Drop in lithium batteries

[tanglewood]

Originally Posted by a64pilot

OK so maybe not a simple drop in, but why not a manufactured kit? You buy as many relays etc as necessary for your system and install.

Look at it this way, I could have rolled my own Watermaker, but didn’t want to go through all the trials and tribulations of doing so. So I essentially bought a kit from Cruise RO, it’s not a simple plug in, drop a hose in the water thing, but it came with decent install instructions with just about every piece part required, and there are many.
Done correctly, it’s not a simple install, but it would have been orders of magnitude more work if I researched and ordered every single part.
Why can’t someone supply an LFP kit, like Rich does with his Cruise RO or others do with fridge ice box conversions?

I could cob together a refrigeration system, I have the license, training and equipment, but why would I when I can buy a kit and install it?

Somebody is missing a business opportunity here, I believe.

Professionally engineered kit is available from a number of vendors. Victron offers all the bits from batteries, to BMS brains, emergency disconnects, relays to control dumber chargers and loads, and control signals to control smarter devices. Plus tech papers on how to control their chargers and inverters using the control signals provided from the BMS. This kit can be designed into a new build, or retrofit into and existing system. But both require some attention and design to get it right, and currently those skills are few and far between. The skill base is growing, but it's a lot more complicated than anything else in an boat's electrical system, in my opinion.


And similar kit is available from MasterVolt, Lithionics, and surely others. But it's costly, and that's what drives people to more manual systems, or home brewed control systems.

[a64pilot]

Link to kits?

Also I guess I’m not making myself clear, I am not saying I can design a drop in.
I’m saying it can be done. To me a whole lot of electronics is smoke and mirrors as it is for almost all of us.
If you told me 20 yrs ago that a Radar that has good definition and a range of over 30 miles could be built and if have less RF than a cell phone, I would have smiled and told you that there is such a Radar, but it’s about six Ft across, two or more Ft thick, has a 5 mile range and cost in the neighborhood of 5 million dollars or more.
Now it’s a Simrad 4G Radar.

[john61ct]

Originally Posted by a64pilot

My Sterling Pro charge Ultra says it has a Lithium mode, but I don’t know what they mean by that.

It likely means a voltage setting much higher than what I'd ever let touch my bank.

The whole industry just follows what the mfg's spec.

[john61ct]

Originally Posted by a64pilot

OK so maybe not a simple drop in, but why not a manufactured kit?

Exactly what the packaged systems are!

[john61ct]

Originally Posted by a64pilot

However a drop in, could include its own charger couldn’t it?

Yes a DCDC charger, gets you the proper charge profile from whatever upstream DC source.

Take your Victron packaged system, add a Sterling 120A BB charger, now you **can** just drop that in anywhere you like.

Can even call it portable if you're a big strong fella.

[a64pilot]

Another way to skin the cat is the drop in has a small lead acid battery, and connects the chargers to it, then disconnects. That way the chargers are not suddenly disconnected, the small battery could be a small sealed exit sign battery or other widely available cheap battery.

Link to packaged systems? I don’t even know where to get started looking.

Or is there a good book explaining system design and recommending parts?
I figure after 6 months of messing with one, and likely a whole box of not needed parts, I could probably get one functioning, just I had rather install a proven kit, or if that is insanely expensive, then put together from a list of parts, following a design.

I have one, that a member was kind enough to send me, but it seems at first glance to be more rudimentary than what I want

[tanglewood]

Originally Posted by a64pilot

Link to kits?

Also I guess I’m not making myself clear, I am not saying I can design a drop in.
I’m saying it can be done. To me a whole lot of electronics is smoke and mirrors as it is for almost all of us.
If you told me 20 yrs ago that a Radar that has good definition and a range of over 30 miles could be built and if have less RF than a cell phone, I would have smiled and told you that there is such a Radar, but it’s about six Ft across, two or more Ft thick, has a 5 mile range and cost in the neighborhood of 5 million dollars or more.
Now it’s a Simrad 4G Radar.

I understand the sentiment about technology evolution. But as someone who had designed, built, marketed, and sold technology products for 30 years, I think this one will evolve a bit differently. I think we will see a fundamentally different, and better approach to power system control emerge from the transition to LFP. In fact, it's already happening with all the professionally engineered LFP power systems. Rather than chargers being autonomous devices pumping out power based on it's isolated view of what's happening in the power system, the batteries will direct the chargers' behavior based on what's happening at the batteries. This enables the more careful battery management required by most every modern battery technology, and also solves the problem of legacy chargers that operate based on their own output rather than the net battery current. That's a fundamental hole in LA chargers today that almost no products address.


Because there is a bunch of change in the design approach for LFP, I think it will be slow to spread. You can brew your own system, but that's only going to appeal to a tiny, tiny part of the market. You can buy a basket of parts from any of a number of vendors, but you still need someone to design it all into a sensible system, and those people are few and far between.


I think retrofits will emerge slowly, mostly constrained by the skills to design them. I know boat builders are starting to design systems based on the available baskets of parts, and I think that will represent the fastest spread of the technology. But only so many new boats are built/sold each year.


