Jump to content

Lithium hybrid set up help required


luggsy

Featured Posts

Hi currently I am in Boston, I have 4 x 6 v Trojans that are at there end of life , I have a 200amp lithium & 2  x 12v 135 amp lead acid batteries , I need some one to fit them for me , been in touch with 2 marine electrical fitters one does not know enough about the hybrid set up the other one does tells me to ring him and don't get a answer getting a bit pixxed of now is there anyone on here who can set it all up for me obviously I will pay 

Edited by luggsy
Spelling
Link to comment
Share on other sites

I think you might find it difficult to get an installer to do it professionally for you. There is no consensus on how exactly to design and install a hybrid system as the ultimate user's mind, understanding and intentions about how to use it form an integral part of the installation. There is no such thing yet (AFAIK) as an idiot-proof hybrid installation, or probably ANY lithium installation really. People are quite possibly not ringing you back because there is so much scope for it to all go horribly wrong and find you blaming them for a 'faulty' installation.

 

HST, Nick often recommends Ed from Four Counties. Have you tried Ed? 

 

 

Link to comment
Share on other sites

This is I think one of the definitive videos on the subject. However, as implied above, it is something of a black art with not that much information out there for either the auto or marine worlds.

 

However, I expect IanD will be along to explain in very rationale terms why this is probably not the right way to go although it is something that the IWA Sustainable Boating Group will continue to explore and hopefully, in the fullness of time, come with some definitive answers.

 

This guy also has a video on the reverse scenario – adding lead acid to a lithium battery bank and the rationale for same.

 

 

Link to comment
Share on other sites

9 minutes ago, Up-Side-Down said:

This is I think one of the definitive videos on the subject. However, as implied above, it is something of a black art with not that much information out there for either the auto or marine worlds.

 

Thanks for the video. Anyone expecting to get straight into a concise description of how to install a lithium battery in parallel with their LAs is gonna be disappointed. It is mainly an explanation the basic theories of lead acid and lithium and the differences. He has some ideas about batts that don't really align with received wisdom about batts on here either! 

 

More specifically he expects you to have a user-adjustable charge voltage regulator, which most narrow boaters don't have. So I'm not sure this video is worth watching for boaters with conventional lead acid installations, hoping to add lithiums in parallel, simply and easily. 

Link to comment
Share on other sites

7 minutes ago, MtB said:

 

Thanks for the video. Anyone expecting to get straight into a concise description of how to install a lithium battery in parallel with their LAs is gonna be disappointed. It is mainly an explanation the basic theories of lead acid and lithium and the differences. He has some ideas about batts that don't really align with received wisdom about batts on here either! 

 

More specifically he expects you to have a user-adjustable charge voltage regulator, which most narrow boaters don't have. So I'm not sure this video is worth watching for boaters with conventional lead acid installations, hoping to add lithiums in parallel, simply and easily. 

It was a good description for absolute beginners of the merits and otherwise of lead and lithium and how they play together, but beyond that, not useful. For example, no mention of the alternator overheat thing. The guy seemed to charge his boat only by solar, which is of course pretty easily configurable, unlike an alternator.

Edited by nicknorman
Link to comment
Share on other sites

20 hours ago, luggsy said:

Hi currently I am in Boston, I have 4 x 6 v Trojans that are at there end of life , I have a 200amp lithium & 2  x 12v 135 amp lead acid batteries , I need some one to fit them for me , been in touch with 2 marine electrical fitters one does not know enough about the hybrid set up the other one does tells me to ring him and don't get a answer getting a bit pixxed of now is there anyone on here who can set it all up for me obviously I will pay 

I've installed a Hybrid Lithium system. It involved adding a high current Schotky diode and a bistable contactor into  the charge wiring, changing the alternator regulator to one which could be computer controlled, a PCB full of electronics and an Arduino running 2500 lines of code I wrote. The resulting system is stable and foolproof and I'd be happy for it to be used on my boat by other people. I would not sell copies of it: that would require extensive testing with different charge sources and different batteries.

 

Without casting aspersions, if you can find a marine electrical fitter capable of replicating what I did, I'd be very surprised. The skill-sets are rather different. 

 

MP

  • Greenie 1
Link to comment
Share on other sites

1 minute ago, nicknorman said:

It was a good description for absolute beginners of the merits and otherwise of lead and lithium and how they play together, but beyond that, not useful. For example, no mention of the alternator overheat thing. The guy seemed to charge his boat only by solar, which is of course pretty configurable.

 

Yes agreed and considering the OP, it is perhaps a good explanation of why the OP is finding it hard to get a boat electrician willing to just turn up and fit the batteries he has bought.  

Link to comment
Share on other sites

10 minutes ago, MoominPapa said:

I've installed a Hybrid Lithium system. It involved adding a high current Schotky diode and a bistable contactor into  the charge wiring, changing the alternator regulator to one which could be computer controlled, a PCB full of electronics and an Arduino running 2500 lines of code I wrote. The resulting system is stable and foolproof and I'd be happy for it to be used on my boat by other people. I would not sell copies of it: that would require extensive testing with different charge sources and different batteries.

