diy solar

diy solar

32 280Ah Eve "grade a" from Shenzhen Luyuan (Amy Wan)

I will repeat what I said when I quoted Basen: "K has 6000 cycles, but it is based on 0.5C discharge, and N has 3500" Where in there did you get me (or Basen) saying an N was 6K?
Well .... I guess the part in the thread above that I highlighted where you said .... The cycle life of K and N is actually the same.

They aren't. The K is redesigned and the dimensions of the cell is different than the N.... just because the K's are spec'd at a .5C rate and are sped'd at 6000 cycles.... doesn't mean the N will have 6000 cycles if you run it at .5C

I'm kind of at a loss why you don't understand what I'm saying.
 
Well .... I guess the part in the thread above that I highlighted where you said .... The cycle life of K and N is actually the same.

They aren't. The K is redesigned and the dimensions of the cell is different than the N.... just because the K's are spec'd at a .5C rate and are sped'd at 6000 cycles.... doesn't mean the N will have 6000 cycles if you run it at .5C

I'm kind of at a loss why you don't understand what I'm saying.
Not getting involved in your argument...I just want to make a point based on my opinion.

I don't think cycles listed by manufacturers is a huge deal. It's fairly clear people will get at least 2000 cycles from LFE cells with no compression and if the cells are run through a full cycle every day then the cell would last better than 5 years, and at that time capacity would be around 80%.

If we order a hydraulic test jig from EVE so we can keep the cells at perfect compression through the SOC like EVE is able to do, then the K cell should last 6000 cycles. That equates to better than 16 years of useful life if the cells are run through a full cycle every day.

In any case the cells will most likely start to age before 80% capacity is reached. Let's not forget most don't run through full cycles every day and thus are keeping the cells between the knees which extends cycle life.

When I saw the spec sheet for the K cell I was impressed with the 6000 cycle life claim at first. Not so much any more....lol. I would like to see more data from EVE to substantiate their 6000 cycles claim. 3500 cycles using perfect compression is easier to believe.
 
Not getting involved in your argument...I just want to make a point based on my opinion.

I don't think cycles listed by manufacturers is a huge deal. It's fairly clear people will get at least 2000 cycles from LFE cells with no compression and if the cells are run through a full cycle every day then the cell would last better than 5 years, and at that time capacity would be around 80%.

If we order a hydraulic test jig from EVE so we can keep the cells at perfect compression through the SOC like EVE is able to do, then the K cell should last 6000 cycles. That equates to better than 16 years of useful life if the cells are run through a full cycle every day.

In any case the cells will most likely start to age before 80% capacity is reached. Let's not forget most don't run through full cycles every day and thus are keeping the cells between the knees which extends cycle life.

When I saw the spec sheet for the K cell I was impressed with the 6000 cycle life claim at first. Not so much any more....lol. I would like to see more data from EVE to substantiate their 6000 cycles claim. 3500 cycles using perfect compression is easier to believe.
I we are using them in a mobile environment .... we are even less likely to get their optimum cycle life .... especially if they aren't in a conditioned space.
Temperature has a huge influence as well and none of us will likely run them under perfect conditions. .... but, all we have to go by is the spec .... and trying to understand what the spec is saying helps us get the most we can out of these cells.
 
Well .... I guess the part in the thread above that I highlighted where you said .... The cycle life of K and N is actually the same.

They aren't. The K is redesigned and the dimensions of the cell is different than the N.... just because the K's are spec'd at a .5C rate and are sped'd at 6000 cycles.... doesn't mean the N will have 6000 cycles if you run it at .5C

I'm kind of at a loss why you don't understand what I'm saying.
And I am at a loss that you can't comprehend it wasn't me saying that. That was Basen. How many times do I have to repeat that to get you to stop quoting me when it wasn't my quote. I have not ever said they were the same. Quit saying that I did.
 
