Just a tip from a german hobby electric pv battery junky... I figured out, its far more easy to carry the batterys around, if they are empty! With all that Watt Hours inside, they get really heavy. And if a battery is too small, I go out to North Sea and pick some more Kilo Watt from there. Its free of charge. Well. Like your work and testing, saves me a lot of time. Thanks!
you learned your lesson: now we have a 2 weeks cliff hanger I still doubt that we will see any advantages from the SFK cells and I also have not seen the yellow papers EVE ships with in case of grade A cells. At least here we had gotten these papers back then and i guess SFK had also done a video about these shipping documents.
Ill be doing a test tomorrow with 4 different brands, 4 different capacity's in a 12v battery and we may even try in a 16s! Did I hear you say that as well???💥🤘
Hi Andy, As we explained the Label is at 3.2V nominal so you take the WH/3.2v I understand you may not agree but this is how the label works. The rest of the discrepancy is due to your clamp method and running 40 amps through 10 gauge wire which is rated for 30 amps continuous. Should you decide to test with a lug and at 30 amps you will probably pick up about 20-30 WH which will translate to 1025 WH = 320 AH at 3.2v The clamp method will always result in poor readings on the ZKE. As you have seen the video by Average Joe when done properly its close to the label. But yes Calendar Aging does play into the overall rating...
I also what to clarify the video we have final word on grade B, those cells were provided from our customer so understand we did not go and try to find bad grade B cells, our analysis done because we had RMA a bms multiple times and wanted to get to the bottom of it and in THAT case 1 cell was bad 1 was the same as EV grade and 2 were OK grade. Hope that clarifies. Take care.
Nice, The difference will be seen how quickly the voltage drops after full charge... If the voltage drop is caused by leakage currents internally and these increase with time, the lifetime will suffer...
I really like this channel.. But i see one of the tests it shows the difference between grade B And A battery cells with the load of 500w for individual cell Conclusion: the cell could deliver the rated capacity for 50-100W. but if the load is between 100-600W the grade B can't stand and fail immediately.
The B-Grade cells have no problem delivering 100A without breaking in. We have tested the worst cells I have from battery #1 and pulled 3kW from the 48V battery and fully discharged it that way. No issues at all. Once the other 4 batteries are here, we will do a similar test in direct comparison between certified and storage grade batteries.
Actually they are much easier to get out when fully discharged (I speak from experience). I see that you discovered the same method that I did. They are also much easier to install when fully discharged. The SFK kit with quality EVE 304 cells and a JBD BMS makes an excellent battery that you can actually lift. I have never equaled what EVE tests, however 311AH is pretty normal. The other cell at 308AH is likely less due to calendar aging (my experience).
They were 25%SOC. I never could see a difference if charged or not. Must be far less than 1mm. Measuring capacity is never the same with too many factors influencing the result.
Yes I'm still here and still watching your videos I find it interesting thanks for showing I'm still useing my lead acid batterys but seriosly thinking of lithium any way you keep well from South Africa
Thanks Andy. To be clear, those SFK cells might have been certified automotive grade when they were purchased from Eve, but I can't see how they can still be certified when they no longer comply with the Eve's specifications. Those terminals were added after the fact and not by Eve. Eve have stated their 304Ah cells cannot be used with bolts or studs and must be laser welded together to get the full benefit of the cell specifications. The biggest capacity cells from Eve that can be used with bolts are the LF280K, and then also used with terminals that conform to their specifications as per the ones they supply. Can't comment on their specifications for their smaller capacity cells, but definitely no stud and nut combo for their 280 and 304 cells. Hope that makes sense and helps.
Hey Andy great video. I noticed on the latest SFK kit V.4 (watched on 3/10/2023) they include a cell puller that you bolt to the studs. You may still have to start them with the gravity assist method...😅
Love the videos Andy, keep up the good work. I look forward to the video where you cut the trashy alligator clips you attach to the ss post off, and then put a proper ring lug on for voltage sensing.
The clips are absolutely fine for measuring the voltage. There will be 0.00% difference if using ring lugs or clamps. Different for the current clamps, but that's not important as we measure the voltage separately.
Great stuff as usual Andy. I’m going to build a solar generator in a box soon. Just slowly gathering the components. Very nervous. Wish me luck. Maybe I get back to you in 5 months when I’ve finished lol 😂😂😂
You'll be fine. You can always go back and re-watch some of the videos here on the channel. All info is out there. Or just ask us here. But, good luck! 😂
@@OffGridGarageAustralia great Andy. Thanks for encouragement. I’ll initially make for dad then in the future hopefully build a second for myself. Keep up the good work.
I know EVE calls both LF304, but the newer cells should probably be called LF304K, if we followed the same naming convention as with the 280Ah. If you have look, the terminals on the SFK are a lot closer to the edge than the older ones (as Andy also pointed out). It seems that like with the LF280 and the LF280N, you can drill and tap the older LF304, but like with the LF280K, you can't drill and tap the newer LF304. The specs changed between the LF280 and the LF280K, but I haven't compared old LF304 spec sheets versus newer versions to see if there's a difference. I'm just mentioning that because there might be some internal differences, other than one being automotive grade and one being storage grade.
