Thanks Joe. Same results as I got with testing the REPT 280. I will also test 4 certified cells soon (not from SFK though) but I'm not expecting any other outcome from your test. With solar, high amps are not very common and all cells I have so far are perfect for solar storage. Even under high load, I have never seen a cell sagging. So certified cells are not for me. Not sure actually who would need them for DIY projects.
I was thinkin you tested a different brand but do remember you had similar results. I think if we had or found a less desirable cell in an order from Alibaba or where ever, we could show an example of a crappy cell. Ive heard and seen examples online but not in person....yet. True with solar during the day and other banks paralleled in, we wont see high discharge rate. Im more thinking of at night and a single bank. Either way it was fun to test the cells!🤘
I saw your video too, I think the clamp you are using is not good and should be changed to a lug. I learned about the ZKE charger/tester from your video, its a very nice device. I'm also a DIYer for me I don't have time to mess around with cells so I don't want to gamble with grade B. With grade A buy once cry once.
@@KoreanTacoKing The clamps are not the problem as it uses two, one for current and one for voltage sense. So regardless how bad the connection of the big clamp is, the result will be consistent.
@@AveRage_Joe SFK also send me two of the REPT 280 and also 2 of the EVE LF304, both certified automotive grade cells. Even with only one pack and drawing 120A, I have not seen such a voltage sag across the cells. If I had that, it was a bad bus bar connection and after fixing it, the cell was back to normal.
Real life testing is the only way to know if your cells are any good, for all you know all those cells were made as 304 ah cells then declassified to what they can get out of them. Thanks for your skills and testing it really helps.
Hrm, I went to the Ruipi Chinese site and they make a 302 cell, maybe the cell was a 302 and now being sold as a 280. Docan Power is doing the same thing with CATL 280 cells which are really CATL 302 with a scratched off QR code.
Yeah you wont know until testing. So I got all my cells before they had or listed anything over 300ah. Not saying your wrong tho😜 Thanks for the watch💥🤘
Well like I said, I purchased 16 rept cells and 16 lishen cells from alibaba. 2 different suppliers. I did capacity test all lishen cells. All capacity tested good. I have only capacity tested a total of 3 rept cells now. Again, those 3 capacity tested good. I will need to do a large test on all the rest to see what I truly have. For rept cells I purchased from alibaba, I have a link in description. The lishen cells are in a few videos ago.
I'm all about DIY for most things. I'm just about to start the solar journey and will be somewhat fast tracking to the off grid side of it after a new building and base system gets installed. But the SFK option is off the table as I see it. The American middlemen in the battery market suck the life and spirit out of DIY with their profiteering. As much as I enjoy DIY, I'm not investing all my time and effort into building batteries when for just a little more I can have a rack stack delivered, plug-n-play with warranty in hand. Once I'm up and running I may dig deeper into finding a fairly good source for cells to build out additional storage. I would like that a lot but it seems like these sellers come and go fairly regularly. Your critique was much appreciated though! Thanks!
Sun Fun Kits makes great kits too you should review them as well. Ohh they are out of stock again. I have the 280K and 304 Cells from them. Wonderful cells, I tested 316 using the zke ratings and if I do the wh/3.2 method that same cell is 320AH which matches the label exactly. I'm very pleased with everything I have from them.
I actually have a heated kit from them and waiting to release video. They wanted to wait a bit until stock comes back in. 100% great cells in that kit as well!🤘
Not supposed to have self locking nuts. If they do get hot, the plastic can melt. So strike one immediately for the EV certified... Second...batteries loose 1% per year no matter what you do to them, so 2 years is 6amp hours. I'd also like to know if during the certification they are tested under compression? If not, they actually degrade the cells. I.e. if you run cells without compression the first few cycles you permanently damage and make them swollen (not pressing out the gases). After a few cycles it no longer matters.
Your fantester is correct in Ah and not correct in Wh because you have a 2 Wire tester, which, because of voltage sag on wires calculates the Wh wrong, and actually shuts off a bit earlier (Ah also some mAh a bit too low =)))) ) There is a 4 Wire version, which is more or less the same accurate as charge/discharge tester you have
Good review. I do believe there is some peace of mind in paying a little more for the "certified" cells, especially if one's intent is to rely on their system, rather than use it as a convenience or hobby. Proper load testing should be done either way. Isn't the low cost of tech and test equipment amazing? I remember spending a month's salary on Fluke's most basic multi-meter years ago. What can't you do with a USB dongle and an app these days? Glad to see your feline co-star again! I haven't seen her in a few of your recent videos.
I’m guessing it’s Ok 👌 to save money. And I look at you and others doing the testing. And the community is watching the company’s are watching. So you test we watched and buy. We are seeing companies making improvements based off the results of your tests. We are in the catbird community with your feedback on testing. So thankfully 😅 we are benefiting from your help. Did I say thanks!
Yeah its ok to save money for sure! I just keep hearing horror stories. Maybe the random "bad" cell, people make moar of a stink over so it out there more. Hard to say. I would test the cells either way now. Maybe the companies are actually watching because improvments are being made! 🫣🤣💥🤘
IR is super important to maintain voltage under 1C load. 0.22mΩ should only give you a 60 millivolt drop but 0.30mΩ is 84 millivolts. Jump up to 1mΩ and you have a 280 millivolt drop. I kind of consider 3.300 to be the point where you should start because its the flat part of the curve so a high IR cell is going to drop under 3.000 volts right off the start really killing your watt hour number. Sun Fun Kits has some great videos on this. You'll see the Grade G(arbage) cells cant even maintain 3.000 volts under a high load (>0.5C) so I'm guessing their DC IR is over 4 times what it should be. Edit; Ah you watched the videos.
Yeah for sure watched his videos! That one cell he test was CRAZY Garbage. Was scared for my cells for a bit lol. I also just started the test at full charge since the EV cells were already full. Tried to make everything as equal as I could so needed to fully charge my cells. 🤘
@AveRage Joe @Anyone... FYI: I just learned recently myself that those cheap fan testers are nowhere near accurate unless you use one that is a "4-Wire" tester. (it will have 4 terminals instead of 2) 2 wires read the battery voltage directly, separate from the other 2 wires under load. This way the tester can read the actual battery voltage instead of reading it after the voltage drop of a normal 2wire tester, providing a much more accurate test. (Basically the same as the ZKE battery tester. Has two large wires and two small wires that connect to the battery terminals) Next time you use that tester compare the voltage reading on the screen versus reading it separately with a multimeter. You will notice the actual voltage of the battery is significantly higher than what the tester is displaying... obviously this will ruin the capacity test since the tester we'll hit it's cut off voltage too soon and the battery will have a bunch of capacity left... ( the difference will be much greater if you're using thinner wire or longer wire is this will cause a higher resistance in the wires itself...) Basically just like a battery monitor that has a separate shunt... 2 Wires goto the battery terminals to measure voltage and 2 wires go on the shunt to measure current separately. HOPE THIS HELPS SOMEONE USING THESE CHEAP 150W / 180W ELECTRONIC LOAD TESTERS
Yes you are 100% correct, for best results you want to use testers with 4 wires. When I purchased my fan tester a few years ago they didnt have a 4 wire option. The do have them now. You are also correct on the battery voltage of the tester vs the actual battery voltage and that the tester AND the test would be skewed since it would shut off sooner. Also with battery wires and lengths. All of this I was aware of a few years ago when I got the tester and tested all of my lishen cells. I first installed 2 short 10awg wires, then tested my first cell. First capacity test was crap, 2nd capacity test I had a volt meter on the cell through out the test and saw the voltage difference. On the low side when the tester thought it was done, the cell was still roughly 2.7v-2.8v. So then I adjusted the low cutoff little by little until the tester would stop when the cell would read 2.5v on my meter. I ended up setting the tester to 2.3v cuttoff. Then I was good to go!💥🤘
48 volts makes a far better system..Higher voltage lower amps..It's easier on the batteries and other components..More efficient....I think the grade B cells are fine for solar storage..The best of all are used cells or new, but 2nd hand...