 

Without casting aspersions, if you can find a marine electrical fitter capable of replicating what I did, I'd be very surprised. The skill-sets are rather different. 

 

MP

Well to be fair one can get Ed Shiers to install lithium with a commercial BMS that talks to a smart alternator regulator such as the Mastervolt Alpha or Wakespeed, and to Victron chargers /Combis, which would do the job nicely. But at quite some cost, I suspect. 
https://fourcountiesmarineservices.com/lithium-batteries/

Link to comment
Share on other sites

46 minutes ago, MoominPapa said:

 

 

Without casting aspersions, if you can find a marine electrical fitter capable of replicating what I did, I'd be very surprised. The skill-sets are rather different. 

 

 

 

thank you for using a meaningful description of the work performed by the bloke wot visits the boat and installs bits and bobs, albeit probably in a highly competent manner.

 

many folk use the word "engineer" to describe any bloke with an adjustable spanner or a pair of pliers in his pocket, from which so much confusion arises.  

  • Greenie 4
Link to comment
Share on other sites

4 minutes ago, Murflynn said:

 

thank you for using a meaningful description of the work performed by the bloke wot visits the boat and installs bits and bobs, albeit probably in a highly competent manner.

 

many folk use the word "engineer" to describe any bloke with an adjustable spanner or a pair of pliers in his pocket, from which so much confusion arises.  

The confusion probably arises from “Is there an engineer?” with the answer “Yes, it’s under them boards”.

  • Greenie 1
  • Haha 1
Link to comment
Share on other sites

12 minutes ago, Murflynn said:

 

thank you for using a meaningful description of the work performed by the bloke wot visits the boat and installs bits and bobs, albeit probably in a highly competent manner.

 

many folk use the word "engineer" to describe any bloke with an adjustable spanner or a pair of pliers in his pocket, from which so much confusion arises.  

I used the same term the OP did, so any credit is due to them.

 

MP.

 

Link to comment
Share on other sites

I once had a launch powered by a perfectly adequate Yanmar GM10 single cylinder watercooled. 

I sold the boat after 3 years and I vowed to never have an IC engine on another boat and have been relaxing to the purring of an electric outboard ever since.  

My latest is a lithium powered unit - totally standalone from my 12v bank.   Lovely!!

Link to comment
Share on other sites

The design, development and testing of Software, (particularly safety or business critical software)  is most definitely a job for an Engineer. 

 

Actualiy writing it is something else, but also requires skills.

 

N

 

 

  • Greenie 1
Link to comment
Share on other sites

2 hours ago, Murflynn said:

 

..... or keyboard warrior.

 

Rather than a keyboard worrier...?

 

I always think "keyboard warrior" should be spelled my way, as it is more akin to sheep worrying than actual warring.

 

 

Edited by MtB
Edit to remove spurious double quote
  • Haha 1
Link to comment
Share on other sites

4 hours ago, BEngo said:

The design, development and testing of Software, (particularly safety or business critical software)  is most definitely a job for an Engineer. 

 

Actualiy writing it is something else, but also requires skills.

 

N

 

 

 

With apologies for splitting hairs, but development of software is the actual writing of it. There is also a pretty good chance that a good chunk of the testing will come under the heading of 'development'.

Link to comment
Share on other sites

40 minutes ago, Col_T said:

 

With apologies for splitting hairs, but development of software is the actual writing of it. There is also a pretty good chance that a good chunk of the testing will come under the heading of 'development'.

I think Nick's point was perhaps that for a big project, there would be a Systems Analyst (do people still use that term?) who would design and control the big picture, whereas the actual people writing the code would just be creating a small module that carried out some function defined by the SA. So really, the designer was the SA, the coder was just bolting together some lines of code which didn't require much imagination. Of course for many smaller projects, the SA is the coder.

Edited by nicknorman
Link to comment
Share on other sites

On 04/02/2022 at 10:16, nicknorman said:

Well to be fair one can get Ed Shiers to install lithium with a commercial BMS that talks to a smart alternator regulator such as the Mastervolt Alpha or Wakespeed, and to Victron chargers /Combis, which would do the job nicely. But at quite some cost, I suspect. 
https://fourcountiesmarineservices.com/lithium-batteries/

 

But at least this way the OP would get a system designed and built by somebody who definitely *does* have the expertise to do it properly 🙂

 

(and will presumably be responsible for fixing it if anything goes wrong)

 

Don't know if he'll support a hybrid system though, he'll probably point out that if you're going to the cost and bother of installing lithiums there's not much point trying to force a square peg into a round hole by combining them with lead-acid -- this adds a lot to the difficulty of managing everything because you have to deal with the peculiarities of both battery types, which behave very differently. Pure lead-acid or pure lithium are much simpler to manage...

