Not when it comes down to getting it bundled with a flashlight for so cheap. This is convenient for the countries that can’t get cells shipped by themselves.
To import 100pcs of 18680’s into New Zealand shipping alone costs $120+ USD, whereas it’s free shipping when in a flashlight. Even 10pcs costs $30 USD
I’ll upload my graph tomorrow.
Sofirn 26650 High Drain is only a 15A cell for max continuous discharge current. 20A was far too high. It could be that the added button top is increasing resistance thus causing higher voltage drop than without it
Very expensive shipping to New Zealand via USPS is the only option available right now. There was a cheaper option until some idiot tried to import a gun.
As you can see on the below graph that 20A is too high
There’s too much voltage drop on the 20A to be of much use. Sofirn don’t give a data sheet with a max temp so I didn’t want to risk it. 20A reached 70 degrees.
This test on the Samsung 25R shows that the 30A is too high and it’s similar to the 20A curve of the Sofirn. I’m kind of new to judging discharge curves but it looks too high.
EDIT: I don’t know why I can’t link that page but select and search via google and it’ll come up
I always though maximum discharge rates where based on temperature. Cells tend to vary in max temp with some at 70°C and some at 80°C. If it did not exceed 70, then it might be fine at 20A continous. I'm not familiar enough with discharge curves to know what's considered usable or not usable.
HKJ's links uses spaces which require the advanced post editor to post them.
Yeah, at 25A you can see it sag and then as it heats up the voltage rises back up. That and the big loss of capacity says 25A continous is not so good. I’m surprised the temperature didn’t go higher.
I know HKJ is on this forum, I wonder what he would think of these discharge curves.
I have noticed that Mooch and HKJ don’t always agree on the Continous Discharge Rate of the same cell so it makes sense that it is somewhat subjective.
I think I would say the Sofirn HD cell is not good for 25A continous due to it’s big loss of capacity and the dip and recover in voltage.
Maybe 20A CDR is more accurate, but still not quite as good as the Liitokala black or cyan 5000mah (which is 20A CDR).
It’s definitely better than the Sofirn non-HD battery, though. I don’t think anyone has done discharge tests on it like above, but it’s reduced lumens tells me they are not high current at all.
Some of that capacity would be resistance/heat though so it’s not what’s actually gone into the battery. I’ve had an Ultrafire 18650 show 7000mAh while charging lol. Chargers that measure mAh are useful but a discharge test is needed to determine exactly what the true amount is.
FWIW - I just got two Sofirn light kits with their own branded batteries. One was a 21700 and the other an 18650. First thing, I rand them through a normal test cycle in a Zanflare analyzing charger. Both tested well past100mah over their ratings.