Great vid, test & conclusion Joe, yours and Andy’s results are so close together. As a DIYer I have gone down the Amazon path with reasonable results, ie; 12 of 16 cells were delivered together in perfect order, but the other 4 cells did not arrive for another 3 weeks and 2 or 3 cells in that last box of 4 cells had some bloating & mismatch, not bad, but not as good as the 1st 12 cells to arrive together, I was pissy & should have pursued them for compo, as this was a critical aspect to the order, that they all arrive together as 16 cells. Anyhow, they aren’t too bad overall. I will be buying more in future, but I would suggest for anyone to buy extra cells if going this way as spares. I will probably get 20 or 24 cells next order, so I can have 2 good 48v 15kwh battery banks & use the suspect cells for a 24v bank in my RV. Cheers
Thanks! So the test that Ill be doing today on the 4 different cells. I think he also purchased from amazon(will confirm). 1 of his went up in smoke and I think all were slightly bloated. Ill try to have all of that info in the video. I agree that one should get a few extra cells and pick the best ones. Im surprised they sent a box of 4 cells later. How much time did it take for that last box?
I"m assuming the fan tester shows a much lower WH because the voltage will always be lower with he 2 wire testing. WIth 4 wire you'll have a higher voltage throughout so the wh number will be higher at the end of the test.
Good comparison Joe. @34:51 you mentioned you would ask 'a million more questions' of an Alibaba seller. Although I am not really expecting a million, what questions would you want to ask?
Thanks!!! So when I purchased from alibaba, I asked all sorts of questions. I asked about there test procedures, results(in amp hours), IR tests and results. I asked questions from there spec sheet. They would reply with pictures of the answer I was looking for from the spec sheet. They showed me videos of there testing area and the equipment used. How many amps used in the tests before shipping. Making sure all cells were the same or "matched" in capacity and Internal resistance. It actually went on for a few days. I also wanted to see how they handled all the questions. Every reply was quit cordial actually. Even with the language barrier. After I felt like I would be getting what they advertised, I purchased. I would do the same today but this time would also get an extra few cells just in case. We all know that there can be a lemon sometimes and with an extra few cells you can pick the best plus have an extra just in case some issue comes up in the future.
4-wire measurement will still be spot-on even with shitty alligator clips. So it's imperative that the 4 wires are separated as much as possible. The setups that uses 2 clips has the two sides insulated from each other, so the only point they meet are at the battery terminal itself. What you have done is negated this now. It probably won't matter much in this application, but you should keep it in mind.
Yeah testers with sense leads are moar accurate for sure! Are you saying I should remove the sense wires from the lugs and use alligator clips to attach to the same point? Or did I misread what you are saying?
Thank you for the review, wow this was in-depth. Yes the REPT cells are nice and you have some good ones from Alibaba, I actually think you got new old stock. Some times grade A cells after 2 years on the shelf are sold as grade B simply due to age. These are for the most part indistinguishable from certified cells. Other times not so much. I think people should consider grade A as the cell + an insurance policy that guarantees a minimum performance level. Good grade B will perform very close to certified cells, however, there is a chance you can get meh or bad grade B cells. The chance can vary from batch to batch and supplier to supplier. But ultimately, realize if the Alibaba sellers actually were forced to disclose these are grade B cells, regardless of how close they perform to certified cells, there sales would plummet. So ultimately, I think for us its not a matter of how close grade B can be to an EV grade cell but rather should sellers be allowed to mislead buyers and claim something that its not.
Thanks Man! I tried to be as in-depth as I could be! I think I got pretty lucky! I still need to test the others I have tho. So speaking of a bad grade B cell, a buddy had a cell go up in smoke not to long ago. Not 100% sure what actually happened. I am speculating it was over charged somehow. Headed over to his house tomorrow to do some testing. Bringing the EV REPT, my REPT and Lishen to compare!!! Another video on the way!!
The thing about testing in Wh is suspicious. I think SFK just created a lot of confusion about this. I'm undecided if it was accidental or intentional. Cells are designed and rated in Ah. The chemical reaction in the battery stores a given amount of electric charge, typically measured in Coulombs in physics text books, but also measured in Amp * hour or Amp * second. By definition, a current of 1 Amp through a wire tells you that 1 Coulomb of charge is transferred in each second through that wire. Then you measure the battery average voltage during a discharge cycle and that becomes the "nominal voltage" (sticker value) of the battery. So if you multiply the average voltage and the Ah, you get the Wh.
Watts = Amps * Volts. | Watt-hours = Amp-hours * Nominal voltage. Learn the math. AH without a nominal voltage means nothing, otherwise we have an infinite AH battery for you at 0 volts. And NO! Batteries are rated in Watt-hours not AH, which is why every electric car lists its capacity in KW and now Killo-Amp-hours. The same is for your utility bill, and the same is FOR UN3480 which is the international standard for shipping. The information we have is directly form the manufacture. You have been led astray because you have followed conventional youtube mindset.
@@sfkenergy You tell me to"learn the math" and then you repeat my last statement. That's interesting. Batteries are rated and designed by the amount of electrical charge they can hold (Coulomb or Amp*second or Amp*hour etc). That is their defining characteristic. The Victron Shunt measures and defines state-of-charge based on Amp-hour and they know what they're doing. Utility bills are given in kWh because that is their defining characteristic and the main cost indicator to the utility. EV batteries are specified in Ah in technical service documents and in kWh (not kW, as you said) in marketing materials because end-users want to be able to make the connection with the utility bill and how much it costs to run per mile. PS: This is not "conventional youtube mindset". This is a Physics and an Electrical Engineering Degree. Batteries have been rated in Ah waaay before the LFP technology was born. Batteries have been rated in Ah way before even youtube existed.
@@danielardelian2 Sorry but you are not correct, apply the above equation you will see the cells are rated properly. I will not continue to argue with you just provide accurate information that checks out with math.
All I know is SFK talks to the manufactures of the cells he purchases. They told them that they test in watt hours. Thats all I was saying. In the end tho for most of us DIYers, the number on the tester is good enough.💥🤘
@@AveRage_Joe mega cool 😎 Ich schätze deine oder Andy seine Tests sehr interessant.. Und hab selber schon viele Tests hinter mir.. Aber sehr viel kleiner. Joe hinter dir steht oben auf dem Schrank immer der große halter für 18650.. Steck doch aus bunten Zellen dort Boooom oder Joe hinein.. Und noch so bisl LED dazu.. So als Werbung..
@@brianthompson9485 it depends. My two Sunny Island inverters can pull 23kW peak if needed (including from solar and batteries). And with a heat pump, electric car, oven etc it's easily possible to pull 200A. The limit from the batteries is about 10kW, which is over 200A. Err, lol
Great video, I've been running REPT 280 cell for about a year and a half now in a 2p16s configuration with no issues. I'm off-grid in northeast Alberta Canada. Just curious what was the difference in cost/cell?
NICE!!! You running a whole house or cabin, garage ect? Ill be there soon! So for my alibaba cellls I paid $87.50 each. The EV grade are $194 each so there $100 more per cell.
