@willie said:
There's a ton of fake lithium ion cells out there (i.e. labels saying samsung such-and-such with all the right numbers, with some crap cell inside) so I wouldn't go anywhere near amazon or ebay. There are a few vendors that are able and willing to stock authentic cells. r/batteries on reddit is a decent source of info.
Yeah it can be tricky. I wouldn't trust anything that claims over 2500mah capacity, based on buying cells that are both 2500mah and 3000mah, the 3000's had absolutely zero additional capacity. They would just get hotter while discharging, but be able to supply exactly the same amount of watts to your load.
As well, it's a case of "get what you pay for". I bought some cells that cost a bit more, 2500mah. Seemed like legit cells. Well balanced -- very very close capacity and voltages on each cell, even under heavy discharge, capacity exactly as rated. Then bought some other cells for a lot less -- sure they were "worth the money", because they were so cheap, but they are hardly living up to the advertisement. Easily 20% lower capacity, different cells having much different internal resistance, so they'll drop off dead at very different times from one another. Even then, if you have a good cell balancer and don't discharge at a huge rate, they could possibly work ok.
For my money I'd rather have the higher quality cells though.
There are youtube videos on it -- it does what it sounds like, takes power from the overcharged cells and uses it to charge the undercharged cells. Much more useful than passive balancers which simply discharge the cells that are overcharged.
Looks like that seller doesn't have the 2500mah cells anymore. Too bad, they were about the same price, and quite good. If memory serves, tested right around 2400mah real capacity.
As far as I can tell, from what I've read mostly, there are two major things to look for to determine legit cells.
1 -- Do the cells printing have "dots" in them? Labels on real samsung cells look like they've been printed on a dot matrix printer. Counterfeits rarely bother with this detail -- the label looks like normal text printing.
2 -- Is the deal too good to be true? Real cells are going to be something like 5 bucks each, maybe a bit more, not $2 - $3.
Oh, I guess also, anything claiming more than 3000 mah in that form factor is a scam.
@WSS said:
I've had worse luck with Amazon than I have eBay. Got some outright clonefrauds sent from Amazon, and they didn't even give a shit. Then I got an OBDII bluetooth reader with both pirated and malware for Android, and finally was sent a box with half of the product missing (not damaged). Fuck Amazon. At least eBay gives me a chance to get my money back if they refuse to give me what I paid for.
#fuckBezos
Yeah, the seller feedback is much less important to sellers on Amazon. On ebay, it's front and center and they encourage you to leave feedback. Crappy sellers have a hard time continuing to sell on ebay.
On amazon, on the other hand, if a seller sends a counterfeit product, it normally ends up being a negative review against the product, not the seller. Bad sellers will attach themselves to highly rated products to sell fakes. It's extremely difficult to tell whether you'll get a good product or not -- there's no way to know which sellers a positive review was given for, or negative. So for an abused listing, you see some good reviews and some bad with no indication who sold the good or bad products.
On amazon, I try to avoid buying things from third parties, unless said third party designed / manufactured the product. Just tons of garbage on amazon.
Really love this sentiment:
#x# #fuckBezos
That said, I do have to say, Amazon makes it easy to return stuff. For some items they don't bother making you send them back, they just give you the money. So they don't just fuck the customer, they also fuck the seller. Everyone gets fucked. It's a real gangbang over there.
In any case, I buy tons of stuff from both amazon and ebay, so I would say on the whole my experience has been good with both. I just want to acknowledge what people have said about counterfeits being a problem on amazon. I would say yes, that is true. I haven't been hit by it as far as I know, that I can recall, but I've held off on buying plenty of stuff because, reading through the reviews, it was clear that some of the sellers were selling garbage and there was no way to know if you'd get the real product or not.
@AnthonySmith any luck with this? Do you have some kind of setup for welding packs together? I'm wondering what you're using and am thinking of some kind of homebrew setup with a gel cell. There are some youtube vids about how to build those.
Amazon reviews and feedbacks are cooked up compared to ebay. This may be Bezos himself cooked up, use open source softwares for cloud hosting without contributing a penny to open source development.
Ebay exited Indian business. I am a sad consumer due to ebay exit, even now Amazon or other players not able to bring Electronics components like we had in ebay.
My perceptions about China got changed, they are great makers with solid engineering skill, hard work. Original / clone is how one could perceive economy, rich/poor, morale, ethics and law, god, inner voice, self esteem, hassles, life time of product, serviceability, space etc factors. Thankfully Open Source exist for software market.