Actually MrPhoton hasn't gotten his cells yet .... His post is based on serial numbers on a spreadsheet ...We do know that Amy has posted on that thread and told him she will make it right if he gets different type cells.
It was clear from Amy's reply to Mr. Photon that she doesn't even know what he is talking about when it comes to N vs. (), i.e. 66 vs. 71. Even when she tried to say she matches by amperage, the implication was that EVE mixed 66s and 71s. Further, if a vendor sends you different models as a matched set, and you have to return and reship batteries, that is a lot of delay for something trying to build a pack. Like in my case, I paid more to get domestic batteries and hopefully not get involved in a return.
 
And I am at a loss that you can't comprehend it wasn't me saying that. That was Basen. How many times do I have to repeat that to get you to stop quoting me when it wasn't my quote. I have not ever said they were the same. Quit saying that I did.
But you did repeat that as if it were fact ..... and interpreting the spec sheets in such a way as to come to that conclusion is flawed.
I don't think there is much we are going to agree on regarding Amy or the K Vs N cycle life .... Hope you have good luck with the ones you are getting from Basen.

I REALLY do hope we can vet another trusted provider .... as many as possible actually.
 
But you did repeat that as if it were fact ..... and interpreting the spec sheets in such a way as to come to that conclusion is flawed.
If they say 3500 cycles at 1C at 25c and the other says 6000 at .5c at 25c, I don't know how I can come to an incorrect conclusion. EVE product specs compared to EVE product specs. I am not reaching a conclusion, just repeating what I read which was what Basen said.
I don't think there is much we are going to agree on regarding Amy or the K Vs N cycle life .... Hope you have good luck with the ones you are getting from Basen.

I REALLY do hope we can vet another trusted provider .... as many as possible actually.
As I have said, I am a parrot in most cases as I don't have the experience with batteries and solar that most people here do.

I think any "issues" I have had with Basen are more about ignorance on the part of the salesperson. I think she honestly thought her inventory was 2021 production and won't accept the fact that they are old stock.

Comparing my single experience with Basen, I received quality packing, perfect condition batteries, great communication, the complete EVE spreadsheet, and delivery in a week and a price cheaper than Luyuan from China. If Luyuan is the gold standard, I think Basen is as good or better. If I didn't mention it, Basen said they would take the whole shipment back if I was unhappy! Oh ya, Emily/Basen's English was been the best of any vendor I have dealt with in China.

I think the lesson with any vendor is to get as much clarity as possible as English isn't English and it is obvious the salespeople are ignorant about what they are selling, at least at some level.
 
As I have said, I am a parrot in most cases as I don't have the experience with batteries and solar that most people here do.

I think any "issues" I have had with Basen are more about ignorance on the part of the sales person. I think she honestly thought her inventory was 2021 production and won't accept the fact that they are old stock.

Comparing my single experience with Basen, I received quality packing, perfect condition batteries, great communication, the complete EVE spreadsheet, and delivery in a week and a price cheaper than Luyuan from China. If Luyuan is the gold standard, I think Basen is as good or better. If I didn't mention it, Basen said they would take the whole shipment back if I was unhappy! Oh ya, Emily/Basen's English was been the best of any vendor I have dealt with in China.

I think the lesson with any vendor is to get as much clarity as possible as English isn't English and it is obvious the salespeople are ignorant about what they are selling, at least at some level.
That good to hear ..... especially the US stock part. Do you know if you had to return them if the return would also be a US location. ..... I only ask that because I saw someone else post that that happened to them.

Please keep documenting your experience with Basen.
 
Do you have to pay shipping back? I also wonder if the shipment has to be declared as Battery/hazardous materiel and other requirement for shipment.
I had good experience with Gloria Lou of BASEN for the order I made last year on my first purchase from Alibaba, she sent me the replacement (LISHEN 270Ah) within 10 days for one of the shipping damaged cell..
The second set of batteries, REPT 280Ah, I bought are from Exliporc due to price and some of good test result from other people in the forum, so I took a chance and very happy with REPT cells as well.
May be I am just lucky with my purchase.
 
Do you have to pay shipping back? I also wonder if the shipment has to be declared as Battery/hazardous materiel and other requirement for shipment.

