There are multiple types of cheating that can be done:
- high current original cells of lower capacity (seen plenty of Samsung 13Q in 1.5/3Ah packs), which is the best fake option you can get
- low current cells in power tool batteries; battery will work fine at low power use like with a...
Some of my latest:
3x18650 for string LED emergency lights. Sting on the upper side of the door of each room. In case of power outage. the 12V LED string can be turned on independently of anything.
3x18650 for old army 12V walkie-talkies. These are really good, was worth to convert them...
If you test capacity when charging, the test is useless, it can vary a lot depending on the quality, state of the cell, temperature, many other things.
Your tester should fully charge, then test on discharge to measure capacity. That value is then relevant with little other influence.
Yes, the higher the current, the lower the sustainable capacity will be. Even Samsung cheats on this for cells, they give the mAh rating at low current which differs significantly from the capacity at high drain (max cell specs).
For old cells, ~500mAh is kindof a standard but they usually can...
If it's a rebrand it does not mean it is a bad cell.
I've seen plenty of LG C4 rebranded as HE. 2800mAh instead of 3000 and lower discharge max current; other than that 100% LG original, but they were not HEs.
You still can't have a "T" in there.
I think they mean 2520 minimum capacity, not 520, lol. 3C discharge would imply that they are relatively recent good cells, not rebranded old junk. Price range is normal for this type of cells. I had similar 2600mAh grey for testing, they were up to declared specs.
I managed to assimilate one of these:
I can set the min V value to anything (using 15V now) and select the discharge current as long as I don't exceed the max power rating of the tester (150W).
So I can do fine and safe with tests at 6.5A...
Let's look a little at the 26650 vs 21700 situation regarding heat exchange / overheating.
Let's assume the following: we have a 26650 and a 21700 made with identical chemistry and we want to charge/discharge them.
Which one can evacuate heat better, which one will overheat faster on the same...
Useful info, now we need the experience with them.
For Li-ion cells I kind of know the proper weight for any 18650-21700-26650 so that's one of the 1st basic filters I use when dealing with an unknown cell.
For LiFePo4s I did not had fakes to see how they behave compared to originals. Hopefully...