Lithium Battery Revolution Phase II

Measuring DoD on any battery by Voltage is a rough estimate at best, and problematic with high amp draw applications like windlass/inverters due to Peukert's Law.

A smart shunt removes a lot of the variables, and regardless of battery chemistry, would be a great addition to keeping that battery bank heathy and maxing service life.

Thew Victron IP65 1000A (skip the standard) versions are abouty $200 and easily installed.
 
Back to the original new battery chemistry, many great things going on but it will be another 5 years before these things sort out and enough manufacturing ramps up for us to see options at reasonable prices. But always good news.

What I would love to see today is a next generation BMS. The current generation being all about protecting the battery and the cells only.

For true "drop in" we need a BMS that goes beyond the battery, one that is intelligent enough to self limit charging. Maybe a small app that lets you select you alternator size and controls charging to say limit charging to 90% of your rated alternator for 15 minutes, then tapering down to 50%. Has built in surge suppression on battery disconnect, perhaps with a small dump load that eases the disconnect for a few seconds.
Another item would be some type of cranking control. Say a third terminal on the battery that simply connects to the starter solenoid so the BMS know your cranking and bypasses the current limits of the BMS for say 15-30 seconds.

These things can be added externally but that's where you get into having to redesign the boat. Wakespeed/Balmer regulators etc.

I think someone out there could capture the auto, truck, RV, marine market with a true "smart drop-in".
 
hughespat57 said:
Back to the original new battery chemistry, many great things going on but it will be another 5 years before these things sort out and enough manufacturing ramps up for us to see options at reasonable prices. But always good news.

What I would love to see today is a next generation BMS. The current generation being all about protecting the battery and the cells only.

For true "drop in" we need a BMS that goes beyond the battery, one that is intelligent enough to self limit charging. Maybe a small app that lets you select you alternator size and controls charging to say limit charging to 90% of your rated alternator for 15 minutes, then tapering down to 50%. Has built in surge suppression on battery disconnect, perhaps with a small dump load that eases the disconnect for a few seconds.
Another item would be some type of cranking control. Say a third terminal on the battery that simply connects to the starter solenoid so the BMS know your cranking and bypasses the current limits of the BMS for say 15-30 seconds.

These things can be added externally but that's where you get into having to redesign the boat. Wakespeed/Balmer regulators etc.

I think someone out there could capture the auto, truck, RV, marine market with a true "smart drop-in".
Click to expand...
Yes - spot on. Victron's BMS is getting there but mostly requires Victron equipment around it to be on their proprietary network.
 
dtfeld said:
I would think a combination thruster/inverter battery makes a lot of sense to go with a LiFePO4 battery, and sized appropriately, would be a really nice upgrade to your boat. I say sized appropriately because, if you do a rough audit of your daily 12/24V DC requirements, you might be just as well off with a set of 4 smaller batteries, set up in a 2S/2P. That would give you 200Ah @ 24V.
Click to expand...


I think so too... as long as the battery bank can meet the thruster's current requirements. 560A, in this case.

As it is, we've got 255-Ah (initial) capacity at 24V, and that's semi-decent. With some load management and alarm value experimentation last week, we were able to get through the night and still make morning coffee on battery/inverter.

And that might be enough, given cost and pain of additional improvement. I'm constrained by space, a bit. Easiest solution has been to use already-designated real estate (existing thruster bank) and there aren't many combos of smaller batteries that will fit the same space. 4x Lifeline 6CT (300-Ah) or especially L16s (400-Ah) would be much taller and I'm not sure how the horizontal footprint might work, 4x Odyssey AGM470FTTs (428-Ah) are 2" too long and much taller... etc.... and taller sorta blocks off a lot of access to the bilge.

I think lithium batteries that roughly fits those same "BCI Group" sizes come with the same obstruction issues. And while lithiums (even smaller ones) can be discharged more deeply, so far I haven't seemed to be able to find a configuration that will deal with thruster current. Maybe. Not sure I know what I'm talking about, there.

I know our current AGMs have decent CCA ratings, but I dunno how that might translate to peak and continuous current output. Might be some math to translate, but if so I don't know it.