It's not just the naming convention though. There was a LF280, a LF 280N and now the LF280K, all with slightly different goop inside and also different cycle count and compression figures. I have not seen a LF304K specs sheet, they all were just LF304. Even the QR code says that. So, not sure if they have slightly different chemistry or just different terminals 🤷♂️
I've been thinking about building my own BMS; circuit board and components. One feature would be turning the BMS off both manually and automatically for storage.
@@OffGridGarageAustralia Not as one unit, but we are currently in the middle of a 32 unit 4s8p lead acid system to make our 48v. Each battery weighs 33kg. Will replace the lead acid cells with LFP cells when they die. Makes sense to use them for the time being however as we got them free. Should be about 30kwh total or 12-15kwh usable.
Ive been following your channel and few others and trying to find out what is good BMS, i live in Finland and doing my first Lifepo4 battery from 280Ah cells and it goes to van use so i would like that temp protection is reliable and seems active balance is better on BMS?. I have notice that JK and JBD is most talked about.
@@sfkenergy I only have 100 amp rated 10 gauge silicone wire . I thought you said " I'm not going to waste any more time with grade B warriors . " To which I replied " I hope you keep your word . " Leave us grade B clowns alone.
Are the LF280K cells the twin bolt version? I have them and think they are much better, the thread's are actually a helicoil, and of course there are two on each terminal.
Hi Andy, thanks for your super informative content. With your help I was able to design a capable system for our van. Keep it up... maybe not until midnight... Greetings from Sternburg Land!
Next time, try making a wooden handle with holes for longer 6 mm (or 8mm or whatever they have) bolts to attach to the battery. Pull 1 out & the rest should be easier.
This is my second test with these certified cells. Both could not deliver what was printed on the label. I'm getting 4 more form EVE directly. That will be interesting!
Could I use this box to charge my Outlander? I have no socket in the parking now, but I could move the battery to my apartment, charge it and bring it back with an 240V inverter to charge the car. The battery is now at 71% of SOH and takes in around 7kWh.
No, it's still in my box of broken parts. I had email contact with ZKE but they advised to contact the shop where I bought it. But that was just a shop on Ali with no technical knowledge.
Figures. Don’t get much support for less than $100 items anymore. Thanks for the buck booster coverage awhile back. Got a plan for cheap 12 to 24 volt helper charge on a boat from that video.
Hello all. I'm sorry that, and excuse me that I'm writing this comment too late. I afraid even nobody going to read this , already 1 year old video:( But, still, I especially read all the 137 comments here and not found anyone paid attention to a small detail which I think very interesting. I do not understand how it is possible that cells sitting in storage for a very long time (in that black battery case) where BMS showed fully rested average voltage of cells 13.06V/4 = 3.265V/cell showed state of charge only 19%. 3.265V/cell at rest is representing something about 51% SOC. Or what was set up into overkills' BMS app as reference points 10%,20%, etc ? Initially when app is opened it was showing 28%, then after discharge and charge off, it "resets" showing SOC by "reference points" by voltage. But anyway. Especially paid attention on charged in capacity after chargint test, it showed 229.6 Ah charged into cell current. Which represents ( 307 full measured capacity minus 229.6 = 77.4ah and 77.4ah is actually 25.2% initial SOC. BMS was showing 28% calculated and then 19% estimated by voltage; where as we seen after re-charging real was 25.2% :) but , still, according to estimating by voltage at rest it should be about 50%. So why and where is the reality ? Or that "estimated by voltage at rest table" is not correct ? But I checked many times in practice it was proven that it is correct. At rest 3.2V represents 20% SoC, 3.25V - 40%, 3.265V - 50%, 3.275V - 60%, 2.8V - 5%, etc.
Hi Andy, love the videos, but you have not made the one I’m waiting for 😢. I would love to see the second Multiplus II being installed and configured. But when???
That's still a bit ahead. I'm waiting for the sparky to figure something out. At the moment, I don't really need that much power, but once the house is connected, yes a second on in parallel will go in.
I'd like to know how you identify Eve cells (particularly the 304Ah)? I bought some that have octagonal terminal bases, but most I've seen have round ones with pointy ends (a bit like a rounded diamond). Mine are supposedly A-Grade Eve (aren't they all?). Also how much bulging is acceptable? 2 of my 4 have bulging that makes a 2mm and 1.5mm space against a straight edge. Is that ok, or should I ask for replacements?
The octagonal terminals show the version 3 of the cells from EVE. Latest and greatest apparently, but not different to the other ones... You need to scann the QR code on the top of the battery to encode the data. There is a LFP Scanner for Android available. Linked on my website here, aprox. half way down: off-grid-garage.com/batteries/
@@OffGridGarageAustralia Ah thanks. That's very reassuring. Yes the QR codes scan and are correct, but I assumed they could be fakes. (you weren't the seller by chance as they came from Rockhampton?) Love the videos - very helpful.
