diy solar

diy solar

New Supplier for 280Ah cells: Shenzen Basen

So this thread has gone way over my head to the point it hurts. What is the consensus on these nicer busbars I expect to receive with my batteries? If I double them up will they be fine to use with my 5kw inverter? It will be a rare day that I ever pull more than 125 amps continuous.

I doubled up the bus bars I received from Shenzhen Basen and pulled 220 amps and charged at 120 amps. I had maybe a 10F temperature rise. It's far more important to make sure the tops of the cells are clean and that the bars are properly torqued down.
 
I doubled up the bus bars I received from Shenzhen Basen and pulled 220 amps and charged at 120 amps. I had maybe a 10F temperature rise. It's far more important to make sure the tops of the cells are clean and that the bars are properly torqued down.
Great to hear. Thanks. Hopefully they send me double bars as requested.
 
I requested double busbars from Basen, but did not receive them, so now it's either Aliexpress or DIY.
 
I am just making an order from this cells and other equipment from Shenzhen to Hamburg.
I will use CIS-Logistics.de
They offer 40 €/ton or m³ for Shenzhen to Hamburg and 240 € /ton or m³ from Hamburg to me near Salzburg.
Anybody interested in reducing transportation costs by using the same transport?
 
Hello Honuz,

I have run three capacity tests and have pulled 272ah's from the pack. The second capacity test yielded greater than 280ah's while the first and third yielded 272ah's...so I am going with that and I am satisfied. I did not use a resistor. I bought a cheap 1000 watt sine wave inverter. Between a small 250 watt heater, my TV, tablet and laptop I am pulling an average of 15 amps from the pack.. My build is messy and I need to get to cleaning it up....lol But everything looks good so far.
could you clarify on how these capacity tests are done ? from my lead acid days, a 200ah @ 10hr battery would be 200ah while drawing 20amps and last 10hrs, same battery would be say 170ah if drawing 50amps, 120ah, if perhaps drawing 90amps etc, so please clarify on how a correct capacity test is done on lifepo4
 
Ordered 12 cells on october 5th, still no trackable.. Poland shipper printed the UPSlabel but did nog receive the cells yet..
Hope they will arrive eventually..
 
could you clarify on how these capacity tests are done ? from my lead acid days, a 200ah @ 10hr battery would be 200ah while drawing 20amps and last 10hrs, same battery would be say 170ah if drawing 50amps, 120ah, if perhaps drawing 90amps etc, so please clarify on how a correct capacity test is done on lifepo4
The manufacturers test them using 1C rates and full cycles. A cycle is when the cell is fully charged to 3.65 volts then discharged to 2.50 volts. Basically most manufacturers will give a 2000 cycle rating. After 2000 cycles the cell will have 80% capacity remaining. You may look at the spec sheets for more on this. I will attach an EVE spec sheet.

For the DIY there are several ways of testing and they all accomplish the same thing providing one is using a reasonably accurate meter. As you know I stated I am using a cheap 1000 watt inverter. I get my ah ratings from the BMS and my DROK meter. And the Riden will show me the ah's that have been put into the cells when charging.

There are testers for testing individual cells and Will has a good video that explains capacity testing using one of those testers.
 

Attachments

  • EVE LF280N-72174  Specification.pdf
    682 KB · Views: 18
Ordered 12 cells on october 5th, still no trackable.. Poland shipper printed the UPSlabel but did nog receive the cells yet..
Hope they will arrive eventually..
You are in Poland? That doesn't give me much hope. I'm in Missouri and mine shipped on 10-18. I've heard nothing since then.
 
You are in Poland? That doesn't give me much hope. I'm in Missouri and mine shipped on 10-18. I've heard nothing since then.
I'm in the Netherlands, but the parcel goes to Poland by train, should become trackable from there, and continu to Holland
 
could you clarify on how these capacity tests are done ? from my lead acid days, a 200ah @ 10hr battery would be 200ah while drawing 20amps and last 10hrs, same battery would be say 170ah if drawing 50amps, 120ah, if perhaps drawing 90amps etc, so please clarify on how a correct capacity test is done on lifepo4
LiFePO4 testing is pretty straightforward. A 280Ah setup should be tested to the voltages that @Gazoo stated. It's how many amps for how many hours. Depending on your power draw capabilities, you can test them at any current level.
280A for 1 hour
140A for 2 hours
70A for 4 hours
40A for 7 hours
20A for 14 hours
These all calculate out to the same value.
It is best to test a little above what your real world usage will be.
 
