Maybe u can see if u can get the case with some minor modifications to accommodate the Batrium? The original guy paid Seplos a design fee to have them come up with the case, you could perhaps do the same (were you so inclined) to have it customized?
Our NEW GO-TO LiFePO4 vendor...09.20.21
- Thread starter ghostwriter66
- Start date
I wanted to do an update on my purchase so as not to be labeled "hit and run." I went out of town for Christmas the day after receiving my slightly bloated cells and I've been too busy (and discouraged) to follow up. The cells have been sitting in compression for over three months now. They improved, but it's more of an evening out of the overall thickness. Docan initially sounded like they were going to help me out, but never came through. I'm willing to accept that I had an unusual experience, but I bought these four cells to see if building my own batteries was something I wanted to do before buying a bunch more. I was envisioning receiving 48 slightly bloated cells and being stuck with that, and decided DIY batteries wasn't worth the headache anymore. I bought some server rack batteries today.
The four bloaty bois are going in this little portable battery that I've channeled my inner Ray to construct, and I suppose they'll be fine for that. I'll make a post specifically about it once I wrap it up.
The four bloaty bois are going in this little portable battery that I've channeled my inner Ray to construct, and I suppose they'll be fine for that. I'll make a post specifically about it once I wrap it up.
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Ampster
Renewable Energy Hobbyist
Try some compression on them and I am sure they will work fine. Have you run a capacity test on them?
His post says they've been under compression for 3 months
@taser1984 What an unfortunate experience. Did Docan send you a picture of the cells before they shipped?
This is why we should have the vendors on the forum, so they can be publicly made to answer for such things. Now everyone is just left trying to resolve the experiences individually, and that apparently doesn't work
I didn't get a picture before they shipped. I don't know if they sent them bloated or they don't like the altitude here (6000 ft) or if something else happened. I haven't capacity tested them because of an issue I had with the battery testers I bought. I have no reason to believe they won't achieve full capacity though, and even if they don't, what am I going to do about it? I may still run the capacity test out of curiosity, but it will take several days to get results.
Taser, I received a Docan 4-pack of slightly smaller EVE 230Ah cells a couple of weeks ago, to my home (altitude 5200 ft). They arrived, as expected, at relatively low state-of-charge, barely 3.26V per cell. No "bloat" was present when mine arrived. In order to remove the bloat, you will probably need to pull them down about that far, and then re-assemble your pack - with comression already applied (before bringing them way back up to re-do your capacity test, if you desire to do that).
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Although you said that they've been under compression for 3 months, you didn't describe the amount of compression which you applied. These EVE cells are large, and EVE's own testing (IIRC) was done at around 16 PSI. Less than 12 PSI doesn't do much good. So your target, as described in the long and very detailed Thread on the subject of 'compression with springs' (here), is the surface are of the big face time that pressure factor. For the case of my smaller cells, that result is about 610 pounds. Your bigger ones need around 660 lbs.
I suspect that your pressure of 'compression' was not high enough. Can you confirm or deny that to have been the case? Either way, if you try to compress them again (preferably within a spring-loaded structure) you should probably pull them down to around 3.26 volts per cell (about 35% SOC) before re-assembling your pack.
Horsefly
Solar Wizard
A couple of thoughts here.
- I suspect that once the cells are bloated, you can't "un-bloat" them. I would think that applying enough compression to cause the bloat to go down can't be good for the cells.
- Although I'm not sure (I think I've read it here from others) that bloating is caused almost always by either or both high C charging and/or over-charging.
- I'm currently building my 4th battery. Two 8S and two 4S, all built at over 5,000 ft elevation (I'm in Denver). I do capacity tests on all of them but always charging and discharging at around 0.1C to 0.2C. I've not seen any cells bloat yet. My two 8S batteries are also going to have loads and charge sources all less than 0.4C.
- Although I've read all the arguments for compressing cells, I'm not sold on the idea. I put a tiny bit of compression on my batteries just to keep them from moving around. I do think that a compression fixture may extend the life of cells that are routinely exposed to high C rates. That's the primary customer for the cell manufacturers. I think those of us doing solar will seldom have high rates, so I don't think the compression is needed. Conversely, I think it would be easy to over-compress and damage the cells.
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@rickst29 I think you are correct. I had them compressed with 36" Quick Grip clamps between plywood pieces. They can generate around 300 lbs of clamping force, according to my bathroom scale, and the cells are 8"x7" so we're talking 5-6 psi. The cells arrived the day before I was supposed to go out of town, then the day I was supposed to leave we had a freak power outage. I used the cells to power my fridge and freezer for that day, so SOC was quite low. As soon as the power came back I put the cells in my cargo trailer so they wouldn't burn my house down and we took off.
I'm with @Horsefly in that I don't think you can "fix" a bloated cell and I was frankly a little scared to try. I am a little curious now about how they would act with 12-15 psi and I may experiment with that later if I can figure out a way to reliably measure the forces involved. No guidance was given by Docan as to how to go about any of this, so I basically went with as much compression as I could reasonably manage and felt safe with given what tools were immediately available since I was so busy at the time.
It is comforting to hear that altitude is likely not the cause.
I'm with @Horsefly in that I don't think you can "fix" a bloated cell and I was frankly a little scared to try. I am a little curious now about how they would act with 12-15 psi and I may experiment with that later if I can figure out a way to reliably measure the forces involved. No guidance was given by Docan as to how to go about any of this, so I basically went with as much compression as I could reasonably manage and felt safe with given what tools were immediately available since I was so busy at the time.
