The LiFePO4 Headway cell 38120P TEST REPORT inside

[Doctorbass]

I received 3 LiFePO4 38120 cell of 3.2V 8.0Ah.

I will test those 3 identicals cells with my lab equipment soon and will post some true specs. I asked 3 for having better and realistic results acuraccy.

Here are some spec from Headway:

Oem specs
3.2V
8.0Ah
300g = 85.3Wh/kg
25.6Wh/cell
80A continuous
160 peak
2.8mohm


See the pics:


Doc

[drewjet]

This should be interesting!

Do you have a price and source for them?

[Ypedal]

woooooo.. looks nice !

Testing, testing.. 1... 2... testing !....

[fechter]

I can't think of a better person to test them.

Do you have any idea what the price on those will be?

[RLT]

Dang!
Lately, I've been working with some 32650 'old style chemistry' LiIons rated at 3.6V 5000 mAH, /2C (4.8 AH @ < @ 5A or under and .... 3.8AH @ 12A, actual, according to my CBA) , and thought the ~$12.50 (including shipping from China) I paid for them, made them the best AH per dollar deal available,.... I have 30 now, ordered another 60 of them a month ago; (Should be here next week or so.)

Wish I'd known about these. Price is competitive; safer chemistry and better high current capacity. I sure wish I had bought 60 of these instead.

Hope they turn out to be as good as they sound!

If so, I'm afraid I'm going to spend another thousand dollars on batteries.

[OneEye]

Where are these available commercially?

I assume that someone sent them to you for independent testing to verify their claims as they market them to the masses...but we couldn't find them available for purchase after the ZEVA reports on these cells came out. Maybe I'm not looking in the right places though.

[recumbent]

Nice format size, and at $18.00 per cell, nice price.
Only 1000 cycle lifespan, maybe the chemistry needs a little tweeking.
Still, the cost benefit is worth overlooking some of the negatives.

[A1234LIFE]

Hey Doc,

Any progress on the testing for these cells?

Steve

[Doctorbass]

I'm designing a 50A constant current load to add parallel to my cahrger that only disch to 5A.
when i will finished it i will begin the tests.

from now, i did a short test just for fun about capacity at 5A disch and the internal resistor.

i measured 8230mAh from a fully charged cell at 23 degree C at 5A down to 2.5V the nominal is 8Ah

Also i tested 6mohms instead of the 2.8 mohms from the nominal spec

[A1234LIFE]

Great. Thanks for the update. I have my doubts about the cells being able to handle a 10c continuous discharge, but if they could handle 5 or 6c continuous discharge that would be great. Some tests with a 50 amp load is exactly what I am interested in.

Steve

[Ypedal]

Hey Doc

When you have the time, do me a favor, put one in the oven, or heat it up to 35 celcius and do the same test for IR..

[Doctorbass]

Hey Doc

When you have the time, do me a favor, put one in the oven, or heat it up to 35 celcius and do the same test for IR..

In the oven??

Ypedal.. my oven can only stabilizt starting to 70C...

I have a vetter and secure ides.. the top of a computer CRT screen or the fan output of a pc power supply when playing to need for speed underground at 1280x1024

or maybe my Jobmate heatgun using my IR thermometer

but an oven... ischhh...!

[Doctorbass]

Also.. about the IR, i observed that it is not only the heat that affect it!

If you measure it immediatly after charging it, it will be higher then i you leave it few hour after charging and then measuring it!

To be valid and accurate, Capacity and IR need to be taken to a very close range of environmental and process parameter!!
that is actually the most difficult to acheive about my 360 Li-Mn Konion cells.... i measure around 15-20 a day at 5A disch but the temperature of my room affect the results...

Doc

[TylerDurden]

"Bonnet Dryer"

Mix cool air as needed for stable temperature over long periods.

[Ypedal]

Geeeeez... you sarcastic bunch....

Sunny window, heating pad, your crt monitor, sit on it for a while and incubate lol..