Horsefly
Solar Wizard
TL;DR - I made my second purchase from Jenny Wu of Docan, and I'm very happy with the purchase. I still highly recommend Docan and Jenny.
On the morning of Tuesday, 25-Jun, I contacted Jenny Wu from Docan to get a quote for 8 230Ah cells. She replied almost immediately with a quote for $108 per cell from the USA warehouse. After a bit more email exchanges to confirm details, I paid on Alibaba with a credit card. Using the credit card led to an extra ~5% fee from Alibaba, but I wanted the protections that come with a credit card payment. The order was placed and paid by 7:18am on Tuesday.
The two packages (4 cells each) were shipped from the warehouse in Houston around 4pm on Thursday, 27-Jun. They were scheduled for delivery on Monday, 31-Jun, but actually were delivered on the evening of Sunday, 30-Jun. At around 7pm the FedEx truck pulled up to the end of our driveway, and I saw the driver trying to balance the two 40 lb boxes in his arms. I quickly ran down the driveway to take one of the boxes from him. It would have been a shame if one or both boxes slammed into my driveway, failing in the last 70 ft of the trip.
The two boxes were packed well, and Fedex didn’t do much damage along the way from Houston to Denver. The boxes were heavy cardboard, and packing tape covered every inch. Inside, the four cells per box were encased in the same polyethylene forms that all the vendors seem to use now.
I will say that the bus bars Docan continues to provide (same as my last purchase) are not very good. Each bar is made up of two ~0.7mm thick bars, so the total thickness is about 1.4-1.5mm. The bars are plated copper (nickel, I would assume) and 20mm thick. In the past I've made and plated my own bus bars, so I may again this time.
Unpacked the cells were pristine, with no dents, scratches or bulges. Interestingly, there also was no Docan stickers - or any other stickers - on the cells. Although I don’t think it means anything, I did check and all the cells measured 3.293V or 3.294V with my Fluke. I labeled the cells 1 through 8, and scanned the data matrix codes on each. Just to pique the interest of the trolls
, I checked all the codes against the Ezeal test result spreadsheet that had been posted earlier in the forum, and I found all eight to be in there.
I blew the dust off my trusted Zketech EBC-A40L cell tester. I soon found out that the USB interface to the tester was no longer supported under Windows 11, so I had to use one of the Windows 10 machines I have in the house. Running the tests at 30A, I’m doing a multistep test on each cell: charging up to 3.65V until the tail current drops off, wait 2 minutes, then discharge at 30 amps until 2.5V. Each test is taking about 13.5 hours to run. We’re leaving for a long weekend before I can test them all, but here’s the results (and data matrix codes) so far:
I'll finish the testing next week. Although I don't expect any to fail spec capacity of 230Ah, I promise I will post a follow up if some of them don't.
In summary, I’m very happy with these cells. At $108 per cell (a bit under $114 with credit card fee), I can’t imagine getting better cells from one of the other sources, much less delivered in less than a week.
This is the second order I’ve done with Jenny Wu from Docan, and if I need more cells, I would contact Jenny first. I don't know if it is widely available, but if anyone wants her contact info let me know via PM. (I'm assuming I am not supposed to post it here)
On the morning of Tuesday, 25-Jun, I contacted Jenny Wu from Docan to get a quote for 8 230Ah cells. She replied almost immediately with a quote for $108 per cell from the USA warehouse. After a bit more email exchanges to confirm details, I paid on Alibaba with a credit card. Using the credit card led to an extra ~5% fee from Alibaba, but I wanted the protections that come with a credit card payment. The order was placed and paid by 7:18am on Tuesday.
The two packages (4 cells each) were shipped from the warehouse in Houston around 4pm on Thursday, 27-Jun. They were scheduled for delivery on Monday, 31-Jun, but actually were delivered on the evening of Sunday, 30-Jun. At around 7pm the FedEx truck pulled up to the end of our driveway, and I saw the driver trying to balance the two 40 lb boxes in his arms. I quickly ran down the driveway to take one of the boxes from him. It would have been a shame if one or both boxes slammed into my driveway, failing in the last 70 ft of the trip.
The two boxes were packed well, and Fedex didn’t do much damage along the way from Houston to Denver. The boxes were heavy cardboard, and packing tape covered every inch. Inside, the four cells per box were encased in the same polyethylene forms that all the vendors seem to use now.
I will say that the bus bars Docan continues to provide (same as my last purchase) are not very good. Each bar is made up of two ~0.7mm thick bars, so the total thickness is about 1.4-1.5mm. The bars are plated copper (nickel, I would assume) and 20mm thick. In the past I've made and plated my own bus bars, so I may again this time.
Unpacked the cells were pristine, with no dents, scratches or bulges. Interestingly, there also was no Docan stickers - or any other stickers - on the cells. Although I don’t think it means anything, I did check and all the cells measured 3.293V or 3.294V with my Fluke. I labeled the cells 1 through 8, and scanned the data matrix codes on each. Just to pique the interest of the trolls
, I checked all the codes against the Ezeal test result spreadsheet that had been posted earlier in the forum, and I found all eight to be in there.I blew the dust off my trusted Zketech EBC-A40L cell tester. I soon found out that the USB interface to the tester was no longer supported under Windows 11, so I had to use one of the Windows 10 machines I have in the house. Running the tests at 30A, I’m doing a multistep test on each cell: charging up to 3.65V until the tail current drops off, wait 2 minutes, then discharge at 30 amps until 2.5V. Each test is taking about 13.5 hours to run. We’re leaving for a long weekend before I can test them all, but here’s the results (and data matrix codes) so far:
I'll finish the testing next week. Although I don't expect any to fail spec capacity of 230Ah, I promise I will post a follow up if some of them don't.
In summary, I’m very happy with these cells. At $108 per cell (a bit under $114 with credit card fee), I can’t imagine getting better cells from one of the other sources, much less delivered in less than a week.
This is the second order I’ve done with Jenny Wu from Docan, and if I need more cells, I would contact Jenny first. I don't know if it is widely available, but if anyone wants her contact info let me know via PM. (I'm assuming I am not supposed to post it here)
