9900 mAh 18650 accumulator - Page 1
Forum section: electronics / general

author: FrankBuss
author_rank: Unknown
timestamp: October 02, 2019, 10:23:08 pm
content: I bought this accu, ebay seller "toptrade2u":I charged it with 0.5 A to 4.2 V, then tested it in my electronic load in constant current mode with 0.5 A, and with a turn off limit at 3 V. Result: 400 mAh.I asked for a refund, no answer so far.Should I open one? Weight is very light, I guess there is just a small coin cell in it.

author: IanB
author_rank: Super Contributor
timestamp: October 02, 2019, 10:26:38 pm
content: I'm curious, why did you buy an "impossible" product, when 18650 cells are typically 2500 to 3000 mAh?

author: IanB
author_rank: Super Contributor
timestamp: October 02, 2019, 10:28:25 pm
content: I think you paid too much for them:https://www.ebay.com/p/925695650?iid=123738605274

author: FrankBuss
author_rank: Unknown
timestamp: October 02, 2019, 10:36:26 pm
content: Maybe there was a technological breakthrough I didn't notice, and I'm sure I get the money back, so free batteries for at least some low power applications

author: FrankBuss
author_rank: Unknown
timestamp: October 02, 2019, 10:37:41 pm
content: Quote from: IanB on October 02, 2019, 10:28:25 pmThanks, I think I should buy them, too. Worth the trouble to give a negative rating so that others don't get fooled.

author: SparkyFX
author_rank: Frequent Contributor
timestamp: October 02, 2019, 11:05:18 pm
content: Out of curiosity: How much weight per cell?

author: FrankBuss
author_rank: Unknown
timestamp: October 02, 2019, 11:26:45 pm
content: 14g. Looks like genuine Sony CT6, with 3000 mAh, should weigh 45g. There is even a seller who claims 12,000 mAh:http://cgi.ebay.de/371837870210I just bought itI discharged one of the 9900 mAh accus completely and opened it. Looks like most of it is air:

author: SparkyFX
author_rank: Frequent Contributor
timestamp: October 03, 2019, 01:11:03 am
content: With brand names like "ever fire" and "Rakieta" (sounds a bit like rocket)... my trust is very limited :-)But it reminds me to finally acquire an electronic load, i figure the amount of broken battery packs for e-bikes, e-scooters and so on will either require some refurbishing or at least cheap sources for good batteries. Might need to build a spot welder too...

author: maginnovision
author_rank: Super Contributor
timestamp: October 03, 2019, 01:38:13 am
content: I think they looked at these(similar) on keysights YouTube.

author: metrologist
author_rank: Super Contributor
timestamp: October 03, 2019, 02:51:01 am
content: Here's ya an anecdote. I bought some just like these a couple years ago, plain yellow branded GTF, 9800mAh. I wasn't expecting that, but hoped for something reasonable. I don't have a good means of measuring capacity, but two of them weigh 80g. They power a 12000 lumen, 7 led, 4 cell flashlight for as long as I've needed to use it, like over 2-3 night camping trips, and they're holding a charge a year later, as long as I insert a battery connection block.https://www.ebay.com/itm/4-3-7V-GTF-18650-9800mAh-Li-ion-Rechargeable-Battery-For-LED-Flashlight-Torch/132466001287?epid=16008260272&hash=item1ed796c587:g:KBYAAOSw-4BXYfqHhttps://www.ebay.com/itm/SKYRAY-12000LM-3-Modes-7-x-XM-L-T6-LEDs-Flashlight-Tactical-Lamp-Waterproof/331811563457?hash=item4d4182a7c1:g:xw4AAOSwax5Yx5aZ

author: amyk
author_rank: Super Contributor
timestamp: October 03, 2019, 03:19:38 am
content: Real cells, fake capacities. 400mAh is a normal capacity of cells designed for solar garden lights.

author: Circlotron
author_rank: Super Contributor
timestamp: October 03, 2019, 03:22:24 am
content: They are probably meant for powering things like this 10,000 watt PMPO speaker...https://www.ebay.com.au/itm/SMATE-5-1-CH-Dolby-Patented-All-in-one-Soundbar-Massive-150W-10000W-PMPO-HDMI/263119658198?hash=item3d43275cd6:g:g8sAAOSwTQhZgUkA&frcectupt=true

author: FrankBuss
author_rank: Unknown
timestamp: October 03, 2019, 05:00:32 am
content: Ok, the fun starts. The seller answered and wants more photos. I sent him the first photo again and described in detail what I did. Maybe I should offer to make a Youtube video, with his shop name and product listing in the intro?

