48 grade A 280Ah LiFePO4 cells from Dongguan Billion Electronic Technology

LiFer

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Mar 16, 2020
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Boston
Hello folks,

I recently received 48 brand new grade A 280Ah LiFePO4 cells from Dongguan Billion Electronic Technology Co., Ltd. via Alibaba.
The person I communicated with was Yau Tim.
Everything arrived very well packaged. Some outer boxes were slightly scrunched from shipping, but the inner boxes and foam padding seemed in perfect shape. The batteries looked perfectly brand new and are not damaged (I wouldn't expect them to be given how well they were packed).

The batteries arrived on schedule and I tested the voltages today (July 13, 2020) to be 3.296V - 3.298V.
I received a video showing the pre-shipping voltage of the batteries were 03.28V - suggesting they should have used the next notch over on their multi-meter, but I'm not concerned.

Tim included a free bag of _copper_ screws! I didn't ask for them, and I thought it was a nice touch. No galvanic corrosion between my copper screws and copper bus bars. It also looks nice and saves me from making a mess with NOALOX - at least for that connection.

Total cost was USD $4,635.89 DDP (by sea). FedEx dropped the batteries off at my front door.

I'm meeting with my electrician tomorrow to make a plan, so I probably won't have them powering my house for a couple of months (permits, national grid, etc.).
I'll try to answer any questions - just keep in mind that I have trouble finding the time to visit this site every day.

I didn't include a pic because they are standard EVE batteries (M6 screw). They seem to look identical to the other 280Ah batteries posted to this forum.
 

Bleedingblue

Solar Enthusiast
Joined
May 12, 2020
Messages
398
Hello folks,

I recently received 48 brand new grade A 280Ah LiFePO4 cells from Dongguan Billion Electronic Technology Co., Ltd. via Alibaba.
The person I communicated with was Yau Tim.
Everything arrived very well packaged. Some outer boxes were slightly scrunched from shipping, but the inner boxes and foam padding seemed in perfect shape. The batteries looked perfectly brand new and are not damaged (I wouldn't expect them to be given how well they were packed).

The batteries arrived on schedule and I tested the voltages today (July 13, 2020) to be 3.296V - 3.298V.
I received a video showing the pre-shipping voltage of the batteries were 03.28V - suggesting they should have used the next notch over on their multi-meter, but I'm not concerned.

Tim included a free bag of _copper_ screws! I didn't ask for them, and I thought it was a nice touch. No galvanic corrosion between my copper screws and copper bus bars. It also looks nice and saves me from making a mess with NOALOX - at least for that connection.

Total cost was USD $4,635.89 DDP (by sea). FedEx dropped the batteries off at my front door.

I'm meeting with my electrician tomorrow to make a plan, so I probably won't have them powering my house for a couple of months (permits, national grid, etc.).
I'll try to answer any questions - just keep in mind that I have trouble finding the time to visit this site every day.

I didn't include a pic because they are standard EVE batteries (M6 screw). They seem to look identical to the other 280Ah batteries posted to this forum.


I have the exact same order with the same company. When did you place your oder (wait time)?
 

LiFer

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Joined
Mar 16, 2020
Messages
60
Location
Boston
Paid May 10. Received batteries on ~July 3 - July 6 (I wasn't home / on vacation).
Edit: I did receive one box a week earlier. It looks like it was sent on a different ship. It was nice to get 1 box early so I could verify measurements etc.
 

Bleedingblue

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Joined
May 12, 2020
Messages
398
Paid May 10. Received batteries on ~July 3 - July 6 (I wasn't home / on vacation).
Edit: I did receive one box a week earlier. It looks like it was sent on a different ship. It was nice to get 1 box early so I could verify measurements etc.


I looked mine up and i wired them the money on 6-9-20.

Mine may be in customs
 

LiFer

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Joined
Mar 16, 2020
Messages
60
Location
Boston
Hmm. After taking the screws out of the bag and inspecting them more closely I see that they are not pure copper screws - they look like brass. I've asked Tim if they are brass/zinc or brass/tin (or ...?). Maybe some of you can tell from a picture? They aren't the bright brass color that I normally associate with brass. The left-most screw was polished a bit on my bench grinder - so that's about as bright as these get.

Tim (battery seller) may not know, but if he does I'll post his response.
The (smaller 384A) 1/8" x 1 1/2" copper bus bar on the left is Copper C110 for a color reference.

brass_screws.jpg
 

Luthj

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Jul 1, 2020
Messages
951
1595293124959.png

Brass is copper and zinc, bronze can have various alloying elements, but typically at least 10% tin.
 

LiFer

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Joined
Mar 16, 2020
Messages
60
Location
Boston
Thanks for posting the pic.
The screws do look like brass.

I found an article explaining that the zinc can leach out and one way to prevent that is to create a brass alloy by adding Tin:
( https://www.metalsupermarkets.com/difference-between-copper-brass-bronze/ )

Tin Brass
This is an alloy that contains copper, zinc and tin. This alloy group would include admiralty brass, naval brass and free machining brass. The tin has been added to inhibit dezincification (the leaching of zinc from brass alloys) in many environments. This group has low sensitivity to dezincification, moderate strength, high atmospheric and aqueous corrosion resistance and excellent electrical conductivity. They possess good hot forgeability and good cold formability. These alloys are typically used to make fasteners, marine hardware, screw machine parts, pump shafts and corrosion-resistant mechanical products.

Elsewhere I note: https://www.zygology.com/cms/upload_area/pdf/Zyg-Anodic-Index.pdf

Where brass has an anodic index of 0.40 V - which is very close to copper.
Perhaps as long as the zinc doesn't leach out? As zinc is at the far end (bad) of the index at 1.25V.
 

Luthj

Photon Sorcerer
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Jul 1, 2020
Messages
951
zinc leeching is an issue in marine environment. Not in a dry battery box.
 

Bleedingblue

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Joined
May 12, 2020
Messages
398
Hmm. After taking the screws out of the bag and inspecting them more closely I see that they are not pure copper screws - they look like brass. I've asked Tim if they are brass/zinc or brass/tin (or ...?). Maybe some of you can tell from a picture? They aren't the bright brass color that I normally associate with brass. The left-most screw was polished a bit on my bench grinder - so that's about as bright as these get.

Tim (battery seller) may not know, but if he does I'll post his response.
The (smaller 384A) 1/8" x 1 1/2" copper bus bar on the left is Copper C110 for a color reference.

View attachment 18000


In my stereo that has over 6000 watts i used brass/zinc fasteners for good current transfer. Works just fine.

Dont know what theirs is but looks similiar
 
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