Jump to content
Strawberry Orange Banana Lime Leaf Slate Sky Blueberry Grape Watermelon Chocolate Marble
Strawberry Orange Banana Lime Leaf Slate Sky Blueberry Grape Watermelon Chocolate Marble

Featured Posts

1 hour ago, Mike the Boilerman said:

 

Yes I thought that too but I forgave the chap because he is American and they can't help it. 

The quality of the stuff in his pages makes it worth cuting him some slack. 

Perhaps you might condense it into two pages for us Nick? That would be most helpful!

I think even without reading the article the condensed version would probably just say " Dont even think about it!! " no way Jose.

Share this post


Link to post
Share on other sites
16 minutes ago, mrsmelly said:

I think even without reading the article the condensed version would probably just say " Dont even think about it!! " no way Jose.

The guy talks about different types of systems ie

- a fully integrated and designed system (integrated with the charging and demand circuits) and

- drop in replacement for LAs

He clearly says dont do the later. Some companies selling BMS systems independently have stopped selling for DIY.

What I didnt see is how much exposure to high or low volatage results in dead batteries? Charging at 0°C pales into insignificance! He reports overvoltage and under voltage are amongst the main sources of wrecking batteries but he doesnt say if one event is sufficient to do it. He talks about voltage 'run-away' above and below the 'knees' in the voltage charge/discharge curve so it sounds like just one event of overcharging could wreck them and write off thousands of pounds of kit. Not forgetting this could be for individual cells, not just the overall bank so absolutely essential to ensure the bank is balanced. You cant just look at the overall voltage. He does say that when properly balanced, his system has lasted 700 cycles and is still in balance.

For me now, this is more about listening to others experience for the next 12/24 months to see if under/overvoltage and balancing can be controlled to the point where the bank cannot be wrecked.

It sounds like it may be possible to DIY a drop in replacement and add a BMS system, not letting the SoC drop below 20%, Charging at <14.0V to avoid high voltage and balancing the bank to start with and then maybe checking the balance (off the boat) every 12 months but:

- what if the voltage of the charge device goes over 14V?

-what if the the relays protecting the over voltage fail and allow the 14V+?

- What if the cells get out of balance and the auto balancing fails (the guy was adamant that auto balancing may not work)?

- What if the BMS circuitry fails and you dont know?

- What happens if you take a lightening strike? (.....a little one!)

A few too many 'what ifs' at the moment. A couple of years 'in field' experience should help.

Share this post


Link to post
Share on other sites
1 hour ago, rusty69 said:

He also mentions that the smartgauge is unlikely to work on lithium batteries...

That is correct. So, ignoring the fact that boaters are a minuscule part of their market anyway, they have other products specifically designed for lithium installations. 

Share this post


Link to post
Share on other sites
12 minutes ago, Dr Bob said:

He does say that when properly balanced, his system has lasted 700 cycles and is still in balance.

 

And importantly are still delivering full capacity or thereabouts. How many users could say the same about lead acid after 700 cycles?

 

14 minutes ago, Dr Bob said:

It sounds like it may be possible to DIY a drop in replacement and add a BMS system, not letting the SoC drop below 20%, Charging at <14.0V to avoid high voltage and balancing the bank to start with and then maybe checking the balance (off the boat) every 12 months

This is basically what I'm planing to do later on this year - probably October time so they're installed in time for winter (If I have enough money!)

 

17 minutes ago, Dr Bob said:

- what if the voltage of the charge device goes over 14V?

-what if the the relays protecting the over voltage fail and allow the 14V+?

As he explains in the link, the high voltage and low voltage cut should be a last resort. If it gets to that stage you've already had a failure of the charging system - the chance of 2 simultaneous failures should be quite slim in a well designed system. 

 

22 minutes ago, Dr Bob said:

- What if the cells get out of balance and the auto balancing fails (the guy was adamant that auto balancing may not work)?

There's a lot of heated discussion on this in the long thread that smileypete posted a link to earlier, including the risk of it failing short circuit and wrecking the cells. 

 

25 minutes ago, Dr Bob said:

A few too many 'what ifs' at the moment. A couple of years 'in field' experience should help.

There's quite a lot of experience of people using these successfully in the states for several years, and finally appears to be more consensus on safe operating voltages. The manufactures have revised the safe charging voltages down since first released following real world experience, but all appear more in agreement now. 

 

Tom

17 minutes ago, WotEver said:

That is correct. So, ignoring the fact that boaters are a minuscule part of their market anyway, they have other products specifically designed for lithium installations. 

Although probably not at prices affordable to boaters.....

Most users seem to report good accuracy with AH counting SOC gauges on these batteries. 

