Ordered 8 EVE "new" 280Ah cells from Shenzhen Luyuan

Pyrofx

Flux capacitor builder
Im here to tell you . The trucks are coming out all night long. And BNSF is also giving anyone that will come into the yard on Saturday or Saturday a 50 dollar discount on load charge.

This is one of those cases of read what you want , but every other day I drop of and pick up a train. 250 containers in . 350 out.

About 15 itrains n a 24 hour period.

Greg
 

Stepandwolf

Solar Addict
Further research indicates that under normal conditions, trucks cannot pick up containers past business hours. They are now planning to allow trucks in the yards 24/7. But, experts say that this is a 'nothingburger' due to the fact that there is no place to deliver the containers in the middle of the night, so it's unlikely many trucks will pick up after hours anyway. :(
Wonder how many are local deliveries vs. long haul? And if they are just hauling them to the railyard, they might be open..
 

Solar Steve

Solar Enthusiast
Well, it took a very long time, but I finally received my 8 "new" 280 Ah EVE cells from Amy at Shenzhen Luyuan. All cells arrived well packed and in excellent mechanical shape, I will now start top balancing and putting together a battery for capacity testing. I am very happy with the company, Amy always gave me a good response in 24 hours or less to any of my questions. If I decide to order more I will start here, they are worth the premium.

Timeline for my shipment was as follows:

Payment cleared with Shenzhen Lyuyan: 7/9/21
Order sent out by Amy, she also sent me pictures of the shipment and a summary of the cell properties: 7/17/21
Received by FedEx in California and tracking number active: 10/11/21
Delivery to my door: 10/15/21

I'm sure the extra shipping time has to do with the current long backlog at the ports.

The only thing I'd like to see improved is a change to the studs welded onto the terminals; as many others have mentioned they really cut down on the contact area. Anyone have comments on how best to deal with this? I'm thinking of adding some aluminum washers with a tight tolerance clearance hole, this will at least get me full available contact to the stud while allowing slotted busbars that can tolerate a bit of misalignment, but of course this adds yet another metal to metal interface.
 

Steve_S

Offgrid Cabineer, N.E. Ontario, Canada
Do not use washers or such, you want direct contact to the terminal with the busbars. Try to not use more than One Ring Terminal on the cells, so if you have a BMS & an external Balancer for instance it's best to not have each wired to separate ring terminals. People do it, it works but sometimes it can create problems.
 

Just John

Photon Sorcerer
Do not use washers or such, you want direct contact to the terminal with the busbars. Try to not use more than One Ring Terminal on the cells, so if you have a BMS & an external Balancer for instance it's best to not have each wired to separate ring terminals. People do it, it works but sometimes it can create problems.
I agree it is best to combine into a single ring terminal for any extra connections. I found this the hard way. Yes, you can get multiple to work, but it is best to combine.
 

RayfromTX

Solar Addict
I don't see the contact area as an issue. I believe the resistance in what is essentially zero distance to be minimal if you have good contact, use a conductive paste and use adequate torque. There are limits to what is an adequate surface area but I think any heat created by this joint will be quickly dissipated and in the end when it comes to conductors our primary concern is heat build up, is it not? I am a proponent of using a separate tapped connection to join the BMS sensing wire to the bus bar to allow the torque of the bus bar nuts to be applied consistently and to allow the serrated nuts to bite the bus bar and not the small ring terminal of the sensing wire.
 

Short_Shot

Photon Sorcerer
I don't see the contact area as an issue. I believe the resistance in what is essentially zero distance to be minimal if you have good contact, use a conductive paste and use adequate torque. There are limits to what is an adequate surface area but I think any heat created by this joint will be quickly dissipated and in the end when it comes to conductors our primary concern is heat build up, is it not? I am a proponent of using a separate tapped connection to join the BMS sensing wire to the bus bar to allow the torque of the bus bar nuts to be applied consistently and to allow the serrated nuts to bite the bus bar and not the small ring terminal of the sensing wire.
You can believe it all you want but there are devices which can measure it.

If there's any heat at all (rather, any more heat than the cable itself) then it's a bad connection.
 

MrPhoton

Solar Enthusiast
Well, it took a very long time, but I finally received my 8 "new" 280 Ah EVE cells from Amy at Shenzhen Luyuan. All cells arrived well packed and in excellent mechanical shape, I will now start top balancing and putting together a battery for capacity testing. I am very happy with the company, Amy always gave me a good response in 24 hours or less to any of my questions. If I decide to order more I will start here, they are worth the premium.

Timeline for my shipment was as follows:

Payment cleared with Shenzhen Lyuyan: 7/9/21
Order sent out by Amy, she also sent me pictures of the shipment and a summary of the cell properties: 7/17/21
Received by FedEx in California and tracking number active: 10/11/21
Delivery to my door: 10/15/21

I'm sure the extra shipping time has to do with the current long backlog at the ports.

The only thing I'd like to see improved is a change to the studs welded onto the terminals; as many others have mentioned they really cut down on the contact area. Anyone have comments on how best to deal with this? I'm thinking of adding some aluminum washers with a tight tolerance clearance hole, this will at least get me full available contact to the stud while allowing slotted busbars that can tolerate a bit of misalignment, but of course this adds yet another metal to metal interface.
Sounds like our Batteries were cousins... having likely shared the same ship.
 

RayfromTX

Solar Addict
You can believe it all you want but there are devices which can measure it.

If there's any heat at all (rather, any more heat than the cable itself) then it's a bad connection.
With my YR1035+ milliohm tester I don't get a different reading on top of the bus bar than I do when testing straight onto the terminal. That is when testing through the cell. When I test between the terminal and the top of the bus bar, I get readings of .01 to .04 milliohms. That is pretty miniscule. I get .06 from one end of the bus bar to the other end when testing on top of the bus bar. I get .10 through the bus bar when testing at the aluminum terminals beneath the bus bar. I'm not concerned about .02 milliohms through this connection. I'm actually pleased with it. I try to test everything because a lot of the information available is mixed with opinion that gets passed around and takes on a mantle of authority.

What are the results that you get? I only tested 8 different connections but the results were consistent. I use carbon conductive past and torque the nuts to 5 NM.

I will test again when I install the new inverter this afternoon and start load testing my solar generator expansion. It may be different then. If it is I will update to this thread.
 

Short_Shot

Photon Sorcerer
So why would you double it by adding another terminal?

Or triple it with yet another.

Unrelated question:
I don't have that tester but can it measure straight dc resistance rather than just the AC impedance?

I really need to get one of them one of these days.
 

Dinky

Solar Enthusiast
With my YR1035+ milliohm tester I don't get a different reading on top of the bus bar than I do when testing straight onto the terminal. That is when testing through the cell. When I test between the terminal and the top of the bus bar, I get readings of .01 to .04 milliohms. That is pretty miniscule. I get .06 from one end of the bus bar to the other end when testing on top of the bus bar. I get .10 through the bus bar when testing at the aluminum terminals beneath the bus bar. I'm not concerned about .02 milliohms through this connection. I'm actually pleased with it. I try to test everything because a lot of the information available is mixed with opinion that gets passed around and takes on a mantle of authority.

What are the results that you get? I only tested 8 different connections but the results were consistent. I use carbon conductive past and torque the nuts to 5 NM.

I will test again when I install the new inverter this afternoon and start load testing my solar generator expansion. It may be different then. If it is I will update to this thread.
Ray,
I found your youtube channel and was so happy to have found it. Love the approach you use in your quest for relevance. Thank you so much! I'll be watching all of your content.
Kind Regards,
Steve
 
Top