author: GeorgeOfTheJungle
author_rank: Super Contributor
timestamp: October 03, 2019, 05:49:01 am
content: Wow, good stuff!

author: FrankBuss
author_rank: Unknown
timestamp: October 03, 2019, 06:17:42 am
content: Quote from: metrologist on October 03, 2019, 02:51:01 amMight be a good battery, more than twice as heavy as my batteries.For a rough capacity estimation you could try it with a resistor, for example 10 ohm (needs to be a 2 W type, use multiple in series and parallel, or a higher value, which then needs longer). If the capacity is not that high, this will drain it in a few hours max, so keep an eye on it that you don't deep discharge it and stop discharging it when it reaches 3 V, this should be safe for most 18650 accus. Then use the middle of the discharge curve, 3.7 V might be a good approximation. I guess this is what the "rated" voltage means on the battery. This means it delivers on average 3.7 V * 0.37 A = 1.4 W. If it can do this for one hour, the energy stored in the battery is 1.4 Wh. If only for half an hour, then 0.7 Wh etc. You get the non-SI value "mAh", if you divide the energy by the rated voltage, so 0.7 Wh / 3.7 V = 0.19 Ah = 190 mAh. There is even a webpage for it:https://milliamps-watts.appspot.comOr measure the current your flashlight needs and measure the time until it is dim. But could be tricky, if it uses a switched-mode power supply.BTW, I just verified my electronic load with a power supply, and it uses always 1 V as the rated voltage for battery capacity measurement. Misunderstandings like this happens, when you use silly units like AH. Couldn't find anything in the manual how to change it. So the reading "0.4 AH" means the battery really has 0.4 * 3.7 = 1480 mAh (or maybe a bit less, if the average voltage is lower), because it assumed 1 V, and not 400 mAh as the display suggested. Still about 7 times less than what was sold.So a recommendation: don't buy the RK8511 electronic load. The capacity measurement is useless, unless I missed something how to change the unit, because it should really measure Wh. I verified it with a power supply to be sure: it shows the same value, 0.0168 AH, when using 9.93 V with 1 A for a minute, and 4.939 V with 1 A for a minute, it just ignores the input voltage, and the entered cut-off voltage. Useless. I guess this is why the seller got suspicious, it can't bethatbad

author: FrankBuss
author_rank: Unknown
timestamp: October 03, 2019, 09:12:44 am
content: Ok, I think I was wrong with my conclusion that the battery has 1480 mAh and not only 400 mAh. As I tested, my electronic load shows the same mAh value for different voltages, if current and time is the same, because it integrates just current over time. This means the accu has really only 400 mAh capacity. Would be still nice if the electronic load could measure the real energy and not just this mAh approximation.

author: Kilrah
author_rank: Unknown
timestamp: October 03, 2019, 09:15:37 am
content: Well since the cells are rated in mAh then the mAh count is what you want to dispute the claims.But yeah having Wh as well is more flexible.

author: FrankBuss
author_rank: Unknown
timestamp: October 03, 2019, 09:30:08 am
content: Quote from: Kilrah on October 03, 2019, 09:15:37 amThat's right, but it is not very accurate. They would need to specify the cut-off voltage. But below 3V is not much charge left anyway, so I guess it should be within +/-10% of the mAh printed on the cell, no matter if the manufacturer deep discharges it to get a value as high as possible, or uses a slightly higher value than 3V.I will setup the serial port interface when I have some time, then I can read the voltages with a script and draw a nice discharge curve. And with the raw voltage values it is easy to integrate it for the real energy, because the current is constant.

author: IanB
author_rank: Super Contributor
timestamp: October 03, 2019, 01:35:04 pm
content: Quote from: FrankBuss on October 03, 2019, 06:17:42 amI have often done discharge tests with a resistor. If you log the voltage during the discharge you can plot a graph of voltage against time, and thus current against time (you know the resistance). Then you can find the area under the graph to get the capacity. For improved accuracy I measure the resistor value under warm discharge conditions.

author: wraper
author_rank: Unknown
timestamp: October 03, 2019, 01:42:10 pm
content: Stupid deal, for such price you can buy genuine 3350 mAh panasonic ncr18650b.

author: Bud
author_rank: Super Contributor
timestamp: October 03, 2019, 02:15:29 pm
content: @FrankBuss you are a valued and experienced person. How could you possibly fall to 9900 mA/h trap. Technological breakthroughs do not originate in China. Unless you just having educated fun.

author: SiliconWizard
author_rank: Super Contributor
timestamp: October 03, 2019, 07:54:46 pm
content: Ahah! Sure 9900mAh was next to impossible... but... 400mAh for 18650 Li-ion batteries? You bet they are almost just air!!

