Budget 18650's from AliExpress (fake HG2 Brown cells)

So I bought 20 18650’s from AliExpress with low expectations and knowing I could probably use them in cheap flashlights and old laptops etc.

They arrived and I tested them using a DL24P 180 watt dummy load tester

The capacities ranged from 2732mAh to 3391mAh. Quite a range to say the least.
4 were in the 2700mAh range
11 were in the 2800mAh range
1 was in the 2900mAh range
4 were in the 3000mAh range

This distribution indicated to me the batteries were hand picked before shipping to evenly distribute good and poor batteries in every order.
The capacity claims for the vast majority of my order seems to be CHARGE capacity and not discharge capacity (which is the most important)

I then tested their current handling characteristics and found that at 5Amps discharge the battery temperature rose to 46C (not bad)
At 10A it took 3 minutes to reach 45C, 4minutes 30seconds to reach 50C and 7minutes 15seconds to reach 60C at which point I stopped the test. Voltage settled at 3.6v

So I would say this is a 5 or 6Amp battery cell, but not suitable for 10A discharge rates as it would exceed 60C in 7 minutes at 10Amps
In a pack probably faster to 60C and longer to cool down.

Battery internal resistance was about 0.1ohms for the lot.
Overall I would say this was a pretty good deal. The cost with shipping for all 20 was $56.00 delivered or $2.80usd per cell.
But they are not suitable for ebike batteries or any high drain application.

The syringe is solder flux :smiley:

interesting insights. thanks for sharing.
I have seen a lot of these cells online and I was hesitant to order them.

Thanks for sharing the test results. Indeed, batteries on Ali Express are very cheap, very tempting. And I have bought quite a few of them to use in my inexpensive flashlights. For flashlights that are more expensive, I would always buy with battery included and use it, instead of risking damage from the cheaper Ali Express batteries.

Did you buy them knowing they were fake? If they are not HG2’s , what are they? How do you value something that is fake?


The bigger mystery is how you’ve completely avoided buying anything made in China !

Do tell ??

No problem.
I do have a good collection of batteries from IMRBatteries and they are certainly better.

But I’ve also dabbled with the el cheapos for about a decade now and to be honest, never had a problem with them as far as safety.
I probably have or have had several hundred non authentic / cheap cells for various projects… China is a nation of forgery and copying. I can all but guarantee something you own is a fake from China or has fake components.
It’s just a different culture.

A few of these fake HG2’s tested out over 3000mAh while most were around 2800mAh…….for less than $3 per cell….and good to about 6 or 7 amps safely.
For less important items like old laptops, less expensive flashlights and experimental purposes they are fine as long as you know their limitations.
18650 fires outside of a pack and in lower drain applications are nearly unheard of.

For critical applications I’d use the real McCoy like Samsung or Panasonic etc.