Lithium or Solar?

[gypsyvagabond]

I currently have my Beneteau Cyclades on the hard in Montenegro and am looking to increase the power I can use. I have 2 x lead acid 130 ah, so 260 ah. This is not even close to keeping up with pumps, lights, music, auto pilot, so I've had the fridge off = warm beers = problemo.

Initially thinking flexi solar on the canopy but...

My question is predominantly regarding the charging of the new lithium ion batteries. It appears as if they will charge almost fully after an hour running the engine? I would do this going in and out of anchorage and scouting around anyway so no problems if this is actually the case. I can then run them down to 50% and do the same the next day? I know that the batterie monitoring system will have this all sorted but would I be incorrect in thinking that if I had 400 odd amps of lithium in there then I wouldn't need to worry about solar at all?

(anyone know where I could get this installed in or near Montenegro?)

Hvala.

[Wraith_Mac]

Hvala,
There are many here who are very passionate about installing a LifePo4 battery.
Some do however get very technical in their cautions which may confuse a prospective user.
I understand their caution but recognize the success that many are having in day to day use of this tech, including me on a small scale.
I favor the tech, and keeping it at its simplest level for you can fairly easily begin using Lithium without any fancy computer [BMS] systems.
A low cost low voltage cut off relay is however essential in my opinion.
Charging as for AGMs if you're shore charger won't accept a custom setting will not hurt them until you get a more suitable charger.
Disconnecting any battery temp sensing wire your Lead Acid oriented charger may have is essential.
Two really good links to read are below.
These are from respected and known sources, pictures are easier to follow.
Lithium Batteries
Batteries On Board | Tahina Expedition
Cheers,
Mac

[deckofficer]

Good post Wraith_Mac. I'm an early adopter of LiFePO4 cells and agree my fellow users are getting technical. Start off with your series bank balanced at cell level, stay away from the knees during charge and discharge and your home free IMHO.

To the OP, your also correct about charge acceptance of the LiFePO4 cells and because of that you can charge quickly if your alternator is up to it. Go to this link and read what Stu and Maine Sail wrote here http://www.cruisersforum.com/forums/...ng-111467.html

[Wraith_Mac]

Hvala,
Even with a lithium battery I would suggest you add solar panel/s with an MPPT controller when you can to the extent you can.
I doubt you will ever regret it.
There are two LARGE threads on LiFePo4 here, this one pertains to housebanks,
http://www.cruisersforum.com/forums/...65069-197.html
Inside that 197 pages is a lot of very good information but it takes some sorting through.
Cheers,
Mac

[Wraith_Mac]

Originally Posted by deckofficer

Good post Wraith_Mac. I'm an early adopter of LiFePO4 cells and agree my fellow users are getting technical. Start off with your series bank balanced at cell level, stay away from the knees during charge and discharge and your home free IMHO.

Thanks Bob,
I know you are, I have been following this site since about when it started and the LiFe threads, every post on both main ones, since they started.
I appreciate all of the input that you, T1_Terry, Bob Ebaugh, Maine, Stu on electrics, a host of others on radios, rules, seamanship etc have made.
I'm not new to the sea nor am I the shy and retiring type but I have learned and continue to learn from others experiences here, large and small.
I got tired of just reading and not contributing where I can and joined even though I'm waiting for my next cat.
I want to be prepared to re-fit it ASAP and keeping up to date via this forum is invaluable.
Thanks again for all the good reading you have provided me.
Cheers,
Mac

[foggysail]

Originally Posted by Wraith_Mac

Hvala,
Even with a lithium battery I would suggest you add solar panel/s with an MPPT controller when you can to the extent you can.