@@AveRage_Joe yes for my house. It's a small 1000sq ft story and half two bedroom house. It's in-floor heating is done with a tankless water heater and propane for my stove. All LED lightbulbs with the normal electric appliances (fridge, microwave, ect). We use a Magnum inverter with a Midnite solar charge controller and a 4.6kw array. Our generator runs with the REPT cells for maybe 30hrs all winter. Days are really short here in the winter.
I'm shopping around for cells myself right now. I'm wondering what the real world performance difference is between the aluminum cased cells, and the plastic cased cells would be(other than size/weight). I'm doing a strange thing where I want to run a 1200va victron inverter and a 3000 multiplus in parallel. I want the 1200 Phoenix to handle the bulk of the kwh's(using limited shore power connection setting in multiplus) and connected to a lithium battery bank. And the multiplus will handle surge/backup with a lead acid bank. For my lithium bank I want 12 cells 200ah or more, in a parallel 12v bank. That way I can build 3 separate batteries and if I need to bring one offline for maintenance/repair it's not the end of the whole bank. Also splitting the load 3 ways would be a normal max of 30amps each 12v bank. I have 1600watts worth of pannels currently but only 600w of 12volt charging current capability. I'll add another 400w(vicron 100/30) eventually to the current victron 100/30 and 75/15.
SF= 240A was about 3.30 to 3.12 so 180 millivolts. The cells themselves should drop ~70 millivolts so I guess the rest is wire and connections Alibaba=~240A (tad more because of lower voltage) drops from 3.32 to 3.10 so 220 millivolts So looks like your cells are indeed just slightly higher in IR than the SF cells, you actually got really lucky Edit: WOW the price you got those Alibaba REPT's is insane for how well they performed near 1C. They're essentially the cream of the crop for Grade B
REPT cells are not as strong as EVE cells, but the market wants Capacity, Capacity, Capacity so the REPT delivers in that regard. For Maximum Performance the EVE LF304 will hold voltage much stronger.
Yeah I would say I did pretty good. Just checked the invoice and I paid $81.50each. I only purchased those at the time cause they were the CHEAPEST I could find...no joke. Everything else was either sold out or more then I wanted to pay. Keep in mind I still need to test the others lol
i think you are comparing Lf280 with Lf280N... thats the size and age difference between your ali and grade A. there is 5 versions of Lf280.. so better know what you are comparing to. thank you for very good test even though
BigBattery has a Rhino battery thats 14kwh. That is there version of a Tesla powerwall. Has moar capacity and cheaper! Signature Solar has some good deals on Solar Panels. If you want used solar, I got mine from Santan Solar.
So basically on Alibaba when they advertise "A" cells it actually means "it's almost the same as a real A cell". Is that enough difference to make a difference?
For the most part yes that is what I gather. Many can just about be a grade A but failed the "testing" which could have been something very minor. I would bet there are a few that advertise A but are actual B. I personally think most of those are on aliexpress. Would I buy from alibaba again YES. If I wanted 100% precision I would buy real grade A from SFK.
Thanks for doing this test. I have some slightly bloated CATL 305ah cells which arived like that and i preformed the same tests as you and got almost the exact same results. I have read quite a few peeps with bloated CATL cells and doesn't seem to be an issue?
im only seeing the Certified EV/ESS cells from SFK if its that big of a deal why are there no other tubers doing it and it cost 58-ish dollars per a cell more i haven't seen a vid to make the cost worth it to me
I just bought my first lifepo4 cells, Grade B CALB 280A and there is that they need compression but not sure is it ok if i put those cells to plastic case so that they are in tight fit, like sunfunkits have. After all, voltage is the same in all cells and no any bulging.
Yeah you can 100% put in a case for SFK or like SFK. They use foam on the sides so it does allow the cells to squeeeeeeze in there! I have there 12v kit and I had ZERO issues putting in the cells!🤘
@@niemma2ou are correct, some BMS balancers (passive 150mA) are all but useless on these cells and they need at least 2A or more active balancer, with parameters setup correctly for best results. I use the JK BMS’s with 2A active balancing on a 24v & a 48v systems and like how well they work & balance so far, it has a nice app too, although it does tend to jam on my Iphone a bit, otherwise I love JK. JBD do have some nice BMS’s too of course, but I have had some issues with the cheaper versions I found in some cheapo 12v batteries (28 cylinderical lipo4 cells in each), when I added JK BMS’s to these batteries it fixed their badly imbalanced cells within a day & these cheap batteries are now 2 quite reasonable 24v 5kwh battery packs, not the best, but ok for the requirements. Compression is not that big a deal, unless it is for mobile use, main thing is that it is all reasonably secure however u mount or locate ur new cells. Also agree on NOT using Daly. Hope this helps, have fun!
I recently bought some cells from Docan and the QR code reader I have on my phone said that they were manufactured in Sept. of 2024! What do you make of that?
ESS cells are basically 3rd tier used. With LSEV being above that and HSEV being above that. HSEV are still used cells still very good but more expensive. Chinas naming scheme of calling cells grade A new etc is all misleading. Every cell us diy type would purchase are all very used but cheap and are good enough. Just understand that what you buy is very used. If i am buying i am looking for LSEV. They cost more but are better than ESS and is a fair balance of life vs cost.
Honestly both are great. REPT is a little cheaper. One thing I will mention tho is a lot of complete batteries like server rack batteries or others, they always use EVE. Not sure why but they do. If I didnt have a budget, Id go EVE. If your broke like me, Id go REPT🤭😆
Fan tester Wh results are bad because they do not have separate sensing wires, and system resistance causes a voltage lower than OCV to be used in the Wh calc.
Basically what you are saying is that you paid twice as much for "real grade A"' from an American supplier while only having 10 Ah more from them. Not convinced as to who scammed you.
these batterys loose the certification from the moment sunfunkits welded the poles onto the battery. Automotive cells some without terminal poles and are tested on the max amp. With these single stud poles thats not possible.
Guess if you are using that inverter for your system, and you are maxing it out, and your batteries are not sagging with the test, then you should not have a problem.
REPT cells have strange behavior they seem balanced above 75% lower than 75% voltage difference will be much more i have cells go 100mv lower than other cells i am trying to top balance them again and test.
What bms shoyld I get for my car audio bank. I have 160Ah of spim08hp cells and I want to keep them balanced and monitor from my phone. Looking to have 16000 to 20000 watts. I'm also running 2 400A alternators. Hope you c can help me out. Thanks
Taking the Wh reading and dividing it with the nominal voltage of the cell is just wrong. During a discharge (and you can pick e.g. any of Andy's curves he recorded as example) the voltage stays above 3.2V for the majority of the time (over 60% iirc). If the voltage were truly 3.2V over the entire discharge, you could do this - even if it were average at 3.2V - but because it's over 3.2V for most of the time you're getting a skewed result in favor of higher Ah results. The reason they're skewed is in the definition of nominal voltage: the nominal voltage is measured at the mid point between full charged and fully discharged based on a 0.2C discharge - so unless you discharge these particular 304Ah cells at 60A, you're not having a 3.2V nominal voltage over the curve, and you can't just divide these results by the nominal voltage. In fact, if you take the Wh reading of your capacity test (with the ZKE) and divide that by the Ah measurement of the same test, you can see e.g. that cell 1 has an average voltage of 3.22V, etc. The whole reason of rating a battery in Ah is because it takes voltage and losses out of the equation: any bad connection, wire resistance, etc. will impact the Wh readings (especially on devices without separate voltage sense wires like that fan one), but will still produce accurate Ah readings (the current is the same everywhere in the circuit).
