Li-ion Upgrade questions

[GrahamO]

Good morning,
I am upgrading my sailboat to Li Batteries, primarily to get more efficient charging and I have a number of configuration questions that I would very much appreciate help with.

My current system configuration is as follows:

Batteries:
4 x Lifeline GPL-4CT 220Ah 6v house batteries in series parallel providing 440Ah at 12v.
1 x 12v AGM starter battery.

Charging:
125A engine driven alternator with serpentine belt. Balmar Max Charge MC-612 regulator.
400w of solar panels with Morningstar MPPT40 controller.
Xantrex Digital Echo Charge charging the starter battery.

SOC monitoring:
Xantrex battery monitor

Here are my questions:
1. Both my solar charger (Morningstar MPPT40) and my alternator regulator (Balmar 612) are highly configurable so I am assuming that I will be able to set them up for Li batteries. Is this correct?

2. The Xantrex battery monitor for my AGMs is fairly configurable but presumably designed for lead acid battery discharge profiles. Can that be set up to correctly monitor Li batteries charge level? If not, what is the alternative?

3. I would like to keep the AGM starter battery but I assume that the echo charge is not going to work for different battery types. How else can I deal with this?

4. I currently have 440ah of AGM batteries. Typically they only drop to around 70-80%. In exceptional circumstances they have got down to 50%. I am assuming that with deeper discharge capability and much more efficient charging 300ah of Li batteries will suffice. Is that assessment reasonable?

5. I'm looking at Battle Born 100Ah batteries. Does anyone have any good or bad experience with them?

Thanks for your help!

Graham
www.sailingleela.com

[Dsanduril]

1. Both of those units are flexible enough that you should be able to configure them to work. Battleborn suggests 14.4 to 14.6V. Fair spread of opinions about how far you drop for float setting, but both units can do it. If you don’t already have it set on the 612 you’ll probably want to turn on the amp manager.

2. If it is the LinkPro there are settings for charge efficiency (set in high 90’s for Li) and Peukert (set to 1 to disable). With those two SoC should get close, and you can always just use the amp counter.

3. The Echo turns on at 13.0V, don’t think you can change that. So it will probably keep your start battery connected most of the time. Decisions...

4. Sounds about right, although I would probably go to 400Ah myself (if money was no object) in order to gain some potential “no charging” time. Money, however, is always an object.

5. No info.

[GrahamO]

Thanks D,
Great info but need to solve the starter battery charging issue. I would prefer 400Ah but that requires a completely new battery box and that is not a project I want to tackle at anchor in French Polynesia..... Can always add one later.

[two-rocks]

I have 300ah of battleborn. They are great so far - only a month - but that’s everyday cycling.

In my case I charge to full when the sun allows, and pay no attention to trying for a partial charge. Reason is that they start to drop as soon as the sun fades, so minimal time a full. Sitting plugged in at a dock is different.

Also- we run lots of things (inverter 24/7 fridge/freezer and another dometic freezer, etc)...and find 300ah is plenty. Although it’s currently cold here (diesel heater 24/7).

As for different battery chemistry starting-I have an agm and victron Orion smart dc-dc that works great.

Also FYI, just to nitpick ;-) is lithium iron in our case (LiFePO4)

[Flod]

I switched from 260 Ah lead acid to 200ah lifepo4. Gave me plenty of more power! It’s good to keep the start battery as a way of dumping the load when the lifepo4 gets full. If you go with battleborns I think they have a built in BMS that disconnect the chargers at certain parameters (high voltage, high temp etc) if you run your alternator and get a sudden disconnect of the batteries this will blow your alt. So keeping the start battery acts as an airbag for this

[GrahamO]

Originally Posted by Flod

I switched from 260 Ah lead acid to 200ah lifepo4. Gave me plenty of more power! It’s good to keep the start battery as a way of dumping the load when the lifepo4 gets full. If you go with battleborns I think they have a built in BMS that disconnect the chargers at certain parameters (high voltage, high temp etc) if you run your alternator and get a sudden disconnect of the batteries this will blow your alt. So keeping the start battery acts as an airbag for this

Thanks, I think the correct settings on the Balmar regulator should prevent sudden disconnects? How do you separately charge the starter battery from a common power source?

[GrahamO]

Thanks two rocks. Nit pick accepted. Thought I could edit the title but apparently not.... Victron looks ideal.

[Dsanduril]

Magnum, for one, makes an adjustable voltage battery combiner. I know there are others. The Magnum ME-SBC can be set to join between 12.8 and 13.8 and disconnect as high as 13.5, which I think would be enough.

Not a particular recommendation, I have not used it, and I do know there are others out there. With an external BMS this is actually simpler, but with the Battleborn built-in you don't have the flexibility. Still, should be able to get something for < $100 that would do the trick.

[Flod]

Originally Posted by GrahamO

Thanks, I think the correct settings on the Balmar regulator should prevent sudden disconnects? How do you separately charge the starter battery from a common power source?

