Cell impedance of Thundersky and CHL lithium battery
The yellow cell is Thundersky, The green cell is CHL,all 40AH capacity,of course,bigger capacity always less impedance
Who else have other brand battery data,pls upload here so that we may compare each other.
have you tested CALB (formerly Sky Energy)?
0.3mOhm is very good!
how does that tester measure the internal resistance?
is it AC resistance?
or is it measuring actual voltage sag while drawing two or more different amps?
at 90% state of charge (so full charge with 4Ah removed), what does the voltage sag to at 145A?
my thundersky 2010 manufacture date cells sag to 3.04v @ 145A when only 4Ah removed (1.76mOhm DC resistance)
what physical dimensions are CHL 40Ah cells?
what is its mass?
Matt
Ok,finally we get battery from CALB (formerly Sky Energy),it is better impedance,but too difference between cells,CALB is similar to GBS impedance and better than Thundersky,I think all of them come from the same technology and dosage.
interesting there was such a wide variation in resistance in the CALB cells.
From what I understand, the manufacturing process is not precise.
The selection process is though,
which is how you can get a matched set of cells from a production process that is imprecise.
were all the CHL cells in your intial post from the same batch, or was a selection process used to match them?
I noted the variation (44.0 to 44.2Ah and 0.29mOhm to 0.31mOhm) to very small.
a variation cell to cell that small means one can get away with just measuring pack voltage halves to detect a failed cell, instead of doing a cell level BMS
What SOC are your cells shipped at? 50%?
Matt
Dear Matt:
Your are very professional, The Battery BORN and SELECTION is more important than BMS.
Normally we picked up from impedance,then capactity and then voltage....
We normally ship at 60% SOC.
Will anyone show more brand lithium battery impedance here ?
No one want to challenge our quality ?
Visitors from 6 countries and area at the same day take interesting with our advanced production machine and procedure....they are from Australia,Spain,Germany,Israel,USA and Taiwan....etc
Who has A123 LFP battery and post its impedance here ?
I have already use A123 in superbike with 32 cells! :-)
http://www.youtube.com/watch?v=ZtcqEOjbT-Q
I have the A123 20Ah cells.
Single 20Ah flat cells measures .56 to .6 milliohms
2 in parallel to get 40Ah shows 0 / Zero milliohms. (My meter only goes down to .01 )
So, we're talking microohms now...
Unfortunately, I am unable to upload these pics here. ( uploader not working ? )
So, here's the link to FalconEV lithium battery page
http://www.falconev.com/batteries.html
each cell's weight is 1 lb
so, 40Ah is 2 lbs / .91kg
What is the green cells weight ?
CHL 40ah battery is 1.5kg/cell,all chinese LFP battery are almost the same weight and specification.
I think A123 20Ah flat cells measures .56 to .6 milliohms is very good too,less capacity will naturally be more impedance.
Anybody have samples from BYD ? it is so famous,but none of us know its data and performance on market.
But BYD have Warren Buffet!!!
And you????
But BYD have Warren Buffet!!!
And you????
Let's why we are eager to know BYD good battery ! Will anyone do me a favor to show it here ?
We want know your battery, not battery from other supplier.
Please, do you have more information or not.
C-rate charge and discharge? Max/continue?
How many cycles 80%DOD at 3c discharge and 1c charge? Do you have this test....or do you want we pay for your batteries, and we make the test....don't jock
It is 6C continue discharged,we just do 1C 80% SOD,by now it is 3% drop after 500cycles,more cycle is under testing day and night.
Don't have 3C discharged data..... Sorry !
So make also this test....
and what about charge in this 500 cycles? 0,3C, 0,5C, 1c????
0.5C charging,1C discharged
Finally our website come out, www.china-huali.com
since we are focus on chinese E-bus market at the moment,so that we don't have English website,any more questions,you may contact with me directly.
here are spcification of our LFP battery !
Ok,finally we find the best LFP manufacturer,TCL from china,it is 0.15 mOhm on 40AH batteries,it is a pity that their price is 2 times than CHL
Anyone have experience with GBS battery?
On their website they claim GBS to be 10% better than Thundersky , do you feel is true ?
I will be able to tell you in around 5-6 weeks when the scooter I have ordered with CHL 50Ah batteries will arrive.
What would be the approximate cost of 12 of the CHL 40ah batts to USA?
I think it is around 800dollars to west coast and 900dollars to East coast by sea.
What would be the approximate cost of 12 of the CHL 40ah batts to USA?
Pls give us detail address including post code,we will check "door to door" cost by air for you.
33403 postal code
West Palm Beach, FL USA
Ok,we got the information from shipping company that the air freight cost of 12 cell battery from china to Miami airport is around 250dollars.
And the total cost broken down into per cell cost and shipping.
40AH is Usd50/cell,12 cell will cost 600dollars,pluse 250dollars airfreight.
Total costs is 850dollars
sorry,forget to upgrade the yellow cell
