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Some caps to ground on the balance leads would send the noise to ground. You just need to see what frequency you are dealing with and select the value base on that. I would still swap cell 12 with another just to rule out a weak cell.

I agree that introducing liquids in this manner is not a good solution. Especially when it requires a water rinse. Ensuring that the water completely removed would require baking out or time in a low humidity environment. Both would allow oxidation to return unless coated with a lubricant...

The BMS I ordered was a 120A. My needs are pretty simple for this project. It's a modern mini camper with all LED lights and a Dometic fridge that doesn't draw a lot of power. It's too small to consider running the air without shore power or generator. 200A and 300A BMSs are showing up...

You touched on one of the disadvantages which is the heat dissipation. The silicone will act as an insulator to retain heat. Depending on how much heat you are generating through current draw, this can become a big issue. It can also delaminate the bond between the metal and the silicone...

Well... It has begun! The panels, SolArk, and hardware were delivered this morning and the guys are on the roof installing the clamps now. They are saying it will be a 2-day install. Especially because we are expecting outer bands from tropical storm Eta to come through today. I'm...

I'm fortunate to work at a large corporation with lots of people who have side gigs, or know people who do. That's how I found affordable machinists. Ots rather like buying the cells from China. To get the good price, you have to accept the time table. The first guy already came in way too...

I figured you had already thought about that. I felt compelled to comment because I've been there without an oven trying to replace components on a ground or power plane. Many people have not, so it was a public service for those who don't understand the complexities of laying down parts on...

Thats the best solution. Good advance planning! There should be plenty of material to move up to M8. As @Ampster mentioned, I have heard that you need to be careful not to go any deeper. Supposedly, overtorquing the bolts can drive it through the bottom. The other concern is that you...

Here is the section of my plans concerning grounding of the panels. This goes through the Jbox to the AC ground in the SolArk.

Proper electrical design should always leave margin between the use case and the limits of the equipment. Probably not 50%, but a 20% derating is pretty common to ensure that problems do not evolve from pushing the limits. The temperature rise needs to be taken into consideration. A lot of...

I think your uncertainties are good enough to maintain the cells. Knowing that no one is going to ever send this out for calibration, I think you have set the bar high enough that over the lifetime, any drift will not put the system in danger.

I'm adding in high density foam 1-2mm thick between the cells to compensate for the expansion and contraction of the cells as they charge and discharge. The full range is only 0.5mm, per cell. This means very little relative motion from one cell to another as long as they are properly compressed.

I guess I'm just a glutton for punishment. I keep recommending it and taking my lumps. ? The connector lubricant is really important too.

@GMXnow, That is an interesting problem. I'm a little suspicious that #12 is always the low cell. Maybe swap it with another cell and see if the issue follows the cell? If you are using the prismatic cells with the blue wrappers, the outer case is tied to the positive terminal. Make sure...

The conversation has recently turned to the current capacity of bus bars by the area of the cross section. It sounds like you have expertise in the subject. I'm hoping you can provide information whether technical sources, or anecdotal from experience to put to rest the debate over how much...

Any Google search for information about crimps will turn up the Industrial Crimp Quality Manual. While there is only one mention of inserting multiple wires into a single terminal, if this is not a professional installation, subject to the electrical code, creating a larger wire from several...

I'm tracking. It's a pretty cool concept to jack up the AC voltage generating a voltage that is relative to the SOC. The theory seems sound. Detecting the frequency and synchronizing shouldn't be too hard. I just want some of what you're drinking! ?

I also took one of my bolts to the hardware store and confirmed the threads. The nice thing is, they even give you a torque spec. I'm not sure I believe that I can put 30inlbs on my 6063 bolt, but I'll see what happens at lower torque and work my way up.

As we spend trillions of dollars on cheap Chinese solar panels, we keep all of the Chinese factories operating. In the meantime, solar manufacturing elsewhere is going down the tube. When the tariffs level the playing field to compensate for the Chinese government subsidies, North America...

My 280Ah cells are rated to a 1C discharge rate 280A and they have 6mm bolts. Of course, it's not about the size of the bolt, but the cross section of the conductors in their entirety and the contact resistance. Clean your terminals and bus bars well in a low humidity environment, lubricate...

I was addressing the comment about the silver paste "sealing" the terminals. Please try to follow the conversation. Apparently you haven't read my links either. Galvanic corrosion has literally caused F16 fighter jets to fall out of the sky. Look it up. The M38999/ series of connectors...

You should not use a torque tool in the top or bottom 15% if it's range. They are known to be inaccurate at these extremes. There are many different types and sizes of torque tools. Do a search for tools that are in in/lbs and you will find a wide assortment.

Copper bus bar material came in today! If I go with this, there will be no questions about capacity should I decide to add another 4 cells. I'll probably need longer bolts!

I bought var stock to cut and drill my own.

Sounds like the sermon I've been preaching here the past month or two. I spent much of my career in avionics where corrosion is an ever present danger. Navy corrosion control school always stuck with me. I'm going with all aluminum until the lugs and wires. F-16 fighters crashed due to...

It looks like RS485 and CAN have the same connector unless I am missing a key or something. I don't need the box, but I would get a cable for $7. Thanks!

Cells charged back up with no issues. Full 280Ah. I haven't been able to take time to compile the data. It took about 4 days with the pathetic charge current. The balance was acceptable at less than 100mV between high and low. Leaving then on charge balanced them back to within a couple mV.

I was a Calibration Tech for years. Part of the job was to remove stickers from expensive instruments and apply another one to replace next year! I learned that anything with an oily base would neutralize the adhesive and allow it to be removed without damage. Goo-Gone, Goof Off, WD-40, coconut...

We have a mini camper. It's an Intech Flyer Pursue. Really, just a comfortable bed in an air conditioned, off-road ready box. They are really well made, so the investment in batteries to camp off grid for a while is worth it. I would rather keep the camper in the shade, so I plan to use...

I didn't believe it when I first read it. Sounds preposterous, right! I used a probe to poke through the blue wrappers on mine and they measured 0V to the positive terminal and 3.2V to the negative.