Let's be clear, SFK add the terminals after they receive the cells from Eve, and Eve do not approve those stud type of terminals on those cells. It might be worth contacting Eve to verify what I am suggesting here. My point is if you take a "certified automotive grade" cell and do not comply with the manufacturer's specifications, are they still automotive grade? Maybe that is just a technicality if they test the same with both terminal types? I would suggest having accurate information is a good start though.
@@Foxfried Sorry I don't make any sense to you. The answer you are looking for is a buyer/reseller would be a manufacturer, not the general public, and either laser weld the cells together, or laser weld their own terminal post, or drill and tap a hole to insert a threaded stud. I hope that helps clear things up for you.
Ray is the reason I just bought my cells from Jenny Wu. I don't think I would go that route again. Previously I bought from Amy Wan who a lot of the guys on Will Prowse DIY Forum purchase from. Those cells I was very happy with. The only reason I went with Jenny Wu was because I could get them quicker. If I would have had months to wait for the cells I would have gotten them from Amy.
@@AveRage_Joe I have not. Complicated situation. The cells were delivered in PA where our cabin with the off grid solar system is. I live in Florida!! I was in PA two weeks ago for a very short visit due to a family issue. I set forth to top balance but ran out of time. I had to return to FL and won't be back for another month. At that time I will top balance and check capacity.
So you are comparing, automotive grade meaning high current new batteries with solar storage lower current older batteries. Not really a good test setup to compare. It is apples and pears comparing.
These are not grade B cells so this would not apply. Are you some ebay-er trying to sell stuff and SFK is making life hard? I'm reading comments now and it appears most of the people that are the most upset are people selling grade B on eBay and Amazon are angry that buyers keep asking for test reports and other stuff the grade B pawners don't have to offer.
SFK is charging a big premium for pretty much the same cells, and bit of paperwork. And when @RayBuildsCoolStuff did a capacity test on SFK, and found disappointing results, he got threatened with a lawsuit by SFK. Any DIYer who goes for some of the known good alibaba providers, there seems little value in SFK.
🤣 Ohh you mean the guy that goes around telling people to buy docan, who has been busted with scratched off QR codes that were re-lasered? Yeah have fun with those junk grade B 304 that have been relazered with 280K counterfeit qr codes.
A or B or Automotive is just marketing. They all came out of the same factory. If everyone is selling the same thing, you have to differentiate yourself from the competition. Buy the cheapest and get 1 more with the money you save. Check out Ray builds cool stuff sfk battery test
That makes total sense, the manufacturer just decides to scratch off the QR code because they have a mental disability. Or Perhaps your are just blinded by your desire to save a few $... This test directly contradicts every thing Ray builds cool stuff does, as he goes around preaching reject cells are better than EV, these guys both use the same tester, why such different results?
I agree with you on the cells come from the same factory however there is a difference in A, B ect... Having said that there is a difference doesnt mean the cells wont test about the same. Grade A passed or meets the testing requirements(I dont know what those requirements are). If the cell doesnt meet those then it is automatically a grade B. Like Ive said in some of my other videos, I dont know ALL the battery things and learn stuff all the time. When I purchased the alibaba rept cells, I purchased the cheapest cells I could find!! I would 100% get an extra few cells next time to pick the best ones and have an extra if something went wrong later on!💥🤘
Thanks Joe. Same results as I got with testing the REPT 280. I will also test 4 certified cells soon (not from SFK though) but I'm not expecting any other outcome from your test. With solar, high amps are not very common and all cells I have so far are perfect for solar storage. Even under high load, I have never seen a cell sagging. So certified cells are not for me. Not sure actually who would need them for DIY projects.
I was thinkin you tested a different brand but do remember you had similar results. I think if we had or found a less desirable cell in an order from Alibaba or where ever, we could show an example of a crappy cell. Ive heard and seen examples online but not in person....yet. True with solar during the day and other banks paralleled in, we wont see high discharge rate. Im more thinking of at night and a single bank. Either way it was fun to test the cells!🤘
I saw your video too, I think the clamp you are using is not good and should be changed to a lug. I learned about the ZKE charger/tester from your video, its a very nice device. I'm also a DIYer for me I don't have time to mess around with cells so I don't want to gamble with grade B. With grade A buy once cry once.
Morning Andy, how crazy is the weather. 37 degree tomorrow.
@@KoreanTacoKing The clamps are not the problem as it uses two, one for current and one for voltage sense. So regardless how bad the connection of the big clamp is, the result will be consistent.
@@AveRage_Joe SFK also send me two of the REPT 280 and also 2 of the EVE LF304, both certified automotive grade cells.
Even with only one pack and drawing 120A, I have not seen such a voltage sag across the cells. If I had that, it was a bad bus bar connection and after fixing it, the cell was back to normal.
Real life testing is the only way to know if your cells are any good, for all you know all those cells were made as 304 ah cells then declassified to what they can get out of them. Thanks for your skills and testing it really helps.
Hrm, I went to the Ruipi Chinese site and they make a 302 cell, maybe the cell was a 302 and now being sold as a 280. Docan Power is doing the same thing with CATL 280 cells which are really CATL 302 with a scratched off QR code.
Yeah you wont know until testing. So I got all my cells before they had or listed anything over 300ah. Not saying your wrong tho😜 Thanks for the watch💥🤘
Im not a fan of the CATL cells. Well I should say I havent tested any but it seems like I hear issues with those🤷♂️
Thanks for the info, I am presently contemplating purchasing 32 cells from Alibaba and you have provided some food for thought.
Well like I said, I purchased 16 rept cells and 16 lishen cells from alibaba. 2 different suppliers. I did capacity test all lishen cells. All capacity tested good. I have only capacity tested a total of 3 rept cells now. Again, those 3 capacity tested good. I will need to do a large test on all the rest to see what I truly have.
For rept cells I purchased from alibaba, I have a link in description. The lishen cells are in a few videos ago.
I'm all about DIY for most things. I'm just about to start the solar journey and will be somewhat fast tracking to the off grid side of it after a new building and base system gets installed. But the SFK option is off the table as I see it. The American middlemen in the battery market suck the life and spirit out of DIY with their profiteering. As much as I enjoy DIY, I'm not investing all my time and effort into building batteries when for just a little more I can have a rack stack delivered, plug-n-play with warranty in hand.
Once I'm up and running I may dig deeper into finding a fairly good source for cells to build out additional storage. I would like that a lot but it seems like these sellers come and go fairly regularly.
Your critique was much appreciated though!
Thanks!
Sun Fun Kits makes great kits too you should review them as well. Ohh they are out of stock again. I have the 280K and 304 Cells from them. Wonderful cells, I tested 316 using the zke ratings and if I do the wh/3.2 method that same cell is 320AH which matches the label exactly. I'm very pleased with everything I have from them.
I actually have a heated kit from them and waiting to release video. They wanted to wait a bit until stock comes back in. 100% great cells in that kit as well!🤘
I love direct comparison tests!
I thought it was a Great test! Thanks for watching!!💥🤘
Not supposed to have self locking nuts. If they do get hot, the plastic can melt. So strike one immediately for the EV certified...
Second...batteries loose 1% per year no matter what you do to them, so 2 years is 6amp hours.
I'd also like to know if during the certification they are tested under compression? If not, they actually degrade the cells. I.e. if you run cells without compression the first few cycles you permanently damage and make them swollen (not pressing out the gases).
After a few cycles it no longer matters.
Great video Joe- As I was watching, was thinking I wander how they compare under heavy load- Then BOOOM- You did the test.