I requested double busbars from Basen, but did not receive them, so now it's either Aliexpress or DIY.
All of the orders received by the guys that bought from Basen through my group buy have received the double bus bars as promised.
 
I'm in the Netherlands, but the parcel goes to Poland by train, should become trackable from there, and continu to Holland

I hope it won't take as long as mine from Xuba..

Shipped aug 26th, UPS tracking wasn't working untill nov 6th. Appearantly, Polish customs had huge delays (at least, thats what's been told). Once UPS had received it finally it only took 5 more days to reach the Netherlands.
 
I did some searching and sent out a Request For Quote on Alibaba looking for a different supplier for 280Ah cells.
I read all about Amy and Xuba. Even with all the guidance, some people still seem to have troubles. Their prices weren't the best, so I ordered my first 4 from UNIS. They work great, but, for some reason, I couldn't get them to send me a new label to replace one that was peeled back in shipping.
Emily from Shenzhen Basen answered my RFQ with an offer of $77.40 per cell. MOQ = 4. She says they are Grade A new cells.
Shipping is $268.00. With the Alibaba service fee, a batch of 16 came up to $1536.53 delivered to my door via FedEx (after they get off the ship).
I ordered two sets of 16.
Now, we wait...
Has anyone done a slow or fast capacity test to verify the 280ah? It doesn't look that much bigger than a 100ah. Am I missing something? how is this possible for grade A? That's like $550 with shipping for a 5kwh battery, I don't think its possible.
 
Last edited:
I have done a slow capacity test. I used a PowerLab6 and the test was repeatable. I only did several cells but i was satisfied with the consistency that I did not feel the need to do every cell. The shipping price per cell goes down with volume. Anything under $120 per kWh is a good deal in my mind. There are probably several explanations about how that is possible.
 
Last edited:
I did some searching and sent out a Request For Quote on Alibaba looking for a different supplier for 280Ah cells.
I read all about Amy and Xuba. Even with all the guidance, some people still seem to have troubles. Their prices weren't the best, so I ordered my first 4 from UNIS. They work great, but, for some reason, I couldn't get them to send me a new label to replace one that was peeled back in shipping.
Emily from Shenzhen Basen answered my RFQ with an offer of $77.40 per cell. MOQ = 4. She says they are Grade A new cells.
Shipping is $268.00. With the Alibaba service fee, a batch of 16 came up to $1536.53 delivered to my door via FedEx (after they get off the ship).
I ordered two sets of 16.
Now, we wait...
Shipping to US in my state is 131.00 dollars I guess I'll order my first 4 280ah cells from there shenzhen basin
 
Has anyone done a slow or fast capacity test to verify the 280ah? It doesn't look that much bigger than a 100ah. Am I missing something? how is this possible for grade A? That's like $550 with shipping for a 5kwh battery, I don't think its possible.
Aliexpress first 105ah I find :
130x36x200 = 936cm3 -> 0.112ah per cm3

Eve
174x72x205 = 2570cm3 -> 0.109ah per cm3

You see...the 280ah got a lower energy density then the 105ah.. if my numbers are good.
 
Has anyone done a slow or fast capacity test to verify the 280ah? It doesn't look that much bigger than a 100ah. Am I missing something? how is this possible for grade A? That's like $550 with shipping for a 5kwh battery, I don't think its possible.
Yes, I have done a discharge test on a 4-cell pack using my datalogger. I used currents from 40A to 90A. The 280Ah number is definitely real.
 
Has anyone done a slow or fast capacity test to verify the 280ah? It doesn't look that much bigger than a 100ah. Am I missing something? how is this possible for grade A? That's like $550 with shipping for a 5kwh battery, I don't think its possible.
Many have bought these cells from the suppliers that offer them. I tested the cells I bought from the group buy and was able to get 272ah's out of my 8S pack. Whether or not the cells are grade A is debatable. My guess is they are a little better than B+. One of the suppliers gave them a grade A-5 rating, whatever that means. The cells are still a great value.

One needs to keep in mind these are not capacity matched cells. If I measured the capacity of the individual cells my average would be a little more than 272ah's. I have one cell that is weaker than the others and if I felt the need to replace it I would probably get a few more ah's. Most keep their packs well between between the knees, or use around 80%. Since my pack is for power outages I plan to keep them at 70% or less capacity to help prevent degradation from storing at a high SOC.

I am not quite sure where you are getting 5kwh from. A 280ah 24 volt pack will net 7.168 kWh's. Since I am netting 272ah's the kwh's of my pack is
6.963kwh's. I am happy with that...I have a pack that is 97% capacity.
 
Back
Top