-Chris
 
ranger58sb said:
Uh... no. Not fully discharged at 50% of rated capacity. Per manufacturer (Lifeline, in this case), longest lifespan is to not routinely discharge lower than 50%. Different thing. Fully discharged (100% DoD) 12V battery is 10.5V, whereas 50% DoD is 12.15V. Different chart, open circuit voltage at 0% SOC is <11.58V and OCV at 50% SOC is 12.18V.

Yep, understand all that about lithium capabilities... greatly increased depth without damage, etc.

And thanks for confirming math.

All I've got is thruster specs, which I assume would be "worst case" or some such? (Max draw?) How measure? Multi-meter during operation? At the thruster?

All (or at least most) of this relevant to my earlier comment about battery architecture. I perceive it as a boatload of work to split engine starting from house service, and from thruster service to house service. And real-estate for a whole 'nother battery bank, with manageable wire pulls, isn't all that easy to come up with.

So that influenced my earlier decision to just re-purpose (multi-purpose) our thruster bank to service the inverter too... and call it good. It took replacing the earlier charger with an inverter charger (plus remote control panel and monitor), some short wiring pulls and some additional connections inside the AC/DC panel, done. Not even all that expensive, in the grand scheme of things.

-Chris
Click to expand...
You are right recommended depth of discharge is 50% for SLA batteries and they are not yet fully discharged. Thanks for the correction. However, the life cycle of your expensive deep cycle batteries will greatly suffer if discharge is greater than that 50%.
The Lithium battery isn't impacted as great as a percentage of remaining life when discharged below the manufacturer's recommended DOD's.
Regardless the energy available for use is greater by a substantial margin in the lithium batteries.

Ok - as far as your bow thruster the maximum current draw must be for a locked rotor. In other words, that initial start current. That is a short term transient condition that, in reality, probably doesn't really happen. For example, I kept reading my engines needed 800 amps to crank them. After I measured the actual current it ends up being more like a 250ms current of 600 amps and actual cranking of 350 amps. That is why I'd measure actuals. Then downsize the circuit breaker to better be compatible with both the thruster and size a lithium battery bank.
 
ttmott said:
Regardless the energy available for use is greater by a substantial margin in the lithium batteries.

Ok - as far as your bow thruster the maximum current draw must be for a locked rotor. In other words, that initial start current. That is a short term transient condition that, in reality, probably doesn't really happen. For example, I kept reading my engines needed 800 amps to crank them. After I measured the actual current it ends up being more like a 250ms current of 600 amps and actual cranking of 350 amps. That is why I'd measure actuals. Then downsize the circuit breaker to better be compatible with both the thruster and size a lithium battery bank.
Click to expand...

First, yep... more energy available.

I'm in the "is it worth the pain" category. Doing nothing (more) is seeming semi-satisfactory. :)

Does it happen that CCA/MCA/HCA specs are measures of continuous (or maybe peak) current?

I just discovered (noticed) a footnote associate with our thruster spec:
Current: 560A
The footnote is: "4,5 min. continuously or max 4.5 min per hour at 560A (24 Volt)."
(The 4,5 with comma and 4.5 with period are as written... by a Dutch company).​

There's also a category named Rating, and the entry there is 4,5 min (with same above footnote).

Minimum and maximum battery ratings for the thruster are 950 and 1900 CCA respectively (so our existing 1350 CCA is well within that range).

That seems to suggest that CCA/MCA/HCA are NOT direct continuous (or maybe peak) current values... if a minimum CCA of 950 is assumed to be required to deliver 560A for 4.5 mins. But I'm way out of my depth on stuff like that...

-Chris
 
If youre out alot over night and just squeeking by in the morning fir coffee and breakfast, it definitely going to give you more headroom, especially as the LA batteries age.

also, the cost of ownership over time is starting to favor lithium.
 
hughespat57 said:
Back to the original new battery chemistry, many great things going on but it will be another 5 years before these things sort out and enough manufacturing ramps up for us to see options at reasonable prices. But always good news.

What I would love to see today is a next generation BMS. The current generation being all about protecting the battery and the cells only.

For true "drop in" we need a BMS that goes beyond the battery, one that is intelligent enough to self limit charging. Maybe a small app that lets you select you alternator size and controls charging to say limit charging to 90% of your rated alternator for 15 minutes, then tapering down to 50%. Has built in surge suppression on battery disconnect, perhaps with a small dump load that eases the disconnect for a few seconds.
Another item would be some type of cranking control. Say a third terminal on the battery that simply connects to the starter solenoid so the BMS know your cranking and bypasses the current limits of the BMS for say 15-30 seconds.