author: FrankBuss
author_rank: Unknown
timestamp: October 03, 2019, 08:30:35 pm
content: Quote from: Bud on October 03, 2019, 02:15:29 pmYou can never be sure. It could have been some new advanced graphene nano particle accuBut to be serious, China catches up quickly in technology. They were the first who landed on the dark side of the moon. And they plan to be the world leader in AI research. And I think they are already world leader in facial recognition, surveillance technology etc., probably "better" than NSA.

author: PlainName
author_rank: Super Contributor
timestamp: October 03, 2019, 09:04:29 pm
content: For a battery load tester, you can do a lot worse than an EBD-M05:eBay auction: #283107190979

author: Circlotron
author_rank: Super Contributor
timestamp: October 03, 2019, 09:51:28 pm
content: Quote from: FrankBuss on October 03, 2019, 08:30:35 pmWorld leaders in fashion too.https://www.google.com/search?q=china+accordion+pants&prmd=isvn&source=lnms&tbm=isch&sa=X&ved=2ahUKEwiBqoD0iIHlAhV-7XMBHadZDYAQ_AUoAXoECA0QAQ&biw=1024&bih=675#imgrc=OMEwIvEdapmSZM

author: james_s
author_rank: Super Contributor
timestamp: October 03, 2019, 09:58:12 pm
content: Just put in a claim with ebay, product not as described, forget even dealing with the seller directly. They are selling such obviously fraudulent products that there is no reason go out of your way to resolve things with them before taking official action.Even 3,000 mAh is pushing it for 18650, anything more than that I would automatically assume is fraud.

author: SparkyFX
author_rank: Frequent Contributor
timestamp: October 03, 2019, 10:42:32 pm
content: Graphene nano blockchain technology for the win!I don´t get why mAh should not be an SI-Unit. An Ampere is, an Hour is (3600 SI-seconds).Of course it is now debatable what the Li-Ion nominal voltage or the cut off should be assumed to be, although somewhat defined by the chemistry. Next is discharge rate and so on.It is generally accepted that they degrade with charge cycles, so how many would be acceptable..., i guess trade wise it runs down to how many parameters the seller/manufacturer specifies for his product.Consumer protection might argue that as the compatible equipment and the rest of the market measures in a certain way, everyone offering on the market needs to adhere to that (and is generally advised good to do so) but it is questionable if this survives international trade and definitions in trade agreements.The sellers biggest fear however is a bad rating...

author: wraper
author_rank: Unknown
timestamp: October 03, 2019, 11:22:18 pm
content: Quote from: SparkyFX on October 03, 2019, 10:42:32 pmAh is a vague figure. Does not represent actual energy for which there is watt-hour and Joule (SI). Wh is actually way more meaningful for larger batteries such as 18650 which usually are powering some sort of DC/DC converter. As they draw constant power from an input, not constant current assuming load remains the same while input voltage changes (like when battery discharges).

author: metrologist
author_rank: Super Contributor
timestamp: October 04, 2019, 12:48:14 am
content: Quote from: wraper on October 03, 2019, 11:22:18 pmI lost track of this whenhttps://www.bipm.org/en/measurement-units/

author: FrankBuss
author_rank: Unknown
timestamp: October 04, 2019, 01:06:31 am
content: Probably Ah is not a SI unit, because there is already a SI unit which measures this: 1 Ah = 3600 C (coulombs). So it doesn't make sense to use Ah for it. Of course, using "C" would be confusing for accus, because there is already a "C" rating whichmeans something totally different. I guess marketing is responsible for all this mess, they don't know much about physics or SI units.BTW, someone tested a lot of 18650 accus:http://danyk.cz/test18650_en.htmlThere are a few with the label "GIF", but in different colors than my version. He measured about 550 mAh for them. So I'm sure now I did measure it right.

author: FrankBuss
author_rank: Unknown
timestamp: October 04, 2019, 05:32:58 am
content: I left a negative feedback for the seller. This accelerated the process a bitHe offered me to refund half of the price. Of course I refused and answered that we can wait until eBay solves his scam auction.

