Today I did a more methodical runtime test. I took the two flamed and two of the grey batteries and ran them down until the voltage dropped to 2.70V.
Time
Flamed 1
Flamed 2
Grey 1
Grey 2
0'
4.15V
4.23V
4.19V
4.23V
16'
3.57V
3.58V
3.68V
3.69V
22'
3.50V
3.53V
3.23V
3.35V
28'
3.43V
3.49V
2.87V
2.91V
34'
3.25V
3.43V
2.80V
2.79V
40'
2.98V
3.26V
2.75V
2.74V
46'
2.81V
2.90V
2.72V
2.71V
52'
2.75V
2.76V
2.70V
2.69V
58'
2.72V
2.71V
----
----
64'
2.70V
2.69V
----
----
Afterwards I tested the over-discharge protection by hooking the batteries up to a flashlight with a boost driver. Both types triggered. The flamed ones reset the circuit as soon as the load was disconnected, the grey ones stayed locked until they where put in the charger.
I am now doing this same test using my other L2M with a 3 mode 4.2v - 8.4v dropin and using the same (freshly charged) Trustfire Flame Protected 18650 #1 from above.
Another thing I noticed is the 4.2v - 8.4v dropin only gets warm where the 0.8v - 4.2v dropin gets HOT.
Starting voltage = 4.19v
2 hrs.
2:30
3 hrs.
3:30
4 hrs.
4:30
5 hrs.
5:30
6 hrs. and still going.....WOW!
The light is obviously dimmer but it's still going. There's got to be something wrong here. Is this even normal?
I'm going to stop at 6 hrs. and check the voltage. Voltage is 2.95v which is BAD for a Li-ion battery right? What the hell happened? Any ideas?
Thank you, thank you guys for doing these run tests. I've seen good reviews of the flamed trustfire 14500 and 18650 but it doesn't seem to much out there about the 16340. Thanks Al and others as I'll be picking up some of these flame TF in all 3 of these sizes.
I say be careful though because my undersanding is although the batteries have cut-off protection, we should not be trying to trip that protection as this could damage the battery which can lead to other scary stuff happening. I recall being cautioned on the CPF battery forums when doing run time tests on my protected li-ons and the consensus opinion was to not let your li-on batteries wun down that low.
Dont worry i am careful when it comes to liths, but no matter how much you know about these chemistry's there will always be something to learn right. When it cutoff i didnt turn on the light to drain the cell.....just took the cell out and let it equalize and then put it back on the charger.
I could have kept going but it just didn't seem right. Could it be because it was the 4.2v-8.4v dropin and just 1 - 18650? The end voltage was 2.95v which is way too low for li-ions right? I charged it up this morning and it was 4.19v.
I reckon 2.8-2.9V is the safe lower limit. And that's after letting them stand for a while to recover. The AW IMR cells say never go below 2.5V but that's under load - the voltage can sag quite a bit under load.
I could easily be wrong - but from memory, they are mostly OK down to a bit below 3V. There is very little usable power left below 3.3V but that isn't the same thing as unsafe.
I have heard that if you want to get more cycles from the batteries that you should recharge at 3.6V and that laptops do not go below that amount (I have no idea if that is true). AW says his li-ion batteries are 0% at 3.5V. I try not to go below 3.6V (at rest).
And the cycle life is vastly (1000%) increased for a 10% drop in capacity if you don't charge them above 4.1V. This is the level my charger that allows me to control such things is set to.
The down side of this is that cheap LiCo cells (most of what you can buy) will only live for a maximum of three years from the date of manufacture, not first use, anyway. Cycle life may be irrelevant in the face of this.
Dude your not the only one man.....6h on a single cell....WOW. Im just surprised how well these Flame cells are doing, for the price i was'nt actually expecting much of a runtime, but since they have done better then my AW's and SF cells what can one say really, the members on cpf are just missing a deal.
I still think it has to do with using the 4.2v-8.4v dropin and just 1 - 18650 or maybe it was a fluke one time only thing. I think tomorrow I'll try the same test but with one of my AW's and see if it goes 6 hrs. or so. Stay tuned.