These things can be added externally but that's where you get into having to redesign the boat. Wakespeed/Balmer regulators etc.

I think someone out there could capture the auto, truck, RV, marine market with a true "smart drop-in".
Click to expand...
This battery addresses some of your concerns. But it’s pricey

https://panbo.com/lithium-pros-lifepo4-batteries-small-boat-battery-perfection/
 
jmauld said:
This battery addresses some of your concerns. But it’s pricey

https://panbo.com/lithium-pros-lifepo4-batteries-small-boat-battery-perfection/
Click to expand...
We had considered supplementing engine starting with Maxwell Supercapacitors (like these batteries do) which are specific for diesel engine starting. It solves the lithium shortfall but adds another $2500 in cost to the system.
The downside of these batteries is they cannot be paralleled or in series (well they allow two batteries in parallel).
 
ranger58sb said:
Almost begins to sound nifty for my application, too, but... yes it's pricey ($5400/pair compared to $1500)... and the ones they list as starting batteries are "NOTE: Not for use in series to make higher voltage packs. 12V systems only."

Drat. (Sort of.)

-Chris
Click to expand...
But it shows you how to address your bow thruster issue. I think you could do a 2s2p configuration like ttmott suggests. The in-rush current is very short lived and likely won’t be an issue. As long as you keep that thruster free of barnacles.
 
jmauld said:
But it shows you how to address your bow thruster issue. I think you could do a 2s2p configuration like ttmott suggests. The in-rush current is very short lived and likely won’t be an issue. As long as you keep that thruster free of barnacles.
Click to expand...


Apparently not with Lithium Pro batteries, per their website.

In the grand scheme of things, I'm not really having an "issue." More like just wondering if I could (or could have done) a useful improvement at reasonable cost and without much installation/reconfiguration pain.

And the Panbo link generally touches on the topic too: LiFePO4 house batteries are good, lithium not so good for start or thruster batteries. The exception he then goes toward is specifically for a 12V system. (He mentioned 24V and 36V batteries on the Lithium Pro website, but turns out those are only for trolling motors; none for starting. And their prohibition against serial-ing (?) their 12V starting batteries.)

So far, the answer to my "wondering" appears to be that I could improve somewhat, at great cost*, and by ignoring some of the Sea Ray schematics or Vetus documention (or making mods or accepting changes that don't meet some of their published specs).

I don't have enough of a clue to be comfortable with the idea of down-sizing circuit breakers or fuses or whatever, and doubt I'd be able to defend something like that in case of an electrical fire or whatever... even if completely unrelated to various changes.

(* The great cost thing is also impacted by our age clocks. We're old, Not sure how much longer we'll be able to boat. Having trouble with stairs already, etc. An expensive installation that needs 10+ years to amortize isn't necessarily all that attractive. Especially because I'm also already WAY overbudget fixing issues PO (or maybe multiple POs) apparently ignored.)

-Chris
 
The intent of this thread was to illustrate that the Lithium battery tech is about to undergo a major change which would definitely benefit boating (and everything using stored energy) in general.
Chris - assuredly you could use lithium batteries for both your thrusters as well as support inverter loads. It is all about how you understand the application and how you approach the project. If this is unfamiliar territory then for sure I'd either seek some help or continue with what is there already.
 
ranger58sb said:
Apparently not with Lithium Pro batteries, per their website.

In the grand scheme of things, I'm not really having an "issue." More like just wondering if I could (or could have done) a useful improvement at reasonable cost and without much installation/reconfiguration pain.

And the Panbo link generally touches on the topic too: LiFePO4 house batteries are good, lithium not so good for start or thruster batteries. The exception he then goes toward is specifically for a 12V system. (He mentioned 24V and 36V batteries on the Lithium Pro website, but turns out those are only for trolling motors; none for starting. And their prohibition against serial-ing (?) their 12V starting batteries.)

So far, the answer to my "wondering" appears to be that I could improve somewhat, at great cost*, and by ignoring some of the Sea Ray schematics or Vetus documention (or making mods or accepting changes that don't meet some of their published specs).