Yes, that is a UN requirement, encouraged by the USA after a shipment of batteries caught fire and caused a passenger plane to crash with no survivors (Miami, crashed in the everglades). That UN certificate is actually a "do not ship on passenger planes" notice. The US law is even more strict.
 
Top balancing

This kinda deserves a good post on its own:

When I received the cells, as mentioned in the OP, they all tested to 3.295/.296. But, I got antsy and wanted to start playing around. I hooked up 1 string of 16s to my inverter, charged some, discharged some, didn't have bus bars torqued down well, and un-balnced that string from the other 16. Would not advice, but end of the day not a big deal.

Here is how I top balanced these cells:

1.) I made custom busbars for the 2p16s setup. Doing this with a handdrill was a 1/10 experience, could not NOT recommend enough. I actually ordered a drill press so I can come back and finish rounding out some of these holes a little bit as the fit is somewhat tight on the terminals. <please don't make fun of my lopsided holes on a few. This took way too many hours to do and kinda sorta figure out>

View attachment 47461

2.) I hooked up the cells on a 2p16s config, slapped on the trusted Renogy 48/3500 (Seriously the product is not *that* bad Will ;), and it has a marked grounded spot for the AC out that you missed in the video)
3.) Charged them like this for @25A until 1 cell (set) hit ~3.3
3a.) Note: the 16s bms can't reach them in straight line, and I have yet to cut the bus bars to make this a proper rectangle, so I did the oblong ending so I didn't have to mill anything else until my press gets here.
3b.) I should have let them go all the way to 3.6 on 1 cell. I jumped the gun because "cell" was creeping out higher than the rest. This could have been due to non-copper busbar connecting them (see below), or maybe not. Idk i am not an EE.
4.) The 16th cell group (on the Red positive) hit high voltage

View attachment 47462
5.) I took the cells and split them (poorly) into 2 sets of 16 again, with "cells" 1-8 now being 1-16 on string 1, and 9-16 being 1-16 on string 2.
6.) I series charged string 1 more, while starting to parallel charge string 2 @ 3.65V
6a.) The 10A/30V charger would only sink like 4A of current (prob because voltage was close-ish). After literally 48 hours the cell voltage just hadn't changed a meaningful number.
7.) While String 2 was in the forever parallel balancing act on the slow charger, I manually tried to balance some of String 1 (the series string) by adding resistors to the high cells, led light sinks etc.
7a.) This actually worked quite well. I got this string to hit HV disconnect around with them all being pretty close.
7b.) Parallel'ing was still going slower than life
8.) Swapped the string series (1) into parallel, and parallel (2) into series
9.) Parallel charged string 1. This was making slow but noticable progress from ~3.4 to 3.63 over a few days
10.) Did Step 7 with string 2 to manaually balance while in series. I also used boost charged some cells as needed to help speed this along
11.) String 2 *back* to parallel. Step 9 with string 2 now. This only took ~12-18 hours to get to ~3.63
12.) Re-trickled string 1 to be very close to string 2 voltage
13.) parallel connected String 1 and 2 now into 1 giant 32P battery lol. I put on the 3.65 and let it charge for another day or so until the current sunk to ~0.2A, and the voltage across the entire battery was 3.621

14.) Let them rest for a few hours, then re-set them up as in step 4 (but used copper bars on the main negative, main positive). Hooked them up to the inverter and let the capacity test begin. The cells were really locked in voltage (imo) all the way down. Never got more than ~.007 apart

Fun facts. I did make sparks only once, and thankfully that was when messing with the parallel pack @3.5V or so. And boy did it rain sparks for a few seconds (I tried to connect 2 sets of 4 backwards (P --> N and N-->P)


Overall this took probably 5-6 days to fully do. Could have been ~2-3 if I knew what I was doing, and had enough trust in what I was doing to let the charging happen overnight the first few nights (I was too worried about un-intentional overvoltage, so I disconnected when I couldnt monitor)


Thanks for coming to my tedtalks
Are you concerned at all about long term corrosion between the copper bus bars and aluminum terminals? I'm also using copper but eventually want to get around to tinning the leads. I'm curious about what others are doing.
 