  • Greenie 1

Share this post


Link to post
Share on other sites
38 minutes ago, Dr Bob said:

A few too many 'what ifs' at the moment. A couple of years 'in field' experience should help.

I wonder how many failure stories will be published though, Not sure I would If I'd managed to wreck £1000's worth of equipment.

Share this post


Link to post
Share on other sites

I may be misunderstanding, but, I thought ONE of the benefits was that you could use 'all of the capacity' and needed a smaller battery bank than for FLA's.

I now read that they shouldn't be discharged below 20% SoC, and the recommendation is to only charge to about 80%-85% SoC, meaning you have use of approximately 60% of capacity, - not far away from the recommended 50% rule for FLA's.

So, am I correct in suggesting that is you have 5x 110ah FLA's you need the same(ish) in Lithiums ?, or, does the fact you only need run the engine for a couple of hours per day instead of 4 hours per day mean you can get away with a smaller bank ?

Confused.

 

Share this post


Link to post
Share on other sites
4 minutes ago, Alan de Enfield said:

I may be misunderstanding, but, I thought ONE of the benefits was that you could use 'all of the capacity' and needed a smaller battery bank than for FLA's.

I now read that they shouldn't be discharged below 20% SoC, and the recommendation is to only charge to about 80%-85% SoC, meaning you have use of approximately 60% of capacity, - not far away from the recommended 50% rule for FLA's.

So, am I correct in suggesting that is you have 5x 110ah FLA's you need the same(ish) in Lithiums ?, or, does the fact you only need run the engine for a couple of hours per day instead of 4 hours per day mean you can get away with a smaller bank ?

Confused.

 

In car terms most get charged to 100% and discharged to about 15%, but for us boaters its not needed as they charge so easy in comparison to a FLA [I have some on charge now even as we speak]

The advantage of charging fast from solar is that it will massively reduce running engines which is a good thing on so many levels. The real advantage of restricting the upper level to 85% and discharge to 20% is that they will a last longer and reduce the need to balance them 5000 cycles is achievable from quality batteries like the ones I purchased.

I have bought mine because I am building the all electric bathtub, but I would fit them to my current boat in a heartbeat rather than waste my money on FLAs [even though my tractions are now 13 years old] its a weight, size, no need to fill the watering system thing. I would move them into the boat though as sub zero temps are a charging problem.

Share this post


Link to post
Share on other sites
8 minutes ago, peterboat said:

or, does the fact you only need run the engine for a couple of hours per day instead of 4 hours per day mean you can get away with a smaller bank ?

 

Another fallacy. 

You cant charge them from your engine as fast as they can accept a charge, because your alternator will fry itself. 

Share this post


Link to post
Share on other sites
6 minutes ago, Mike the Boilerman said:

 

Another fallacy. 

You cant charge them from your engine as fast as they can accept a charge, because your alternator will fry itself. 

Quote what I put Mike solar will have done the bulk of charging in the summer before you start your engine [or it will in my case] Also you are going to restrict the voltage from the alternator to 13.6 volts

Share this post


Link to post
Share on other sites
3 minutes ago, peterboat said:

Also you are going to restrict the voltage from the alternator to 13.6 volts

Which is the voltage at which most alternators are rated at, so Mike’s point is valid. At 13.6V a 100A alternator will generate 100A (assuming it’s spinning fast enough) and will soon melt itself if it continues for any length of time. 

Share this post


Link to post
Share on other sites
12 minutes ago, Mike the Boilerman said:

 

Another fallacy. 

You cant charge them from your engine as fast as they can accept a charge, because your alternator will fry itself. 

I'm not sure this is true is it? My alternators have been quite happy supplying a 1200w vacuum cleaner and 450w sander continuously for a couple of hours via inverter - say 150a allowing for inverter loses. This was with current into/out of batteries hovering around 0a with engine running about 1500rpm, and no sign of alternators overheating. 

Not sure what the difference is between that usage or charging lithium batteries? 

  • Greenie 1

Share this post


Link to post
Share on other sites
3 hours ago, Tom and Bex said:

There's quite a lot of experience of people using these successfully in the states for several years, and finally appears to be more consensus on safe operating voltages. The manufactures have revised the safe charging voltages down since first released following real world experience, but all appear more in agreement now.

Tom

 

Tom, I agree. There are a lot of answers to the 'what ifs'. This thread has been very helpful in taking us forward and I think I am a lot nearer to fitting Lithiums. I am a lot clearer on charging and where the problems could lie but as I said earlier I will wait a bit until some more experience emerges. I am usually on the bleeding edge for new technology but this one I will wait a bit longer.