I got chu!💥🤘
Your fantester is correct in Ah and not correct in Wh because you have a 2 Wire tester, which, because of voltage sag on wires calculates the Wh wrong, and actually shuts off a bit earlier (Ah also some mAh a bit too low =)))) )
There is a 4 Wire version, which is more or less the same accurate as charge/discharge tester you have
Great job as usual Joe. This video was excellent.
Thanks! It took much longer in real life lol. I thought it had great info and I learned a lot!🫣🤠
Good review. I do believe there is some peace of mind in paying a little more for the "certified" cells, especially if one's intent is to rely on their system, rather than use it as a convenience or hobby. Proper load testing should be done either way.
Isn't the low cost of tech and test equipment amazing? I remember spending a month's salary on Fluke's most basic multi-meter years ago. What can't you do with a USB dongle and an app these days?
Glad to see your feline co-star again! I haven't seen her in a few of your recent videos.
the "certified" cells is 58ish $ more per a cell in my book that's not a little more and SFK is the only one that i have found that's doing it
I’m guessing it’s Ok 👌 to save money. And I look at you and others doing the testing. And the community is watching the company’s are watching. So you test we watched and buy. We are seeing companies making improvements based off the results of your tests. We are in the catbird community with your feedback on testing. So thankfully 😅 we are benefiting from your help. Did I say thanks!
They sell mostly to other businesses and government agencies so for those people they require certifications.
Yeah its ok to save money for sure! I just keep hearing horror stories. Maybe the random "bad" cell, people make moar of a stink over so it out there more. Hard to say. I would test the cells either way now. Maybe the companies are actually watching because improvments are being made! 🫣🤣💥🤘
Another great informative video from ARJ
Thanks and Appreciate that!!💥🤘
Always enjoy the videos
Appreciate that!!💥🤘
Excellent education! Thank you!
Thanks for Watching!🤘
Thanks for the info and links I have been looking for High quality cells
Morning Joe, SFK stuff, sorry fun. From sunny hot Australia. 37 degree here tomorrow.
Yooooo! Is that hot or cold🤣🫣
@@AveRage_Joe Degree celsius it is getting to the hot side.
No hay en el mercado grado A esas celdas las utiliza el fabricante, solo puedes comprar grado B y grado C
Great job, as always you make it look so easy.
🤔💭💣💥
Thanks! The power of video editing makes it look so easy and effortless 😆💥🤘
IR is super important to maintain voltage under 1C load. 0.22mΩ should only give you a 60 millivolt drop but 0.30mΩ is 84 millivolts. Jump up to 1mΩ and you have a 280 millivolt drop. I kind of consider 3.300 to be the point where you should start because its the flat part of the curve so a high IR cell is going to drop under 3.000 volts right off the start really killing your watt hour number.
Sun Fun Kits has some great videos on this. You'll see the Grade G(arbage) cells cant even maintain 3.000 volts under a high load (>0.5C) so I'm guessing their DC IR is over 4 times what it should be.
Edit; Ah you watched the videos.
Yeah for sure watched his videos! That one cell he test was CRAZY Garbage. Was scared for my cells for a bit lol. I also just started the test at full charge since the EV cells were already full. Tried to make everything as equal as I could so needed to fully charge my cells. 🤘
Nice batts :-)
Thanks for the video !!!
Thanks for watching!🤘
HOWdy A-J , ...
Thanks for the Comparison TEST
COOP
the WiSeNhEiMeR from Richmond, INDIANA
...
Thanks Man! Appreciate the Watchy watch!!💥🤘
As always another great video
Thanks Man! Appreciate the watch!💥🤘
I'm just going to buy the jakiper rack mount batteries.. local distributor so it can go back easy if it has to
Those are great batteries as well!🤘
They sent me a message. I'll see if I can get a bulk discount
If its from opsolarbattery, I did a video on there powerwall style battery and LV6548 inverter. I should have a link and discount code in those vids.
@AveRage Joe
@Anyone...
FYI: I just learned recently myself that those cheap fan testers are nowhere near accurate unless you use one that is a "4-Wire" tester. (it will have 4 terminals instead of 2)
2 wires read the battery voltage directly, separate from the other 2 wires under load. This way the tester can read the actual battery voltage instead of reading it after the voltage drop of a normal 2wire tester, providing a much more accurate test.
(Basically the same as the ZKE battery tester. Has two large wires and two small wires that connect to the battery terminals)
Next time you use that tester compare the voltage reading on the screen versus reading it separately with a multimeter. You will notice the actual voltage of the battery is significantly higher than what the tester is displaying... obviously this will ruin the capacity test since the tester we'll hit it's cut off voltage too soon and the battery will have a bunch of capacity left... ( the difference will be much greater if you're using thinner wire or longer wire is this will cause a higher resistance in the wires itself...)
Basically just like a battery monitor that has a separate shunt... 2 Wires goto the battery terminals to measure voltage and 2 wires go on the shunt to measure current separately.
HOPE THIS HELPS SOMEONE USING THESE CHEAP 150W / 180W ELECTRONIC LOAD TESTERS
Yes you are 100% correct, for best results you want to use testers with 4 wires. When I purchased my fan tester a few years ago they didnt have a 4 wire option. The do have them now.
You are also correct on the battery voltage of the tester vs the actual battery voltage and that the tester AND the test would be skewed since it would shut off sooner. Also with battery wires and lengths. All of this I was aware of a few years ago when I got the tester and tested all of my lishen cells. I first installed 2 short 10awg wires, then tested my first cell. First capacity test was crap, 2nd capacity test I had a volt meter on the cell through out the test and saw the voltage difference. On the low side when the tester thought it was done, the cell was still roughly 2.7v-2.8v. So then I adjusted the low cutoff little by little until the tester would stop when the cell would read 2.5v on my meter. I ended up setting the tester to 2.3v cuttoff. Then I was good to go!💥🤘
48 volts makes a far better system..Higher voltage lower amps..It's easier on the batteries and other components..More efficient....I think the grade B cells are fine for solar storage..The best of all are used cells or new, but 2nd hand...
Great vid, test & conclusion Joe, yours and Andy’s results are so close together.
As a DIYer I have gone down the Amazon path with reasonable results, ie; 12 of 16 cells were delivered together in perfect order, but the other 4 cells did not arrive for another 3 weeks and 2 or 3 cells in that last box of 4 cells had some bloating & mismatch, not bad, but not as good as the 1st 12 cells to arrive together, I was pissy & should have pursued them for compo, as this was a critical aspect to the order, that they all arrive together as 16 cells. Anyhow, they aren’t too bad overall.
I will be buying more in future, but I would suggest for anyone to buy extra cells if going this way as spares. I will probably get 20 or 24 cells next order, so I can have 2 good 48v 15kwh battery banks & use the suspect cells for a 24v bank in my RV. Cheers
Thanks! So the test that Ill be doing today on the 4 different cells. I think he also purchased from amazon(will confirm). 1 of his went up in smoke and I think all were slightly bloated. Ill try to have all of that info in the video. I agree that one should get a few extra cells and pick the best ones. Im surprised they sent a box of 4 cells later. How much time did it take for that last box?
@AveRage_Joe
He noted it was 3 weeks.
He should at least post a review about their services.
🤔💭💣💥
Very encouraging info. Well done.
Thank You!!!🤠💥🤘
I feel your relief!
