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This was discussed earlier in the thread about the separate wires coming off the BMS. This is how I dealt with them.

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...

I have a background as a Test Engineer and I am building my first battery from cells. I have some pretty good equipment and I wanted to share with the group what kind of information I manage to acquire as I apply my trade to this new endeavor With an eye towards the science of this emerging...

I just did a quick experiment. I started off with my Fluke 87 from the negative terminal to the case. It measures 3.2V I added a 5.1kohm resistor in parallel as a load and it dropped to 2.4V. The resistor didn't heat up. As an extra step, I replaced the resistor with a 10ohm power resistor...

I went around this block with my installer and ultimately an Engineer at SolArk. The communication between inverter and BMS is not required. It's a nice to have, but the SolArk will spend the first couple days of its life exercising the batteries to determine the capacity. I'm pretty sure...

The inspection was last Tuesday morning. I walked around with him and then left for a 4 day hunt on an island. Just now catching back up. Since the code didn't require the RSD, I took advantage of not having them installed. I need to get them back out to connect the loads and turn it on...

I wasn't familiar with Noalox and just read up on it. This is not a panacea that protects copper to aluminum junctions. First of all, it introduces two additional metals, zinc and silicon. As the grease dries up, it will exacerbate the galvanic reaction over time. Granted the zinc will...

After much research and consideration, I have moved away from the Enphase solution. Most of it stems from the expense of the Encharge batteries. It was a very difficult decision because of all the positive things about their products. In the end, the science won out. The continual conversion...

Here we go, Done for the day. All but one panel is in place. The last one will cover the roof penetration and the wires leading to it. Tomorrow is bringing the PV power in and installing the SolArk in my cabinet, here: Then tie it to the grid.

I asked for the EMP version of the SolArk and paid the extra. It took a couple weeks to arrive. There is no way they could have got a special order from China that quickly. There has to be some value being added in Texas. My perspective is that, these are just like your wireless phone or...

The first couple orders, you get a little stressed due to the length of time between order and delivery. After you experience the process, you realize that the vendor doesn't get paid until you acknowledge that you received the product intact. They want you to get your product as much as you...

Good and bad news today. Only 12 of the 16 cells in the 2nd order were delivered today. Hopefully, the 4th box will show up tomorrow. I unboxed the first shipment, and even though the boxes were a little worse for wear, the cells are beautiful! I did a quick voltage check and every cell is at...

System #1 1. JBD Smart BMS w/Bluetooth dongle 2. 4S (12V) Common 3. 120A 4. $72.43 US delivered 5. Satisfied 6. https://a.aliexpress.com/_mqE7ZWr System #2 1. Heltec 2. 16S Common 3. 200A 2A Active balance 4. $207.58 US delivered 5. TBD, waiting on cells to be delivered. 6...

You're right. I'm still waiting for the tracking number to go active on the FedEx site. Pylontech is one of the companies whose BMS is known to be compatible with the SolArk that I will be providing the energy to. If I wanted to pay their price for batteries for my solar backup, I would have...

Having spent many years in the Navy Avionics world, then living in Florida, corrosion is an ever present destroyer. Galvanic corrosion in particular needs to be addressed in the design phase it needs only moisture in the air like humidity to come about. If you think that "sealing" your...

I've been dabbling a bit at making aluminum bus bars for a while. I've decided to get serious about it and get some made that should never need to be removed no matter how much current I want to pull. I'm making them from aluminum, so galvanic corrosion will not be an issue. 3/8" thick...

I spent some time looking for this answer and came up with the calculators that get me what I was looking for. Start at Engineer's Edge clamping force calculator. https://www.engineersedge.com/calculators/torque_calc.htm Notice that the torque is in N/mm instead of Nm, so 8Nm would be entered as...

I ordered the cells from Shenzen UNIS. The pandemic made the delivery time 52 days. They arrived in good condition. The only physical damage was one label on top of a cell was peeled up on one end. It might have happened when sliding the cell into the box and the edge caught the foam. They...

My tracking number went live yesterday!? Delivery is supposed to be on Tuesday. I'll post more when they arrive.

I spent way too much time reading through this whole thread. Great stuff to cut my teeth and make my first order through Alibaba. Thank you all for the education! Now, after saying that, I'm not going to follow one of the prime recommendations found here. I found that Shenzhen UNIS has a...

Having spent quite a few years in manufacturing, I have seen that most products are not labeled with an exact date. Usually there is a lot code. Most of you probably know that a "lot" is one batch of material. Tracking the lot is more valuable because if something went wrong with that batch...

Absolutely! In general, a connector lubricant is purpose made to prevent corrosion and preserve conductivity of the connection. One in particular, MIL-L-87177 put into service by our military to prevent F16 fighter jets from falling out of the sky due to galvanic corrosion...

There is significant evidence that even "sealed" military grade connectors will have oxygen and moisture intrusion. This has brought down several F-16 fighter jets. Like @Luthj said, moisture is a key ingredient in corrosion and salt accelerates it. For my application, I am using all...

With the aluminum posts on the batteries, there is the opportunity for galvanic corrosion between the post and the copper bus bars. This can cause more resistance in the connections.

Please see the bottom of page 4 of the attachment. This is the datasheet for the EVE 280Ah cells. Definitely M6

I'm building the same 48V system with 280Ah cells. I thought I would offer a little of my insight to this thread. I don't see that anyone considered the corrosion aspect of the bus bars. Copper connected to the aluminum terminals, especially in an environment where humidity or other moisture...

Terminals on the 280Ah cells are 16.2mm or 0.638" in diameter

Batteries arrived today! Ordered April 20, shipped April 28. 52 days in transit. In good condition. One cell had the label stick to some foam and peeled up. Terminals are clean and unused. Looks like they have been used once to test. 2 extra brass bolts and 1 extra copper bus bar. Bus...

Alright, I took the BMS off the system to work on the wires. It really bothers me to have 3 separate wires to carry the current into and out of the BMS. Thus far, I was using just one wire and was able to pull 40A constantly and the wire was just warm. I got into a little debate with someone...

Yes, stainless is soft. I used to spend some time in a machine shop with a self proclaimed "A$$hole" who lamented every time he had to mill something made of stainless. Those are the tradeoffs of strength vs corrosion resistance. Electrical conductivity does not require an enormous amount of...