The alternator issue is a concern. I have posted here a few times about our 2004 boat and its 13.8V max alternator (and on our old 2005 lumpy water boat). With alternator only, when the engine is turned on to charge a 70% SoC bank, I get 30A max which within 10 mins is less than 20A (90A alternator). As Gibbo says in his smartgauge notes, these alternators were built to charge car batteries and not push max amps into big domestic banks. I bought a Sterling AtoB which now raises that votage to 14.4V on absorbtion and see 70A when engine started and down to say 40A after an hour (starting SoC typically 85%). I worry now it is working harder than it should and will melt. Likely I would need a 'proper' alternator if I go Lithium .........but it will be interesting to see how the range of alternators will cope.

Really keen to hear of your adventures here as you go forward.:)

Share this post


Link to post
Share on other sites
21 hours ago, dmr said:

The charge characteristic would be a huge advantage for me, not needing to get to 100% once every week or two is also a big bonus, not needing to equalise is a plus, and not having to put water in is also a plus (just been doing that this afternoon and its tedious), but cost per cycle is still a big factor and until it gets fairly close to the Trojans I don't think I will be switching to Lithium.

The engine running time is slightly less critical for me as the washing machine cycle usually takes about two hours :D

...............Dave

I expect the big issue with trojan type batts is getting enough voltage to fully charge and eq them in winter temperatures, bog standard alts and chargers won't do this.

If the batt bank can be made splittable such that half can be isolated and then fully charged/eq'd, it opens up a lot more options, but it's tooo much hassle for most people. :huh:

Edited by smileypete

Share this post


Link to post
Share on other sites

It still seems to me that they are hugely too expensive and risky. My 4 sealed jobbies last minimum 2 years full time use with zero hassle so for me it aint going to happen the vast cost simply isnt worth it. Also judging by some replies if like me you travel every day unless its plugged in in the winter then my batteries dont need to be charged so quickly and a bit of solar also helps so like they say on Dragons den.........I am out.

Share this post


Link to post
Share on other sites
35 minutes ago, mrsmelly said:

It still seems to me that they are hugely too expensive and risky. My 4 sealed jobbies last minimum 2 years full time use with zero hassle so for me it aint going to happen the vast cost simply isnt worth it. Also judging by some replies if like me you travel every day unless its plugged in in the winter then my batteries dont need to be charged so quickly and a bit of solar also helps so like they say on Dragons den.........I am out.

And how much does your travelpower cost brand new? :rolleyes:

  • Greenie 1

Share this post


Link to post
Share on other sites
6 minutes ago, smileypete said:

And how much does your travelpower cost brand new? :rolleyes:

Quite a few quid but they are independent to any form of battery. My boat will run without a TP but I must have batteries, we go several days without using the TP but batteries are in use 24/7 365 so the two items are not related. Don't get me wrong if lion batteries were in any way better at a similar price then I would have them like a shot but it seems they are very expensive for no gain and some considerable messing about.

Share this post


Link to post
Share on other sites
1 minute ago, mrsmelly said:

Quite a few quid but they are independent to any form of battery. My boat will run without a TP but I must have batteries, we go several days without using the TP but batteries are in use 24/7 365 so the two items are not related. Don't get me wrong if lion batteries were in any way better at a similar price then I would have them like a shot but it seems they are very expensive for no gain and some considerable messing about.

Yeah, but how much do your batteries cost, how long do they last, and are you just a hobby boater? :giggles:

Share this post


Link to post
Share on other sites
1 hour ago, smileypete said:

I expect the big issue with trojan type batts is getting enough voltage to fully charge and eq them in winter temperatures, bog standard alts and chargers won't do this.

If the batt bank can be made splittable such that half can be isolated and then fully charged/eq'd, it opens up a lot more options, but it's tooo much hassle for most people. :huh:

We did talk about this a couple of yearsago and I do now have a semi-split bank, two Trojans in one bank and 4 in the other. This is mostly because I am running 4 newish Trojans and 2 (now) very old ones so I wanted an easy way of checking that the old ones still have some capacity, and to isolate them quickly if they should signs of giving trouble. I did think I might explore equalisation options but I have put an external voltage pre-set on the Adverc so I use this to equalise. Only trouble is that the voltage cycles up and down (what the Adverc does) so equalisation takes longer than it should. Cycling the equalisation might even be a good think but the "hour rest" is tedious.

..............Dave

Share this post


Link to post
Share on other sites

I've now got to the end of the Marine how to link. Only took 2 days! The last bit on charging regimes did raise another issue about not 'float' charging. Out on the cut it seems very straightforward. Charge in the day to 85% SoC and then discharge overnight and start charging again the following morning. Siiimple.