🤣🤣I Know RIGHT!!!🫣🤘
I"m assuming the fan tester shows a much lower WH because the voltage will always be lower with he 2 wire testing. WIth 4 wire you'll have a higher voltage throughout so the wh number will be higher at the end of the test.
these are certificated and originally they come from Alibaba but SKS is doing a roaring with their tester.
Good comparison Joe.
@34:51 you mentioned you would ask 'a million more questions' of an Alibaba seller.
Although I am not really expecting a million, what questions would you want to ask?
Thanks!!! So when I purchased from alibaba, I asked all sorts of questions. I asked about there test procedures, results(in amp hours), IR tests and results. I asked questions from there spec sheet. They would reply with pictures of the answer I was looking for from the spec sheet. They showed me videos of there testing area and the equipment used. How many amps used in the tests before shipping. Making sure all cells were the same or "matched" in capacity and Internal resistance. It actually went on for a few days. I also wanted to see how they handled all the questions. Every reply was quit cordial actually. Even with the language barrier. After I felt like I would be getting what they advertised, I purchased. I would do the same today but this time would also get an extra few cells just in case. We all know that there can be a lemon sometimes and with an extra few cells you can pick the best plus have an extra just in case some issue comes up in the future.
4-wire measurement will still be spot-on even with shitty alligator clips. So it's imperative that the 4 wires are separated as much as possible. The setups that uses 2 clips has the two sides insulated from each other, so the only point they meet are at the battery terminal itself. What you have done is negated this now. It probably won't matter much in this application, but you should keep it in mind.
Yeah testers with sense leads are moar accurate for sure! Are you saying I should remove the sense wires from the lugs and use alligator clips to attach to the same point? Or did I misread what you are saying?
Always remember to hook up remote sense for accurate Wh figures.
My fan tester doesnt have the option but I think the new versions do!🤘
@@AveRage_Joe yes, the newer ones do.
Long mate, mine are long. Back to the server 2.oooo dear for me😂😊. Oh better test the new current tester😊. Which is as good as a Victon hopefully.
Let me know how the new meter goes!
@@AveRage_Joe Should be up now. I have a link for Andreas youtube, who tested it.
Thank you for the review, wow this was in-depth. Yes the REPT cells are nice and you have some good ones from Alibaba, I actually think you got new old stock. Some times grade A cells after 2 years on the shelf are sold as grade B simply due to age. These are for the most part indistinguishable from certified cells. Other times not so much. I think people should consider grade A as the cell + an insurance policy that guarantees a minimum performance level. Good grade B will perform very close to certified cells, however, there is a chance you can get meh or bad grade B cells. The chance can vary from batch to batch and supplier to supplier.
But ultimately, realize if the Alibaba sellers actually were forced to disclose these are grade B cells, regardless of how close they perform to certified cells, there sales would plummet. So ultimately, I think for us its not a matter of how close grade B can be to an EV grade cell but rather should sellers be allowed to mislead buyers and claim something that its not.
Thanks Man! I tried to be as in-depth as I could be! I think I got pretty lucky! I still need to test the others I have tho. So speaking of a bad grade B cell, a buddy had a cell go up in smoke not to long ago. Not 100% sure what actually happened. I am speculating it was over charged somehow. Headed over to his house tomorrow to do some testing. Bringing the EV REPT, my REPT and Lishen to compare!!! Another video on the way!!
@@AveRage_Joelook forward to ur results of that
The thing about testing in Wh is suspicious. I think SFK just created a lot of confusion about this. I'm undecided if it was accidental or intentional.
Cells are designed and rated in Ah. The chemical reaction in the battery stores a given amount of electric charge, typically measured in Coulombs in physics text books, but also measured in Amp * hour or Amp * second.
By definition, a current of 1 Amp through a wire tells you that 1 Coulomb of charge is transferred in each second through that wire.
Then you measure the battery average voltage during a discharge cycle and that becomes the "nominal voltage" (sticker value) of the battery.
So if you multiply the average voltage and the Ah, you get the Wh.
Watts = Amps * Volts. | Watt-hours = Amp-hours * Nominal voltage. Learn the math. AH without a nominal voltage means nothing, otherwise we have an infinite AH battery for you at 0 volts. And NO! Batteries are rated in Watt-hours not AH, which is why every electric car lists its capacity in KW and now Killo-Amp-hours. The same is for your utility bill, and the same is FOR UN3480 which is the international standard for shipping.
The information we have is directly form the manufacture. You have been led astray because you have followed conventional youtube mindset.
@@sfkenergy You tell me to"learn the math" and then you repeat my last statement. That's interesting.
Batteries are rated and designed by the amount of electrical charge they can hold (Coulomb or Amp*second or Amp*hour etc). That is their defining characteristic.
The Victron Shunt measures and defines state-of-charge based on Amp-hour and they know what they're doing.
Utility bills are given in kWh because that is their defining characteristic and the main cost indicator to the utility.
EV batteries are specified in Ah in technical service documents and in kWh (not kW, as you said) in marketing materials because end-users want to be able to make the connection with the utility bill and how much it costs to run per mile.
PS: This is not "conventional youtube mindset". This is a Physics and an Electrical Engineering Degree. Batteries have been rated in Ah waaay before the LFP technology was born. Batteries have been rated in Ah way before even youtube existed.
@@danielardelian2 Sorry but you are not correct, apply the above equation you will see the cells are rated properly. I will not continue to argue with you just provide accurate information that checks out with math.
All I know is SFK talks to the manufactures of the cells he purchases. They told them that they test in watt hours. Thats all I was saying. In the end tho for most of us DIYers, the number on the tester is good enough.💥🤘
I test lead acids with a 3kw inverter and a 2kw fan heater, and thats how I would be testing those
Thats a great way to test high amp draw for sure!!!💥🤘
Hi AveRage. May I ask what the app is that scans the QR code? It's very important for me. Thank you very much for your help
KAAA BOOOOM😂😂😂 guter Name für den Batrium 😂😂😂
You are the FIRST to notice!🤣🤣🤣KAAA💥💥💥💥💥🤘
@@AveRage_Joe mega cool 😎
Ich schätze deine oder Andy seine Tests sehr interessant.. Und hab selber schon viele Tests hinter mir.. Aber sehr viel kleiner.
Joe hinter dir steht oben auf dem Schrank immer der große halter für 18650.. Steck doch aus bunten Zellen dort Boooom oder Joe hinein.. Und noch so bisl LED dazu.. So als Werbung..
SunFunKits tested at 200A and above, and the difference was way higher.
How many people are pulling 200 amps out of their cells? lol
@@brianthompson9485 it depends. My two Sunny Island inverters can pull 23kW peak if needed (including from solar and batteries). And with a heat pump, electric car, oven etc it's easily possible to pull 200A. The limit from the batteries is about 10kW, which is over 200A.
Err, lol
Great video, I've been running REPT 280 cell for about a year and a half now in a 2p16s configuration with no issues. I'm off-grid in northeast Alberta Canada.
Just curious what was the difference in cost/cell?
NICE!!! You running a whole house or cabin, garage ect? Ill be there soon! So for my alibaba cellls I paid $87.50 each. The EV grade are $194 each so there $100 more per cell.
@@AveRage_Joe yes for my house. It's a small 1000sq ft story and half two bedroom house. It's in-floor heating is done with a tankless water heater and propane for my stove. All LED lightbulbs with the normal electric appliances (fridge, microwave, ect). We use a Magnum inverter with a Midnite solar charge controller and a 4.6kw array. Our generator runs with the REPT cells for maybe 30hrs all winter. Days are really short here in the winter.
I'm shopping around for cells myself right now. I'm wondering what the real world performance difference is between the aluminum cased cells, and the plastic cased cells would be(other than size/weight).