 

People usually want a hybrid battery system to try and save money, but IMHO there's no such thing as a cheap lead-acid/lithium battery system that delivers big benefits and is safe/reliable, unless you can do a proper DIY install like MoominPapa -- not a quick'n'dirty bodge job... 😞

Edited by IanD
Link to comment
Share on other sites

5 minutes ago, IanD said:

 

But at least this way the OP would get a system designed and built by somebody who definitely *does* have the expertise to do it properly 🙂

 

(and will presumably be responsible for fixing it if anything goes wrong)

 

Don't know if he'll support a hybrid system though, he'll probably point out that if you're going to the cost and bother of installing lithiums there's not much point trying to force a square peg into a round hole by combining them with lead-acid -- this adds a lot to the difficulty of managing everything because you have to deal with the peculiarities of both battery types, which behave very differently. Pure lead-acid or pure lithium are actually simpler...

I've gone for pure lithium as you know, and chucked out 450Ah of reasonably healthy Trojans in the process. But I can see that if on limited budget one could want to have a hybrid system ...  the Li will do all the work until it is in a low SoC, and then the LA will take over.

The problem arises with the charging. Even though both types could at a pinch be charged at the same voltage eg 14.4v, the problem comes in that the LA needs to be held at 14.4v for several hours whereas the Li wants to be held at 14.4v for about 15 minutes. So it is OK to follow the Li charge profile provided the LA hasn't been discharged. But if it has, the Li won't like the profile needed to fully charge the LA. And if you are not going to discharge the LA, there isn't much point in having it!

Link to comment
Share on other sites

8 minutes ago, nicknorman said:

I've gone for pure lithium as you know, and chucked out 450Ah of reasonably healthy Trojans in the process. But I can see that if on limited budget one could want to have a hybrid system ...  the Li will do all the work until it is in a low SoC, and then the LA will take over.

The problem arises with the charging. Even though both types could at a pinch be charged at the same voltage eg 14.4v, the problem comes in that the LA needs to be held at 14.4v for several hours whereas the Li wants to be held at 14.4v for about 15 minutes. So it is OK to follow the Li charge profile provided the LA hasn't been discharged. But if it has, the Li won't like the profile needed to fully charge the LA. And if you are not going to discharge the LA, there isn't much point in having it!

 

As you say, the problem with paralleled LA/Li is both charging and discharging. Li have a much flatter voltage vs. SoC curve, so as long as the voltage is within this range the Li do all the work, the LA do almost nothing.

 

But to fully charge the LA you have to go to or above 100% SoC for the Li for some time, and to use the LA capacity you have to go down to or below 0% SoC for the Li -- if you don't do this, there's no point having the LA at all. Which means disconnecting the Li at both ends of the voltage range -- relying on an internal BMS do disconnect at 0%/100% SoC is likely to lead to short Li battery life, these BMS limits are really there to deal with emergencies, not to be exercised regularly because cycling Li between 0% and 100% SoC on a regularly basis is not good for them.

 

Not to mention that Li can kill alternators (overheating) and vice versa (overvoltage) unless you have a properly-designed alternator and external controller for the purpose, which costs hundreds of pounds -- more than a grand if you have to get a new alternator too, as the Four Counties site explains...

Edited by IanD
Link to comment
Share on other sites

22 minutes ago, IanD said:

 

But to fully charge the LA you have to go to or above 100% SoC for the Li for some time, and to use the LA capacity you have to go down to or below 0% SoC for the Li -- if you don't do this, there's no point having the LA at all. Which means disconnecting the Li at both ends of the voltage range -- relying on an internal BMS do disconnect at 0%/100% SoC is likely to lead to short Li battery life, these BMS limits are really there to deal with emergencies, not to be exercised regularly because cycling Li between 0% and 100% SoC on a regularly basis is not good for them.

 

I dont think that's quite right, Li gets to 0% at 10v, at 12.7v or so when the LA would kick in,  it still has about 15%SoC and at 12v, the lowest you would want to take LA, it has about 10%. A BMS would not disconnect until around 10v or certainly less than 12v. But yes keeping a Li battery at 10% SoC isn't a great idea.

 

But I'm sure we can agree that LA is so last century. Or the century before. Time to move to 21st century!

Edited by nicknorman
Link to comment
Share on other sites

12 minutes ago, MtB said:

You're both overlooking the point of keeping a LA in parallel, which is nice simple way to save the alternator in the event of a high voltage automatic disconnect. 

 

I'm not ignoring that; the problem is that if you manage charge/discharge to suit the Li the LA will die before its time, and vice versa. If you have big LA+ small (cheaper) Li then you won't be using the capacity of the LA effectively, if you have small LA and big Li then why bother with the LA at all? A system where HV Li disconnects happen regularly (or ever...) is a badly designed one, because charging sources like alternators/MPPT/charger need to be properly controlled with Li.

 

If you want to protect the alternator from an HV disconnect with Li, voltage clamping devices are cheaply and easily available and don't have the problems of adding LA to Li.

 

https://sterling-power.com/products/alternator-open-circuit-protection-device

 

Cheap (upfront cost) big heavy simple easy (but care still needed) : traditional LA + alternator + MPPT

Expensive (upfront cost) small light long life (cheaper over lifetime than LA?) but needs proper charging control for all sources : Lithium

Hybrid : neither fish nor fowl -- not cheap, not simple, not easy, worst of both worlds?

 

Edited by IanD
Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.