@@wfdTamar No, I'm not in Rocky and I'm not selling anything... I wouldn't be too concerned about the swelling. It's pretty normal with our 'A-Grade' batteries.
@@OffGridGarageAustralia A regular on the DIY Solar forum are saying there are no 304’s with octagonal bases, only v.3 280k. Have you actually seen Eve 304 with octagonal base?
Andy, please take some thermal shrinking PVC and cover metal plug of the Battery Internal Resistance Tester. Watching it "naked" over batteries is heartbreaking. Maybe you are ok with it, but well over 60k people watching you and they can make serious mistake and injury themselves. Please :)
@@OffGridGarageAustraliaIt is all Bull💩 smoke and mirrors. Has anyone ever got them??? I tryed grade certified EVE grade A from a UK supplier,. Nothing was provided, when they tested under capacity and I requested them I got the run around. The threads were oversize and sloppy, and no certs so they got sent back and a full refund given. Their etched grade B are brilliant! Cheers Andy
Can you give the link for the QR reader. My EVE cells will be here morrow directly from EVE. I can do the test bcz I bought a tester I can send you the graph if you would like to compare the results.
Yes and the clamp method along with running 40 amps on 10 gauge cable will also loose about 3-4 amp hr because 10 guage wire is rated for 30 amp continuous and the clamp is not a good contact with the cell, it should be a lug (in our opinion but we respect that Andy has been using the bus bar/clamp method for all his previous testing so he is trying to be consistent). However, then 1 should not expect to meet our results.
Just a calculation, not real capacity though. No loses on the cables as the voltage is measured directly at the terminals without voltage drop. It does not matter how good or bad the tester cables are connected with separate voltage sense cables.
Just would let the community know that received batch of 280Ah cells from Shenzhen Qishou Technology and started testing them. First out of 16 cells is below promised 280Ah. I know many people favor this supplier but apparently there seems to be "quality variation" and as we know - price is well above other suppliers. So be careful out there and dont fall for it only based on only Andy's webpage - you can receive crappy cells also from this supplier.
@@OffGridGarageAustralia Thanks for noticing the post. I had 3 request for them while ordering, a) each sell must have +280Ah b) No swelling on cells c) Must be newer than 9/22 batch. This was confirmed by Amy. Batch was delivered from EU (poland) stock. Delivered first (tested) cell had very small date sticker on it stating 12/2022. Tested with 30A in range of 2.5...3.65V with 14A cutoff on charge. Test done with calibrated zketech ebc-a40l but now while noticing this I will perform discharge test with more precise RIGOL DL3031A electronic load. Obviously I need to now quickly perform test to all cells even my plans was just to trust the product and make a few samples to the 16 batch. Lets see how this goes, however testing will now take a lot of time as I cannot run tests during night due to noise of the tester :P Not very happy although.
@@OffGridGarageAustralia Alright, 3/18 tested and results appear to be pretty much the same, non exceeding 280Ah even measured with more precise load. Interesting is that these cells according to barcode is quite fresh cells from end of 2022. Did some load pulse tests to one of the cells which was fully charged and with 60A load the voltage drop on cell was around into 3.14 volts and dropping quite fast. With such (small) load current, voltage should definitely not drop into 3.14 and likely with 120A that would mean well below 3 Volts. So eventually cell with below half juice on it with bit higher load currents could potentially hit BMS low voltage protection on. Would be interesting to see more hard load tests on the channel but equipment for such tests are quite expensive. Not to test BMS but actually the cells. There is some pretty good tests on youtube although, driving example 500W on factory new cell where there is actually not much drop on the voltage. There is a difference on these battery cells. B grade is B grade but a lot of variation inside of this "B" also.