I'm doing a strange thing where I want to run a 1200va victron inverter and a 3000 multiplus in parallel. I want the 1200 Phoenix to handle the bulk of the kwh's(using limited shore power connection setting in multiplus) and connected to a lithium battery bank. And the multiplus will handle surge/backup with a lead acid bank.
For my lithium bank I want 12 cells 200ah or more, in a parallel 12v bank. That way I can build 3 separate batteries and if I need to bring one offline for maintenance/repair it's not the end of the whole bank. Also splitting the load 3 ways would be a normal max of 30amps each 12v bank. I have 1600watts worth of pannels currently but only 600w of 12volt charging current capability. I'll add another 400w(vicron 100/30) eventually to the current victron 100/30 and 75/15.
Cutting off the alligator clips was not necessary because voltage is measured with the separate line.
SF= 240A was about 3.30 to 3.12 so 180 millivolts. The cells themselves should drop ~70 millivolts so I guess the rest is wire and connections
Alibaba=~240A (tad more because of lower voltage) drops from 3.32 to 3.10 so 220 millivolts
So looks like your cells are indeed just slightly higher in IR than the SF cells, you actually got really lucky
Edit: WOW the price you got those Alibaba REPT's is insane for how well they performed near 1C. They're essentially the cream of the crop for Grade B
REPT cells are not as strong as EVE cells, but the market wants Capacity, Capacity, Capacity so the REPT delivers in that regard. For Maximum Performance the EVE LF304 will hold voltage much stronger.
Yeah I would say I did pretty good. Just checked the invoice and I paid $81.50each. I only purchased those at the time cause they were the CHEAPEST I could find...no joke. Everything else was either sold out or more then I wanted to pay. Keep in mind I still need to test the others lol
The EVE cells you tested in your video were AMAZING!!!
i think you are comparing Lf280 with Lf280N... thats the size and age difference between your ali and grade A.
there is 5 versions of Lf280.. so better know what you are comparing to.
thank you for very good test even though
Highstar lipo4 company executive said.. laser weld give 6000 life cycle and bolt model 3500 life cycle😢😢
Great video!
Thanks Man!!!💥🤘
Do you know of any American made batteries for power wall or solar panels. Except Tesla.
BigBattery has a Rhino battery thats 14kwh. That is there version of a Tesla powerwall. Has moar capacity and cheaper! Signature Solar has some good deals on Solar Panels. If you want used solar, I got mine from Santan Solar.
So basically on Alibaba when they advertise "A" cells it actually means "it's almost the same as a real A cell". Is that enough difference to make a difference?
For the most part yes that is what I gather. Many can just about be a grade A but failed the "testing" which could have been something very minor.
I would bet there are a few that advertise A but are actual B. I personally think most of those are on aliexpress.
Would I buy from alibaba again YES. If I wanted 100% precision I would buy real grade A from SFK.
Thanks for doing this test.
I have some slightly bloated CATL 305ah cells which arived like that and i preformed the same tests as you and got almost the exact same results.
I have read quite a few peeps with bloated CATL cells and doesn't seem to be an issue?
Yeah I would 100% use them!🤘
im only seeing the Certified EV/ESS cells from SFK if its that big of a deal why are there no other tubers doing it and it cost 58-ish dollars per a cell more i haven't seen a vid to make the cost worth it to me
If you have any other cells sitting around, I’d be glad to take them off your hands. Would love to expand my battery bank🤘🏼
I dont have enough of the same cell to make a working battery unless it was 12v!🙄😆
Bummer🙁😉
😄🤘
Hi. What can you tell about Shenzhen Qishou (QSO) lifepo4 cells from Alibaba? There are some reviews but I'm in doubts. Are they worth buying?
I am pretty sure Andy from offgrid garage ordered some or had some but I dont remember the outcome. I wanna say they were ok depending on the model.
De ahí que a veces hagas pruebas y hayan resultados diferentes
Otra cosa es que se hagan pruebas a las grado B y los mejores resultados se vendan como grado A eso es otra cosa
looks like you got lucky and did get A grade alibaba's
I just bought my first lifepo4 cells, Grade B CALB 280A and there is that they need compression but not sure is it ok if i put those cells to plastic case so that they are in tight fit, like sunfunkits have.
After all, voltage is the same in all cells and no any bulging.
Yeah you can 100% put in a case for SFK or like SFK. They use foam on the sides so it does allow the cells to squeeeeeeze in there! I have there 12v kit and I had ZERO issues putting in the cells!🤘
@@AveRage_Joe Ok, any BMS suggestions?, I have heard that in some BMS balancing is not good.
Im a fan of the JBD......BUT that is really the only regular style bms I have used. A lot of people like the JK as well. I would not ise a daly.
@@niemma2ou are correct, some BMS balancers (passive 150mA) are all but useless on these cells and they need at least 2A or more active balancer, with parameters setup correctly for best results.
I use the JK BMS’s with 2A active balancing on a 24v & a 48v systems and like how well they work & balance so far, it has a nice app too, although it does tend to jam on my Iphone a bit, otherwise I love JK. JBD do have some nice BMS’s too of course, but I have had some issues with the cheaper versions I found in some cheapo 12v batteries (28 cylinderical lipo4 cells in each), when I added JK BMS’s to these batteries it fixed their badly imbalanced cells within a day & these cheap batteries are now 2 quite reasonable 24v 5kwh battery packs, not the best, but ok for the requirements.
Compression is not that big a deal, unless it is for mobile use, main thing is that it is all reasonably secure however u mount or locate ur new cells. Also agree on NOT using Daly. Hope this helps, have fun!
I recently bought some cells from Docan and the QR code reader I have on my phone said that they were manufactured in Sept. of 2024! What do you make of that?
I would say you have some futuristic batteries WAY COOL! Are the QR codes stickers or laser etched?
@@AveRage_Joe Stickers. I think they might be re-packaged used cells or, at best, lower grade cells than I paid for. Disappointed.
Hmmmmm.... is there a laser etched code under the top plastic? Where or what company did you order from?
ESS cells are basically 3rd tier used. With LSEV being above that and HSEV being above that. HSEV are still used cells still very good but more expensive. Chinas naming scheme of calling cells grade A new etc is all misleading. Every cell us diy type would purchase are all very used but cheap and are good enough. Just understand that what you buy is very used. If i am buying i am looking for LSEV. They cost more but are better than ESS and is a fair balance of life vs cost.
Between rept and eve cells which brand you prefer.
Thanks a lot....
Honestly both are great. REPT is a little cheaper. One thing I will mention tho is a lot of complete batteries like server rack batteries or others, they always use EVE. Not sure why but they do. If I didnt have a budget, Id go EVE. If your broke like me, Id go REPT🤭😆
@@AveRage_Joe thanks a lot for your help and your time 👍
Fan tester Wh results are bad because they do not have separate sensing wires, and system resistance causes a voltage lower than OCV to be used in the Wh calc.
Are you trolling? The voltages he measured where after he charged them up. 🙄
@@Foxfried Not trolling. Must have spaced out when charged. Edited.
I must have missed the original comment!💥🤘
Yeppers! Cells were tested twice then IR tested.🤘
@@AveRage_Joe Because I revised the stupid comment resulting from my lack of attention span. :)
Do you ever weigh them? I'd be curious to see if the weight and the capacity line up.
