Why you need a BankManager™ for an off-grid system
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- Опубликовано: 24 авг 2024
- The first batch of BankManager™ units are available! Visit www.emilyandcl...
Well, it's finally ready. I have finished developing my Battery Bank Management System (BBMS) and BankManager™ units are finally available for purchase. At this time, I have a very limited number of units. With the global chip shortage, I'm having trouble getting enough components to easily produce more. But I'm working on it.
If you would like to learn more about this, or order a BankManager™, go to www.emilyandcl... Everything you need to know is there.
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Heading off to the Web site. I received your E-mail yesterday and went to the website but I did not exactly sit down and read everything but I will be doing that now.
This is great ! I’ve been waiting to see how these come out and they look great ! I am patiently waiting to get my hands on one .
Terrific video! You brought up an interesting point that has always concerned me about lithium with regard to off grid sailing/cabins/preppers etc. One good lightning strike or EMP hit from a solar storm (or whatever), and all of those BMS‘s are going to fail and your lithium batteries will be stone dead. Your lead acid batteries will not only survive but they won’t even notice the hit, and you’ll still have 12V power.
Thanks Mark. I later got this idea as a better way to mix the chemistries. It also seems to be the only way to not slowly kill your Li from low current overcharge damage.
www.emilyandclarksadventure.com/bbms
If course it won't survive a lightning strike any better then the li BMS but you will have that lead aboard and all wired up.
Um, if there is a Carrington Event, the rest of your electronics on board will be toast as well, that includes HF/VHF radio, Chart Plotter, GPS, you get the picture...
This seems to be a very awesome device and I hope to order a few soon when you have inventory. Great job and THANK YOU!
You could always bid the MSRP. You likely won't win this round but if I get more your bid will be in the system.
But mostly your bit will help me gauge demand. I'm just starting out in manufacturing so having orders on the books gives me more confidence to place a bigger order when I find chips.
World class presentation,thank you .Untangling the complexity ,brilliant.
Very nice device, well thought out. Strongly suggest you patent it if you haven’t already to protect against knockoffs. I have been an EE for many years I’ve never seen a product like this one.
Thanks Mark,
Yes we invented a word for what it does BBMS and a name for this BBMS, the BankManager.
Wish I knew more about selling the idea. Have to explain what it does to people first. It's not a batter mousetrap it's the concept that mice need to be trapped.
But over 100 are out there, and you just know those guys are telling other guys that it's a good idea.
And yes we have two patients pendings
@@EmilyAndClark what's the status of the product now?
We have sold over 200 of them
New model with a white case comes pre-assembled, no need to glue anything.
www.emilyandclarksadventure.com/bbms
Love your enthusiasm, get your patent pending before talking with the big boys. We know the solar will be fine, the lead-acid battery will be fine, the BankmanagerPLUS circuitry will be fine...but here's where real life installations Validation with thousands of hours (months/years of usage) will occur to make sure the Lithium will be fine, tied together. Keep a log of your battery data with the BMPlus. It's exciting doing the novel formally-forbidden designs....if it works-validated and safe....you will be a wealthy couple. Fingers crossed.
I'm excited to get one of these!
Nice! However we need to keep in mind that lithium, especially series 12V modules, need to be internally balanced. Hard stopping at 13.1V (or whatever) will inhibit the lithium bms from balancing the cells since the internal lithium bms units effectively do top of charge balancing. There are arguably benefits to elevated CV charging of lfp batteries in addition to any perceived concerns.
This method goes right up in voltage while charging as long as (at least occasionally) you charge at .3c or so.
You can always choose the charge to voltage now and again to allow for balancing if you feel it's necessary.
No need to balance every charge cycle unless the BMS has a really undersized balancing circuit.
great job with this Clark!
Thanks zen
Ive following your channel since you first started talking about bbms and so excited its finally cant wait to get the a bbmsplus and it to my system
I see your bid. Thanks
@@EmilyAndClark you're welcome i just couldn't wait i hope i win 🙏 if not its ok because since day one when you first mentioned it i already knew i was gonna buy one.