I don't have enough of a clue to be comfortable with the idea of down-sizing circuit breakers or fuses or whatever, and doubt I'd be able to defend something like that in case of an electrical fire or whatever... even if completely unrelated to various changes.

(* The great cost thing is also impacted by our age clocks. We're old, Not sure how much longer we'll be able to boat. Having trouble with stairs already, etc. An expensive installation that needs 10+ years to amortize isn't necessarily all that attractive. Especially because I'm also already WAY overbudget fixing issues PO (or maybe multiple POs) apparently ignored.)

-Chris
Click to expand...
I meant in general, not those specific batteries. Why don't you assemble your own using 280AH cells? I would be comfortable using those for you application. Assuming you just use the bow thruster for small corrections.
 
ttmott said:
The intent of this thread was to illustrate that the Lithium battery tech is about to undergo a major change which would definitely benefit boating (and everything using stored energy) in general.
Chris - assuredly you could use lithium batteries for both your thrusters as well as support inverter loads. It is all about how you understand the application and how you approach the project. If this is unfamiliar territory then for sure I'd either seek some help or continue with what is there already.
Click to expand...

Yep, lack of confidence, because unfamiliar territory. That pretty much captures it. :)

I do look forward to tech evolution, though!


jmauld said:
Why don't you assemble your own using 280AH cells? I would be comfortable using those for you application. Assuming you just use the bow thruster for small corrections.
Click to expand...

Doing my own assembly sounds like a recipe for... ummm... not so good. :)

So far, we've mostly only used the thruster after getting ourselves into a slip or up to a face dock... to get Admiral close enough to a forward pile to get a line on.

OTOH, I can imagine an occasional situation that might really work much better with a full-power thruster and a few minutes of leaning on it.

-Chris
 
4/0 wire is only capable of about 300-400A in a marine application, so I doubt your going to hit limits especially with a 24V system.

Get a set of these in the marine grade --> https://www.us.sokbattery.com/

Or use these guys for a DIY battery. For the record, I have 2 of their 304 Ah batteries w/200A BMS running my inverter --> https://www.sunfunkits.com/

Not the new technology Tom is referring to but its here today, works well, and at a reasonable cost.
 
dtfeld said:
4/0 wire is only capable of about 300-400A in a marine application, so I doubt your going to hit limits especially with a 24V system.
Click to expand...

Thanks, that could be useful. There's a 350A fuse, which is a) right in that range, and b) lots less than the 560a Vetus spec. Dunno wire size, but the parts manual says the harness is 60' long.

-Chris
 
Very odd spec...355A slow blow fuse with a 540A current consumption? Hmmm. They spec up to 85' of 4/0 wire, so again, your in the 350A range which 2x LiFePO4 batteries with a 200A BMS will easily handle.

If serious, a call to Vetrus would clear it up I think.
 
b_arrington said:
That's kind of where I was going with the charge rates. Electrical infrastructure in slips can be kinda dodgy. And lots of boats are on moorings without regular access to power between uses.
Click to expand...
Hey Brad - Every marina we have been to including the Bahamas and Florida Keys have 50A 240V power so, at least in my experience, hasn't been an issue. A 100 amp battery charger at 12 volts DC is only a 5 amp load on the 240V shorepower system; consequently a 10 amp load for a 120V shorepower service. The generator on my boat can obviously manage a large DC load to charge batteries.

Where I think things are going for big lithium battery bank charging on boats is a single small diesel DC generator dedicated to charging the battery bank and there will not be an AC generator. The boat's AC power systems will all be on inverters. Obviously, the boat's main engines will have robust alternators to supplement. This is going to bring boating to a new level of comfort and fuel efficiency. Generac for their residential battery backup systems now have a small DC generator specifically to recharge their PwrCell batteries when there isn't enough sunlight for the PV system to do that recharging.
With the possibility of battery energy density more than doubling again in this new technology, we are in the realm of moving away from AC generators in our boats.
 
^^^This

Companies are already staking out their claim to be the next Westerbeke of onboard/marine DC generation. Couple that to a new generation of battery tech, and I think the AC generator on a boat will be history.

——> https://polarpower.com/marine-dc-generators/
 
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