Part of the delay is waiting for the other components in the power system to fully support LFP with real features, not just words. Things like two stage charging rather than 3 stage, and better defined and controlled criteria for ending the charge cycle. Today there are examples of products ranging from that that have good LFP support features, all the way to some that are completely oblivious. Products with good LFP feaures have control inputs to stop and start charging via canbus, modbus, or just a pair of wires. Others have to be controlled via external relays to kill the field current to an alternator, or shut off power to a charger. Some can be programmed with LFP-friendly charge voltages and and absorb/float settings, where others have to be tricked into behaving in an acceptable way.


And then there is cost. Systems built around the professionally designed baskets of parts yield cost that are order 4x top quality AGMs, comparing usable ah to usable ah. That's a big price to pay for the LFP advantage. LFP cells alone are only about 1.5x the cost of AGMs. That's pretty compelling, and is what drives a small pool of zealots to brew their own BMSs. For a real market to develop, I think the cost with a pre-engineered BMS needs to be 2x AGM costs or less. I expect it will happen eventually, but it isn't there yet.

[tanglewood]

Originally Posted by a64pilot

Link to packaged systems? I don’t even know where to get started looking.

Here's a place to start https://www.victronenergy.com/batter...tery-24v-180ah. That link is to their battery module. The documentation links on that page lead to the other components like the BMS, disconnects, etc.


Then google Lithionics and MasterVolt for other examples.


But even with these packaged systems, there is a lot of work involved in evaluating your existing system, figuring out how all the chargers are going to be controlled by the BMS, selecting appropriately sizes relays, configuring control features in various components, then building and testing the whole system, including making sure everything is programmed correctly.

[john61ct]

And yes they are crazy expensive.

[Dockhead]

Originally Posted by tanglewood

I understand the sentiment about technology evolution. But as someone who had designed, built, marketed, and sold technology products for 30 years, I think this one will evolve a bit differently. I think we will see a fundamentally different, and better approach to power system control emerge from the transition to LFP. In fact, it's already happening with all the professionally engineered LFP power systems. Rather than chargers being autonomous devices pumping out power based on it's isolated view of what's happening in the power system, the batteries will direct the chargers' behavior based on what's happening at the batteries. This enables the more careful battery management required by most every modern battery technology, and also solves the problem of legacy chargers that operate based on their own output rather than the net battery current. That's a fundamental hole in LA chargers today that almost no products address.


Because there is a bunch of change in the design approach for LFP, I think it will be slow to spread. You can brew your own system, but that's only going to appeal to a tiny, tiny part of the market. You can buy a basket of parts from any of a number of vendors, but you still need someone to design it all into a sensible system, and those people are few and far between.


I think retrofits will emerge slowly, mostly constrained by the skills to design them. I know boat builders are starting to design systems based on the available baskets of parts, and I think that will represent the fastest spread of the technology. But only so many new boats are built/sold each year.


Part of the delay is waiting for the other components in the power system to fully support LFP with real features, not just words. Things like two stage charging rather than 3 stage, and better defined and controlled criteria for ending the charge cycle. Today there are examples of products ranging from that that have good LFP support features, all the way to some that are completely oblivious. Products with good LFP feaures have control inputs to stop and start charging via canbus, modbus, or just a pair of wires. Others have to be controlled via external relays to kill the field current to an alternator, or shut off power to a charger. Some can be programmed with LFP-friendly charge voltages and and absorb/float settings, where others have to be tricked into behaving in an acceptable way.


And then there is cost. Systems built around the professionally designed baskets of parts yield cost that are order 4x top quality AGMs, comparing usable ah to usable ah. That's a big price to pay for the LFP advantage. LFP cells alone are only about 1.5x the cost of AGMs. That's pretty compelling, and is what drives a small pool of zealots to brew their own BMSs. For a real market to develop, I think the cost with a pre-engineered BMS needs to be 2x AGM costs or less. I expect it will happen eventually, but it isn't there yet.

Sure, but what about new boats designed from the ground up for lithium? I've seen them being built. I guess this is going to really take off, because if the electrical system is designed from the beginning for lithium, the cost difference compared to lead is far less than when you are trying to adapt a lead-based infrastructure to a different system.


I would expect this to be the spearhead of propagation of lithium power.


A64 is concentrated on turnkey solutions that can be dropped into a lead system, but there is no reason for this to be the main front for development.


When electric lighting was first introduced, you could buy kits to convert oil and gas lights in existing houses. But very quickly new houses were being built which were designed from the beginning for electric lighting.



I think the same thing with lithium. The market for lithium systems which can be simply dropped into a lead power system is going to be limited by the cost of implementing that kind of backward engineering.



And it's not necessarily such a big deal to reconfigure an existing lead power system, such that a drop-in solution is even all that attractive, depending on the boat. I've enjoyed studying lithium systems these past few weeks and it seems to me that it's not all that intimidating after all, perfectly within reach of moderately nerdy owners, and certainly feasible for a decent marine electrician.