So far, almost no problems here with your recommendations if budget is not a concern. But why an MPPT controller? Yes, they will provide slightly more charge than a cheapo PWM. The rub is for the cost of the controller you can purchase another panel or two that greatly increases the available charge. Of course space is also needed for the panels

[deckofficer]

Mac,

My first year on CF I was a lurker, learning from other's experiences and not contributing. In fact I didn't come out of the closet about my background until a little over a year ago in post #24 on Rebel Heart's thread http://www.cruisersforum.com/forums/...n-76308-2.html I just thought on a cruising forum, my MM background wasn't applicable. Some things are scale-able up or down, others aren't like the feeling of being in a big storm on a small vessel vs a large container ship.

[foggysail]

Bob--

Not sure I would/could enjoy a big storm even in a big boat. God bless you

[Wraith_Mac]

Originally Posted by foggysail

So far, almost no problems here with your recommendations if budget is not a concern. But why an MPPT controller? Yes, they will provide slightly more charge than a cheapo PWM. The rub is for the cost of the controller you can purchase another panel or two that greatly increases the available charge. Of course space is also needed for the panels

Foggy,
Yes a PWM controller is better than none [not a cheapo though] but I don't agree that it's TOO expensive to go MPPT, especially if the space available for panels is limited and shading is unavoidable.
The amount of shading that occurs over panels, even domestic ones justifies the expense to me, and not every one can add more panels.
I'd go so far as to say make sure the panels are a minimum 24v nominal for a 12v system and 48v for a 24v house system, wired in parallel not series, let MPPT controller farm that for even better results.
The case for MPPT vs PWM is argued all over the web, so I'll leave that alone here.
If a monohull has room to fit only one or two powerful panels, as is problably the case here then the MPPT tech will pay for itself IMO and it's not really that expensive is it?
Cheers,
Mac

[SVNeko]

Wow, a lithium thread that I can understand. What are you guys doing wrong?

[roetter]

Just put in 360Ah Lithium on my Bavaria replacing 720Ah LA. Originally the boat had 440Ah LA. The alternator is a Mitsubishi 115A (see http://www.cruisersforum.com/forums/...ng-111467.html).

Yes - the alternator can recharge the batteries a LOT faster, specifically compared to the last 20% on LA batteries, which takes forever. The Lithium go to 99% full and then the amps taper right down. The problem can be the alternator getting hot and the regulator cutting back the output or shutting down the alternator for a while to cool down. You can see some graphs in the "Alternator Overheating" thread.

My engine room is really well insulated with no fan, just the air the engine sucks in. After blowing all the dust of the cooling fins with compressed air my alternator is doing fine. I was able to restore 210Ah in less than 4 hours a few weeks ago, and that was with dust on the regulator, but a panel removed to allow better cooling.

Solar is great though. On another boat I had 950W and "lived" of only that for months at a time.

Lithium plus solar = heaven.

[Maine Sail]

My cautions would be around the charging voltages the manufacturers spec. PLEASE be very, very careful with these voltages. There is no need, with say Winston cells, to push even close to the upper knee.

I would suggest staying well away below it voltage wise and they will be pretty fool proof once balanced.. We've already seen some cells ruined by pushing the voltage too high and this gets pricey. Using LA voltages on my Winston cells? No way I'm doing that......

[noelex 77]

Welcome to the forum.

Lithium batteries are great, but like any battery they don't make power they just store the power produced.

Litium will accept power from the alternator much better than lead acid, but the alternator still needs to produce all the power you will use if you are at anchor without solar. Stock alternators do not produce much power so upgrading to lithium without larger alternators will only produce a very modest gain.

If you are using more power than you are producing a large battery bank of any chemistry will still go flat.

As boring as it might sound you need to do an energy budget and determine what power you are using and what you need to add to produce that power.

Solar is the easier option, but flexible panels are less efficient unless very expensive so mounting panels on a canopy does not usually result in a very high power array. You will need to do sums to see if you can mount enough to keep up with your demand.

[kevins]

with all due respect. Adding up sums is more difficult than just adding another solar panel

[deckofficer]

Back to the OP and the lithium or solar question, go both. If you don't have enough real estate for a lot of solar, at least size solar to meet fridge and freezer needs. Gives you freedom to leave the boat for longer periods.