R/C Tech Forums

Go Back   R/C Tech Forums > General Forums > Radio and Electronics

Reply
 
Thread Tools Search this Thread
Old 04-02-2010, 05:55 AM   #1
Tech Addict
 
Join Date: Aug 2005
Location: Sydney, Australia
Posts: 549
Trader Rating: 31 (100%+)
Default LiPo Batteries - Help a Noob

Ok guys bear with me here, I'm new to LiPo batteries, just trying to get back into racing 1/12 and touring car and I need new batts. Whats the go with all the numbers? 40C 50C etc? whats the 1 cell? 2 cell?

I've seen them around, in tourers, but what are the smaller ones in the 1/12th scale cars?

Is there a good link to where I can go and read up about them or get some info with regards to chaaging/discharging/balancing???

Any help appreciated.
Daniel
$$$... is offline   Reply With Quote
Old 04-02-2010, 06:41 AM   #2
Tech Master
 
Join Date: Jan 2009
Posts: 1,779
Trader Rating: 2 (100%+)
Default

Quote:
Originally Posted by $$$... View Post
Ok guys bear with me here, I'm new to LiPo batteries, just trying to get back into racing 1/12 and touring car and I need new batts. Whats the go with all the numbers? 40C 50C etc? whats the 1 cell? 2 cell?

I've seen them around, in tourers, but what are the smaller ones in the 1/12th scale cars?

Is there a good link to where I can go and read up about them or get some info with regards to chaaging/discharging/balancing???

Any help appreciated.
Daniel
lots of info here:

http://thetoyz.com/forums/index.php?showtopic=26695

http://thetoyz.com/forums/index.php?showtopic=6532
__________________
Powered by: MASTERCARD and VISA

If you're in control, you're not driving it fast enough!

XRAY / NOVAROSSI / SANWA / AKA TIRES / BYRON FUEL
ganymede is offline   Reply With Quote
Old 04-02-2010, 06:58 AM   #3
Tech Lord
 
Join Date: Jul 2008
Location: Houston, TX
Posts: 11,530
Trader Rating: 21 (100%+)
Default

The "S" number is the number of cells wired in series and wiring in series causes voltage to add. Each lipo cell is 3.7v nominal so a 2S lipo is two 3.7v cells wired in series so the volltage is 3.7 + 3.7 - 7.4v nominal.

Lipo deal with 3 diff, somewhat confusing voltages. There is the nominal voltage - this is primarily used to talk about lipos - 2S is 7.4v, 3S is 11.1v 6S is 22.2v etc. When you charge a lipo cell, it reaches the cell maximum voltage of 4.2v/cell so a freshly charged 2S will read 2 x 4.2v = 8.4v, a 3S will be 12.6v anf a 6S will be 25.2v fully charged. Lipo cell max imum voltage is 4.2v/cell and can be damaged by overcharging to higher voltages. This is the reason a lipo capable charger is different and important to have and use. It avoids potential overcharging lipos.

There is also a minimjum lipo cell voltage that is important since if you discharge the cell below the minimum, there is potential for damaging the cell (it can swell up like a balloon) rendering the cell/lipo unsafe to use further. This minumim is about 3v/cell. A low voltage cutoff usually in the esc protects the lipo from overdischarging. There are separate lvc if you're using an esc without one.

The "C" rating as its called is the lipos discharge capability. Its a way of rating what the lipo battery can discharge - it is a function of capacity (mah) and the C rating. A 5000mah 40C lipo can discharge 5000/1000 x 40 = 200amps. Similarly a 50C 5000mah lipo can discharge 250amps. The C rating is also used in charging as in a lipo is rated for 2C charing - this means you can safely charge A 5000mah lipo AT 5000/1000 x 2 = 10amps, A 3 C charge would be 15amps. The higher the C allowed for charging, the shorter the charge time.


Here's some more detail -

http://www.rchelicopterfun.com/rc-lipo-batteries.html
Duster_360 is offline   Reply With Quote
Reply

Similar Threads
Thread Thread Starter Forum Replies Last Post
Damnit, the lipo battery industry needs better standards! Freezebyte Electric Off-Road 130 06-20-2017 10:07 AM
1/10 scale Onroad electric NEED HELP/ADVICE danny7878 Rookie Zone 9 10-04-2009 04:26 PM
Onroad electric NEED HELP/ADVICE danny7878 Electric On-Road 9 09-23-2009 09:14 PM
Mini Inferno half eight help !!! Mini^Inferno Micro and Mini Scales 17 01-20-2009 03:31 PM



Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search

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



All times are GMT -7. It is currently 04:56 PM.


Powered By: vBulletin v3.9.2.1
Privacy Policy | Terms of Use | Advertise Content © 2001-2011 RCTech.net