13 kWh Lishen van build

[pau1phi11ips]

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 think having some struts that connect battery boxes to the floor to hold some of the weight would be a good call. Going over pot holes and bumps in the road would be a big shock load.

 

[blutow]

The battery boxes have tabs on the front that will bolt to the steel frame of the electrical cabinet (which will run to the floor). I'm honestly not sure support from the front is needed, but I figure more support is better and I was using steel angle for the cabinet frame anyway.

The mounting approach to the side wall for each battery isn't just 4 bolts in plywood or into the wall. Those bolts are welded to flat bar steel and then those steel supports are attached to the wall at many points to spread the load. The 2 bottom batteries also rest on the wheel well and the 2 top batteries rest on the bottom batteries. All that support is only on the wall side however. The concern is not really downward force, but there is a possibility of downward force translating to twisting force since only the wall side is supported until it's tied into the cabinet frame.

 

[blutow]

Getting close. Batteries are fully assembled. I'm in the process of charging up each pack before I do some charge/discharge testing of the 4 running together. I figured it was worth running a couple more tests before installing to make sure I don't have any hot spots or bad connections.

 

[pau1phi11ips]

Looking sick dude!

 

[blutow]

It's alive. All the core stuff is installed and running. I still haven't run the cable to the chassis battery/alternator, so the Orion B2B chargers are not connected yet.

I ended up top balancing all the packs again. The cells had been sitting loose for about 7 weeks and I had one cell running a bit when I reassembled and charged the packs up.

I've been running my AC for about 5 hours today as a test (compressor on continuously since the van isn't insulated yet). With other stuff running as well, it's been a constant pull of 1200-1400 watts from the batteries. With partial cloud cover, solar has been ranging 100-380 watts (single 400w panel). My shunt is a little warm, but everything else is staying cool and the cell voltages are nice and tight (as expected in the middle of the curve).

It's taken a long time to get to this point, but there is still a lot to do. I am running my 120v off an extension cord right now and I only have a fan connected on the DC side. I need to mount my control screen and also clean up some of the wiring.

I plan to run all 4 packs up and down a couple times to see how they work together.

 

[Chris30559]

Looks amazing, great job. I do have one question, as great as the battery boxes turned out, why so much concern about keeping them compressed? I was under the impression that only specific chemistries had to be compressed and LiFePo4 was not one of them? Please correct me or point me to a thread that explains the reasoning behind this if you don't mind. I was getting ready to make a 96v pack with these exact batteries, and never even considered this as something I needed to worry about.

Thanks!

 

[blutow]

The spec sheet for the listens recommend compression. Even if it didn’t, I still would have built protective enclosures since It’s a mobile install. If I get in a wreck, I don’t want battery cells going every direction.

I think the 280 eve cells also recommended compression to maximize cycles.

 

[pau1phi11ips]

It's alive. All the core stuff is installed and running. I still haven't run the cable to the chassis battery/alternator, so the Orion B2B chargers are not connected yet.

Looks so good dude. Like how you've covered all the positive connections. It's crazy how close some people but +ve and -ve busbars, always makes me wince a bit.

I wasn't going to bother with a battery protect because the BMS can basically do the same thing. I guess it's good to have separate control of the different loads though.

 

[blutow]

It's crazy how close some people but +ve and -ve busbars, always makes me wince a bit.

100% agreement on that. I think most people are mainly thinking about the risk of shock and aren't worried about 12v since it's typically not going to hurt you. The real risk is a potential short from something getting dropped, a tool arcing, etc. I've seen too many people do unintentional arch welding on 12v systems when a tool bumps up against the positive. With proper fusing, the damage can be minimized, but it's so easy/cheap to just protect the positives and avoid it. Zip ties and bits of rubber hose, etc. can be very effective. This is also where the lynx distributer shines since the bulk of the connections are under a protective cover. Many people complain how expensive the lynx is, but it's cost competitive with other quality bus bar solutions once you add fusing. A pretty good video linked below that compares the lynx. This guy also has some other videos on the lynx system, including one on how to use the cheaper lynx "power in" and convert it to take fuses like the lynx distributer.

 

[blutow]

I wasn't going to bother with a battery protect because the BMS can basically do the same thing. I guess it's good to have separate control of the different loads though.

The battery protect is definitely an optional piece of equipment, but I like the idea of killing my "draining" DC loads while still having DC power to monitor the system, maintain power for key components, and bring things back up smoothly. In my mind, the battery BMS is a last line of defense to avoid damaging your cells, not control over system loads. I'd rather my inverter and other DC loads be smart enough to disconnect before it gets to the point of critical voltage. If the BMS kills all loads, many solar charge controllers can't start charging again without DC power from the battery (so you are stuck unless you have another battery source). If you drain your invertor capacitors, your BMS's can also struggle to start back up because they will see the invertor start up surge as a short and immediately shut back down.