author: OwO
author_rank: Super Contributor
timestamp: October 04, 2019, 06:41:48 am
content: taobao > aliexpress > ebay.If you search "18650" on taobao you will see all the inflated capacity listing are now gone. I dug for awhile and only found this:https://item.taobao.com/item.htm?id=545253068656&ali_refid=a3_420434_1006:1103697496:N:3FBOsCTSfhb8q8nVEGLCiw%3D%3D:b316254cfe23009afb537ce87e2a8b9f&ali_trackid=1_b316254cfe23009afb537ce87e2a8b9f&spm=a230r.1.1957635.65In the description it even says "printed 4800mAh, actual capacity 1200mAh". I think there's been some crackdowns and taobao is now much stricter on items being as described. I've bought 18650s on taobao and so far all passed capacity tests.Unfortunately aliexpress is still riddled with fake lithium battery listings.If you have access to taobao and want the best bang for buck 18650 cells, search "特斯拉 18650" ("tesla 18650"). These are around 3000mAh and cost 13yen ($2 USD), and have very similar characteristics to the NCR18650B.

author: FrankBuss
author_rank: Unknown
timestamp: October 04, 2019, 06:50:00 am
content: Thanks, but buying from Taobao is expensive for me because of the extra handling fees from yoybuy. But I reported the auction on eBay now as well as fraud. Unfortunately couldn't add any description to the report, and couldn't find any contact to eBay where a human is on the other side, so difficult report all these cases. And I bought a few others from eBay, some looks legit with reasonable ratings. Will report here again which one are good and which are scams.

author: OwO
author_rank: Super Contributor
timestamp: October 04, 2019, 06:57:53 am
content: I think there are real NCR18650B listings on aliexpress, but you have to be careful and be sure to read the 1 star reviews first. I once bought some NCR18650Bs from aliexpress when I lived abroad, and the capacity mostly checked out (measured between 3100 - 3200mAh). I would not bother trying the no-brand or "XXXX-fire" branded cells. Those are guaranteed to be mislabeled (taobao listings of *fire cells all state real capacity is not labeled capacity).

author: SiliconWizard
author_rank: Super Contributor
timestamp: October 04, 2019, 03:17:21 pm
content: Again, note here that it's not just outrageous mislabelling here, which would be bad enough.The batteries are not EVEN close to regular 18650 Li-ion batteries, their construction is pure shit. This is double rip-off. Unbelievable.So even if they had been labelled more conservatively with a 3000mAh figure or so, which would have been average for this battery format, this would still have been complete rip-off.

author: amyk
author_rank: Super Contributor
timestamp: October 04, 2019, 10:12:44 pm
content: Quote from: FrankBuss on October 04, 2019, 01:06:31 amInteresting that the no-name "bland" cells seem to be far more honest in their ratings and a surprisingly good value; the completely unbranded 2000mAh one for $1.50 was actually 2391mAh(!), almost 20% more than advertised.Quote from: SiliconWizard on October 04, 2019, 03:17:21 pmLike I said above, these are relabeled 400-600mAh 18650s. They are intended to be ultra-cheap cells for solar garden light applications, where a higher capacity would be useless.

author: IanB
author_rank: Super Contributor
timestamp: October 04, 2019, 11:09:21 pm
content: Quote from: amyk on October 04, 2019, 10:12:44 pmUnfortunately they also seem to be treated as a disposable item--I saw that some garden lights try to charge them with a direct current loop from the solar cell without any charge control or high voltage cut-off. While this worked fine for nicads it is not so fine for lithium cells and the cells tend to die after a year. Here higher capacity might even be better as there is less chance of the cells being overcharged before sunset.

author: SiliconWizard
author_rank: Super Contributor
timestamp: October 04, 2019, 11:52:09 pm
content: Quote from: amyk on October 04, 2019, 10:12:44 pmAlright; but whether they are "genuinely" intended for garden lights, that doesn't make them any less crappy probably. (I don't really see the point of using such a format for such a low capacity anyway, but that's beyond the point...) And getting the idea of selling them as ultra high capacity batteries is just ridiculous.Relabeled batteries with a x2 - x3 inflated figure is bad enough, but more common. Here we have an almost 25x factor. That's just unbelievable.Of course, as others have said, anyone actually believing that the displayed capacity could even be possible, can only be angry against themselves here I guess. But my point was that they still could have expected a typical capacity for this format, instead of the lowest cheap stuff you could imagine. But moral is, never even underestimate the "capacity" (as opposed to that of the batteries) of those sellers to make fun of you!

author: ledtester
author_rank: Super Contributor
timestamp: October 05, 2019, 12:27:02 am
content: Quote from: dunkemhigh on October 03, 2019, 09:04:29 pmOne I can recommend:https://www.banggood.com/Original-ZHIYU-60W-110W-9_99A-30V-Constant-Current-Electronic-Load-Aging-Battery-Capacity-Tester-p-1146280.html?rmmds=search&ID=529811&cur_warehouse=CN60W version for $20, 110W for $25.You can find the same items on ebay for a few dollars less, but you probably won't get the same customer service. Banggood sent out a replacement unit when something I bought arrived DOA, and then refunded my money when the replacement was also defective.