I use a Sterling Alternator to Battery charger. Don’t think it can be combined with the Balmqr regulator but maybe you can find some other kind of charge split device.

[Flod]

GrahamO you should read this article:
https://marinehowto.com/lifepo4-batteries-on-boats/

I think it is very enlightening and a good starts to understand the setup you are trying to achieve

[GrahamO]

Thanks and Urk...
First reaction was "think I'll just get a couple more solar panels..... But, pressing on - it is a bit unfortunate that this article has not been rewritten to separate the very complex DIY from the more practical options as it has become a complex tangle, but there are some gem's in it such as the need to protect the alternator from sudden open circuit and the wide range of different 'what's in the box?' options. Still analysing. I may revert to the upgrade the solar option but it doesn't solve the tapering charge current problem. I will spec something up and present it for critique.

Graham

Originally Posted by Flod

GrahamO you should read this article:
https://marinehowto.com/lifepo4-batteries-on-boats/

I think it is very enlightening and a good starts to understand the setup you are trying to achieve

[Flod]

Don’t get frightened of the in depth analysis provided in the article. I went the DIY way and created a simple setup that works great for cruising. To me the essentials are:

1. You need a relay or some other device that can disconnect the batteries from charge/load sources at high/low voltage and high temp/low temp. Preferably on cell level. There are several suppliers of this and can be done in several ways. I used a 123Bms and a 123 Dual relay. All purpose built (https://123electric.eu) and easy to connect yourself. Gives me full control on cell level and easy management of the parameters via the included app. Also gives me a battery SOC meter which I didn’t have before.
2. You need all charge sources to charge the batteries to 100% soc and then stop. No float. I do this via a setting in the bms (as soon as all cells are over 3.40 or any cell is over 3.70 the bms trips the charge relay) or via a manual switch. I’ll watch the 123Bms app via Bluetooth and can manually decide to stop charging if I want. When on shore power I use my old lead/acid charger set to no float/boost mode. Just steady 13,,9 ish V. My solar and the alt (via the sterling lifepo4 setting) is also set to just provide a steady voltage. No miracle 3-step programs or anything. Just steady voltage around 14 V.
3. You need to protect the alt from burning up from to much load and from suddenly having no load. This has already been discussed and I use at lead/acid starter battery in combination with a sterling alt to batt charger. You should be able to use your balmar regulator and a combiner to achieve this.

If you can manage these 3 things without totally redesigning your current setup I think you should consider a DIY solution. It gives you more control than the drop ins and is equally easy to install.

[GrahamO]

Thanks to all for the helpful input. We went for the following setup in the end:

3off Lithionics 125a/h batteries
Victron DC/DC charger for starter battery
Victron 100/50 Blue Solar controller
Sterling Alternator Protection Device
Bluesea terminal fuses
Reprogrammed Balmar 612
Reprogrammed zantrex battery monitor
Increased solar from 400w to 600w

I could have kept the Morningstar controller but it had a comms hardware failure so could not be appropriately configured.

We will need a new shore charger at some point but there is no requirement for that yet so we will address that one when we convert the boat from 110v (never used) to 220v in Australia.

Anyway, we are thrilled with the result. Battery management went from an annoying preoccupation to a non-event. We are typically fully charged by 11am (French Polynesia) and have masses of headroom for water-making and fridge defrosting.

One of the most impactful changes we have made.

[YANDINA]

Originally Posted by Dsanduril

Magnum, for one, makes an adjustable voltage battery combiner. I know there are others. The Magnum ME-SBC can be set to join between 12.8 and 13.8 and disconnect as high as 13.5, which I think would be enough.

Not a particular recommendation, I have not used it, and I do know there are others out there. With an external BMS this is actually simpler, but with the Battleborn built-in you don't have the flexibility. Still, should be able to get something for < $100 that would do the trick.

Yandina now has Lithium compatible combiners for linking a lead-acid starting battery to LiFePO4 Lithium batteries for100 amp and a 200 amp rated alternators or charging sources. 500 amp available on request.

[GordMay]

Recycled Li-ion batteries are as good as new

Lithium-ion batteries with recycled cathodes can be as good or better than ones that use freshly mined material. Researchers [1] shredded old batteries and reclaimed a mixture of nickel, manganese and cobalt that is commonly used for the cathodes of electric car batteries. When tested with industry-standard methods, the recycled batteries could store as much energy as a conventional one, and could be charged and discharged more times before needing to be replaced.
The new study [1], by Yan Wang, and a team including researchers from the US Advanced Battery Consortium (USABC), and battery company A123 Systems, shows that batteries with recycled cathodes can be as good as, or even better than, those using new state-of-the-art materials.

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[1] “Recycled cathode materials enabled superior performance for lithium-ion batteries” ~ by Xiaotu Ma et al
➥ https://www.cell.com/joule/fulltext/...351(21)00433-5