You have it right, 1m ohm for the cells and 2.71m ohm for the bussbar.
Are you reading 3.71m ohms IR for each pair in your pack?
The actual IR of the cells can vary, though one would hope not by much.
As long as the bussbars are all the same, and the connections are all clean
and tight (and stay that way), the contributed resistance should be same for
each pair of cells.
The BMS should show the cell IR vary quite a bit with temperature.
Good luck with your Lithium pack.
Al
----- Original Message -----
From: "Buddy Mills" <[email protected]>
To: "'Electric Vehicle Discussion List'" <[email protected]>
Sent: Wednesday, November 27, 2013 5:43 PM
Subject: [EVDL] LiFePO4 internal resistance
Happy Turkey Day,
So my question is.if I have two batteries hooked in parallel and the
internal resistance for one battery is 2m ohm. Is the correct resistance
for both now 1m ohm? I am working with my new Orion BMS and I can
compensate for the busbars in the program. It is reading 3.71 m ohms per
connection which is two batteries in parallel. So is my real resistance 2
m
ohm? 4m ohms or 1m ohms is my query. I believe it is like any other two
resisters in parallel and my new resistance is 1m ohm per set. Which
means
my busbars are contributing 2.71m ohms.
Thanks in advance for any help.
Buddy Mills
<mailto:[email protected]> [email protected]
Look mom, no gas. <http://www.evalbum.com/2887>
http://www.evalbum.com/2887
Disclaimer: No animals were harmed or killed in the process of writing
this
email. Any stories to the contrary are, for the most part, either
fictional
or greatly exaggerated.
-------------- next part --------------
An HTML attachment was scrubbed...
URL:
<http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20131127/daf4b76b/attachment.htm>
_______________________________________________
UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
http://lists.evdl.org/listinfo.cgi/ev-evdl.org
For EV drag racing discussion, please use NEDRA
(http://groups.yahoo.com/group/NEDRA)
_______________________________________________
UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
http://lists.evdl.org/listinfo.cgi/ev-evdl.org
For EV drag racing discussion, please use NEDRA
(http://groups.yahoo.com/group/NEDRA)