author: PlainName
author_rank: Super Contributor
timestamp: October 05, 2019, 06:20:07 am
content: Good to hear that Bangood have decent customer service (even though they do £==$ pricing conversion). I fortunately haven't had to take advantage yet, but I'm sure the time will come...

author: kjr18
author_rank: Regular Contributor
timestamp: October 05, 2019, 06:43:40 am
content: Quote from: SparkyFX on October 03, 2019, 01:11:03 amFunny thing, "Rakieta" literally means rocket in polish, so not really sounds a bit like, rather it's the same.Well, if you need genuine Panasonic 18650 cells, ebay or AliExpress are not places where you should look for them. One time when I was just looking at "more to love" on AliExpress app's homepage I found this seller that sells battery wraps and many other things for making battery packs. What's wrong with selling battery wraps, you might ask? Well, it's fine unlessthey look just like that

author: OwO
author_rank: Super Contributor
timestamp: October 05, 2019, 06:57:09 am
content: I'm not aware of any Chinese manufacturers of 18650s that reach 3000mAh, so if they show >= 3000mAh on the tester then it's most likely the tesla cells or NOS panasonic cells. Both are based on the same construction and have the same charge/discharge curve.

author: FrankBuss
author_rank: Unknown
timestamp: October 05, 2019, 03:00:27 pm
content: I dug out my GPIB adapter for my Fluka 8842A and updated mylogging script, which I developed for theRasbperry Pi logging project for voltnuts. I managed to install the script now on my main desktop PC, which is running most of the time anyway, so no need for the Raspberry Pi anymore. Then I discharged it again with 0.1 A and logged the voltage every 10 seconds:It bounces back a bit at the end when the load is turned off at about 2.9 V, but doesn't get higher than 3.2 V. But now the capacity is a bit higher with 549 mAh, nearly exactly the same as the other guy measured for the GIF brand. I guess he used the same low discharge current, because when discharging with 0.5 A, then the capacity is not as high as with 0.1 A, which is expected.Hereis the Google sheet for all the logged data, all formulas, and the diagram.I got the Rakieta batteries as well (fast shipping because shop in Germany). Will test it now.

author: metrologist
author_rank: Super Contributor
timestamp: October 05, 2019, 08:39:32 pm
content: Expect the marketers to use your chart to express battery life in hoursCan't wait for the next install...

author: FrankBuss
author_rank: Unknown
timestamp: October 06, 2019, 11:44:26 am
content: The "RAKIETA" measurement is done. As expected, not 12000 mAh, but at least a bit better than the garbage GIF battery: 1502 mAh:Looks like the material is different, because the curve looks different and lower voltage.Refund request sent.

author: SiliconWizard
author_rank: Super Contributor
timestamp: October 06, 2019, 02:56:03 pm
content: The curve is interesting. For a typical Li-ion battery, especially at this relatively low discharge current vs. capacity, I would expect a somewhat steeper initial decrease and then a bit more flat once voltage has reached 3.6-3.7V. It's almost linear from 4.1V down to 3.4V. Weird.

author: FrankBuss
author_rank: Unknown
timestamp: October 06, 2019, 07:40:03 pm
content: Quote from: SiliconWizard on October 06, 2019, 02:56:03 pmI guess if they lie about the capacity, they might not use the best materials either, which could lead to strange curves. Or maybe it is an old refurbished laptop cell. Sometimes they even claim that they have overcurrent etc. protection, but some Youtube reviews show that they don't have it.Now the question is, how could this be stopped? Obviously eBay doesn't care, they just refund the money with buyer protection and the shop continues to sell them. Maybe if everyone who could measure the capacity would buy one, then claim a refund and leave a negative feedback, would stop these shopsThere are cheap battery capacity tester for like $20 on eBay as well.

author: SiliconWizard
author_rank: Super Contributor
timestamp: October 06, 2019, 10:26:28 pm
content: Quote from: FrankBuss on October 06, 2019, 07:40:03 pmThis could typically be explained if they used coke as an anode material (instead of graphite), which is pretty cheap and was used in earlier Li-ion batteries.And yes, it's quite common that those crap batteries don't have ANY embedded active protection.

author: IanB
author_rank: Super Contributor
timestamp: October 07, 2019, 01:36:32 am
content: Quote from: SiliconWizard on October 06, 2019, 02:56:03 pmIf I compare with discharge curves published by Panasonic, Sanyo, Sony etc. it doesn't seem all that strange. In fact, it looks quite typical to me.