 

[pau1phi11ips]

100% agreement on that. I think most people are mainly thinking about the risk of shock and aren't worried about 12v since it's typically not going to hurt you. The real risk is a potential short from something getting dropped, a tool arcing, etc. I've seen too many people do unintentional arch welding on 12v systems when a tool bumps up against the positive. With proper fusing, the damage can be minimized, but it's so easy/cheap to just protect the positives and avoid it. Zip ties and bits of rubber hose, etc. can be very effective. This is also where the lynx distributer shines since the bulk of the connections are under a protective cover. Many people complain how expensive the lynx is, but it's cost competitive with other quality bus bar solutions once you add fusing. A pretty good video linked below that compares the lynx. This guy also has some other videos on the lynx system, including one on how to use the cheaper lynx "power in" and convert it to take fuses like the lynx distributer.

That guy makes some great videos but even he is guilty of it before. WTF is this!?

I know it's gonna have a cover on the fuse but they're so close. It's just relying on the 750A fuse blowing but I think that would still make a mess and massive spark if something bridged that.

There's enough room to have the fuse along the top of the Lynx and completely out of the way of the shunt.

 

[manly]

I'm new here. Great build, enjoying following along and want to build something similar for my boat.

Newbie question for you, hope you don't mind: how is Victron monitoring the DC loads from your distribution panel? Does your system have two shunts? I see a long, skinny, small, blue box right before your DC distribution panel. Is that a Victron component for measuring your DC loads?

 

[blutow]

I'm new here. Great build, enjoying following along and want to build something similar for my boat.

Newbie question for you, hope you don't mind: how is Victron monitoring the DC loads from your distribution panel? Does your system have two shunts? I see a long, skinny, small, blue box right before your DC distribution panel. Is that a Victron component for measuring your DC loads?

Thanks. The dc load calc is a good question. The blue box is actually a "battery protect" which is programed to disconnect the DC loads (except critical system stuff) if the voltage drops too low. It doesn't measure the power in or out like a shunt.

To calculate DC load, victron basically backs into it with the cerbo device. There is a shunt right at the lynx distributor that measures current in and out of the battery. The cerbo also knows how much DC power is being produced and consumed by the Multiplus and the solar charger. Then, it does the math on the "missing" watts and that is your DC load. It works pretty well, but there is some variability when the invertor is running and solar is swinging up and down. Here's the flaw in my current system - Victron has not integrated the Orion B2B chargers into the cerbo unit (which is doing all this math). So, when the orions are charging, that flow is lumped into the DC bucket. You can't see what your actual dc load is when the orions are running unless you log into the orion chargers via bluetooth, see how much they are generating, and then do your own math to figure out the actual DC load. The orions will only be charging while driving, so It's not a huge deal, but it would be nice if they we integrated like all the other stuff. It's a common complaint, but victron hasn't said anything about when the orions might be integrated.

Following is the main screen on how the cerbo monitors the various components. I have the touch screen, but you can also access this from any device remotely through the VRM website. This is my system currently plugged into shore power and running the AC. No solar since it's night and there is very very little DC load right now. The only thing funny on the page is the batteries are not really at 100%, they got reset and are actually lower right now. You can see they are charging at 31a (which is limited whenever the AC compressor is running because I have shore power limited to 14a and the AC pulls about 10a). Once the AC turns off, the charging will jump back up to 100a.

 

[pau1phi11ips]

Here's the flaw in my current system - Victron has not integrated the Orion B2B chargers into the cerbo unit (which is doing all this math). So, when the orions are charging, that flow is lumped into the DC bucket. You can't see what your actual dc load is when the orions are running unless you log into the orion chargers via bluetooth, see how much they are generating

Great explanation, I am surprised Victron has never taken advantage of the Bluetooth on the Cerbo/CCGX to connect to the devices that only support Bluetooth for communication.

I guess the vehicle systems is still kind of an ancillary business for them though and that's mainly where the DC-DC chargers and Battery Protects are used.

 

[blutow]

Great explanation, I am surprised Victron has never taken advantage of the Bluetooth on the Cerbo/CCGX to connect to the devices that only support Bluetooth for communication.

I guess the vehicle systems is still kind of an ancillary business for them though and that's mainly where the DC-DC chargers and Battery Protects are used.

The cerbo can do some pretty sophisticated things by integration to different systems via can-bus and other digital inputs. If you have the skills, you can get into the code and display anything, write custom logic for alerts and control of other devices, etc. I don't have those skills and the cerbo does most of what I need out of the box. Maybe some day I'll dig into it a bit.