And Tanglewood has mentioned one other factor which I think is an important insight -- not just the BATTERIES, but also the CONTROL SYSTEMS for lithium power, are simply better. So the investment in control systems needed to accommodate lithium power is not just flushed down the toilet -- it gets you much more control over your power system.


As to total cost -- I don't think we're looking at this right. Just comparing usable amp/hours doesn't even account for difference in cycle life. For anyone who is cycle life limited, I believe lithium is already cheaper than lead, even considering the cost of the average installation, at least in Europe that is true. And besides that, not everyone considering lithium power has cost as the first priority -- people building million euro boats, for example, will likely care a lot more about the functionality of the system, than the cost of the system plus or minus a few thousand euros.



I expect we're going to see a huge increase of the use of these systems, even if the cost does not go down. The key factor will be, in my opinion, the accumulation of experience and approaches to installation and system architecture. A few good marine electricians who are installing a few systems a week each in customer boats might set the market on fire. A critical mass of nerdy owners doing their own installations and blogging about it, can also have a big effect. A manufacturer offering a really bomb-proof kit with BMS, contactors, monitor, with excellent instructions and tech support, for a reasonable price, can also have a huge effect. Once these trends start to take hold, I expect that a big percentage of that set of cruisers who spend much time off grid and actually put a lot of power through their batteries, will go to lithium, and that is whether or not the price of the cells goes down. I don't think the price of the cells is any any way a limiting factor even now -- per kW/h stored and delivered, lithium cells are already cheaper than any lead batteries.

[tanglewood]

I agree that new builds are where LFP will emerge the most. I don't know the figures, but I expect new builds are a small portion of the boat population, so proagation of LFP via new builds will be slow, even if all are LFP which of course they won't be. In the power trawler segment where I am involved, I see LFP in new builds, but I doubt more than 5% of boats built.


As for costs, I totally agree that people will pay more for the better performance characteristics of LFP, primarily faster charge and subsequent shorter gen run times. In fact, in the trawler segment, I'd say that's the primary motivation driving people to pay the premium and take the risk of an early adopter for LFP. But there is a limit. It's been very interesting working with a few buyers, including myself, plus a builder, and seeing what people value in LFP, and what price they are willing to pay. For me personally, the cost of a packaged Victron (or other) system is just too high to justify the benefits. That's why I'm buying cells and building the control system with a PLC. It's a science project, but fun for me, and makes the economics work. But there will never be a mass market around that approach.


The life cycle cost comparison between LFP and LA is an interesting one. I agree with the math, but don't think it will figure prominently with human behavior. We have demonstrated very, very clearly that given the choice between an inexpensive product that will have a shorter life space, and a more expensive quality product that will last longer, 99% of the buyers will select the less expensive product. With people's buying decisions, the short term economics greatly outweigh the long term economics.


But it's all very interesting stuff, both technologically, and from a market emergence standpoint.

[Dockhead]

Originally Posted by tanglewood

.. . . That's why I'm buying cells and building the control system with a PLC. It's a science project, but fun for me, and makes the economics work. But there will never be a mass market around that approach.. ..

Well, cruising boats altogether are not "mass market" products.


But I think that sourcing cells separately from the control and other elements of the system are not just for DIY. Besides boat builders including these systems into new builds, a decent marine electrician ought to be able to get up to speed quickly and offer these installations to non-technical customers.



I wouldn't be surprised to see Victron or someone else, offering a BMS and other elements which will work together seamlessly with their charger/inverters, and which will allow the DIY'er or marine electrician to create an installation with minimum brain damage.


You are right about the prevalence of demand for cheap and short lived vs expensive and long lived -- typical short term consumer thinking -- but cruising boats aren't cheap and short term solutions in any case, and there are plenty of cruisers who can do the math on the economics of cycle life. Really, you just need someone like me who replaces lead batteries every 3 years and is getting sick of it, and that person will be willing to pay something to convert his boat and solve that problem, and then as a bonus get all the other benefits. It's quite a decent business case, I would say.

[Maine Sail]

Originally Posted by john61ct

Take your Victron packaged system, add a Sterling 120A BB charger, now you **can** just drop that in anywhere you like.

John,


Do you have a model # for this Sterling 120A B2B charger? We are Sterling dealers and this is not a product they offer. Lots of talk but you never want to count on when..

Charles has been promising a 100A+ ProCharge Ultra now for years & years but as of yet nothing. He's also been bugged numerous times update the software in the PCU's to allow custom absorption duration...

If you have a small bank, sub 200Ah, then a BB1260 could work for this but remember 60A is on the input side not an actual output rating.

If you are aware of the elusive BB12V 120A please let us know....

[john61ct]

https://www.sterling-power-usa.com/b...r12vto12v.aspx

Do not know if actually stocked.

And yes, nearly a year since Charles told me 180A coming RSN, also heard 240A on the horizon.

Prolly more demand for the alt-driven than mains at such high levels.

But stacking works too, just not as elegant.

[john61ct]

And I notice BBW vs BB series, does that mean any less user-customizable charging profile?