battery q?

Old 03-24-2011, 11:04 AM
  #1  
Tech Adept
Thread Starter
 
Join Date: Feb 2011
Posts: 208
Default battery q?

if i run a 25c battery would i get more out of a 40c battery? or are thay so close i would not see any dif? (at the same size mah)
its a 17.5 t motor
urban is offline  
Old 03-24-2011, 11:27 AM
  #2  
Tech Elite
iTrader: (24)
 
Join Date: Nov 2002
Location: NY/FL
Posts: 3,378
Trader Rating: 24 (100%+)
Default

Depends on who you talk to. You're going to get a million opinions. Also depends what class racing you're doing. I run Can motor mini, vta and usgt and don't find any need to have more than 25c. That being said....now that the cost has gone so low on good lipo batts, I'll probably start buying 4-5000mah with 30-40c ratings. Check www.hobbypartz.com for "roar approved" batteries. They have some awesome deals on the Gens Ace 2s batteries.
Evoracer is offline  
Old 03-24-2011, 11:31 AM
  #3  
Tech Elite
iTrader: (37)
 
jlfx car audio's Avatar
 
Join Date: Nov 2007
Location: jackson,tn
Posts: 3,834
Trader Rating: 37 (100%+)
Default

Originally Posted by urban View Post
if i run a 25c battery would i get more out of a 40c battery? or are thay so close i would not see any dif? (at the same size mah)
its a 17.5 t motor
I'm probably goin to start a pissing match. But on a 17.5 spec a 25 c batt will perform equally as a 40c or so. Only cause the amp draw of a 17.5 is able to warm up a 25c pack enough to hold a higher voltage better. A 40c pack will drop off slightly more only cause the pack never gets any heat in it.
a lipo will perform much better and hold a higher voltage with a warm /hot pack. But its risky when pack starts gettin to hot. But will not have a issue 25c on 17.5
jlfx car audio is offline  
Old 03-24-2011, 11:37 AM
  #4  
Tech Elite
iTrader: (24)
 
Join Date: Nov 2002
Location: NY/FL
Posts: 3,378
Trader Rating: 24 (100%+)
Default

Originally Posted by jlfx car audio View Post
I'm probably goin to start a pissing match. But on a 17.5 spec a 25 c batt will perform equally as a 40c or so. Only cause the amp draw of a 17.5 is able to warm up a 25c pack enough to hold a higher voltage better. A 40c pack will drop off slightly more only cause the pack never gets any heat in it.
a lipo will perform much better and hold a higher voltage with a warm /hot pack. But its risky when pack starts gettin to hot. But will not have a issue 25c on 17.5
OMG ! common sense DOES exist ! Just a note that it's not really the motor that draws, it's the ESC. The motor only get's what the esc can supply.
Evoracer is offline  
Old 03-25-2011, 01:39 AM
  #5  
Tech Fanatic
iTrader: (14)
 
ozzy-crawl's Avatar
 
Join Date: Aug 2009
Location: Forde A.C.T
Posts: 990
Trader Rating: 14 (100%+)
Default

Originally Posted by Evoracer View Post
OMG ! common sense DOES exist ! Just a note that it's not really the motor that draws, it's the ESC. The motor only get's what the esc can supply.
ok here goes some common sense out the window
a motor is not limited by the esc as much as most think,a motor will take what ever it can get until either the motor/esc/batteries let out the magic smoke.
if you take a motor designed for 300 watts at 7.4 volts its around 40 amps
if you jam 2-3 times the voltage at it you can and will pull 2-3 times that amp draw.
i have data logged 300 watt motors over 2000 watts when fed enough volts
just not for very long.
the esc is not much more than a gate between the battery and motor.
as for batteries a 40c usually wont make much difference at such low amp draw
if there is any difference its because a 40c will have slightly less resistance unless both packs are pre heated
ozzy-crawl is offline  
Old 03-25-2011, 01:43 AM
  #6  
Tech Addict
iTrader: (18)
 
calif_bouncer's Avatar
 
Join Date: Jan 2011
Location: vandenberg village
Posts: 541
Trader Rating: 18 (100%+)
Default

i got a headache!
calif_bouncer is offline  
Old 03-25-2011, 03:09 AM
  #7  
Tech Rookie
 
Join Date: Feb 2011
Posts: 5
Default

Originally Posted by jlfx car audio View Post
I'm probably goin to start a pissing match. But on a 17.5 spec a 25 c batt will perform equally as a 40c or so. Only cause the amp draw of a 17.5 is able to warm up a 25c pack enough to hold a higher voltage better. A 40c pack will drop off slightly more only cause the pack never gets any heat in it.
a lipo will perform much better and hold a higher voltage with a warm /hot pack. But its risky when pack starts gettin to hot. But will not have a issue 25c on 17.5
40C will be much punch.
sammiegra is offline  
Old 03-26-2011, 04:29 AM
  #8  
Tech Adept
iTrader: (6)
 
Join Date: Oct 2009
Posts: 176
Trader Rating: 6 (100%+)
Default

Originally Posted by ozzy-crawl View Post
ok here goes some common sense out the window
a motor is not limited by the esc as much as most think,a motor will take what ever it can get until either the motor/esc/batteries let out the magic smoke.
if you take a motor designed for 300 watts at 7.4 volts its around 40 amps
if you jam 2-3 times the voltage at it you can and will pull 2-3 times that amp draw.
i have data logged 300 watt motors over 2000 watts when fed enough volts
just not for very long.
the esc is not much more than a gate between the battery and motor.
as for batteries a 40c usually wont make much difference at such low amp draw
if there is any difference its because a 40c will have slightly less resistance unless both packs are pre heated
How and what do you use to preheat battery packs?
Sorry bloke first time I ever heard that
emerge is offline  
Old 03-26-2011, 06:03 AM
  #9  
Tech Regular
 
getpip's Avatar
 
Join Date: Jan 2008
Posts: 369
Default

This..
http://www.muchmoreracing.net/us/detail/mm-wt2.htm

Some people use baby bottle warmers. (cheaper)

Just because you've not heard of it doesn't mean it's not so.
getpip is offline  

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are Off


Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service - Do Not Sell My Personal Information -

Copyright 2018 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.