@@OffGridGarageAustralia no I’m not joking.. I found a studie from a German university. Battery electrolyte decay in aging 18650 cells.. most of the electrolyte sinks to the bottom of the cel coursed bij the difference of mass of the components and cousin harm in the top of the cells.. and Ofcorse the normal decline. But it plays a role.. kind of logical, any liquid that exists out of multiple components separate if you put it on a shelf for 15 years .. yes Do you have fb i have a copy
@@OffGridGarageAustralia that’s wye I also think that you can apply this for those prismatic cells.. maybe placing them vertically Is a good idea . The components stay closer together .. the study is called. Inhomogeneous distribution of lithium and electrolyte in aged lit-ion cylindrical cells .. look closely to page 11
I have a question. I am designing a small bench top 16.8V Lipo battery. Purely for a silent DC audio power source. The idea is a 4S 2P 18650 pack with all the bells and whistles that I want to play with. Including a custom charge/discharge/protection and BMS circuit. This morning I am trying to calculate the balance requirements. V1 will be passive balance only. This is not an energy harvesting device but will be charged from a solar battery, I'm not worried with losing 10% while charging due to balance current. Now am I concerned with loosing up to 10% at MAX amperage. Ideally not at 10% amperage though :) Numbers.. a 4S2P 6Ah pack, under going a 0.2C charge is 1.2A, or 600mA per parallel cell. 600mA*4.2V is 2.57W. 2.57W inbound current to the cell. A 10R resistor across that 4.2V cell will only drop 1.75W (and get pretty toasty). The issue is, if the charger continues to push the same current across the pack that cell WILL over--volt. The balance resistor cannot pull it down hard enough. In small chargers (and in my case) this is solved by basing your CV value not on the pack voltage (target 16.8V), but on the highest cell voltage (4.2V). In this scenario, when the cell, with the balance resistor across it already hits 4.2V, then the 2.57W input power will cause it to become >4.2V immediately triggering a drop of the total pack charge current, following a standard integral(?). If the pack is very imbalanced, the charge current will reduce to the point where it is 1.75W per cell such that the fully charged cells can "shed" the entire charge current through their resistors. There are devils in the details, but as most of it is software in my case, I'm not that concerned. The question is... when you get up to the scale of Andy's garage, where you have completely different charger versus, balancer, versus load control? Is this why you guys get all obcessed with active balancing during charging, because if a single cell over-voltage occurs for you, the charge terminates immediately until you address it by manually (or some other management way to lower the charge current and continue)? I actually bought an active balance board years ago for a 3S lipo. I could never understand how it was expected to work. To me it seemed like it could only charge through it's balance leads. Anytime I gave it more power it just charged the pack and tripped an overvolt. Maybe I understand why now. It is assuming the balancer has no direct control over the charger, it just actively tries to help moving power between cells, up to 1A in my case, WHILE the charger is pushing current across the whole pack at the same time. Push too much, the balance current can't cope, DISCONNECT. Thankfully, for this bench pack I can combine the CC/CV charger with the balancer.
@@oliviervanespen5047 In the end I just bought a small JK_BMS. I figured by the time I messed around I'd have spent the £30 anyway. Also bought 6 14Ah LFP cells. I can centre tap the pack to get + 0 - power rails for amplifiers too :)
Just a tip from a german hobby electric pv battery junky... I figured out, its far more easy to carry the batterys around, if they are empty! With all that Watt Hours inside, they get really heavy. And if a battery is too small, I go out to North Sea and pick some more Kilo Watt from there. Its free of charge.
Well. Like your work and testing, saves me a lot of time. Thanks!
I like the pan and tilt webcam idea. Remotely monitor whether the garage is on fire. 😀
It will go on the roof for everyone to watch the solar panels.
Batteries Batteries Batteries ... Thanks Andy!
There will be more!
It 6 deg (c) in Rainy Michigan USA.... Your rainy day looks a lot better!
At least it is still warm and... 12A is not too bad...
Thanks Andy
you learned your lesson: now we have a 2 weeks cliff hanger
I still doubt that we will see any advantages from the SFK cells and I also have not seen the yellow papers EVE ships with in case of grade A cells.
At least here we had gotten these papers back then and i guess SFK had also done a video about these shipping documents.
Ill be doing a test tomorrow with 4 different brands, 4 different capacity's in a 12v battery and we may even try in a 16s! Did I hear you say that as well???💥🤘
2:20 Look perfectly balanced! 😁 The AB is not going to drain the batteries it adds max 100-200ma/drain per day.
Hi Andy,
As we explained the Label is at 3.2V nominal so you take the WH/3.2v I understand you may not agree but this is how the label works. The rest of the discrepancy is due to your clamp method and running 40 amps through 10 gauge wire which is rated for 30 amps continuous.
Should you decide to test with a lug and at 30 amps you will probably pick up about 20-30 WH which will translate to 1025 WH = 320 AH at 3.2v
The clamp method will always result in poor readings on the ZKE. As you have seen the video by Average Joe when done properly its close to the label.
But yes Calendar Aging does play into the overall rating...
I also what to clarify the video we have final word on grade B, those cells were provided from our customer so understand we did not go and try to find bad grade B cells, our analysis done because we had RMA a bms multiple times and wanted to get to the bottom of it and in THAT case 1 cell was bad 1 was the same as EV grade and 2 were OK grade. Hope that clarifies.
Take care.
"Thou Doth Protest Too Much!".
Nice, The difference will be seen how quickly the voltage drops after full charge...
If the voltage drop is caused by leakage currents internally and these increase with time, the lifetime will suffer...
I really like this channel.. But i see one of the tests it shows the difference between grade B And A battery cells with the load of 500w for individual cell
Conclusion: the cell could deliver the rated capacity for 50-100W. but if the load is between 100-600W the grade B can't stand and fail immediately.
The B-Grade cells have no problem delivering 100A without breaking in. We have tested the worst cells I have from battery #1 and pulled 3kW from the 48V battery and fully discharged it that way. No issues at all.
Once the other 4 batteries are here, we will do a similar test in direct comparison between certified and storage grade batteries.
