Interesting. It looks like it requires a wired (serial?) connection. My bms’s didn’t come with any connection wires, I guess I need something. Need to research. One thing that bothers me a little about the overkill bms’s is that there is no way to lock down access via Bluetooth (except disabling it all together). Someone could shut off all you batteries, reset parameters, etc. probably a really low risk, but hard wiring it to the cerbo would address that and also allow remote access.PS. Are you aware you can hook-up the BMSs you've used to the Cerbo to get the data in the Victron VRM?
GitHub - Louisvdw/dbus-serialbattery: Battery Monitor driver for serial battery in VenusOS GX systems
Battery Monitor driver for serial battery in VenusOS GX systems - GitHub - Louisvdw/dbus-serialbattery: Battery Monitor driver for serial battery in VenusOS GX systemsgithub.com
13 kWh Lishen van build
- Thread starter blutow
- Start date
pau1phi11ips
Solar Enthusiast
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- Dec 17, 2019
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It looks like Bluetooth support will be added to the driver at some point so maybe that would help with the security?
github.com
If it's paired and connected to the Cerbo/RPi then I don't think it'll accept other connections. Not 100% about that tho.
Add bluetooth support · Issue #13 · Louisvdw/dbus-serialbattery
It would be good to have the driver use bluetooth to connect from the VenusOS device to the BMS The latest rPi images has bluetooth enabled. A GX device will need a USB bluetooth dongle. It will ne...
github.com
I don't think the cerbo would prevent another connection, but not sure about that either. I think the only way to prevent open , bluetooth access on those BMS's is to disconnect the bluetooth. If I had a serial connection to the cerbo and could see all my BMS info, that would give me a path to the data without the big security hole.It looks like Bluetooth support will be added to the driver at some point so maybe that would help with the security?
If it's paired and connected to the Cerbo/RPi then I don't think it'll accept other connections. Not 100% about that tho.Add bluetooth support · Issue #13 · Louisvdw/dbus-serialbattery
It would be good to have the driver use bluetooth to connect from the VenusOS device to the BMS The latest rPi images has bluetooth enabled. A GX device will need a USB bluetooth dongle. It will ne...
I finally completed individual cell testing today. 1 cell every 2 days, right on target after 32 days with no issues or surprises.
Final results below. Capacity ranged from 282.29 to 288.84 AH. They were all tested using the same protocol. I detailed that in a prior post. Bascially, I ran each cell up to 3.62v and ran the test until the cells hit 2.61v (which was the cell voltage when the tester shut down on low voltage at 2.5v).
The 2 "low" cells (282 and 283) were my only 2 cells with silver vents. All the others had the blue vents. Obviously from a different batch. They were the cells triggering low/high disconnect in my pack testing when running them all the way up and down. If those are my biggest problem cells, I'm happy.
I really don't know that testing all these cells is going to make any measurable difference, but I am grouping them by capacity. As final prep for service, I'll charge them back up in series, do a final top balance, and then cycle each group a couple times for a final check.
Final test results from my last cell today. This cheap battery tester has been working pretty much non-stop for the last 32 days. I'm thankful it didn't burn my house down. I installed a basic smoke alarm over my workbench before starting any of this stuff.
I also installed my rooftop AC unit on the van last weekend. I'm not planning to run the AC off my batteries for any extended time, but it will be nice to have the option in 1-off situations.
Final results below. Capacity ranged from 282.29 to 288.84 AH. They were all tested using the same protocol. I detailed that in a prior post. Bascially, I ran each cell up to 3.62v and ran the test until the cells hit 2.61v (which was the cell voltage when the tester shut down on low voltage at 2.5v).
The 2 "low" cells (282 and 283) were my only 2 cells with silver vents. All the others had the blue vents. Obviously from a different batch. They were the cells triggering low/high disconnect in my pack testing when running them all the way up and down. If those are my biggest problem cells, I'm happy.
I really don't know that testing all these cells is going to make any measurable difference, but I am grouping them by capacity. As final prep for service, I'll charge them back up in series, do a final top balance, and then cycle each group a couple times for a final check.
Final test results from my last cell today. This cheap battery tester has been working pretty much non-stop for the last 32 days. I'm thankful it didn't burn my house down. I installed a basic smoke alarm over my workbench before starting any of this stuff.
I also installed my rooftop AC unit on the van last weekend. I'm not planning to run the AC off my batteries for any extended time, but it will be nice to have the option in 1-off situations.
Not a dumb question, you need something l
Not a dumb question, you need a special meter to do it. See pic below. My understanding is that these are not terribly accurate on cells larger than 100AH, but it's what most of the vendors use when testing/matching by IR and voltage. I was mostly concerned about comparison between cells, not absolute value, so I think it worked for that. I paid ~$45 on aliexpress for it.
Much like the cheap capacity tester I bought, I don't think this is required equipment if everything is working well. I bought it for sanity checking my cells and and so that I'd have the ability to trouble shoot (and dispute with vendor if needed) in case I had problem cells. All of my Basen cells were labeled with .12 IR, but they varied on arrival between .12 and .16 per my tester. I'm guessing Basen really didn't check them, but who knows. The cells seem seem to be match well enough to function properly and the capacity is good, so no complaints here for what I paid.
