Curve?

Thanks for the quick reply.

I could be entirely wrong but i do not see what i am looking for in those graphs. Does one of those say battery life with the amperage being drawn at say 100A versus 200A? We understand that Ah is 17.2, but we also know the correlation is not linear. We are looking for a graph of that correlation.
  #4   Spotlight this post!  
Unread 14-01-2012, 14:41
Ether's Avatar
Ether Ether is offline
systems engineer (retired)
no team
 
Join Date: Nov 2009
Rookie Year: 1969
Location: US
Posts: 8,125
Ether has a reputation beyond reputeEther has a reputation beyond reputeEther has a reputation beyond reputeEther has a reputation beyond reputeEther has a reputation beyond reputeEther has a reputation beyond reputeEther has a reputation beyond reputeEther has a reputation beyond reputeEther has a reputation beyond reputeEther has a reputation beyond reputeEther has a reputation beyond repute
Re: Battery Performance Curve?

Quote:
Originally Posted by dsalvucci View Post
I could be entirely wrong but i do not see what i am looking for in those graphs.
That's why it's important to frame your question carefully. You made no mention of 200 amps in your original question.

Your battery will be dead or damaged if you try to draw 200 amps for 2 minutes.

  #5   Spotlight this post!  
Unread 14-01-2012, 15:41
Joe Ross's Avatar Unsung FIRST Hero
Joe Ross Joe Ross is offline
Registered User
FRC #0330 (Beachbots)
Team Role: Engineer
 
Join Date: Jun 2001
Rookie Year: 1997
Location: Los Angeles, CA
Posts: 8,599
Joe Ross has a reputation beyond reputeJoe Ross has a reputation beyond reputeJoe Ross has a reputation beyond reputeJoe Ross has a reputation beyond reputeJoe Ross has a reputation beyond reputeJoe Ross has a reputation beyond reputeJoe Ross has a reputation beyond reputeJoe Ross has a reputation beyond reputeJoe Ross has a reputation beyond reputeJoe Ross has a reputation beyond reputeJoe Ross has a reputation beyond repute
Re: Battery Performance Curve?

Quote:
Originally Posted by dsalvucci View Post
Thanks for the quick reply.

I could be entirely wrong but i do not see what i am looking for in those graphs. Does one of those say battery life with the amperage being drawn at say 100A versus 200A? We understand that Ah is 17.2, but we also know the correlation is not linear. We are looking for a graph of that correlation.
The chart titled "NP Discharge Characteristics Curves at 25c" shows it, but not at the high current draws that you want. 1C is the speced discharge rate (17.2 amp hours). You can compare the curves 3C (51.6 a) and 2C (34.4 a).
  #6   Spotlight this post!  
Unread 14-01-2012, 15:41
dsalvucci dsalvucci is offline
Registered User
FRC #0023 (PNTA)
Team Role: Driver
 
Join Date: Jan 2012
Rookie Year: 2012
Location: Plymouth
Posts: 15
dsalvucci is an unknown quantity at this point
Re: Battery Performance Curve?

Ok, thank you. That response was exactly what i wanted.
  #7   Spotlight this post!  
Unread 18-01-2012, 08:03
Unsung FIRST Hero
Al Skierkiewicz Al Skierkiewicz is offline
Broadcast Eng/Chief Robot Inspector
AKA: Big Al WFFA 2005
FRC #0111 (WildStang)
Team Role: Engineer
 
Join Date: Jun 2001
Rookie Year: 1996
Location: Wheeling, IL
Posts: 10,798
Al Skierkiewicz has a reputation beyond reputeAl Skierkiewicz has a reputation beyond reputeAl Skierkiewicz has a reputation beyond reputeAl Skierkiewicz has a reputation beyond reputeAl Skierkiewicz has a reputation beyond reputeAl Skierkiewicz has a reputation beyond reputeAl Skierkiewicz has a reputation beyond reputeAl Skierkiewicz has a reputation beyond reputeAl Skierkiewicz has a reputation beyond reputeAl Skierkiewicz has a reputation beyond reputeAl Skierkiewicz has a reputation beyond repute
Re: Battery Performance Curve?

dsa,
Teams regularly draw more than 200 amps from this battery for short periods of time. The battery is capable of supplying in excess of 500 amps at full charge, again for a short period. However, at the high current, it will not be at 12 volts. In order to accurately predict your result you will need to gather data on how much current is used at certain times. Then using that data you can predict what might actually be your life expectancy. The critical factor is a battery that falls below 5.5 volts. This is the point at which the Crio will disable all output. At less than 4.5 volts, the power supplies on the PD stop working and power to the Crio and radio will fail.
If you are designing your mechanical to use the motor(s) in a high current state, be advised that the breakers cannot supply that current for long and the both Victor and Jag are not designed for sustained high currents.
__________________
Good Luck All. Learn something new, everyday!
Al
WB9UVJ
www.wildstang.org
________________________
Storming the Tower since 1996.
Closed Thread


Thread Tools
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT -5. The time now is 19:02.

The Chief Delphi Forums are sponsored by Innovation First International, Inc.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.
Copyright © Chief Delphi