I didnt weigh the EV cells but have weighed all my others and showed it in the vids when I got them. I could check tho
Basically what you are saying is that you paid twice as much for "real grade A"' from an American supplier while only having 10 Ah more from them. Not convinced as to who scammed you.
these batterys loose the certification from the moment sunfunkits welded the poles onto the battery. Automotive cells some without terminal poles and are tested on the max amp. With these single stud poles thats not possible.
Is it possible to get a grade A cell from Alibaba if not wjat site can o buy grade A cell
Alibaba link error!
Guess if you are using that inverter for your system, and you are maxing it out, and your batteries are not sagging with the test, then you should not have a problem.
100%. I am doing a 16s tho so would need to check the others for sure🫣😄
REPT cells have strange behavior they seem balanced above 75% lower than 75% voltage difference will be much more i have cells go 100mv lower than other cells i am trying to top balance them again and test.
What bms shoyld I get for my car audio bank. I have 160Ah of spim08hp cells and I want to keep them balanced and monitor from my phone. Looking to have 16000 to 20000 watts. I'm also running 2 400A alternators. Hope you c can help me out. Thanks
Whoa NICE! So is that wattage constant or more like "burst" or surge. Thats a crap ton of power for 12v! Ill have to think on that one!
@@AveRage_Joe hoping to make that constant power.
How are BTR Power 12v-140ah assembled batteries still less expensive per wh?
I havent seen BTR yet. Are they EV grade? One difference is the amp hour rating, 140 to 280.
@AveRage Joe
Unsure what grade the cells are. And can't find much on them. Cost per watt hour isn't Amp hour dependent much.
Boom baby boom….
😆💥💥💥🤘
Taking the Wh reading and dividing it with the nominal voltage of the cell is just wrong. During a discharge (and you can pick e.g. any of Andy's curves he recorded as example) the voltage stays above 3.2V for the majority of the time (over 60% iirc). If the voltage were truly 3.2V over the entire discharge, you could do this - even if it were average at 3.2V - but because it's over 3.2V for most of the time you're getting a skewed result in favor of higher Ah results. The reason they're skewed is in the definition of nominal voltage: the nominal voltage is measured at the mid point between full charged and fully discharged based on a 0.2C discharge - so unless you discharge these particular 304Ah cells at 60A, you're not having a 3.2V nominal voltage over the curve, and you can't just divide these results by the nominal voltage.
In fact, if you take the Wh reading of your capacity test (with the ZKE) and divide that by the Ah measurement of the same test, you can see e.g. that cell 1 has an average voltage of 3.22V, etc. The whole reason of rating a battery in Ah is because it takes voltage and losses out of the equation: any bad connection, wire resistance, etc. will impact the Wh readings (especially on devices without separate voltage sense wires like that fan one), but will still produce accurate Ah readings (the current is the same everywhere in the circuit).
You are completely unhinged and should resign from your post as moderator on Diy Solar Forum.
💥🤘
Instead of don't forget ... I do remember .. I almost moved on and didn't thumb up it.
🤷♂️💥🤘
Where I can buy cv certified cell
Was CV a typo and you ment EV? If so links in description.
Let's be clear, SFK add the terminals after they receive the cells from Eve, and Eve do not approve those stud type of terminals on those cells. It might be worth contacting Eve to verify what I am suggesting here. My point is if you take a "certified automotive grade" cell and do not comply with the manufacturer's specifications, are they still automotive grade? Maybe that is just a technicality if they test the same with both terminal types? I would suggest having accurate information is a good start though.
how would you use the cells if you did not have a terminal with them? You don't make any sense...
@@Foxfried Sorry I don't make any sense to you. The answer you are looking for is a buyer/reseller would be a manufacturer, not the general public, and either laser weld the cells together, or laser weld their own terminal post, or drill and tap a hole to insert a threaded stud. I hope that helps clear things up for you.
What is a or several methods that are approved by Eve?
I learned not to buy SFK stuff in case the owner wants to leak my criminal record!
Meow!
😆🐈🤘
Over at YT'r Ray Builds Cool Stuff he is happy with Jenny Wu of Docan Power. Not to hijack your Channel Joe.
Ray is the reason I just bought my cells from Jenny Wu. I don't think I would go that route again. Previously I bought from Amy Wan who a lot of the guys on Will Prowse DIY Forum purchase from. Those cells I was very happy with. The only reason I went with Jenny Wu was because I could get them quicker. If I would have had months to wait for the cells I would have gotten them from Amy.
Missed your comment. Id have take a look and no worries
Did you test any of them yet?
@@AveRage_Joe I have not. Complicated situation. The cells were delivered in PA where our cabin with the off grid solar system is. I live in Florida!! I was in PA two weeks ago for a very short visit due to a family issue. I set forth to top balance but ran out of time. I had to return to FL and won't be back for another month. At that time I will top balance and check capacity.
@@jws3925 OK. Bottom line Jenny Wu and Amy Wan purchases are OK.
So you are comparing, automotive grade meaning high current new batteries with solar storage lower current older batteries. Not really a good test setup to compare. It is apples and pears comparing.
If you are going to roll the dice with ting-tong cells then you should at least order one or two spares and set aside the worst ones
Yes 100% should do that!!!💯💯🤘
No buldge...I am thinking that these cells have no balls...🤔
😬🤣💯%
First!
💥💥💥💥💥💥💥🤘
Why do you verbally place a decimal point .. where there shouldn't be ?
Did you buy these cells randomly from this company anonymously? If not this review is entirely pointless.
I purchased the 16 from alibaba. SFK sent the 4 EV Grade. What would make this entirely pointless. Real question btw
These are not grade B cells so this would not apply. Are you some ebay-er trying to sell stuff and SFK is making life hard? I'm reading comments now and it appears most of the people that are the most upset are people selling grade B on eBay and Amazon are angry that buyers keep asking for test reports and other stuff the grade B pawners don't have to offer.
SFK is charging a big premium for pretty much the same cells, and bit of paperwork. And when @RayBuildsCoolStuff did a capacity test on SFK, and found disappointing results, he got threatened with a lawsuit by SFK.
Any DIYer who goes for some of the known good alibaba providers, there seems little value in SFK.
🤣 Ohh you mean the guy that goes around telling people to buy docan, who has been busted with scratched off QR codes that were re-lasered? Yeah have fun with those junk grade B 304 that have been relazered with 280K counterfeit qr codes.
@@Foxfried That is new to me. Any link or info on how to get this information?
A or B or Automotive is just marketing. They all came out of the same factory. If everyone is selling the same thing, you have to differentiate yourself from the competition. Buy the cheapest and get 1 more with the money you save. Check out Ray builds cool stuff sfk battery test
That makes total sense, the manufacturer just decides to scratch off the QR code because they have a mental disability. Or Perhaps your are just blinded by your desire to save a few $... This test directly contradicts every thing Ray builds cool stuff does, as he goes around preaching reject cells are better than EV, these guys both use the same tester, why such different results?
The manufacturer doesn't scratch off the qr code. The middle man does so the cells can't be traced back to the maker
@@ciciedee5474 You realize how ridiculous you sound?
@@ciciedee5474 No the manufacturer scratches it off because it failed quality testing and or safety tests, they auction these cells off in lots.
I agree with you on the cells come from the same factory however there is a difference in A, B ect... Having said that there is a difference doesnt mean the cells wont test about the same. Grade A passed or meets the testing requirements(I dont know what those requirements are). If the cell doesnt meet those then it is automatically a grade B. Like Ive said in some of my other videos, I dont know ALL the battery things and learn stuff all the time. When I purchased the alibaba rept cells, I purchased the cheapest cells I could find!! I would 100% get an extra few cells next time to pick the best ones and have an extra if something went wrong later on!💥🤘