Actually they are much easier to get out when fully discharged (I speak from experience). I see that you discovered the same method that I did. They are also much easier to install when fully discharged. The SFK kit with quality EVE 304 cells and a JBD BMS makes an excellent battery that you can actually lift. I have never equaled what EVE tests, however 311AH is pretty normal. The other cell at 308AH is likely less due to calendar aging (my experience).
They were 25%SOC. I never could see a difference if charged or not. Must be far less than 1mm.
Measuring capacity is never the same with too many factors influencing the result.
Yes I'm still here and still watching your videos I find it interesting thanks for showing I'm still useing my lead acid batterys but seriosly thinking of lithium any way you keep well from South Africa
HA! Good old gravity to do the work for you. Nice job. Thanks for sharing
Thanks Andy. To be clear, those SFK cells might have been certified automotive grade when they were purchased from Eve, but I can't see how they can still be certified when they no longer comply with the Eve's specifications. Those terminals were added after the fact and not by Eve. Eve have stated their 304Ah cells cannot be used with bolts or studs and must be laser welded together to get the full benefit of the cell specifications. The biggest capacity cells from Eve that can be used with bolts are the LF280K, and then also used with terminals that conform to their specifications as per the ones they supply. Can't comment on their specifications for their smaller capacity cells, but definitely no stud and nut combo for their 280 and 304 cells. Hope that makes sense and helps.
Hey Andy great video. I noticed on the latest SFK kit V.4 (watched on 3/10/2023) they include a cell puller that you bolt to the studs. You may still have to start them with the gravity assist method...😅
I would not pull on the terminals! They were really tight in this case.
Love the videos Andy, keep up the good work. I look forward to the video where you cut the trashy alligator clips you attach to the ss post off, and then put a proper ring lug on for voltage sensing.
The clips are absolutely fine for measuring the voltage. There will be 0.00% difference if using ring lugs or clamps. Different for the current clamps, but that's not important as we measure the voltage separately.
Long videos, Short videos all the same.all gut. When I am busy in the shop, your videos are playing in the background
Nice, put them on a loop and let them play. Thanks!
Hi Andy and all folks. Why aren’t CALB 280 or 304 out there? Only 230ah and more expensive than EVE and CATL
Finally, another interesting video. Good stuff! :)
More to come!
Great stuff as usual Andy. I’m going to build a solar generator in a box soon. Just slowly gathering the components. Very nervous. Wish me luck. Maybe I get back to you in 5 months when I’ve finished lol 😂😂😂
You'll be fine. You can always go back and re-watch some of the videos here on the channel. All info is out there. Or just ask us here.
But, good luck! 😂
@@OffGridGarageAustralia great Andy. Thanks for encouragement. I’ll initially make for dad then in the future hopefully build a second for myself. Keep up the good work.
I know EVE calls both LF304, but the newer cells should probably be called LF304K, if we followed the same naming convention as with the 280Ah.
If you have look, the terminals on the SFK are a lot closer to the edge than the older ones (as Andy also pointed out). It seems that like with the LF280 and the LF280N, you can drill and tap the older LF304, but like with the LF280K, you can't drill and tap the newer LF304.
The specs changed between the LF280 and the LF280K, but I haven't compared old LF304 spec sheets versus newer versions to see if there's a difference. I'm just mentioning that because there might be some internal differences, other than one being automotive grade and one being storage grade.
It's not just the naming convention though. There was a LF280, a LF 280N and now the LF280K, all with slightly different goop inside and also different cycle count and compression figures.
I have not seen a LF304K specs sheet, they all were just LF304. Even the QR code says that. So, not sure if they have slightly different chemistry or just different terminals 🤷♂️
I would love to have this very nice SFK kit to build a LiFePo4 battery for my sailboat.
If you're in Australia, I'll send it to you.
@@OffGridGarageAustralia that’s a pity. I live in The Netherlands 🥴
@@OffGridGarageAustralia What are the costs to send it to The Netherlands?
The weather is shitty here in Northwest Ohio as well Andy I feel ur pain.
You Are just like Andy, allwsys complaining over the whether.
Why Don't you do somthing about it? 😝
Central Ohio checking in
There is no bad weather, just not enough light out there! 12A outside is not bad!
You need a Bollerwagen for your batteries.
I have a crane now!
I've been thinking about building my own BMS; circuit board and components. One feature would be turning the BMS off both manually and automatically for storage.
Heya, that's a nice test and all fits the bill
Weather = Minus SPAT
Is this inspired by AveRage Joe's recent comparison between Alibaba and SFK's cells? I noticed your comment there. Thx. The more testing the better.
I had my test already done when he published his video. More test coming soon.
Wow that sunfunkit looks super portable 😂😂😂
Have you lifted a 48V battery? The SFK battery IS portable 😂
@@OffGridGarageAustralia Not as one unit, but we are currently in the middle of a 32 unit 4s8p lead acid system to make our 48v. Each battery weighs 33kg. Will replace the lead acid cells with LFP cells when they die. Makes sense to use them for the time being however as we got them free. Should be about 30kwh total or 12-15kwh usable.
