|
Matronics Email Lists Web Forum Interface to the Matronics Email Lists
|
View previous topic :: View next topic |
Author |
Message |
nuckolls.bob(at)aeroelect Guest
|
Posted: Sun Jun 28, 2020 5:42 am Post subject: Measuring battery internal resistance |
|
|
At 10:29 PM 6/27/2020, you wrote:
Quote: | --> AeroElectric-List message posted by: Dick Tasker <dick(at)thetaskerfamily.com>
Oops. For your example, the delta current is actually 2.444-1.235=1.209A. So the R=0.015/1.209=12.4 milliohms.
You forgot to subtract the first reading. Other than the simple math error (something I do all the time...) the rest of the explanation is spot on.
Dick Tasker
|
Good catch! Thank you sir.
BTW . . . I've been playing with my
newly acquired CBA IV battery analyzer
from West Mountain Radio.
I've confirmed suspicions that not
all 18650 cells are what they're 'marked
up' to be.
A few utility cells in the stable
are marked with truing amazing
capacity values like 3800 and 9000 mAh!
While doing cap checks on the cells I'm
noticing some common traits in LiFePO4
cells that contribute to and article/white
paper on system integration of lithium
onto our airplanes.
I do have a couple of cells by Panasonic
that were advertised as 2900 mAh devices.
They are proving to perform as advertised.
Just for grins, I conducted a quick
delta-I resistance check on one of the
cells last night. Snapshot attached.
The CBA IV software has a 'dynamic'
current mode that allows you to change the
load current while the test is running.
Pretty cool . . .
I've got brand new Aerovoltz and Hawker
batteries ordered on which I'll conduct
and record a library of performance curves
for comparison in the white paper.
Bob . . .
| - The Matronics AeroElectric-List Email Forum - | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?AeroElectric-List |
|
Description: |
|
Filesize: |
49.86 KB |
Viewed: |
1918 Time(s) |
|
|
|
Back to top |
|
|
nuckolls.bob(at)aeroelect Guest
|
Posted: Sun Jun 28, 2020 2:06 pm Post subject: Measuring battery internal resistance |
|
|
At 03:58 PM 6/28/2020, you wrote:
Quote: | Thanks Bob and Dick for the details of measuring IR....
I will pursue a simple test setup....
Dave |
What are the highest and lowest voltage battery
packs you want to test?
Bob . . .
| - The Matronics AeroElectric-List Email Forum - | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?AeroElectric-List |
|
|
|
Back to top |
|
|
|
|
You cannot post new topics in this forum You cannot reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot vote in polls in this forum You cannot attach files in this forum You can download files in this forum
|
Powered by phpBB © 2001, 2005 phpBB Group
|