It is comforting to hear that altitude is likely not the cause.
Horsefly
Solar Wizard
Getting back on topic...
I labeled all the cells, scanned the QR codes, and did the obligatory voltage test. I then started doing capacity tests, but so far have only gotten through 4 cells, which have all been above the spec 160Ah.
Pretty amazing that it was one week from when I placed the order on Alibaba to having the cells sitting on my dining room table. My most recent previous purchase was from Amy Wu @ Luyuan. Those cells were also in perfect condition, but it was 113 maddening days from when I placed the order until they arrived.
As others have pointed out, the bus bars are not too impressive. They are two thin (~1mm) tinned copper "bars" held together with heat shrink. Can't really call them bars when they are that thin. Doesn't impact me as I will either use some of the other bus bars I have or make some more out of 1/8" (~3mm) solid copper.
- 20-Mar (Sunday) - Via an email (sent 10pm MDT), I requested a quote from Jenny Wu @ Docan. She responded almost immediately.
- 22-Mar (Tuesday) - I placed an order for 8 Eve 160Ah cells. Cost was $92 each, plus a 5% fee for using PayPal.
- 25-Mar (Friday) - Jenny gave me the UPS tracking numbers for two boxes
- 29-Mar (Tuesday) - The two boxes were received.
I labeled all the cells, scanned the QR codes, and did the obligatory voltage test. I then started doing capacity tests
| Cell # | QR Code | Mfg Date | V @ Rcvd | Capacity | Ch / Disch Rate |
| 1 | 04QCB74721000JB860005013 | 6-Aug-2021 | 3.295 | 162.5Ah | 25A/25A |
| 2 | 04QCB74721900JB8J0000778 | 18-Aug-2021 | 3.294 | 160.5Ah | 30A/30A |
| 3 | 04QCB74721800JB8H0001236 | 17-Aug-2021 | 3.294 | 160.4Ah | 30A/30A |
| 4 | 04QCB74721500JB8E0003621 | 14-Aug-2021 | 3.295 | 161.2Ah | 25A/25A |
| 5 | 04QCB74721400JB8D0004937 | 13-Aug-2021 | 3.295 | 163.7Ah | 25A/25A |
| 6 | 04QCB74721800JB8H0001234 | 17-Aug-2021 | 3.295 | 160.6Ah | 25A/25A |
| 7 | 04QCB74720600JB7Y0001840 | 30-Jul-2021 | 3.295 | 162.7Ah | 25A/25A |
| 8 | 04QCB74720600JB7Y0005302 | 30-Jul-2021 | 3.295 | 163.3Ah | 25A/25A |
Pretty amazing that it was one week from when I placed the order on Alibaba to having the cells sitting on my dining room table. My most recent previous purchase was from Amy Wu @ Luyuan. Those cells were also in perfect condition, but it was 113 maddening days from when I placed the order until they arrived.
As others have pointed out, the bus bars are not too impressive. They are two thin (~1mm) tinned copper "bars" held together with heat shrink. Can't really call them bars when they are that thin. Doesn't impact me as I will either use some of the other bus bars I have or make some more out of 1/8" (~3mm) solid copper.
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Horsefly
Solar Wizard
By the way, in case anyone needs to get ahold of Jenny Wu here's her email address: jennywu896@gmail.com
I highly recommend Jenny and Docan.
I highly recommend Jenny and Docan.
Horsefly
Solar Wizard
I finished doing the capacity tests on my 8 160Ah cells, and updated the table two posts prior to this one. All cells exceeded the 160Ah spec. Then I top balanced them, and now I'm building a box for them.
Horsefly
Solar Wizard
I assume you are talking to me?
My cells (Eve 160Ah) were $92 per cell, plus 5% for PayPal. Is that what you are asking?
Austan
New Member
- Joined
- Jul 23, 2020
- Messages
- 45
Looks like the Docan site is down, or gone rather? All I am getting is 502 error. I swear I just looked at batteries there a couple days ago. Anyone else having this error?
www.docanpower.com
DOCAN POWER
Delivering Outstanding Capacity And Nobility Power & Trustworthy Partner for Solar LiFePO4 BatteriesDocan is TOP10 battery and battery suppliers in China. We supply TOP1 service of Lifepo4 Prismatic Cell and Battery Pack for variouse area, 12 years+ focus on high capacity, high wattage, high...
www.docanpower.com
luckielab
New Member
- Joined
- Nov 26, 2020
- Messages
- 91
I'm getting it today as well.Looks like the Docan site is down, or gone rather? All I am getting is 502 error. I swear I just looked at batteries there a couple days ago. Anyone else having this error?
DOCAN POWER
Delivering Outstanding Capacity And Nobility Power & Trustworthy Partner for Solar LiFePO4 BatteriesDocan is TOP10 battery and battery suppliers in China. We supply TOP1 service of Lifepo4 Prismatic Cell and Battery Pack for variouse area, 12 years+ focus on high capacity, high wattage, high...
Horsefly
Solar Wizard
Aliexpress? Are you sure? I'm not too sure about that. Docan uses Alibaba, and I just bought from them a couple of weeks ago with PayPal on Alibaba, and it worked fine.