As always, we'll done!
Ive been following your channel and few others and trying to find out what is good BMS, i live in Finland and doing my first Lifepo4 battery from 280Ah cells and it goes to van use so i would like that temp protection is reliable and seems active balance is better on BMS?.
I have notice that JK and JBD is most talked about.
Moikka! Both the JK and JBD are good, but I prefer the JK myself.
Get the JK-BMS!
Nice to see you using the clamps and 40 amps of current . Someone will be along soon to complain about it . That sell out Joe cut his off . :>)
Maybe you can send Andy some of your 140 Amp rated 10 gauge wire.
@@sfkenergy I only have 100 amp rated 10 gauge silicone wire . I thought you said " I'm not going to waste any more time with grade B warriors . " To which I replied " I hope you keep your word . " Leave us grade B clowns alone.
Hope you are well my friend. Way too long between beers.
Are the LF280K cells the twin bolt version? I have them and think they are much better, the thread's are actually a helicoil, and of course there are two on each terminal.
The ones I will get are the twin bolt genuine EVE LF280K, untouched, not welded and certified.
Hi Andy, thanks for your super informative content. With your help I was able to design a capable system for our van. Keep it up... maybe not until midnight... Greetings from Sternburg Land!
Thank you for your feedback. Stay charged!
I'm tuning in for sunshineeeee! Where is it??
Exactly! 🤷♂️
I wonder how you have done so the led in your battery bank change color with the soc? I have search but can´t find anything.
It's not SOC related. It changes colour randomly.
Che software usare per collegare il SUNN-1000G2 via wifi al PC? Grazie
Next time, try making a wooden handle with holes for longer 6 mm (or 8mm or whatever they have) bolts to attach to the battery. Pull 1 out & the rest should be easier.
You are not the first one, who could not reproduce the SFK values.
This is my second test with these certified cells. Both could not deliver what was printed on the label. I'm getting 4 more form EVE directly. That will be interesting!
More proof to buy the cheapest cells. Someday when I get rich, I will buy 100cells. Even 10$ a cell can make a difference.
Yeah, I think so too. Never had any problems with the other cells, even some of them never met the specified capacity.
Yeah🎉
Could I use this box to charge my Outlander? I have no socket in the parking now, but I could move the battery to my apartment, charge it and bring it back with an 240V inverter to charge the car. The battery is now at 71% of SOH and takes in around 7kWh.
You're doing better than me, currently have a range of around 20~ 25km (mostly closer to 20) @ 103K Not good !
4kWh it can deliver, so you would need to charge at least 2 times to fill the Outlander.
This reminds me, did you have any luck further repairing the smaller ZKE-20 tester?You called them for a board as I remember.
No, it's still in my box of broken parts. I had email contact with ZKE but they advised to contact the shop where I bought it. But that was just a shop on Ali with no technical knowledge.
Figures. Don’t get much support for less than $100 items anymore. Thanks for the buck booster coverage awhile back. Got a plan for cheap 12 to 24 volt helper charge on a boat from that video.
Hello all. I'm sorry that, and excuse me that I'm writing this comment too late. I afraid even nobody going to read this , already 1 year old video:( But, still, I especially read all the 137 comments here and not found anyone paid attention to a small detail which I think very interesting. I do not understand how it is possible that cells sitting in storage for a very long time (in that black battery case) where BMS showed fully rested average voltage of cells 13.06V/4 = 3.265V/cell showed state of charge only 19%. 3.265V/cell at rest is representing something about 51% SOC. Or what was set up into overkills' BMS app as reference points 10%,20%, etc ? Initially when app is opened it was showing 28%, then after discharge and charge off, it "resets" showing SOC by "reference points" by voltage. But anyway. Especially paid attention on charged in capacity after chargint test, it showed 229.6 Ah charged into cell current. Which represents ( 307 full measured capacity minus 229.6 = 77.4ah and 77.4ah is actually 25.2% initial SOC. BMS was showing 28% calculated and then 19% estimated by voltage; where as we seen after re-charging real was 25.2% :) but , still, according to estimating by voltage at rest it should be about 50%. So why and where is the reality ? Or that "estimated by voltage at rest table" is not correct ? But I checked many times in practice it was proven that it is correct. At rest 3.2V represents 20% SoC, 3.25V - 40%, 3.265V - 50%, 3.275V - 60%, 2.8V - 5%, etc.
Hi Andy, love the videos, but you have not made the one I’m waiting for 😢. I would love to see the second Multiplus II being installed and configured. But when???
That's still a bit ahead. I'm waiting for the sparky to figure something out. At the moment, I don't really need that much power, but once the house is connected, yes a second on in parallel will go in.
I'd like to know how you identify Eve cells (particularly the 304Ah)? I bought some that have octagonal terminal bases, but most I've seen have round ones with pointy ends (a bit like a rounded diamond). Mine are supposedly A-Grade Eve (aren't they all?).