Excellent!
I knew it! Others were suggesting use of a dc/dc charger to tie in the lithium but really its a matter of separating the batteries during discharge. I have a gel cell startinig battery on an isolator switch, and its bulletproof for the heavy cranking needed with a cold diesel engine. But I need lithium to capture the output of my 400 watts of solar panels. And one 100 ah lithum and I will be in great shape but have no desire to toss out my trojan 105 house batteries. And a dc/dc charger is really not the needed component either.
No I really don't think they should be used.
There is a more elegant solution.
@@EmilyAndClark yes, only $380!
Great Job Clark, really glad to see its release!
Thanks Dan
I bought a 120$ solar charge controller, it charges the lithium. Load circuit of the charge contort charges the L.A. simplest set up you can get.
Using the load circuit for Lead isn't regulated. I'm afraid it will over charge.
There are lots of chargers out there with lithium settings. I haven't found one that doesn't overcharge at low current.
Simple but hard on your batteries.
👉🚐👍 Your walk through is ideal because all your components are clearly visible as you go through the system step by step. 👍
Thanks Dennis
@@EmilyAndClark I did a look at the order page, using PayPal is a real plus for me and and also not billing till you ship. Now if I order can everything ‘that is needed” be included in the kit? What do I need happen so this install would be a walk through with you? I just installed a SoftStart on my air conditioner and that was a walk through with them. So what do I need to do on my end to order and do a 1 on 1 with you? Typing this on my IPad 🥴 hope it’s understandable! 👉🚐👍 Later
Well for FULL service you should buy the BankManagerPlus and the contactor assuming your system uses below 200 amps. If you use or charge over 200 talk with me as I can set them up bigger but all that is in the order form.
Then if you want the max hand holding go to Patreon and sign up at the "Dream Believers" tier and you will get my cell phone number. We will make this and anything else you want to chat about work.
Very nice ,now here comes the however . Everything on my boat is UL, ULC ,ETL, CSA certified . Is yours? If not if any malfunction were to happen such as clamping the 2 systems together , high amp flow and a fire , insurance will walk.
Yep looking into that. I believe I've met the requirements but for now this is only for those willing to experiment with me. No stickers yet.
After a round or two of selling it I might sell the idea to a big player (there have been talks). They will deal with that.
Nice Video! I think I finally am starting to understand what your system does. Now I need to go back and watch your original Lead vs Lithium videos....again. However, just to make sure: This system would still work with the "Little Lead and Lots of Lithium scenario"?
Yes. From that to the little lithium and lots of lead. As long as you have a bit of each.
One car battery should be plenty.
Looking forward to when these are available
Watch to the end, or read the description. They are available now.
Hallo, ich freue mich sehr über Eure Fortschritte in der Entwicklung dieser großartigen Technologie. Bisher habe ich nichts gleichwertiges auf dem Markt gefunden, außer einem kostspieligen Lithium-Komplettsystem. Ich bin sehr interessiert, das BBMS Plus zu erwerben.
Thanks, I hope you can get one.
Avoid interrupting charging based on SOC because if charging takes place with a high current and this is suddenly interrupted at e.g. SOC 90% then there will be an arc in the relay that can damage. In addition, voltage spikes also occur at high charging current which can damage chargers that are connected, which especially applies to alternators where the diodes can be smoked.
Good point. If high charging amps are being used best to charge to 100% setting.
Best to charge to 100% anyway in my opinion.
When charging with solar usually amps are reasonable for switching.
And remember the lead is always there to take transient spikes.
Interrupting charging with a relay when high current (> 30 A) is not a good idea, even if starter / aux battery should alleviates the effect of load dump. If you have to interrupt charging at e.g. SOC 90%, the charger must be controlled directly (remote).
Please back up that statement. For example how is a solar controller going to be damaged by the lithium switching out at 30 amps
How is that different than a 30 amp load suddenly going away?
Do I need to stop using my microwave?
Your question surprises me. It's not about chargers or consumers suddenly shutting down. It is about a relay or switch interrupting high current.
If you run a 3 kW inverter for Micro, you can continue with it if the lithium batteries or rather mosfets can handle the power.
Note that lithium battery can handle very high current (much higher than lead) but there is a limitation in drop-in batteries such as. Battle Born. This type of battery does not have a mechanical relay but a semiconductor (mosfet) that the high current passes on the circuit board inside the battery. The mosfet gets hot from high current, which can shorten its life and if it fails, the battery is switched off. Then it is good to have lead and opportunity to force connection as backup...
You brought up chargers in your first comment.
I assure you that our recommended contactors are up to the challenge. And I chose that approach over MOSFETs for very good engineering reasons.
The only lithium problem I have is early disconnect due to one of the 8 cells shutting down the pack , before the low voltage shut down of UPS inverters and solar charge controllers. Both say to never disconnect battery hen in use. Can you design a super capacitor that will slowly discharge to the 10.5/21 VOLT auto shutdown voltage of UPS inverters and solar charge controllers. Far less complicated than this great piece of safety equipment you have here.
Give it a shot. Capacitors bring their own problems.
@@EmilyAndClark thanks anyway.
Hi, I am really enjoying your projects, I would also like to look at a boat rewire project. Is it possible to set an over voltage cut off on the bank manager plus to protect the cells from solar controller failure?
Yes. Built in. Though this really the BMS's job, if voltage ever goes over 14.6v (for 12v) the li is disconnected.
Also, just normal BBMS operation, it disconnects the Li once it's fully charged. This should always happen before the solar regulators cut out in it's efforts to charge up your lead.
In short if your solar regulator faulted "ON" the lithium wouldn't even know and would just run as normal.
You're lead would be overcharged though.
should I use a DC to DC charge controller from the alternator power source to charge the battery bank with the BBMS to keep the LiFePo4 battery in the bank from drawing to much current from the alternator and overheating the alternator when it starts charging if I use the engine first thing in the morning with low battery bank current before the solar system has a chance to start charging the system?
No. I talk about this in one of the videos.
I think you should solve that problem by using an alternator regulator with a temperature sensor on the alternator case.
The other issue (BMS cutting out and destroying your alternator diodes) is solved by the bbms concept. Lead is always there to absorb energy.
And Parallel Capicitors into the Battery Bus for really quick charging from your Solar Panels ?
No. Stay away from the line of reasoning.
It causes so many more problems then it solves.
1 12v pb for starter and 8 12 parallel lipo4 means everything 12v, I think, thimk, whaterver.
Yep
Hi Clark - if the lithium is connected when we want to start the engine, will the lithium end up contributing the majority of the starting current or will the load be shared?
Usually shared. As the large load of the starter will bring the surface voltage of the li down below 12.8 where lead starts contributing.
If you have special circumstances like tiny li and huge engine you can set a max discharge limit in the BankManager. If it's exceeded the BankManager will disconnect. Your engine will start on lead. Then once your alternator brings the lead voltage up the BankManager reconnects.
I love your system. I will be ordering one. One question, can I use your battery manager if my lithium batteries are a 48 volt system ( for a 48 volt electric motor) ?
No problem. We have sold several to 48v off grid houses. They seem happy.
Is this for an electric boat? Did you see my Duffy video?
@@EmilyAndClark yes, I follow him also. Mine is a 6 ton sailboat. I'm currently removing the diesel and prepping for the electric motor and new lithium to complement the AGM.
I always wanted to do that to Temptress. But last time I repowered I realized I seldom motor but when I do it's often for days on end. For me diesel was still the answer.
But I love the idea of electric.
I think a less technical and more sales oriented video might be a good idea not that this one is bad of course. But a simpler video with example setups and benefits might be a good idea. I would make some slides of real world examples like... if you have 400AH lead and you add 100AH lithium then it will do this... if you have 800AH lead you add 100AH it will do this... If you have 800 AH lead and add 400 AH lithium it does this... and maybe a few more so everyone can relate it to their situation. I'm surprised you didn't use the ram cache/buffer analogy! But then I wonder how much lithium do you have to add to benefit from it as a buffer. And then I wonder if it really does that at all since I'm just benefitting from whatever Lithium AH that I've added. I mean sure you can dump the faster power into the lead once the sun goes done but you could just use it directly off the lithium so it's not really a buffer just a convenient combiner to avoid having to swap power sources. I don't know and just letting you know what might confuse people even like me who have a little experience in electronics and programming. Best of luck!
Thanks. If that happens I'm going to have Emily do it. I do the technical descriptions as I'm the one who developed them. But she is smoother on camera and much prettier.
@@EmilyAndClark The Emily who does budget review might be better at it than regular Emily, they must be twins! :)
Hi Clark, I'm thinking your BBMS and BMS would also be great on a RV and if so you should mention it. Cheers André
Yes. RV and off grid houses are ordering them. One guy is putting one in his semi truck.
I expect it will catch on. It seems to be the only device that can safely charge Lifepo4 to 100% full and not over charge.
Lithium can die in a couple of years by being charged to voltage. Even if the voltage is relatively low.
Hi,I plan to buy SOK LFP Marine batteries at 206 AH. Will I be able to set my BBMS for that exact capacity ,or will I have to set the thing for a 210 AH and charge at 98%.
You will have to set it for 210ah but I think the way it works you will likely charge to something like 99.5%.
The math isn't linear.
In short I really don't think you will notice the difference.
There is a new battery out there near are you aware it's a carbon lid battery and it exhibits the same characteristics as a lithium iron phosphate is faster charging has lower internal resistance I wonder how that will pair with the lifepo4 they said it would be more cost-effective but I found it to be more like on par with lithium iron phosphate cuz I was really hoping it would be cheaper boy would it be
I said it was a carbon lid l e a d battery but Google stinks so badly that it thought I said l i d
It pairs just the same.
Did some studies on it last year.
Assuming it's still more expensive then regular lead I'd probably stick with agm or floodeds and wait a few years to see how it holds up in the field as your Lifepo4 will gladly do what the carbon lead is suppose to be good at.
I love what you've done with the BBMS. I have a desire to run my 120v A/C via my 2000w invertor while underway. I'll have a 120A draw from the A/C, a 200A BMS, and a 100A alternator. What in the BBMS protects the alternator? Is the answer the same if I opted to upgrade the alternator to 150A?
I'm prepping a video on that very topic.
In short total protection for diodes and electronics from voltage surge on BMS disconnect
The overheating won't effect most and can be addressed for the rest.
......video
Clark, again, I think the BBMS is genius. Once I get back to my boat and check my battery compartment size, I'm confident that I'll be ordering one. I have one question though, I may be missing something in your example of a daily cycle of usage and charging. Let's assume that your solar panels have charged the lithium for the day and the BBMS initiates a disconnect and the sun sets shortly thereafter and charging ends. Load is drawing the lead down and no connect of lithium will be initiated as the lead voltage continues to drop. So, you're heading into the night with the lithium is disconnected. I don't see this as an issue, just that you still need to be aware of the state of the system (ie connected or not). At this point I assume the quickest resolution is to add addition charge to the lead and/or remove some load to force a connect?
Simpler then that
When the lead voltage crosses the li voltage on its way down the BankManager reconnects the li.
I keep watching and rewatching this video trying to figure something out... the lithium batteries i have are the big battery owl max 2 the are an encased battery with no acces to the terminal they use an Anderson connector. right now i have two of those batteries connected to bus bars could the device positive cable for the lithium be connected there and for positive lead cable coming from the device could connect directly to the terminal of the lead batteries but than does lead positive and negative connect to those same bus bars i hope that makes sense. (After watching again) oooooh i think i see it would be lithium battery -->device -->busbar -->inverter
Lead would be the same lead-->device-->busbar-->inverter
Than then the lithium would have the holofex sensor on its positive would it matter that lithium is higher then lead though i have about 460ah of lithium and about 200ah lead.
Sorry I didn't understand your question.
Try this, I just finished the manual.
www.emilyandclarksadventure.com/bankmanager
@@EmilyAndClark i think that answer my question basically the lithium batteries i have are fully enclosed in a steel case they are designed with a specialized cable one end has the Anderson connector the other end has ring terminals which contact at the bus bar but i think i just connect the those batteries to the contactor than from the contactor to the bus bars
Yes. That's right.
@@EmilyAndClark ok awesome thank you. I was just overthinking it because the example you used your lithium you had direct access to its terminals but like i said mine is a little different with the whole plug thing but cool it will still work
I understand the BBMS won't connect lead and lifpo while there is a large difference in state of charge. How would this work on my small engine-only starting battery? Is there any way you can think of that my very small AGM start battery could drift so low it would not ever get reconnected to LifPo to bring it back up? With 640 watts of solar (on 4 separate MPPTs) maybe I should just dedicate my alternator to 'only' my start battery? Or, probably should get a LifePo regulator for my start battery too then it's a non-issue. Your thoughts anyone?
It shouldn't be an issue.
I wish I could end with that comment but I just got a message from a user who has been happily running his BankManagerPlus for months but today had a failure to reconnect.
It's a cloudy charging day and his lead is small. I'll look into this and make some modifications to the code for later units. I happen to be headed to Wisconsin so I'll address this in the inventory there.
Since this is the first time I've heard this with 100 units sold and all our test days I'm thinking it's a rare occurrence.
Clark do I need an additional unit for controlling my onboard shore powered charger as well????
Nope. Just this and Li added to what works now. Any number of chargers are fine. It will still only follow the first charging curve until the Li is discharged a bit so your charging sources don't need to communicate.
How do i do the 1 12v pb and couple 48v lipo4 setup ?
You don't. Sorry.
Technically you can with a buck boost converter but that is wasteful and awkward.
Either stick with 12v or change out your starter and go higher. (Assuming that's why you want the 12v battery)
Can the BBM+ also be used when charging with the ship alternator? I do not see why it shuoldn't but thought I would ask the question.
The BankManager doesn't care where the charge comes from.
In fact the BankManager approach protects your alternator's diodes.
Thanks for the quick reply. I read further down in the comments that the BankManagerPlus is also a better option than a DC/DC charger.
Once I get my battery system where it needs to be, I will be ready to get your boat AC also.
I just put together the first air cooled version for my parents camper.
Works great there as well.
You are going to like it. It's really a game changer. Battery AC in the tropics!
@@EmilyAndClark I have a sportfisher in Fort Lauderdale. The onboard AC works when at the dock, but I like to run over to the Bahamas and anchor out. I dont run my generator over there just to power the AC, so my wife isn't as big of a fan of overnighting during the summer. I plan to work out the battery system to be able to power an AC for the forward berth and a second one for a small aft berth for overnight cooling.
I'm not looking for multiple days of usage without charging (I expect to charge the batteries while I am fishing and the engines running), , so my battery bank would be relatively small.
How much is the bank manager and will you ship to the UK?
Purchase information is here. www.emilyandclarksadventure.com/bbms
We can ship directly to UK but we can't provide tracking or insurance. So you have to just order and hope for the best.
Some international buyers are using reship.com to get a US address. Then we can send a tracked and insured parcel to then. You get it from them however you like.
Probably simpler to just do 12 v with lipo4 parallel at 12.
Sorry I didn't understand
Can you use the BBMS with AGM, and Lead ACID batteries combined ?
Yes.
I have flooded and AGM on my lead side
Thoughts on power inputs and loads arranged to both connected to the lead side? Likely have to re-watch some of your prior episodes on lead-lithium, doubtless you answered questions there. Possible you have additional thoughts with so much time and collaboration.
I will be next to starting from scratch since my 2x 8D agm are worthless and next to worthless.
Yes as I say in the first video you need to do this with healthy lead.
I don't think I understand your question. I have a bit of a block wiring diagram in last months video. But, yes I expect your loads and charging sources to be connected to the lead side. If you connect anything to the lithium side precautions need to be followed as that could likely screw with my calibration of the current meter.
@@EmilyAndClark Re-watching the lithium-lead episodes in your capable cruising. So it seams to be as simple as lithium attatched to a traditional lead system with one relay controlled by bbms. Hopefully I have it thoroughly straight.
Yep, that's it. You got it. I say it's a switch with a trained monkey.
But the monkey had to get really smart for the plus. Multidimensional math and forecasting.
But just a trained monkey and a switch.
When using engine alternator or alternators, because of the high bulk consumption lithium has over LED acid , typically unless you have a smart alternator you'll need to run your alternator output through a DC to DC charger so as to protect the alternator at low RPM from over heating . Does this device eliminate the need for a DC to DC charger ?
There are two ways lithium can damage an alternator. This approach protects from the fairly common diode destruction caused by BMS cutting out during high current charging.
The overheating you mention (and obviously have a good understanding of-most people don't understand it happens at moderate to low RPMs) isn't addressed by this method. But it can be easily addressed by using a regulator with a temperature probe.
If that isn't practice it's really simple to make one. Use a thermal switch on the alternator case that controls (with a relay if necessary) the field coil. With this, the alternator will shit down periodically when it gets hot.
@@EmilyAndClark wow ,quick response ,very impressed thank you very much for the info . You just my subscription.
@@EmilyAndClark ok one more question ,can you just continue using the DC to DC charger to the lithium ?
@@EmilyAndClark oh and Dove and Rebecca say hi ,there friends of mine here Carricou,there beginning to install your BBMS system .
Since you know about my bbms system I'll answer in terms of that.
The DC-DC approach is always inefficient. Expect a 20% loss on all the power you pump through it. Think of having 20% more room solar panels!
They (like virtually everything else besides my BankManagerPlus) use a voltage cut off to regulate charging. This would be fine for lead. It KILLS lithium.
They can only pass power in one direction.
The only use I have found on Temptress is to charge my portable li battery that we use to power Emily's little boat. It was a practice way to limit current between flat li and full li. But I had to build my own control circuit to have it work safely so in short I see them as useless. In fact that's what I designed the BankManagerPlus to replace.
I'm going to ask a question that most likely only a ham would ask. It involves this device and any other devices and noise on SSB.
I need to get a couple of MPPT charger/controllers, as I have several 36 cell panels and one which I believe is 72 cells and a bunch of power, almost 400 watts. I would like , if affordable , chargers which are MPPT and yet do not have noise on SSB HF. (of course, they would not have noise on VHF if they were quiet on SSB ?) . Any suggestions ?
You know I haven't fired up my radio in years. Not since I installed my mppts. They are switching a load of current through a coil and long wires at what I think is about 20kHz. Could be a real problem.
I'm just a few hectic days from a trip or I'd turn on the radio and listen for you.
For what it's worth, I use EpEver controllers. Cheapish.
If you are referring to my BankManagerPlus
www.emilyandclarksadventure.com/bbms
It only switches about 20ma with really short leads and a tiny coil in it's power supple as well as a rather slow microprocessor chip so I'd expect it to be quite clean.
You could always wrap the box in foil of course. It won't get hot with a bi-stable contactor attached.
@@EmilyAndClark I knew you would answer because your hoping to market that item. That said, I was hoping you could share what you've heard about MPPT charger controllers on the market as I need to choose one and I'd like it to be a somewhat quiet one. Perhaps you don't use mppt ?
As I said above we use EpEver units. They don't react to clouds as fast as others but they are less expensive and can handle shorter strings of panels.
I like short (low voltage) strings of panels on sailboats because we have masts and rigging that is always shadowing something.
We aren't hoping to sell these we have sold a whole bunch of them. I have a new batch headed to Wisconsin now. Should be ready to ship out in about 2 or 3 weeks.
Clark. KD7ENJ
@@EmilyAndClark Great, thanks, I'll look into the EpEver MPPT controller. I would have gone with a bunch more 36 cell panels had I needed to buy them , and may still if I have room. The huge one was gifted, and is more suitable for a house.
When you say lead, does that also include
Lead does that also include AGM and Gel?
Yes. I personally use AGM on Temptress. For gel you need chargers that can safely charge gel but no worries. This should work fine with gels. (Some not so great BMSs might need to balance at a higher voltage then gels like so you might have to switch off your gels occasionally to manually balance your Li but a good set of cells shouldn't need too balance very often)
Works with lead carbon foam as well.
Just curious, what is the difference between your system and say a battery isolator ment for lithium? What does it do differently? I saw on a forum that you were originally planning on sharing your circuit with some of the DIY group but cannot find it anywhere. Understandable since you are selling it but I have some concerns after alot of research and without seeing your circuit diagram it would be difficult to trust if these concerns were being delt with. A simple example would be is there protection from OC In case of a cell short on the lead acid side? Thank in advance. Apologies if I missed the answer to my questions in a previous video as my data is very limited while cruising ATM. Cheers.
No you haven't missed anything. I've not yet done a proper "sales" video for the thing. We sell out each batch very quickly and I can't find the chips to make new ones much of the time so I've let that slide and accept that I'm only selling to guys that can basically reverse engineer it.
Best source is the manuals on the sales page. www.emilyandclarksadventure.com/bbms
Most of this is microprocessor driven and all the tricks are in software so a schematic wouldn't help you much. But I'm proud to say that one of our Patrons is a high end board designer. And after reviewing my grib files he said that my layout was very good and all should work as planned (he then placed an order).
As to your specific question. There is a parameter you can set that defines the maximum current the li is allowed to supply before it is switched off. This is for removing a small li bank from large loads (engine starting in an RV) but works as a "fuse" if you had a lead battery go south or just a short circuit.
@@EmilyAndClark thanks for your quick response. That makes sense. Considering lithium has such a flat discharge/charge curve how are you programming your set points? Wouldn't voltage alone be a tricky variable to use? Best of luck with your sales.
You need voltage current and time in the equation to make it work.
Clark, it is possible to easily program a battery monitor (eg Victron BMV) to control a relay that switches on / off based on SOC, Voltage and time delay. There is also on the market AVR (voltage relay) with lithium setting that combines lithium and lead based on voltage. There is also an external X2 BMS on the market with X2 technology, where X2 stands for combining lithium and lead. This is the only BMS on the market that combines lithium and lead in a safe and correct way and also regulates the charge of lithium.
Yes. That's basically my base unit technology.
The plus does that and so much more.
Do more than what?
Your bank manager works as a battery combiner and also charge management, ie disconnects lithium when it is full.
We have sold exactly such a system from 2017 until 2019. We then used Victron Argofet or Victron CyrixLi + Victron BMV712. From 2020, we have sold X2 BMS (instead of Victron items) which is specially developed for boats and to combine lithium and lead. The algorithm that controls the X2 combination has 50 conditions which also include conditions about cell voltage.
I just want to inform, because you claim that you have invented something unique.
How does your approach detect POC?
I don't see a current sensor watching the lithium battery in your block diagram. I have found that voltage alone isn't sufficient. Over charging of cells can happen at voltages as low as 3.37v (13.48v at 12v) and low current charging.
But good to see other people working on the idea of mixing these two chemistries.
What is POC? Maybe not Piece of Cake ...
There are other ways than using a current sensor and that is by creating an algorithm that does not open the relay when charging current is running and at the same time the voltage is low (ie the battery has a low status). If your question specifically refers to the X2 BMS, the BMS understands if charging and will not interrupt at low voltage. Moreover, the battery monitor (Victron BMV712) can be connected and control charger via remote together with the X2 BMS's protection functions for high cell voltage and temperature.
You may apologize, but what you say about voltage is not correct.
The voltage does not determine the charged status, and a cell will never be overcharged nor fully charged at 3.37 V.
There are advantages to mixing lithium and lead (backup, pre-charge, load dump and others). However, I would like to add that the advantage of mixing lithium and lead is not by also cycling the lead battery.
I have seen that you claim this but the problem is that if you first discharge lithium and then discharge lead, there is a clear risk that the lead battery is not fully charged to 100% and therefore premature aging.