author: FrankBuss
author_rank: Unknown
timestamp: October 07, 2019, 03:19:10 am
content: The drama continues. Message from today from the seller of the 9900 mAh GIF accumulator with the 500 mAh capacity:QuoteSo probably this is the reason why there is no negative feedback with the battery capacity as the reason. My answer:Quote

author: OwO
author_rank: Super Contributor
timestamp: October 07, 2019, 03:26:58 am
content: Quote from: FrankBuss on October 06, 2019, 07:40:03 pmWhy not just not buy from ebay anymore? I see everyone on this forum complaining about shit from ebay yet they still keep buying the crap. I've bought things from ebay, banggood, and aliexpress before and the only place I ever got good (based on discharge capacity test) 18650 cells was from aliexpress. Of course if you want absolute assurance you probably want to buy from nkon.nl (since you are in EU) or similar.

author: FrankBuss
author_rank: Unknown
timestamp: October 07, 2019, 03:38:59 am
content: Right, and I'm already doing this. I bought a few things from Aliexpress and so far no problems.But eBay has a wider choice of articles. And most of the time it is no problem. For example my Arduino Nano clones I bought from eBay are working without problems, or other standard products like the ESP32-wroom, or SMD to DIP adapter boards. But maybe better next time to search on Aliexpress first for everything.

author: BravoV
author_rank: Super Contributor
timestamp: October 07, 2019, 03:40:19 am
content: Quote from: OwO on October 07, 2019, 03:26:58 amMeh .. just freebie junkies, and sad part is , I believe most are knowledgeable enough to be aware, that those mostly are fishy deal, and yet, they're just hiding behind the dispute and refund mechanism, and keep the merchandise for free.Plain greedy, that is all about, nothing to see here, move along.

author: FrankBuss
author_rank: Unknown
timestamp: October 07, 2019, 03:48:02 am
content: The greedy persons are the sellers. Probably I wouldn't have complained if I would have gotten a reasonably good accumulator, knowing that sellers sometimes exaggerate a bit. But I really didn't expect to get garbage. There would be no problems, if the sellers were honest and would sell only good products, for a fair price.But I agree that it can be a problem, if the buyers expect too low prices and don't want to pay fair prices for good products.

author: BravoV
author_rank: Super Contributor
timestamp: October 07, 2019, 03:55:41 am
content: Quote from: FrankBuss on October 07, 2019, 03:48:02 amWell, with your 2000+ posts count, clearly you're not a noob in electronics. Keep arguing & pretending you're purely 100% innocent is just showing your true attitude, greedy.Anyway, next time if I found a deal of cheap <$5 of 18650 battery, that claimed to have 121GigaAhat eBay/Aliexpress or any online deal, that have a robust dispute/claim mechanism to protect buyer, surely I will pm you 1st.

author: FrankBuss
author_rank: Unknown
timestamp: October 07, 2019, 02:04:59 pm
content: I got another battery, and finally this was a good one.Hereis the auction, "Sony Li-Ionen Akku | US 18650 VTC6 | 3,7V 3100mAh 30A". I couldn't find an official datasheet for it, buthereis a presentation. It can be discharged with up to 20 A! I tested it with 1 A:Auction says min capacity is 3000 mAh. Measured with 1 A discharge current was about 2900 mAh, good enough. I'm guess with 0.1 A and a cutoff voltage of 2.5 V (I used 3 V), it could be 3000 mAh. So if you need a good 18650, but without protection, I can recommend this product.

author: OwO
author_rank: Super Contributor
timestamp: October 07, 2019, 03:37:43 pm
content: Why even bother with that crap when you can get real NCR18650B for cheaper:https://eu.nkon.nl/panasonic-ncr18650b-made-in-japan.html2900mAh likely means it's new old stock or (worse) refurbished.Unless that listing has changed its price, $5 is not a cheap price for a 3000mAh cell. $2 is how much you should expect to pay for a 3000mAh cell of unknown origin (but passing capacity tests), and $5 is the point you should expect genuine panasonic cells with guarantees.

