Shop our Airplanes Products Drone Products Sales
Thread Tools
Old Oct 18, 2012, 02:07 PM
Aviefly is offline
Find More Posts by Aviefly
Registered User
Aviefly's Avatar
Quote:
Originally Posted by ggcrandall1 View Post
Member Name ggcrandall1
Lipoly Mfr & Model Gens Ace 4S 4300 30C
Capacity 5300
C rating 30
Age (months) 1
Cycles 1
Cell IR 1.8
Temp 72.5
Equipment PL6
FOM 1.9
Max Cont. A 129
True C 24
quoted from the database thread.

Do you have some numbers mixed up somehow? you list the battery as a 4300 but then say its a 5300.
Even then with a cell IR of 1.8 the 4300 would come out at FOM1.55 , MaxA120 and a true 28C
At 5300 it would be FOM1.26, MaxA133 and a true 25C.
Sign up now
to remove ads between posts
Old Oct 18, 2012, 02:37 PM
ggcrandall1 is offline
Find More Posts by ggcrandall1
Registered User
ggcrandall1's Avatar
Quote:
Originally Posted by Aviefly View Post
quoted from the database thread.

Do you have some numbers mixed up somehow? you list the battery as a 4300 but then say its a 5300.
Even then with a cell IR of 1.8 the 4300 would come out at FOM1.55 , MaxA120 and a true 28C
At 5300 it would be FOM1.26, MaxA133 and a true 25C.
Typo.

5300mah
1.9 mohm
FOM = 1.19
Max current = 129
True C = 21

Glen
Old Oct 19, 2012, 01:14 AM
ParkJeff is offline
Find More Posts by ParkJeff
Birds do it, bees do it
ParkJeff's Avatar
Just a quick question. How sensitive are IR measurements to temperature? I've noticed some of the measurements in the database are done at temps ranging from 70f to 75f. Is there a large distortion comparing the True C of a battery measured at 70f to another at 75f?
Old Oct 19, 2012, 01:29 AM
mrforsyth is online now
Find More Posts by mrforsyth
Registered User
Lipoly performance is definitely temperature dependent. Any modelers who fly in the winter or cooler climates can certainly attest to this fact. It's for this reason that I specifically requested in post #2 of the data thread that measurements be taken within 2 degrees of 72F (or within 1 degree of 22C). Within this narrow range, internal resistance does not vary much but I still requested that the temperature be noted so that the posted data would be of most value to the reader.

Mark
RCG Plus Member
Old Oct 19, 2012, 06:41 PM
gulio is offline
Find More Posts by gulio
That's a funny word
nice diagrams in post 2 and 3.
Old Oct 20, 2012, 06:20 PM
gulio is offline
Find More Posts by gulio
That's a funny word
When looking for "cell damage,degradation,increased IR" is it more likely that it will show up at higher temps or lower temps? How about high voltage or low voltage? I'm reading mine with i-charger so I read only 1mv increments.

I 'think" I know the answer should be at the lowest temp and voltage since the IR is going to read the highest under those conditions.
Old Oct 20, 2012, 09:05 PM
mrforsyth is online now
Find More Posts by mrforsyth
Registered User
It's generally easiest to track performance over time by being as absolutely consistent as possible with respect to measurement temperature. Charge state does not matter much at all as long as the pack has had the opportunity to stabilize. I typically measure at storage voltage (3.8-3.9 volt/cell) as I do not like to leave my packs at full charge any longer than necessary.

Fortunately, my living room is typically with 1-2 degrees of 72 F so maintaining a consistent test temperature is easy for me.

If your packs are truly degrading, the 1mOhm resolution of your iCharger will be more than sufficient to tell you this, unless your packs are huge (>5000mAh).

Mark
RCG Plus Member
Old Oct 25, 2012, 09:03 AM
sailr is offline
Find More Posts by sailr
Registered User
I have been spot checking my HAIYIN packs IR during charging. So far, NONE has exceeded 1.0! When compared with my hyperions and various Hobbyking packs, the HAIYINs are MUCH lower in internal resistance. Just one more reason I have totally switched to HAIYIN for all new pack purchases.
Old Oct 25, 2012, 09:42 AM
JohnathanSwift is offline
Find More Posts by JohnathanSwift
Suspended Account
Where do you buy them?
Old Oct 25, 2012, 12:27 PM
sailr is offline
Find More Posts by sailr
Registered User
Quote:
Originally Posted by JohnathanSwift View Post
Where do you buy them?
www.haiyinstore.com

Be sure to select USA Warehouse if you are in the US or European Warehouse if you are in Europe. Other countries can use HONG KONG Warehouse.
Old Oct 25, 2012, 05:49 PM
H2SO4 is offline
Find More Posts by H2SO4
christian theme park operator
H2SO4's Avatar
Quote:
Originally Posted by sailr View Post
I have been spot checking my HAIYIN packs IR during charging. So far, NONE has exceeded 1.0! When compared with my hyperions and various Hobbyking packs, the HAIYINs are MUCH lower in internal resistance. Just one more reason I have totally switched to HAIYIN for all new pack purchases.
Sounds very committed.

Out of curiosity, what's the capacity of these cells with a <1mOhm IR?
Old Oct 26, 2012, 09:03 AM
sailr is offline
Find More Posts by sailr
Registered User
4S 5000 30C and 40C packs, 4S 2650 packs, and 6S 5000 packs.


Quote:
Originally Posted by H2SO4 View Post
Sounds very committed.

Out of curiosity, what's the capacity of these cells with a <1mOhm IR?
Old Oct 26, 2012, 09:14 AM
H2SO4 is offline
Find More Posts by H2SO4
christian theme park operator
H2SO4's Avatar
Quote:
Originally Posted by sailr View Post
4S 5000 30C and 40C packs, 4S 2650 packs, and 6S 5000 packs.
Even the 2650mAh cells boast IR less than 1 milliohm?
Old Oct 26, 2012, 09:26 AM
sailr is offline
Find More Posts by sailr
Registered User
Yes, the 2650's I have checked were below or right at 1.0 mOhm
Old Oct 26, 2012, 10:04 AM
H2SO4 is offline
Find More Posts by H2SO4
christian theme park operator
H2SO4's Avatar
Quote:
Originally Posted by sailr View Post
Yes, the 2650's I have checked were below or right at 1.0 mOhm
That would give them a FOM of 4.53, a max current rating of 126A, and a 48 'true' C. A record, I believe.

What are you using to measure IR?


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
New Product Cell Internal Resistance Meter - more useful than 'C' ratings - Now available. Inflexo Batteries and Chargers 468 Oct 05, 2012 11:02 PM
Discussion Lipo C-ratings puzzle: what's most important, C-rating or mAh capacity?? Merlin45 Batteries and Chargers 18 Apr 03, 2010 05:45 PM
Idea Proposal for simple lipo performance figures of merit kgfly Batteries and Chargers 8 Oct 29, 2009 06:55 PM
Question What is the formula for lipo discharge amps? C ratings and such? skid_68 Batteries and Chargers 6 Nov 10, 2005 09:10 AM
LiPo "C" Ratings: Useful? RD Blakeslee Batteries and Chargers 121 Mar 17, 2005 11:02 PM