Are you concerned at all about long term corrosion between the copper bus bars and aluminum terminals? I'm also using copper but eventually want to get around to tinning the leads. I'm curious about what others are doing.
I'm using copper bus bars with noalox right now ... no problems yet.

I'm planning on making some tinned ones ... but will still use noalox.
 
That good to hear ..... especially the US stock part. Do you know if you had to return them if the return would also be a US location. ..... I only ask that because I saw someone else post that that happened to them.

Please keep documenting your experience with Basen.
I asked about returning to EVE in the US and they didn't answer. They do want me to pay shipping back if I want to swap the single cell. They didn't ask for $ to ship the whole order back.
 
I asked about returning to EVE in the US and they didn't answer. They do want me to pay shipping back if I want to swap the single cell. They didn't ask for $ to ship the whole order back.
Hmmmm .. Usually no answer means the answer you didn't want to hear. I'd press them on that til I got an answer and knew what the cost would be to ship it back.
 
Hmmmm .. Usually no answer means the answer you didn't want to hear. I'd press them on that til I got an answer and knew what the cost would be to ship it back.
Basen at this point is focused on the date issue. I keep insisting the cells are a year old and they say they aren't. I told them I would go straight to EVE for an answer, but EVE hasn't replied. Since EVE is "transparent" on their spec sheets on how to interpret the dates, it would seem they would be open to telling us the production dates per type of battery. Mr.Proton was also trying to get the EVE "auditor" to respond regarding the date codes and last I heard he hadn't received an answer either.

If we can believe the spreadsheet from Basen, it clearly shows a June 2021 shipment date for the LF280s I received. Don't think Mr.Proton was provided the same info from Luyuan, but unless Luyuan is shipping batteries they got over a year ago, they too received LF280s this year.

Not knowing how EVE works, could a vendor ask for "old stock" and get them, or is EVE selling LF280s as new stock?
 
Are you concerned at all about long term corrosion between the copper bus bars and aluminum terminals? I'm also using copper but eventually want to get around to tinning the leads. I'm curious about what others are doing.
not really. Maybe next year i'll re-do the busbars and get them tapped a little better/more evenly and tin them, but if an corrosion starts to build ill just take them off and re-polish for now.
 
Hard to keep track of all of the threads here with overlapping content. To get this particular thread updated, let me recap.
1. Seems Basen and Luyuan were ignorant regarding all of the details of what they were selling. This is how I received LF280 vs. N and Mr. Proton getting (or will be receiving) mixed 66 and 71s.
2. Obviously some English translation issues, i.e. the difference between purchase date and manufacturing date.
3. Both Basen and Luyuan seem to have purchased directly from EVE "matched" cells, that criteria still not defined other than similar Ah.
4. The batteries both of them received seemed to have been made in December. Basen's order was placed ahead of Luyuan's order so they had theirs in June and had some of them stateside in early August.
5. The Basen batteries I received have QR codes, perfect physical condition, and ideal packaging. Am load testing a cell now which would be the only other question regarding a battery made in December.
6. Basen provided the full EVE data sheet similar to what Luyuan offers with the cells.

This is a combination of information in these threads regarding the Luyuan orders and my personal Basen order experience. I can also say that my dealing with Luyuan was also pleasant as it has been with Basen other than product ignorance.

Best wishes to all and keep charged as Andy would say!
 
Yes, that is a UN requirement, encouraged by the USA after a shipment of batteries caught fire and caused a passenger plane to crash with no survivors (Miami, crashed in the everglades). That UN certificate is actually a "do not ship on passenger planes" notice. The US law is even more strict.
Just as a point of fact, you are conflating two different crashes, here. The infamous Everglades crash was caused by oxygen concentrators, not batteries. I cannot find any report of battery fires causing an Everglades plane crash.
 
Just as a point of fact, you are conflating two different crashes, here. The infamous Everglades crash was caused by oxygen concentrators, not batteries. I cannot find any report of battery fires causing an Everglades plane crash.
You are correct:

They are still banned by international agreement from being shipped as cargo on passenger planes.
 
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