author: FrankBuss
author_rank: Unknown
timestamp: October 07, 2019, 04:42:04 pm
content: According to the diagram on page 5here, I would say it is well within spec. I used a cutoff voltage of 2.9 V and 1 A discharge current. If I would have gone down to 2 V, it would be even more than 3000 mAh, but I didn't want to stress the battery. And 2900 is less than 4% difference from 3000, good enough for me

author: thm_w
author_rank: Super Contributor
timestamp: October 07, 2019, 10:58:00 pm
content: Quote from: wraper on October 03, 2019, 01:42:10 pmQuote from: OwO on October 04, 2019, 06:57:53 amYeah I've bought a few sets of NCR18650B (2.50 to 3.50 EUR each, includes shipping cost) from aliexpress. All 10 cells measured decent capacity, 3190mAh to 3400mAh. Most of they come with protection circuitry as well, oddly at the same or less cost, which is a huge bonus for me.Those Sony cells are probably good, but more for high drain applications, not sure if its protected.Going forward this is the only cell I will use for low drain devices.Looks like my cutoff was ~2.9V:https://lygte-info.dk/review/Review%20Charger%20LiitoKala%20Lii-500%20UK.html

author: metrologist
author_rank: Super Contributor
timestamp: October 08, 2019, 01:27:14 am
content: Quote from: BravoV on October 07, 2019, 03:40:19 amYou seem to post that as an attack on the consumer, like it is their fault for trying to be frugal. Do I misunderstand? It's OK for all sellers to play a shell and pea game?

author: FrankBuss
author_rank: Unknown
timestamp: October 09, 2019, 05:31:36 am
content: Got a reply from the seller of the 12000 mAh RAKIETA accumulator, which I measured 1500 mAh. He says there is nothing wrong with it, I should have read the fine print in the auction text carefully:QuoteTranslation:QuoteI'll wait what the eBay customer service thinks about it.

author: FrankBuss
author_rank: Unknown
timestamp: October 09, 2019, 09:47:52 am
content: The first seller, toptrade2u, refunded my money fully now. He still begs me to remove the negative feedback, which of course I won't do. I told him it is his fault and he should remove the auction, which he doesn't do. So if someone wants a crappy 500 mAh battery for free, buy this one:https://www.ebay.de/itm/123765381068and then request a refund, and leave a negative feedback. Maybe someday these scammers will learn, but probably they will just create a new account if it gets too many negative feedbacks, these criminals don't change.

author: GeorgeOfTheJungle
author_rank: Super Contributor
timestamp: October 09, 2019, 10:23:24 am
content: They did nothing wrong... because "9900mAh" is the cell's "model number/name" not any thing else you might have (wrongly) imagined.

author: PlainName
author_rank: Super Contributor
timestamp: October 09, 2019, 11:49:15 am
content: Quote from: GeorgeOfTheJungle on October 09, 2019, 10:23:24 amDon't know what his auction says, but here's an English one with a slightly lesser battery (only 9800mAh!):eBay auction: #173672497359Same should apply to this, no? Take a look at the small print:QuoteSeems clear enough to me that the 'model number/name' is "18650" and the alleged capacity is 9.8Ah.

author: madires
author_rank: Super Contributor
timestamp: October 09, 2019, 01:39:01 pm
content: Quote from: FrankBuss on October 09, 2019, 05:31:36 amAs a seller located in Germany he should know the BGB. If he offers 12Ah LiIon batteries he has to deliver them. The fine print doesn't change that. Actually it even confirms that he knows that the LiIon battery doesn't provide 12Ah. So it's clearly a wilful fraud. If you like you can file a criminal complaint.

author: GeorgeOfTheJungle
author_rank: Super Contributor
timestamp: October 09, 2019, 02:02:53 pm
content: Citroen sold a car with the name 2CV that didn't have 2CV...

author: FrankBuss
author_rank: Unknown
timestamp: October 09, 2019, 03:49:06 pm
content: Quote from: madires on October 09, 2019, 01:39:01 pmWhere can I file this? But I think this might be too much trouble, law costs etc.But I thought about sending an Abmahnung (cease and desist letter). After all sometimes I sell on eBay, too, and I'm registered as a business at eBay. If he continues to sell this crap, then it might be easier with this letter to win a law suite. But would make even more sense for the bigger sellers who send good batteries. I wrote to one asking if he would do this, but no answer so far. Maybe they think the trouble is not worth it, and would be like whack-a-mole: you stop one, but at the same time another one appears. And I guess impossible or far to expensive to try this with a seller in China.