Also how much bulging is acceptable? 2 of my 4 have bulging that makes a 2mm and 1.5mm space against a straight edge. Is that ok, or should I ask for replacements?
The octagonal terminals show the version 3 of the cells from EVE. Latest and greatest apparently, but not different to the other ones...
You need to scann the QR code on the top of the battery to encode the data. There is a LFP Scanner for Android available. Linked on my website here, aprox. half way down: off-grid-garage.com/batteries/
@@OffGridGarageAustralia Ah thanks. That's very reassuring. Yes the QR codes scan and are correct, but I assumed they could be fakes. (you weren't the seller by chance as they came from Rockhampton?) Love the videos - very helpful.
@@wfdTamar No, I'm not in Rocky and I'm not selling anything...
I wouldn't be too concerned about the swelling. It's pretty normal with our 'A-Grade' batteries.
@@OffGridGarageAustralia
A regular on the DIY Solar forum are saying there are no 304’s with octagonal bases, only v.3 280k.
Have you actually seen Eve 304 with octagonal base?
Andy, please take some thermal shrinking PVC and cover metal plug of the Battery Internal Resistance Tester. Watching it "naked" over batteries is heartbreaking. Maybe you are ok with it, but well over 60k people watching you and they can make serious mistake and injury themselves. Please :)
👍👍👍
Can you actually get a copy of the EVE Certificate? As in physical documented wet stamped proof?
I would not know how. And how do we proof the authenticity if it is not emailed from EVE directly to me? Everything else is just a copy.
@@OffGridGarageAustraliaIt is all Bull💩 smoke and mirrors.
Has anyone ever got them???
I tryed grade certified EVE grade A from a UK supplier,. Nothing was provided, when they tested under capacity and I requested them I got the run around. The threads were oversize and sloppy, and no certs so they got sent back and a full refund given.
Their etched grade B are brilliant!
Cheers Andy
Can you mix 2 cells of 304 with 2 cells of 280k to make a 12v system if you just have those? Or should they be exactly same?
Yes, that can be done. After top balancing, you can use 280Ah of this 12V battery. Two cells will be empty by then, two still have some capacity left.
@@OffGridGarageAustralia thanks mate.
Can you give the link for the QR reader. My EVE cells will be here morrow directly from EVE. I can do the test bcz I bought a tester I can send you the graph if you would like to compare the results.
Sure, link is on my website (about half way down): off-grid-garage.com/batteries/
are these batteries made by Qso or Eve?
Andy how can I afford cells like those that was in the sfk case you took out ?
They get 320 by dividing Wh by 3.2. so 1008/3.2 = 315Ah
Yes and the clamp method along with running 40 amps on 10 gauge cable will also loose about 3-4 amp hr because 10 guage wire is rated for 30 amp continuous and the clamp is not a good contact with the cell, it should be a lug (in our opinion but we respect that Andy has been using the bus bar/clamp method for all his previous testing so he is trying to be consistent). However, then 1 should not expect to meet our results.
Just a calculation, not real capacity though.
No loses on the cables as the voltage is measured directly at the terminals without voltage drop. It does not matter how good or bad the tester cables are connected with separate voltage sense cables.
Just would let the community know that received batch of 280Ah cells from Shenzhen Qishou Technology and started testing them. First out of 16 cells is below promised 280Ah. I know many people favor this supplier but apparently there seems to be "quality variation" and as we know - price is well above other suppliers.
So be careful out there and dont fall for it only based on only Andy's webpage - you can receive crappy cells also from this supplier.
Thanks for sharing. Did you confirm the capacity with them before ordering? Also, how did you test, C-rate, temperature, cut-off...?
@@OffGridGarageAustralia Thanks for noticing the post. I had 3 request for them while ordering, a) each sell must have +280Ah b) No swelling on cells c) Must be newer than 9/22 batch. This was confirmed by Amy. Batch was delivered from EU (poland) stock.
Delivered first (tested) cell had very small date sticker on it stating 12/2022. Tested with 30A in range of 2.5...3.65V with 14A cutoff on charge.
Test done with calibrated zketech ebc-a40l but now while noticing this I will perform discharge test with more precise RIGOL DL3031A electronic load.
Obviously I need to now quickly perform test to all cells even my plans was just to trust the product and make a few samples to the 16 batch. Lets see how this goes, however testing will now take a lot of time as I cannot run tests during night due to noise of the tester :P
Not very happy although.
@@OffGridGarageAustralia Alright, 3/18 tested and results appear to be pretty much the same, non exceeding 280Ah even measured with more precise load. Interesting is that these cells according to barcode is quite fresh cells from end of 2022. Did some load pulse tests to one of the cells which was fully charged and with 60A load the voltage drop on cell was around into 3.14 volts and dropping quite fast. With such (small) load current, voltage should definitely not drop into 3.14 and likely with 120A that would mean well below 3 Volts. So eventually cell with below half juice on it with bit higher load currents could potentially hit BMS low voltage protection on.