I'm sure they will add some additional capabilities through bluetooth, but I suspect it will not replace the hard wired connections to all the devices. At some point, hard wiring just makes more sense for critical systems. You don't see cars using wireless to communicate between the engine sensors and the ECU, it's just not reliable enough even if cost was similar.

Victron has a pretty good following in the aftermarket RV world, so I'm not sure I'd consider it a ancillary business for them. Also, I've seen lots of marine install examples that use the Orion chargers and the battery protect, so those seem very common on land and sea. The lack of connectivity with the Orions is really a glaring hole in a system that is otherwise very slick and easy to deploy.

 

[manly]

Thank you Blutow for that information, very helpful and makes sense to me now. Victron has so many product I'm still figuring them all out.

I notice you have 2 of the 30amp DC-DC B2B chargers. I'm guessing that is so you can charge up to 60 amps off your alternator at once? Do you have a special high output alternator you're putting in the van?

I think it's really cool you went with the 12V system and are making it work with the 3000 Watt Victron. Those cables seem incredibly beefy. I already bought two 24V Overkill BMS's, otherwise I might reconsider about keeping 12V after seeing your build.

For my system the 3000 Watt Victron is right on the edge of "what's enough" for an inverter. Their 5000 watt Quatro (24V) is over twice the price for some reason. So it makes more sense to buy 2 of the 3000 watt ones. For your loads, do you feel 3000 watts is on the high side, or just enough?

 

[Acho_303]

Please let us know how the dual orions go and if you are adding another alternator. My setup is similar but I only have one Orion and 544ah. In the winter with the espar s3 running and several days of no sun the batteries get pretty low. So I have considered adding another orion.

 

[blutow]

I notice you have 2 of the 30amp DC-DC B2B chargers. I'm guessing that is so you can charge up to 60 amps off your alternator at once? Do you have a special high output alternator you're putting in the van?

Please let us know how the dual orions go and if you are adding another alternator. My setup is similar but I only have one Orion and 544ah. In the winter with the espar s3 running and several days of no sun the batteries get pretty low. So I have considered adding another orion.

I don't have a secondary alternator on mine, but the stock alternator is 250 amps. Mercedes recommends 80a max draw to tap into the stock system and they are usually pretty conservative. The 80a recommendation also applies to their 220a alternator, so I think I have plenty of headroom with my 250a unit. I have not wired the orions in yet, so I can't speak for how often they will be pulling full capacity. I've read that the orions actually put out about 35a each and that the 30a rating is conservative.

 

[blutow]

I think it's really cool you went with the 12V system and are making it work with the 3000 Watt Victron. Those cables seem incredibly beefy. I already bought two 24V Overkill BMS's, otherwise I might reconsider about keeping 12V after seeing your build.

For my system the 3000 Watt Victron is right on the edge of "what's enough" for an inverter. Their 5000 watt Quatro (24V) is over twice the price for some reason. So it makes more sense to buy 2 of the 3000 watt ones. For your loads, do you feel 3000 watts is on the high side, or just enough?

I debated going 24v, but the high amp wire runs are so short that I didn't think it was a good trade off with the added complexity of having to convert back down to 12v for the majority of my DC loads. The biggest upside to 24v for me would have been doing 2 batteries instead of 4 (half the BMS's, save a little space, simpler wiring from the batteries, etc.

I think the 3000w inverter will be adequate for me, but time will tell. I could certainly create situations where I'm pushing it (AC, water heater, microwave, other misc), but I don't expect those to be common situations and it shouldn't be a big deal to manage loads when needed. I don't expect to be running much over 2000w continuous for any significant amount of time, and that's only when running the AC.

Make sure you are looking at the actual ratings at different operating temps on the invertors. My 3000w invertor is only rated at 2200w continuous at 105F and only 1700w continuous at 150F. I can see running into issues if I can only get 1700w out of it at times, but I don't know yet if it's going to get that hot in normal use. I plan to add lots of fans for cabinet ventilation when I build my enclosures.

 

[pau1phi11ips]

The cerbo can do some pretty sophisticated things by integration to different systems via can-bus and other digital inputs. If you have the skills, you can get into the code and display anything, write custom logic for alerts and control of other devices, etc. I don't have those skills and the cerbo does most of what I need out of the box. Maybe some day I'll dig into it a bit.

Yeah, it's a great platform. The work they're doing with Node RED looks really interesting too.

I've got my Daly BMS connected to the Cerbo via RS485/USB and Venos OS is showing some of the details from it. Pretty cool how flexible it is.