...but what if you spend a large part of the winter hooked up on shore power? At the moment on shore power, I just forget about our LA's. The charger goes to float and then to 'maintain' with a 13.2V holding charge. The solar cuts in now and again in the day. The teaching on Lithiums is dont hold them full. They like it best at 40-50% SoC. There is a lot less drain on the batteries when on shore power, but there is some and this needs replaced. Rather than keep them at 85% with the charger cutting in as soon as the SoC drops, it seems better to keep them much lower than this. The link document seems to suggest holding them at 85% is bad for them. I am sure you could rig up some sort of current drain device (like an immersion heater) to take the SoC down and hold it at 40-50% but the complexity of all the relays and switching gear and then switching back to 'out on the cut' mode sounds quite daunting.

For those of you who have Lithium's, what is your strategy for winter time hook ups?

Share this post


Link to post
Share on other sites
57 minutes ago, dmr said:

We did talk about this a couple of yearsago and I do now have a semi-split bank, two Trojans in one bank and 4 in the other. This is mostly because I am running 4 newish Trojans and 2 (now) very old ones so I wanted an easy way of checking that the old ones still have some capacity, and to isolate them quickly if they should signs of giving trouble. I did think I might explore equalisation options but I have put an external voltage pre-set on the Adverc so I use this to equalise. Only trouble is that the voltage cycles up and down (what the Adverc does) so equalisation takes longer than it should. Cycling the equalisation might even be a good think but the "hour rest" is tedious.

..............Dave

If you can isolate the new ones too, then the old ones could run the loads, plus push some eq current into the new ones for a few hours (via a converter).

 

14 minutes ago, Dr Bob said:

I've now got to the end of the Marine how to link. Only took 2 days! The last bit on charging regimes did raise another issue about not 'float' charging. Out on the cut it seems very straightforward. Charge in the day to 85% SoC and then discharge overnight and start charging again the following morning. Siiimple.

...but what if you spend a large part of the winter hooked up on shore power? At the moment on shore power, I just forget about our LA's.

Use a 12V power supply for DC loads when on shore power I s'pse, they're surprisingly cheap these days. Then just leave the lithuims as they are, maybe top them up if a little low.

Edited by smileypete

Share this post


Link to post
Share on other sites
 

I've now got to the end of the Marine how to link. Only took 2 days! The last bit on charging regimes did raise another issue about not 'float' charging. Out on the cut it seems very straightforward. Charge in the day to 85% SoC and then discharge overnight and start charging again the following morning. Siiimple.

...but what if you spend a large part of the winter hooked up on shore power? At the moment on shore power, I just forget about our LA's. The charger goes to float and then to 'maintain' with a 13.2V holding charge. The solar cuts in now and again in the day. The teaching on Lithiums is dont hold them full. They like it best at 40-50% SoC. There is a lot less drain on the batteries when on shore power, but there is some and this needs replaced. Rather than keep them at 85% with the charger cutting in as soon as the SoC drops, it seems better to keep them much lower than this. The link document seems to suggest holding them at 85% is bad for them. I am sure you could rig up some sort of current drain device (like an immersion heater) to take the SoC down and hold it at 40-50% but the complexity of all the relays and switching gear and then switching back to 'out on the cut' mode sounds quite daunting.

For those of you who have Lithium's, what is your strategy for winter time hook ups?

I will be using the batteries all the time so dont think I will have that issue, however I have noticed a problem for others buying batteries from old EV packs, they arnt approved for marines use so your insurance might be void, read it on another forum just. My valences are designed for marine and submarine use so are covered

Share this post


Link to post
Share on other sites
 

I will be using the batteries all the time so dont think I will have that issue, however I have noticed a problem for others buying batteries from old EV packs, they arnt approved for marines use so your insurance might be void, read it on another forum just. My valences are designed for marine and submarine use so are covered

Be handy if the bathtub sinks :D

 

  • Greenie 1

Share this post


Link to post
Share on other sites
 

I will be using the batteries all the time so dont think I will have that issue, however I have noticed a problem for others buying batteries from old EV packs, they arnt approved for marines use so your insurance might be void, read it on another forum just. My valences are designed for marine and submarine use so are covered

Well worth repeating.

Share this post


Link to post
Share on other sites
 

Be handy if the bathtub sinks :D

 

Over the period I have owned her it has nearly happened a couple of times!! far to many openings under the water for my liking which have now been sorted :D

Share this post


Link to post
Share on other sites

Right I have finally managed to get the software working to get into my Valence LifePo4 batteries, interesting stuff to say the least, On a standard car battery charger it has happily  charged up the battery, cells balanced no issues at all. My plan is to charge all the batteries up to full, activate the balance, disconnect and then check them in a couple of weeks time. When they are in full use we will see how they go with no BMS controlling the charging just a voltage disconnect to use the power to heat an immersion heater, lets see how dangerous they really are, or how fragile they are

Share this post


Link to post
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.

×

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.