I got my solar panel installed yesterday. I've been top balancing and cycle testing all my packs now that they are sorted by capacity. I have completed the testing on 3 of the 4 and the results are good. No drastic changes after being matched, but a little less issues with runners at the top and bottom. One more pack to test tomorrow and these things will be ready for final assembly and install. I have 2 more side windows to install in the van this coming weekend and then electrical install is next step. It's likely to take me several weeks since I still have work to do on the battery boxes and I'll need to fabricate a cabinet frame for mounting everything.
tim0shel
Solar Addict
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- Jan 27, 2020
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Wow so impressive. I so want to be doing a van build but yet have purchased a van. I guess some cars need to go in order to do so but hard to part with some.
Really love what you did with the battery boxes. Looking forward to more updates and follow the build. Maybe to get some ideas as well. Maybe I missed it but what solar panel is that you have?
Really love what you did with the battery boxes. Looking forward to more updates and follow the build. Maybe to get some ideas as well. Maybe I missed it but what solar panel is that you have?
Thanks. It’s a solaria 400 watt panel
Looks like an amazing build, i am pretty much going with the same thing even though solaria panels are really hard to get here in AUS. No retail availibility. Same victron stuff, just 48v and then downstep. for 12v for usb and like lights to save some cash on copper and other components.
Just the aircon in the bus might have to be 230v so i lose that saving on a bigger inverter. But that would be worth it in my opinion.
all in all with the van you have i would of build the same! looks great.
Just the aircon in the bus might have to be 230v so i lose that saving on a bigger inverter. But that would be worth it in my opinion.
all in all with the van you have i would of build the same! looks great.
I've been working on the rear wall for all my electrical equipment. It's been slow going, lots of thinking and small steps. With the weight of the inverter and batteries, I really wanted make sure it was solid, so I used a mix of 1/2 hex board with 1/8 steel support. I used a bunch of rivnuts and also used some additional 1/8 flat to attach everything and make for a flat wall. It's a challenge on a sprinter when you go beyond the bottom section because it starts curving in as you go up. I had to router out recesses in places to allow for the curve and also some sections of track for my bed support.
I've got the wall pretty much complete and now I'm laying everything out in my garage and then it should be ready to install. I'm thinking another ~3 weeks and I'll have the electrical up and running.
I've got the wall pretty much complete and now I'm laying everything out in my garage and then it should be ready to install. I'm thinking another ~3 weeks and I'll have the electrical up and running.
pau1phi11ips
Solar Enthusiast
- Joined
- Dec 17, 2019
- Messages
- 40
Nice, looks neat! Are you gonna insulate the wheel arch tho? Doesn't look like there's much room left. Even if the climate doesn't need insulation adding something to the arch will help with road noise while driving.
I'm using 8 280Ah cells so I figured having them on the floor would be best given the 40kg weight. Also don't have a welder so don't really have a choice
I've got almost the same Victron kit but gone with the 24/3000 Multiplus II. Lighting, Heater and Fridge all work off 24V and could save money on cabling and on the MPPT.
I'm using 8 280Ah cells so I figured having them on the floor would be best given the 40kg weight. Also don't have a welder so don't really have a choice
I've got almost the same Victron kit but gone with the 24/3000 Multiplus II. Lighting, Heater and Fridge all work off 24V and could save money on cabling and on the MPPT.
Yes, definitely. I'll be adding a layer of hush mat and still debating how to further insulate. There are some thick OEM foam/rubber-ish panels that fit over the wheel wells I might go with. Not the best insulation, but probably good enough. I could stuff some thinsulate in the space once I have my cabinet in place, we'll see.
Back to the batteries...
I finally finished the other 3 battery boxes and installed all the cells. I decided to switch from hdpe to this hex board plywood material I've been using for the van. It's plywood with a hard shell coating on both sides.
Next step is to get the BMS's installed and then I still have some work to do on my other electrical system wiring.
I finally finished the other 3 battery boxes and installed all the cells. I decided to switch from hdpe to this hex board plywood material I've been using for the van. It's plywood with a hard shell coating on both sides.
Next step is to get the BMS's installed and then I still have some work to do on my other electrical system wiring.
I am trying to optimize space and also thinking about weight distribution. The 4 batteries are about 250 lbs total and having them directly over the rear axle vs. sitting in the back corner was preferred, particularly considering where other heavy things in the van will be located. It does move the weight about 12" higher compared to floor mounting, so center of gravity is pushed up a little as a trade off. I couldn't have fit all 4 on the floor and even 2 stacks of 2 on the floor behind the wheel well would have been really tight. Mounting them sideways wasn't a good option because it would have made my electrical cabinet much deeper and cut into my garage space. These things are pretty big, so it's not the same as sticking in 4 100Ah battleborns.
The material is more like plastic/resin coated plywood, not rubber. It has a black phenolic coating on both sides sandwiching the plywood. Very durable and easy to work with. The finish looks nice and saves the time and mess with painting/finishing. Any place you make a cut exposes the plywood, so some black paint can be used on edges where it could be exposed.
Penn Elcom - Film Faced Panels
www.penn-elcom.com
I think in terms of space optimization this is great, but are you not concerned with free-floating that much weight? Or are you going to have something that extends to the floor as well?I am trying to optimize space and also thinking about weight distribution. The 4 batteries are about 250 lbs total and having them directly over the rear axle vs. sitting in the back corner was preferred, particularly considering where other heavy things in the van will be located. It does move the weight about 12" higher compared to floor mounting, so center of gravity is pushed up a little as a trade off.
Penn Elcom - Film Faced Panels