author: SparkyFX
author_rank: Frequent Contributor
timestamp: October 09, 2019, 04:06:44 pm
content: Quote from: FrankBuss on October 09, 2019, 05:31:36 amWho cares about thepower, when thecapacityis in question

author: FrankBuss
author_rank: Unknown
timestamp: October 09, 2019, 04:13:15 pm
content: Good point, I will mention this in my next message to him

author: SiliconWizard
author_rank: Super Contributor
timestamp: October 09, 2019, 06:26:26 pm
content: Quote from: GeorgeOfTheJungle on October 09, 2019, 02:02:53 pmYes, it was "2CV"."CV" in France is a tax system for cars, which is somewhat related to, but is definitely nothing like the power of the engine. It's calculated from various parameters, and influenced how much you had to pay to "register" the car, and then you had to pay for a specific tax once a year, which also depended on this figure. Now the yearly tax has been dropped for individual owners, but it still influences what you pay to register the car, what some companies will pay yearly to own it, and how much you typically pay for your car insurance.https://en.wikipedia.org/wiki/Tax_horsepowerTo give you an idea of the scale of this rating, a 15CV car is already typically a pretty powerful car (you're already in the sports car territory.)The power figure in HP SAE of the Citroen 2CV was from 9hp to 29hp depending on the version.And for the history:https://en.wikipedia.org/wiki/Citro%C3%ABn_2CVThe 2CV was produced from 1948 to 1990(!), and the tax rules had changed several times, so I'm not 100% sure the 2CV was still 2CV in the last years of production (I'd have to check), but it was when it got released.

author: FrankBuss
author_rank: Unknown
timestamp: October 14, 2019, 06:47:11 am
content: Today I could ask eBay to solve the case for the RAKIETA gold 12000 mAh Lithium Ionen Akku 3,7 V Typ 18650 battery,eBay auction: #371837870210. They immediately refunded it fully. This wasn't the problem, because the seller "allerlei-laden2012" offered to refund it, if I send it back, but he didn't want to pay the shipping cost, which is required by the eBay regulations, if the article doesn't match the description. Well, now I have at least the money. I asked the seller if he wants to pay me the shipping cost, if he wants his crap back.There are multiple negative ratings with similar behavior for this seller allerlei-laden2012, and he is still selling the battery. I wrote eBay that this is a scam, but they don't care. Lesson learned, I will use Aliexpress more often.

author: BravoV
author_rank: Super Contributor
timestamp: October 14, 2019, 07:04:08 am
content: Thanks, I will buy from those sellers your posted here, with the intention and plan to complain once I got them, and then get full refund.Not bad, free batteries, besides I am smart enough and you too, that knowing sending it back with them paying the cost in not an option from the beginning.Please, keep doing this kind of report, at the AliExpress too if you find more, I will follow your every steps while piling up free batteries, you are my hero.

author: FrankBuss
author_rank: Unknown
timestamp: October 14, 2019, 07:07:35 am
content: Thanks, I guess this is the only solution which helps. If everyone buys this crap and gets refunded, maybe someday they will get it that it doesn't make sense to sell it anymore.

author: FrankBuss
author_rank: Unknown
timestamp: October 14, 2019, 10:28:05 am
content: I just got another message from the seller for the rakieta accumulators, because I asked him if he still wants it back. He wrote that he didn't have to pay it back, he still has the money, and eBay just refunded me. This is not a good incentive to be honest on eBay as a seller, and another reason to use other services.

author: PlainName
author_rank: Super Contributor
timestamp: October 14, 2019, 10:33:29 am
content: QuoteProbably simpler and cheaper for Ebay in the short term, but it's not sustainable. If just a few people demand a refund it's a mere cost of doing business, but it lots of people do then they'll have to review they way they resolve these issues, and the only option open to them is to charge the vendor. So on that basis it makes sense to use Ebay even moreWell, more people demanding refunds, anyway. If one person ends up wanting a refund from 90% of his wins then pretty soon they'll be persona non grata.

author: SiliconWizard
author_rank: Super Contributor
timestamp: October 14, 2019, 03:10:18 pm
content: Quote from: dunkemhigh on October 14, 2019, 10:33:29 amYep, but I'd guess the fraction of all refund queries is low, and thus eBay doesn't care, as it's probably just background "noise" to them. Especially for cheap stuff. Many people, including myself, will not even bother (unless I'm in a very bad mood) asking for refund if I just paid a couple bucks for something... I may just leave negative feedback. More often, I even just don't bother to leave any feedback at all in these cases... the extra time it takes me being not even worthwhile compared to the price of the items.Sure if you're willing to enforce justice you may take those extra steps (even when they are not even "economically viable"), but I frankly don't know how many of us are ready to do so...

author: ESXi
author_rank: Regular Contributor
timestamp: October 23, 2019, 01:39:45 pm
content: I always have a big stash of 18650 cells, all from dead or used and working laptop battery packs.Got a 18650 charging board charged all batteries up (took me a while got like 40 batteries, mixed capacity, and brands). Did store them in a safe place, checked voltage for voltage drop and cleaned out the dead ones after a few months.So I have only spend like 2 dollar on a charging board and some electricity for charging the batteries. Green for the environment and my wallet !