Comments
Yeah it can be tricky. I wouldn't trust anything that claims over 2500mah capacity, based on buying cells that are both 2500mah and 3000mah, the 3000's had absolutely zero additional capacity. They would just get hotter while discharging, but be able to supply exactly the same amount of watts to your load.
As well, it's a case of "get what you pay for". I bought some cells that cost a bit more, 2500mah. Seemed like legit cells. Well balanced -- very very close capacity and voltages on each cell, even under heavy discharge, capacity exactly as rated. Then bought some other cells for a lot less -- sure they were "worth the money", because they were so cheap, but they are hardly living up to the advertisement. Easily 20% lower capacity, different cells having much different internal resistance, so they'll drop off dead at very different times from one another. Even then, if you have a good cell balancer and don't discharge at a huge rate, they could possibly work ok.
For my money I'd rather have the higher quality cells though.
This active cell balancer is pretty nifty: https://www.ebay.com/itm/174090326287?ViewItem=&item=174090326287
There are youtube videos on it -- it does what it sounds like, takes power from the overcharged cells and uses it to charge the undercharged cells. Much more useful than passive balancers which simply discharge the cells that are overcharged.
Cells that were "reasonably ok" but no higher capacity than 2500mah cells and just used the extra stored power to get hotter while discharging: https://www.ebay.com/itm/Samsung-30Q-INR18650-3000mAh-15A-Mod-High-Drain-Lithium-Battery-Cell-/223618131645?hash=item3410ade6bd
Looks like that seller doesn't have the 2500mah cells anymore. Too bad, they were about the same price, and quite good. If memory serves, tested right around 2400mah real capacity.
These were even worse -- clearly either used cells, or counterfeit. Maybe 2200mah real capacity, wildly differing internal resistance between cells. For the money, still an ok deal : https://www.ebay.com/itm/20pcs-18650-Li-ion-Battery-30Q-3000mAh-Flat-Top-High-Drain-Rechargeable/223460430116?ssPageName=STRK:MEBIDX:IT&_trksid=p2057872.m2749.l2649
As far as I can tell, from what I've read mostly, there are two major things to look for to determine legit cells.
1 -- Do the cells printing have "dots" in them? Labels on real samsung cells look like they've been printed on a dot matrix printer. Counterfeits rarely bother with this detail -- the label looks like normal text printing.
2 -- Is the deal too good to be true? Real cells are going to be something like 5 bucks each, maybe a bit more, not $2 - $3.
Oh, I guess also, anything claiming more than 3000 mah in that form factor is a scam.
Yeah, the seller feedback is much less important to sellers on Amazon. On ebay, it's front and center and they encourage you to leave feedback. Crappy sellers have a hard time continuing to sell on ebay.
On amazon, on the other hand, if a seller sends a counterfeit product, it normally ends up being a negative review against the product, not the seller. Bad sellers will attach themselves to highly rated products to sell fakes. It's extremely difficult to tell whether you'll get a good product or not -- there's no way to know which sellers a positive review was given for, or negative. So for an abused listing, you see some good reviews and some bad with no indication who sold the good or bad products.
On amazon, I try to avoid buying things from third parties, unless said third party designed / manufactured the product. Just tons of garbage on amazon.
Really love this sentiment:
#x# #fuckBezos
That said, I do have to say, Amazon makes it easy to return stuff. For some items they don't bother making you send them back, they just give you the money. So they don't just fuck the customer, they also fuck the seller. Everyone gets fucked. It's a real gangbang over there.
In any case, I buy tons of stuff from both amazon and ebay, so I would say on the whole my experience has been good with both. I just want to acknowledge what people have said about counterfeits being a problem on amazon. I would say yes, that is true. I haven't been hit by it as far as I know, that I can recall, but I've held off on buying plenty of stuff because, reading through the reviews, it was clear that some of the sellers were selling garbage and there was no way to know if you'd get the real product or not.
@AnthonySmith any luck with this? Do you have some kind of setup for welding packs together? I'm wondering what you're using and am thinking of some kind of homebrew setup with a gel cell. There are some youtube vids about how to build those.
Amazon reviews and feedbacks are cooked up compared to ebay. This may be Bezos himself cooked up, use open source softwares for cloud hosting without contributing a penny to open source development.
Ebay exited Indian business. I am a sad consumer due to ebay exit, even now Amazon or other players not able to bring Electronics components like we had in ebay.
My perceptions about China got changed, they are great makers with solid engineering skill, hard work. Original / clone is how one could perceive economy, rich/poor, morale, ethics and law, god, inner voice, self esteem, hassles, life time of product, serviceability, space etc factors. Thankfully Open Source exist for software market.
I know it's a repost from another place, some year back, but:
