Thanks for the report Kevin, Glad it's working so well for you.

Last I checked Dave was just selling a voltage sensitive relay as a BBMS. No safeties about connecting charged with discharged banks (fire risk) and no logic to properly charge your lithium (low current overcharge death) Careful

Thank you Mike

Thanks Tracy

Will do Thero And please share links with your friends.

Your welcome, John

I'll keep cutting the answer in half until I don't get questions. Once you understand something it's hard to know what "dose" of new knowledge is too much at once.

You're welcome Jason. Glad you are enjoying our work.

Thanks

Thanks Ken

You're welcome

You're very welcome

You're very welcome. Have you watched our other videos. We have a playlist full of electrical videos

You're very welcome

Thanks Bill

I guess I might not have explicitly said it by any charge offered to either of the lead batteries will eventually be shared with all three batteries. If you are referring to damage to the alternator caused by heavy charging I covered that in kzfaq.info/get/bejne/oKmKmcRj15O1fY0.html

And thank you

Thanks Alan

Thanks Len

You're welcome

Thanks

Sure stop by. But get your fishing in before you get here. The DR is pretty overfished. Not much here.

@@EmilyAndClark I will.

Might have to go out for a day trip. It's the ocean lots of fish out there lol

Lots of fishermen here. They go to the Bahamas to steal fish. I understand it like a fish dessert around here.

@@EmilyAndClark really weird. Have to figure that out.

I like the dial sensing versions. kzfaq.info/get/bejne/p8mboNVnss21c6c.html That way any charge current gets shared everywhere. You can leave your alternator charging through your starter wire and your li will float your starter batteries for the longest life.

Yes, more than a single KZfaq video for sure

You could watch our old boat tour video. I think we should redo that. A lot has changed

@@EmilyAndClark I think I have watched all your videos. I will slide back through the history and make sure. You should never struggle to find content with your skills. -God bless.

Thanks for spreading the word. I really enjoyed my time in Puerto Vallarta. Do cruisers still hang out at los Crusis? And I really hope you spent some quality boobie time at isla Isabella!

@@EmilyAndClark Yes, I am anchored at La Cruz awaiting a haul out to make a necessary "do it now repair". It is a great little village that sees the majority of the cruisers heading to French Poly and other points W and S stop, load up and wait for the trades to build. The anchorage sucks though and teaches one how let go of their needs for comfort while on anchor. I typically don't spend more than a few days here, my haul out date has me waiting a month on anchor with no engine. Do not come to Banderas Bay for a haul out. My 37' monohull fee is $1050, plus $50/day while on the hard, cannot sleep on the boat. I have been to Isla Isabel five times in the last 2 1/2 years, it is glorious. I am simply amazed at how many cruisers will not go there due to the little bit of extra finesse it takes to anchor between the boulders that are known to want to keep anchors.

Thanks.

Might I suggest this playlists? ELECTRICITY ON BOATS - Clark's Full Masterclass: kzfaq.info/sun/PLsT7_jPsZM5ogT6or244F49-Gy7pYFV7V

I guess I don't understand your approach. You do this every charge cycle? With discharge deactivated what happens when the charge source isn't large enough to handle a big electrical load? Won't system voltage crash? Oh, I guess you use lead for big loads while charging. How do you deal with the "low current overcharge" issue of the lithium. If you don't remove the li from elevated voltage after it saturates how do you keep it from being damaged? Do you deactivate the BMS charge capability? Could work.

@@EmilyAndClark no, you would only do this initially. Once the two voltages are the same, you enable the discharge again and don't ever have to turn it off again (unless you ever run the batteries below 10V, which isn't great). I'm also assuming there's no charging source that charges at over 14.6V. As for the low current overcharge that some people say damages lithium cells at voltages as low as 3.5V, I haven't seen any evidence of that.

We have seen batteries that were charged to only 13.8 but held there past saturation die in 3 years of use.

@@EmilyAndClark I'm defintiely not saying you're wrong, but I have not personally seen this with any of our batteries. How did they die out of interest? Did they just lose capacity? Did they get bloated? Did they start leaking?

Honestly I haven't personally seen that battery but my friend Conrad has been following this a lot over the years and showed a link to me from a reputable seeming guy back during the beginning of this project. I think it was nordkyndesign.com/charging-marine-lithium-battery-banks/ It should be linked to Conrad's writeup at the bottom of this page www.emilyandclarksadventure.com/bbms From my memory it was prismatic and I believe they swelled.

Thanks Joe

Doesn't matter. Basically put the switch in parallel with the VSR. Switch on - hard on Switch off - auto control Switch off and VSR ground wire switch off - hard off

No ratio but minimums. Sadly the minimums aren't rules but system dependent do no easy answers. Enough Li to get through the night. Enough lead to keep your charge controllers sane and to not have the system voltage crash when your biggest load is put on them alone.

That is correct

1. I use Vaseline for lead batteries. Always have. I've had no issues. I like conductive grease. I go into that in detail in a video, probably the terminal one. 2 what's a BIRD 3 No idea. Never owned one that I know of. The BankManager works fine with monostable relays as well. As long as that one is rated for enough switching current and it doesn't use too much coil current AND is continuous duty it should work I expect. (I'm stocking some $100 monostable Chinese relays rated for 500 (Chinese) amps. They have a built in economizer. They are in stock but not on the "buy" page yet. Also I have a few huge automotive style 250a rated monostable I'd sell for $50 if any of that makes things easier. )

@@EmilyAndClark A BIRD is a Bi-directional Isolator Relay Device which I think performs the same function as the Voltage Sensitive Relay you were talking about but I'm not sure. The reason I ask is I'm pretty sure I already have one installed in my motor home. Being the cheapskate that I am I have spending money for something I already own. Here's a link to some literature. 8hi01e.a2cdn1.secureserver.net/wp-content/uploads/2022/02/53-00362-000-PRODUCT-BROCHURE-1.pdf

That's one of the reasons, Ben. kzfaq.info/get/bejne/oKmKmcRj15O1fY0.html I really think dc-dc chargers solve two problems but introduce like 4 more.

Noticed that also.

But my dining room table isn't negative ground. :)

Except there are no decent dc-dc chargers. They all charge your Li like lead, to a voltage. If you want long life you need a BankManager.

Either. Or both. Generally the smart money goes on the li side

No problem Our boat has 1500ah of lead, and then there is this.. kzfaq.info/get/bejne/pb1nesWKuZnTk6M.html

No because for this scheme to work some lead has to be guaranteed to always be connected or bad things will happen to your charge controllers. But with a hybrid battery system you really don't need the VSR as much. Since your lead won't really be touched until your li is nearly dead you can use a thin plate starting battery as your lead bank (in fact I recommend it) as it won't cycle much. Just don't let the li go dead and all is well. So in terms of the video, use the two battery model with the lead being a starter battery.

@@EmilyAndClark Thanks so much!!

Well I obviously like the BankManager. www.emilyandclarksadventure.com/bbms

There is this. www.emilyandclarksadventure.com/bbms

There is a minimum. No maximum really except a lot of sick lead will eat power over night being held to 13.2. The minimum is: 1 enough to keep your charge controllers sane. Some make bad decisions or put our really noisy power if connected to small batteries 2 enough to keep the voltage from dropping too fast when a big load comes on with the li disconnected. It's very system specific. Thin plate starter batteries do this job best as long as you don't plan on cycling them. If you are planning on using your lead as a cloudy day backup you will need this plate deep cycle batteries but you will likely want a good amount

Only one difference. VSRs cost $25 bucks Battery combiners are like $200

@@EmilyAndClark You are very correct on price. I have the victron one....

Yep. I added a special feature so the li gets disconnected when you start your engine automatically so the li isn't asked to do that heavy lifting. Comes back in when the alternator starts charging. With the BankManager you can correctly charge your Li battery off the cars charging system.

I think you are missing some things First off if you treat lead the way the BankManager does and it will last a really long time. Li has BMSs inside and for most users they are beyond magic. Get hit by lightning expect them to die. Expect the BankManager to die but a big vat of lead and acid, expect them to live. The ISO just asked Emily and I to write a white paper that will be the beginning of their standard on the subject. They are taking this seriously. ABYC states if you use Li you "shall" have a reliable backup power supply for critical systems. (Lead) Many issues with alternators. Many other advantages. Watch through our stuff and read www.emilyandclarksadventure.com/bbms If it interests you.

​@@EmilyAndClark Thanks for coming back. Really enjoy your videos and love what you are doing. Sure. The lead will last longer if you effectively don't use it. But from the POV of someone putting in Lithium they are almost certainly doing that when their house lead is almost dead, and they probably putting the lithium into the same box where that dead lead is coming out. They will probably triple their usable capacity by switching to lithium, in the same space and with less weight. Firstly, I am not arguing for a pure Lithium system. Lithium is not very good at extreme currents (despite what some new "starter lithiums" now say). So yes, you should still have lead. But IMHO for a simple and effective system, you should just have starter/windlass/bowthruster lead, and NOT house lead. The amount of lead you thus need is very limited, because it is not about capacity, only about max current. Lead is good at that. And you just park it literally.. with a manual switch or with a voltage sensitive relay as you have shown. Secondly, in terms of "backup systems and failing BMS": Yeah that's an issue. but these have much simpler solutions. Have a way of bypassing your BMS. Building your own LiFePO4 instead of those pre-made blocks helps here, but is not required. And/Or have spare BMS, they are relatively cheap compared to the actual battery. And/or have way of switching your starter lead into your house circuit (a simple high current bypass for the voltage sensitive relay). In this case, you will have enough to run essential nav instruments, VHF radio etc. The issue with alternators should be addressed by having lithium compatible regulator or charge limiters (I think these are lame), but in my suggestion they will always have the starter/windlass/bowthruster lead to dump into and regulate off (no spiked diodes when BMS cuts out etc). I think I have read and watched all your Bank Manager content. It's very clever and it looks like a very neat and well made unit. But for me it still seems to be predicated on the need for using LiFePO4 and lead as house batteries in parallel for the "normal use case" (ie not emergency fallback). And I fail to see why that necessary or even what advantage it has. I think you are asking people to keep 2 types of house battery and the space and weight allowance for them and then asking people to buy a very good and clever product to manage that situation. But IMHO you have not explained well, why people would want to do that in the first place.

Also, The "on line" lead was the only way I could solve the low current overcharge issue that every "Li compatible" charge controller out there causes. See Conrad's article at the bottom of this page www.emilyandclarksadventure.com/bbms

​@@EmilyAndClark OK, just read that. In my book it is the Lithium BMS's job to stop overcharge. It can do that. Conrad says "this is the ejector seat". Correct. No regulator is supposed to detect that. It's at the cell level. However, is it not true that in any net charging situation the starter/windlass/bowthruster/BUFFER battery battery will be connected via the voltage sensitive relay? So the lead can act as the buffer for the solar / wind / alternator regulators. The house consumers would will be directly fed from charge. There is no lead capacity needed for this. Therefore no lead house battery is required? If I am missing something on the above "situation at full Lithium" with BMS cut off, and you think the solution is a lead house bank, then I think it might be worthwhile making that case more clearly to motivate people to reserve the space, weight and cost of an additional permanently connected lead house bank with significant capacity. (and then use your product to manage the charge / discharge in parallel with the lithium) What is much better than the "integrated 12V block LIFePO4 with integrated BMS" is a proper separate BMS with separate charge and discharge contactors which the BMS can separately control. ie when the Li if full just switch off charging to Li, not discharge.

You seem set on your position. We are all captains of our own ships. Do as you like There are pretty good advantages in this approach hundreds of people are using this approach to good effect. It's being adopted by the ISO, it seems. You will either see it as useful or you won't. I'm not trying to change your mind.

I'm not a fan of all li-ion batteries. The BankManager is only configured to run LiFePO4 batteries. Other li-ion cells are prone to thermal run away (especially when charged wrong). LiFePO4 is particularly safe (extra important on a boat) and lasts a lot longer. If you use a BankManager with a LiFePO4 in a car audio system you can charge all your batteries with your alternator while running the engine and assuming you are going to run a relatively small Li bank I added a feature to the menu that can temporarily disconnect the lithium bank while you start the engine. Li really isn't for that kind of load.

If you used my BankManager the starter lead would be held to 13.2 until the HOUSE Li went flat. Then it would be disconnected to preserve it for starting your engine so it's EXTREMELY unlikely your lead starter would go flat even if you left the lights on.

@@EmilyAndClark Hi and many thanks for the reply, it's appreciated....Being completely honest, by the time I factor in shipping, import duty etc the cost would be prohibitive but for other RV owners this might be an option....I help out on a few American based Facebook groups so this could be relevant and I'd be happy to spread the word.... My scenario then.....I have a split charge relay (voltage sensing ) to keep the starter battery charged when on solar or shore power and I understand that the battery manager would keep the starter battery charged....However, the question still remains in case of emergency as to how you would combine the the two battery sets when using the auxiliary start function that most if not all American manufactured RV's have...Just for info...I am UK based but my RV is American... Thanks again and look forward to hearing from you.

You could always make a jumper switch that bridges the batteries together if you think that would be useful.

And yes please spread the work on the BankManager please.

That's a serious misconception that slowly kills Li. Li just can't be charged "to a voltage" like lead. There is so much more to it. It can be fully charged at 13.7v or it can take power at 14.6 for quite some time depending on other factors. Charging beyond full slowly kills the cathode of your Li cells. Also repeated under charging causes a cell memory condition. If you set the BankManager for 100% it will charge the li fully but no more. For various reasons, but chiefly Li having a lower internal resistance, the li will take power faster and charge before your lead.

The BankManager runs at nominal 12v, 24v, 36v and 48v systems. My power supply section would fail above 80v so higher than 48v nominal is a total respin of the circuit.

I don't know what a BIRD relay is. The BankManager is a new thing. It's a battery bank management system. www.emilyandclarksadventure.com/bbms Here is some useful info on li and alternators kzfaq.info/get/bejne/oKmKmcRj15O1fY0.html

@@EmilyAndClark The BIRD (BI-DIRECTIONAL ISOLATOR RELAY DELAY) performs two important functions. It provides a method of charging the coach battery from the engine alternator and charges the chassis battery from the converter when the coach is plugged into shore power.

Yep almost the same thing. I bet the big difference is the price.

Hi Hank, Yep. You got it a little wrong. The batteries disconnect under charge so the lead voltage tends to go up after disconnect. Regardless there are much more complex instructions in the device that keeps it sorted. We have 500 happy customers, we must be doing something right. More detail here. kzfaq.info/get/bejne/jMCDpZmgmsyweHk.html

@@EmilyAndClark I see my mistake. 😁 The lead battery is not dropping voltage after charging stops.. After charging both batteries will keep the same voltage because they are connected.. So the bank manager does not disconnect. My bad!

I'll try to say it another way, It disconnects after the li finishes charging but reconnects once the Pb finishes charging

I'm obviously still figuring out how to explain it clearly. Thanks

@@EmilyAndClark This guy did an experiment without a bankmanager. What happens is that the lithium after a few minuted is trickle charging the lead battery. And both end up staying at around 13.4 volts. kzfaq.info/get/bejne/jquHeKidya2nmJc.htmlsi=TF6l6ASXTvcBZF6m Btw Thank you for you videos on the subject.. I feel confident to keep my Agm batteries and make them a very useful part of my 24 volt 4 battery 200 ah setup. Before seeing your videos I planned to sell them. 😊

Sorry we don't get a lot of 36v guys so I didn't do a special page for you. The bi-stable contactor is a 12v device. The resistors kinda eat up some power so the contactor only sees 12v of your 36v. Each resistor eats up (drops) about 12v. To wire them up go from the lead positive 3/8 contactor terminal through your fuse then through both resistors in series then to the contactor positive coil terminal (small and alone) Mount the resistors to a metal plate to help dissipate heat and protect your boat if things were to go wrong.

No problem. And with li being so much lighter and not needing the same ventilation conditions, it can be placed in more places.

@@EmilyAndClark thank you

It really doesn't take much. Especially if the lead battery in question is a thin plate starter type. I just put an FAQ section on the BankManager website. I talk about this a bit there. www.emilyandclarksadventure.com/bankmanager

@@EmilyAndClark thanks I will look at it.

Sure you can do it manually. I personally have both. So I can force the house into the starter even if the voltage is low. Just jump the vsr across the switch terminals

I think you want to look at our other videos. Take a look at our playlists

To the house lead. All charge sources and loads go to the house lead.

Well for a bi-stable contactor those are the same. If you fail while connected you stay connected. If you fail disconnected you stay disconnected. For a monostable NO any failure disconnects li bank For a monostable NC any failure connects the li bank If you are disconnected you can't use or charge your Li. If you are connected your Li is slightly overcharged by the lead charge controller as long as it basically stays below 14.6. If it tries to equalize your lead or your Li cells are not balanced your BMS steps in. During this time you are exposing your Li to low current overcharge. This is a slow certain death but you could go a year this way without destroying your Li. The bi-stable contactor has a cycle life large enough that it should outlive you in this application. The BankManager is made as robust as I could make it including having an independent watchdog timer to reboot it if it were to lock up from a software or memory error.

The solar controller just doesn't let it pass to the batteries. Technically the panel voltage goes up to the point that the light doesn't have the activation energy to overcome it. The energy just heats the panel like it heats anything that color.

@@EmilyAndClark Thanks

@@EmilyAndClark Great videos. In the above scenario, could you use a grid-tied inverter to use the PV input?

It would be harder than you think to get them balanced when running together. Probably use some kind of voltage sensor on the battery side to flip the mppt/inverter with a relay would be the least technical way to make it work.

I was thinking about car audio when I designed the BankManager. It has some special features that were just for you guys though they turned out to be useful in campers, houses and boats as well. As I understand it a lot of you guys with Li charge the li at home. With the BankManager and the two battery model I show in this video you can charge your Li as you drive with your alternator and the li will be disconnected when you start your engine because Li just isn't for starting loads. So you can run independent of an AC charger. You can expect your amps to see 13v except from when you actually crank your engine to when your alternator kicks in. So you might hear bass clipping for like 5 seconds on engine start. www.emilyandclarksadventure.com/bbms

As of now it requires a currier. Reship.com was recommended by an Australian and we have been passing that recommendation on. We sell a lot of these to Australia. Your country is just expensive to get things into. Of course you could vote that away. I really don't know how to solve that. I imagine if I had a local distributor there would still be the customs charges but shipping might be less. If someone in Australia wanted to buy at least 10 I'd offer a discount so they could resell. I have a guy doing that in the EU.

Not so easy actually. I suggest you read Conrad's paper at the end of this page. www.emilyandclarksadventure.com/bbms Modern Li charge controllers destroy lifepo4

As I say at the beginning of the video. All loads and charge sources go to the lead. You may want to watch the beginning again

I don't exactly understand what you are asking. Regarding the alternator kzfaq.info/get/bejne/oKmKmcRj15O1fY0.html Watch this it might help.

The best way to charge your lifepo4 from a smaller alternator is a dc dc charger. There a many manufacturers of them but I would in your case recommend the Renogy dcc50s. This is a combined dc dc and mppt. Unlike some dc dc chargers if the input voltage drops with this model then the output current also drops. This means it won't overload your alternator at low rpm. If you get the remote control for it. You can adjust the maximum output current. This means you could de-rate it to say 40A to protect your alternator. It can take upto 25v of solar as well if you have solar.

Have you seen a 65a alternator overheat? I find the small ones continuous duty. I personally think dc-dc chargers solve two problems but cause several more.

@EmilyAndClark what problems do you think they cause. Our previous 50A alternator died. Which may also have been because of the a2b charger from sterling. Not all dc dc chargers are the same or fitted correctly.

It's not like they don't work I just find how they work sub optimal. The design of my BankManager was effected by trying to avoid some dc-dc issues. They waste power (like 20% goes to heat) They are one directional power from starter to house but not the other way. They will kill your starter bank if left on Seems as if there are more but it's early here. Not had coffee yet

Lead has some serious advantages over Li. And without a BankManager charging incorrectly is basically impossible in a live system.

I made this video and the one after it just for you. kzfaq.info/get/bejne/oKmKmcRj15O1fY0.html

kzfaq.info/get/bejne/jpqPgtJ0pp64mo0.html

I assume you are asking.g because you want to take advantage of the BankManager and it's ability to protect your Li bank. If so as I say in the video use your starter battery as your lead house battery. You won't touch that battery with house loads until your Li is over 80% discharged.

@@EmilyAndClark So there's no way to connect a VSR to protect the starter battery from being discharged without some form of Pb house battery? I guess I'll have to add a tiny AGM battery into the circuit for the VSR to reference from.

You do understand that your expensive li batteries are being charged wrong, right? I'm going over to a cruising boat today to look at his 1 year old li that has been cooked by Victron gear. We will try to recover some life into the cells and then he's installing a BankManager. Hopefully not too much damage has already happened. I might get a video out of it. Yes you could use a VSR between li and lead. It would turn off if the li was depleted below 20 percent. But any charge going to the lead would also go to the li. Li shouldn't be charged to a voltage limit and it can't be floated. The vsr wont help that.

Like it says on the buy page . www.emilyandclarksadventure.com/bbms We only ship to US addresses. There is a company called reship.com that can provide you with a US address and handle the customs for you.

Battery is always good to have, if not nice to carry. So more good. As for the minimum. Well that seems very system dependent. It comes down to keeping your charge controllers sane. It's very system dependent. Here are rules of thumb. - enough such that a big load coming onto lead alone doesn't drop voltage too fast - healthy fresh batteries can be smaller - starter batteries (thin plate) are not only cheaper but are better in this application as long as you don't plan on cycling them. I've set up a system with 7ah of lead that worked well. I've seen an installation with 200ah of old lead that couldn't tame a huge solar grid through cheap Chinese charge controllers.

In short this could be a whole video but sadly my answer would still be I don't know. It's system and requirement dependent.

You can do anything you like. Are you asking will the BankManager operate as a charging device without lead. The Gen3 will have that capability, something I developed for a guy building wheelchairs.

really appreciate reply im sure time is important thanks cobber. Actually i was wondering is the bank necessary can i just put lithium in and use it like a lead.@@EmilyAndClark

You mean a little starting battery for a motorbike? Sure just do it. They don't cost all that much and work fine until they die. I have a 1700cc v-twin, I use a little battery. Light and starts so much better than the lead.

@@EmilyAndClark 1700!! Wow Suzuki boulevard? You tearaway I'm green with envy. Thanks again I'll give a small donation first chance as appreciation. Born to be free you live it

Roadstar Warrior

That's a lot of questions. How about starting your research here. www.emilyandclarksadventure.com/bbms This all works very well we have sold 600 of these. There are lots of happy customers.

@EmilyAndClark OK. I just read the manual. Got it. Essentially you have a lead acid and a lithium battery connected in parallel, with a simple switch, that isolates the lithium under various programmed parameters. Thats all. That means that the highest charging voltage the lithium battery will ever see is the highest set by the lead acid system controllers, which is sub-optimal for the lithium battery,. Moreover, the lead acid is actively cycling, reducing its life expectancy too. No thanks.

@stephenburnage7687 No you really don't understand this. That's fine you can do your power system anyway you want.. But you are missing out.

@EmilyAndClark You may understand control systems but it is obvious that you know nothing about marine electrics. You do not lock lithium in parallel with lead acid, (nor do you lock wet lead acid in parallel with AGM). Yes, it may 'work' and yes, it may be 'safe', but you are operating the batteries outside their design parameters, shortening their life expectancy and almost certainly invalidating any warranty. Yes, you may have sold 500 of these but how many recognized battery manufacturers or licensed ABYC technicians are recommending this device? The only approach they will endorse is either to have an all lithium or all lead acid system or a mixed system whereby the two systems are properly isolated from each other. No thanks. On my boat intend to do things properly.

@stephenburnage7687 wow. You are a really hateful guy. I guess we are done here. I'm my defense I do seem to have some understanding of this new tech. The ISO has asked me to write a white paper to start them on a hybrid battery standard. They think I'm on to something here. There is a link to the document in our FAQ section.

Better find another channel then

Cheap but doesn't charge li safely. So when your Li is dead in 3 years instead of 15 is it a money savings. I suggest you look into "low current overcharge". Conrad's article at the bottom of this page is a good start. www.emilyandclarksadventure.com/bbms

I don't see why either. Know someone at Victron? Though they might not like me much after I do a video I'm working on. A boat in the harbor bought LiFePO4 last year. It's been charged with Victron set for Li. The batteries are failing! We will open them up and see what we can do then put him on a BankManager.

Sorry. Maybe watch it again?