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Just finished with my upgrade. Went from 4 tired AGM 160ah batt to 1120 ah of EVE cells in a spring-compressed fixture. Battery: 16X EVE (amy) 280ah cells, separated by thin silcone sheets, fixtured with with hydro-cut aluminum end plates, threaded rod, and springs. BMS: REC Active BMS...

Just thought I'd share my implementation of a spring based fixture. I have separated each cell with a thin sheet of silicone. I like that material because it is heat resistant, provides some chafe protection, electrical insulation, and it "clings" to the cells with no adhesive, so it is easy to...

Thought someone might be interested... I installed a GX touch (cerbo) in my boat. I really like the system, but the viewing angle of the display is poor, and touching the screen was awkward with where I had it mounted. It looks washed out when looking from slightly above. I designed and 3d...

I've had a few people direct message me about getting this file. Here you go! Fusion 360 Project (so you can modify yourself): https://a360.co/3JjapBQ STL, STEP, and 3MF files in attached zip.

Hello everyone! I'm a full-time cruiser with my family of 4 on our Hanse 505 sailboat. Our boat is currently in dry dock in Puerto Penasco, Mexico for hurricane season while we visit friends and relatives for a couple of months. Our boat has a tired 12v 640ah AGM battery bank and 750w of solar...

You can do all those things projects with a 3d printer. There are all kinds of filaments with different properties available. I live on my boat, so I have a Prusa Mini which is very compact, yet still has a decent 180x180x180mm print area. I use it all the time for mechanical and outdoor parts...

Thought you might be interested to see how my actual build turned out compared to my 3-D model posted up thread.

I forgot to update my own thread on my progress! I ended up making wire interconnects. I used AWG 4 (ampacity 160a) for the parallel connections, and AWG 1/0 x 2 for the serial connections. Each 1/0 cable has an ampacity of 285a, so total of 570a for serial connections. I'm happy that they have...

I'm sure everyone is tired of talking about cell compression. I know I'm tired of reading about it (I've read many posts on many threads about it). What I'm hoping to discuss in this thread is compression and bus bars, but only as it relates to the integrity of the terminals. I have 16 EVE...

I have the “Main normally closed” (REC terminology) BMS relay output hooked up to the open(disconnect) signal wire on the ML-RBS. The normally closed relay is open when the BMS is happy. When the BMS detects a fault, or is turned off, it closes the normally closed relay, which opens the...

I got the (I guess wrong) impression that 400a was max from reading the Blue Sea fuse selection chart and seeing that the maximum class T size was 400 amp. Also, The marine stores I frequent seem to only carry up to 400 amp. Here is a link to the chart...

I wish. This is retrofitting a boat, which already has two electric 12v winches, and electric 12v windless, and a couple of other high amperage 12v loads that would be cost prohibitive to replace.

I don't think I'm going to go in that direction. I really like how my system degrades gracefully if the network goes down, but if the network is up I have centralized logic. The problem is that I gave it a poor parameter for when I'm away. I think I'm on the right track to giving it a better...

Great point, and yes, I have mostly Victron equipment, which is one of the reasons I went with an REC Active BMS, which speaks "Victron". One of the reasons I decided to go with a 4P4S setup, rather than 4S4P is I want just one BMS "to be in charge" and communicate the charge needs of the bank...

Below is my current 12v-->12v plan... Background I have a Hanse 505 “Sauvage” built in 2015 that I have owned for 2 years now. Our family of 4 have been full time live-aboard for 1.5 years, and have covered about 6000nm in that time, starting in Hawaii, then Seattle, now Mexico. Despite being a...

The two previous replies seem to conflict a bit. Maybe can be explained if @newbostonconst is discussing the parallel links only, and @Scph9002 is discussing serial links. I've had a bit of a think about it, and made a diagram with my guess about what is going on. I've labeled the current...

This post is absolute gold, thank you. Those clicks as tension releases confirms my growing suspicion of solid bus bars and your slop at low SOC throws into doubt how good an idea a simple (no spring) clamping fixture is for mobile/offroad situations. I like your new pack solution, and I think...

I appreciate the suggestions, even if I don't do them, because it makes me think through why I'm doing what I'm doing more carefully, and it often leads to changes in my design. I thought about 4P4S vs 4S4P pretty carefully, and there are a bunch of reasons 4P4S will work better for me, using a...

I read lots of this thread, but not all, so forgive me if I'm retreading old ground. I just bought springs (9-1010-26 5/8 X 2-1/2 RED DANLY DIE SPRING) from suprdie.com for cheap! According to their data sheet (https://www.daytonlamina.com/pdf/DS117_DieMax_XL_Springs.pdf) these have a length...

I’m open to other configurations of 4P4S, but I’m not doing 4S4P. Both have pros and cons, and I’ve read a lot about it, and I’m comfortable that I prefer to parallel cells before I put them in series to form one large battery.

These look nice, but how flexible can they really be?

What do people think of using the Class T fuse inline without a fuse block, like she did?

I appreciate your input, but I don't agree. You say I'm "getting away with my design" and that Q-Dog mentioned my design was wrong. Yet I cited sections of both the Victron Cerbo manual and the REC BMS manual that indicate my architecture is just fine. Nobody has mentioned a concrete reason, nor...

You might be right about this. I'm an optimizer, and the idea of the batteries being at 100% by 10am worries me a bit, but maybe I'm being too much of a perfectionist. Or maybe I just need to find the "right" charge voltage! That will be an experimental process though.

Very nice looking. What is the ampacity, and do you have a resource to share describing the construction? I'm on a boat, and have a small vice, but no press, and I worry that without a gas-tight connection, that resistance would get worse over time. The appeal of the wire+lug approach, though...

Do you have personal experience with compression effectively stopping strain, or a good source to cite? It seems to me that even compressed lightly at 50% SOC, that a battery bank ranging over 10-100% SOC could result in some movement as the cells expand and contract.

I'm planning on assembling a 4P4S battery bank. Hypothetically, if I used the layout in the attached diagram, and was pulling, say, 100 amps, how many amps would be flowing through each link? My instinct is that the serial links would have more amps flowing through them than the parallel links...

That first picture (Clamp) is the kind of thing I'd probably make a lot of.. And then it would live its life in the sun.. ASA is very UV resistant, and will hold up fine outside.

That’s the missing piece for me. I didn’t catch that you are going 4S2P, rather than 2P4S. If you don’t want to parallel cells, you do need multiple BMSs, and I guess I wouldn’t recommend a centralized REC style BMS to you. I fall into the opposite camp. I think the pros of a 4P4S outweigh the...

Excellent point about a weakness of the wire interconnect approach. I will try to mitigate it by using top quality wire, and dipping the ends as you described. Lucky for me I have a pretty modern boat, with a dry bilge, and my battery box area tends to say quite clean and dry. I’ll also run my...