Would be interesting to see more hard load tests on the channel but equipment for such tests are quite expensive. Not to test BMS but actually the cells. There is some pretty good tests on youtube although, driving example 500W on factory new cell where there is actually not much drop on the voltage. There is a difference on these battery cells. B grade is B grade but a lot of variation inside of this "B" also.
Like# 5
Shaking up the battery electrolyte is going to expand the battery life time. So say a German university.
Oh, wow, never heard of that before. Another theory. Wait until people building little vibrators which shake the battery from time to time.
@@OffGridGarageAustralia no I’m not joking.. I found a studie from a German university. Battery electrolyte decay in aging 18650 cells.. most of the electrolyte sinks to the bottom of the cel coursed bij the difference of mass of the components and cousin harm in the top of the cells.. and Ofcorse the normal decline. But it plays a role.. kind of logical, any liquid that exists out of multiple components separate if you put it on a shelf for 15 years .. yes Do you have fb i have a copy
@@OffGridGarageAustralia that’s wye I also think that you can apply this for those prismatic cells.. maybe placing them vertically Is a good idea . The components stay closer together .. the study is called. Inhomogeneous distribution of lithium and electrolyte in aged lit-ion cylindrical cells .. look closely to page 11
@@OffGridGarageAustralia and if you take it seriously,, that cell comprising serves also multiple things.. 🤔💭
hi voltage battery 4 hi voltage inverters ? fronius gen 24 & huawei hybrid ? 😮
💙👊😎
Just for the Algorithmus und mächtig viel Spaß und Mehrwert sicher nicht nur für mich.
Many thanks, Thomas.
Lol, I have the same Sricam PTZ
They are everywhere. We will use it for one of the next projects to give us a live view on the solar roof.
I have a question. I am designing a small bench top 16.8V Lipo battery. Purely for a silent DC audio power source.
The idea is a 4S 2P 18650 pack with all the bells and whistles that I want to play with. Including a custom charge/discharge/protection and BMS circuit.
This morning I am trying to calculate the balance requirements. V1 will be passive balance only. This is not an energy harvesting device but will be charged from a solar battery, I'm not worried with losing 10% while charging due to balance current. Now am I concerned with loosing up to 10% at MAX amperage. Ideally not at 10% amperage though :)
Numbers.. a 4S2P 6Ah pack, under going a 0.2C charge is 1.2A, or 600mA per parallel cell. 600mA*4.2V is 2.57W.
2.57W inbound current to the cell. A 10R resistor across that 4.2V cell will only drop 1.75W (and get pretty toasty).
The issue is, if the charger continues to push the same current across the pack that cell WILL over--volt. The balance resistor cannot pull it down hard enough.
In small chargers (and in my case) this is solved by basing your CV value not on the pack voltage (target 16.8V), but on the highest cell voltage (4.2V).
In this scenario, when the cell, with the balance resistor across it already hits 4.2V, then the 2.57W input power will cause it to become >4.2V immediately triggering a drop of the total pack charge current, following a standard integral(?).
If the pack is very imbalanced, the charge current will reduce to the point where it is 1.75W per cell such that the fully charged cells can "shed" the entire charge current through their resistors. There are devils in the details, but as most of it is software in my case, I'm not that concerned.
The question is... when you get up to the scale of Andy's garage, where you have completely different charger versus, balancer, versus load control?
Is this why you guys get all obcessed with active balancing during charging, because if a single cell over-voltage occurs for you, the charge terminates immediately until you address it by manually (or some other management way to lower the charge current and continue)?
I actually bought an active balance board years ago for a 3S lipo. I could never understand how it was expected to work. To me it seemed like it could only charge through it's balance leads. Anytime I gave it more power it just charged the pack and tripped an overvolt. Maybe I understand why now. It is assuming the balancer has no direct control over the charger, it just actively tries to help moving power between cells, up to 1A in my case, WHILE the charger is pushing current across the whole pack at the same time. Push too much, the balance current can't cope, DISCONNECT.
Thankfully, for this bench pack I can combine the CC/CV charger with the balancer.
Maybe consider a RC type lipo pack and balance charger, I have bought a Yuki charger(300w) for less than 50Euro
@@oliviervanespen5047 In the end I just bought a small JK_BMS. I figured by the time I messed around I'd have spent the £30 anyway.
Also bought 6 14Ah LFP cells.
I can centre tap the pack to get + 0 - power rails for amplifiers too :)
Should of charged & discharged the second sfk brand new one also,...
I did. Same result, 312Ah.
Soggy cool Australia
I had a shirt on, so it was cooler than the days before...
These balancers can kill your battery . That's for sure!
🐸🐸🐸
SFK is just buying the same cells we can buy, QA'ing them and sticking stickers on them, maybe thats worth something to you.
I don't think they test the cells , just have the supplier put their label on .
First one ;)
First?
Nope, missed it by 10 seconds! ☹
These guys... 🤦♂️