Search results

Something else worth noting (that Dacian mentioned to me) is that, although the serial port is technically 2 wires, because the SBMS can't/doesn't receive any data you can get away with one wire. There was also the necessity to opto-isolate or magneto-isolate the serial line between the two...

A portable battery power kit (charge controller, batteries, inverter, connectors, etc all in a compact box). It began with wanting an external display showing specific data I cared about but then morphed into all sorts of other enhancements as I came up with ways I could control/respond to...

I have done this for a project I was working on, although I haven't touched the project since 2021. I was surprised at the time that no one else had done this before as I too was frustrated by the complexity and was hoping like you to build off from someone else's code. But even emailing Dacian...

They have 3 serial interfaces. You can check all the specs at: https://www.pjrc.com/

Check out the Teensy microcontrollers. Ardunio-compatible but with more storage and data pins. The Teensy LC has 27 data pins and 64KB storage. The 3.2 has 34 pins and 256KB. I've been using them and been happy.

Logic level converters. I've used them, they work great.

Pretty easy to make. I made my own. You can buy the braid on eBay. I got nickel-plated braid and plated copper tubing since the battery terminals are aluminum (grr) and copper+aluminum=bad

One nice thing about flattened copper tubing is that you can flatten it over lengths of copper braid, since there are risks with using solid bus bars damaging the terminals as batteries expand/shrink.

Phantom power drain even with no load on the inverter.

It's for small units (portable) where size/space is a constraint. Not every use case has the luxury of unlimited space/weight for more batteries and more panels. When some variables are limited, it's reasonable to want to save the 10-20% lost efficiency of an inverter if a straight-DC solution...

The video Bud posted 2 pages back from Bigbattery.com re: their Lishen batteries suggests otherwise (they're wrapping them specifically to insulate them electrically)

I'm going to test my EVE cells next time I pull them out from my work-in-progress project. I'm rather shocked that the outer case is tied to one of the terminals, considering how frighteningly thin the blue wrap is. I know for a fact that simple handling of them nicked the blue wrap in a few...

My current plans for my portable kit includes something along these lines. Although it won't be particularly well-calibrated... mostly to satisfy my curiosity in how cell pressure changes relatively over the course of the charge cycle. I'm still working out the details and it depends on whether...

Cost and weight. Aluminum is 1/3rd to 1/4th the cost of copper, and 30% of the weight. But mostly cost. Those Yuans add up.

2ch isn't totally necessary, since the solar panels aren't permanently connected. They're only plugged in while it's being used, then unplugged when it goes into storage. Knowing to always make sure the panels are unplugged before throwing the battery disconnect to OFF would not be a problem...

So I've been quiet for a while because I've been busy on my project, which is moving slowly only due to life, otherwise it's moving well. But as I was studying my wiring diagram, I got to thinking once again about the idea of a master battery disconnect, which ideally I'd want but was told...

Can't be that hard to find, I just looked and I happen to have 2 in my possession already. One is fixed at 2 in/lbs, the other goes from 0.3-1.15 Nm which is 3.1-10.18 in/lbs. My other one goes from 15-75 in/lbs.

Doesn't seem like Dacian thinks highly of the clone (which he authorized, but didn't have input into). https://groups.google.com/forum/embed/?place=forum/electrodacus#!topic/electrodacus/TG3lMy3IPv4

There appear to be lots of options for corrugated alluminum panels, most from mfrs in China and India. Metawell would be an alternate company (German)

This is inspiring me to incorporate a battery pressure sensor into the kit I'm building.

Total shot in the dark: Gravity pulls more of the electrolyte to the bottom of the cell, so the bottom experiences slightly more expansion/contraction as the cell is cycled.

Question: on the SBMS40, what area of the back gets the hottest? My heatsink isn't quite big enough to cover the whole thing so I wanted to place it over the power MOSFETs or whatever. I remember once seeing a cut-away showing the internal design layer by layer but I can't find that again after...

So 8 years ago I started dabbling in solar, and envisioned a portable self-contained kit that I could take with me camping, to festivals, etc. It would provide me power to charge my phone, inflate my air mattress, run lights at night, and anything else. I figured I could cram a battery, charge...

I have found Dacian to be extremely generous and responsive in filling in the blanks whenever I needed help above and beyond what the manual provided (or just interpreting what was in the manual). I wouldn't have been able to get as far as I have without all his email help.

I learned everything I needed from the manual. Although ultimately I'm taking it even further and using the serial data stream to an Arduino to give me even more functionality.

I'm planning on incorporating heating system in my kit to address this. While I don't ever expect to have the kit exposed to conditions that would require it, I like the failsafe of having it there just in case. I have a number of thin-film 12V heating elements that will go in-between the cells...

Does the SBMS40 also not do the "active" balancing in the sense of your definition? I'm not sure I fully understand the degree that my SBMS does "balancing".... I'd like to understand my product better.

These are heavy batteries. You put 4 in a box and you're already at almost 50 lbs. There are issues with really heavy boxes and shipping... higher rate of damage, "overweight" shipping premiums, OSHA/union rules about what their workers are expected to handle, etc. My four batteries came in two...

This seems counter-intuitive to me as well. From what I can tell, the expensive cells (Winston/Thundersky, CALB, etc) build their cells with a hard plastic case to provide a degree of structural integrity and make compression easier. The cheaper cells (EVE, etc) skip this, resulting in smaller...

The SBMS will be inside of an enclosure. I'd like a secondary display to show some key data that's visible even when the enclosure is closed. I'll also have an RGB LED that indicates various statuses that's visible from a distance (and in the dark). I can also incorporate other data from other...

Thanks for your detailed response. Since posting that, my project has progressed and evolved a bit. Most importantly, I've moved from trying to control/display things directly from the SBMS to creating a data link between the SBMS and an Arduino. That gives me far more flexibility (and pins to...

If they aren't EVE cells, then they are knock-offs designed specifically to look exactly like EVE cells. The dimensions, weight and unique telltale design features match EVE 280Ah cells exactly.

I think the problem here is when someone needs detailed technical info... there isn't an authorized/licensed, certified, trained, etc "EVE Dealership" with all the inside scoop. A more-accurate analogy would be if you have a technical question about your Onkyo AVR, but when you call Onkyo they...

The included bus bars are pretty poor quality, quite honestly. You're better off buying some better ones. Even cheap ones you could make yourself would be better.