After lithium is discharged to 20% and then lead is discharged to 50%, charging will take place to lithium first and then to lead. The problem is because lead will not always be fully charged because it takes a very long time when has been deep discharged. The charge of lead also deteriorates when a lower charging voltage for lithium is used, but if the charging voltage for lead is used, it is not completely optimal for lithium.
The system that X2 BMS recommends does not normally cycle the lead battery and then charging voltage works to combine for both batteries.
I see you don't yet understand how my recommended charge cycle works. I guess I wasn't clear. But maybe you could watch again. Lead in my system does get fully charged. In fact from the lead batteries point if view there basically is no lithium.
As for need to monitor current I suggest you read this.
nordkyndesign.com/charging-marine-lithium-battery-banks/
He expressed it much better then I. I particularly suggest you read the "charge termination condition" section.
If your goal here is a mutual better understanding if the problem then after you look into this I'm happy to keep talking.
If your goal is to increase your sales of an the product you sell by trolling. Well I don't feed trolls.
To bad, it's not available in Europe yet.
If you can arrange a mail forwarder you can get one. We use one to get all the parts here to the Dominican Republic.
I know some bidders that are doing that.
Just get a friend, in the states, to buy one and ship it to you. Easy to circumvent distance.
Thanks for the suggestion, but I don't know anyone in the states, and I don't know much about mail paper works.
With blind auction, I'm not sure.
Maybe one day, Emily & Clark will determine a fixed price and will be able to send it here, in Belgium.
Cheers.
I Hope, there will be a possibility to ship one to Germany next year…
I've already gotten two bids from people using a mail forwarder.
"Easy Cargo
1970 NW 82nd Ave
Miami, Fl 33126
Seems to be a forwarding service.
I'm thinking you have seen this young fella's video's.
how does your system/research compensate for the hazards he points out, 13:08 i think is the time stamp, hazards of broken plates, etc on lead acid tied into a lithium array.
ruclips.net/video/oXBT8lSC25M/видео.html
Well I don't use MOSFETs to control current. There are advantages but it's safer and more efficient to use a contactor.
The latest version of the BankManagerPlus has a setting for the maximum current out of the li bank. If anything causes more current then the setting the li is disconnected. I'd always set this slightly lower then the BMS shutoff and any fuses you use.
Besides safety this feature is useful if your Li bank is small and you have a very large load like engine starting.
But of course if you have a shorted out cell or even a dead wiring short this will disconnect your lithium.
By the way. I had a starter battery short. I'm my case it took days to discharge my 200ah of li and 1500ah of other lead.
It was pretty uneventful except I had to charge everything back up and a cupboard got really hot.
@@EmilyAndClark I like your detailed (educational) responses, thank you
I'm not familiar with the term mosfet, I suppose i should look that up. possibly something i know under a different name.
I'll be upgrading 330 watts solar to 8 or 1200. not sure if to stop at 3 or 400 ah lithium or go for 600. and I'll probably keep the lead i have. (we'll see, dime store, aka walmart, junk, but near new) 5 of them, counting the starting battery and the genset starting battery.
i'll most likely be emailing you. (after i get the new emails set up).
what's the lead time, to order 1 or 2 of those?
MOSFETs are fancy transistors. It's what he refers to as FETs.
I might have product in Wisconsin in about two or three weeks. I have orders in the pipeline. I didn't invoice until I have product to ship.
Clark...... maybe a new simplified way to describe the bbms.
BBMS is the bartender that keeps serving you (lead battery) from the bar cooler (lithium bank) as you consume beer at night at night........ and in the morning bartender (BBMS) manages restocking things..... while treating you (lead battery) for a hangover. Snap!
PS: think that emoji is snapping its fingers and not shooting a bird lol"
Reply
sent you an email for more in depth questions... still wrapping my head around some stuff.
What is your email address?
@@EmilyAndClark same as my username here... coachgeo (at) etc etc. Have BBMS Plus model so should be in your message archives.
Yep. I responded