41

Our onboard electrics continue to puzzle us. The current in our leisure bank dropped to 11.7V last night, indicating that our two 90Ah batteries were down to 20%. That was after running the generator for four hours in the morning and then moderate 12V use throughout the day.

Following some excellent advice on Facebook’s 12V boating group, we decided to (A) buy what the group call a Phil meter and (B) spend two days on an electrical hookup to ensure that our battery bank is fully charged. The Phil meter is a combined voltage meter /Ammeter /Power Meter /Multimeter. One of the most useful displays will be the amps going in and coming out of the battery bank. I’ll be able to see whether the problem is with our batteries or with the way we use them.

We decided to drive to a city centre aire in Narbonne to charge the batteries. Then we looked at the waves washing gently over the stone beach twenty feet in front of our front bumper and decided to stay just one more night.

Oh, how Aeolus, the Greek god of wind, must have laughed. Especially when Cynthia further tempted fate.

We both love lying in bed at night listening to a lively wind howling outside and rain pattering on the insubstantial roof inches above our heads. As we turned off the lights and climbed into bed, Cynthia sighed. “Wouldn’t it be nice if we had some rain and wind tonight?” I can’t remember rubbing a magic lantern, but Cynthia’s wish came true in spectacular fashion.

We started off our night in our rear double bed next to our broken window held together with yards of duct tape. The window behaves itself most of the time, but in a strong wind, the broken edges rub together serenading us with sleep depriving squeaks and creaks. The window misbehaved last night. Squeaks and creaks increased in volume as the wind speed picked up. We gave up at midnight, pulled down our over-cab bed and climbed into what we hoped would be a more peaceful area of the Hymer.

We were woken three hours later by the wind howling and moaning as it shook the Hymer violently from side to side. Windblown waves crashed from the shallow bay next to us over a stone access road, our only means of escape. A small fishing boat which has been in the same position high on the rocky beach for the last few weeks had disappeared, washed away by the powerful spring tide. Another had been driven from its centre bay mooring onto the shore.

As we lay in bed bracing ourselves against the bed rails, the Hymer lurched again. The motorhome can withstand a substantial gale if it’s parked nose to the wind, but we ran the risk of flipping over if gusts hit either side. I needed to go outside to check the wind direction. I suspected I was over cautious. I don’t know anyone who has been in a motorhome when it’s overturned. On the other hand, I don’t know anyone who parks in a storm on an exposed beach in the windiest part of France and tempts fate. I couldn’t afford to be complacent.

Getting out of the Hymer was more difficult than I expected. The wind pinned the habitation door shut. Climbing out through the driver’s door would have been easier, but two awkwardly shaped dogs decided that they needed to relieve full bladders. I had to brace my back against the habitation door frame and push as hard as I could with both arms to open a gap wide enough for both dogs to slip through.

Less than a minute outside was enough to soak the three of us. Twelve-year-old Tasha was bowled over by the gale hitting the Hymer head on. We couldn’t manoeuvre into a better position, and the wave washed road blocked our escape. We lay in bed for hours listening to the wind howl, cringing as gust after gust rocked our Fiat suspension. It wasn’t one of our most restful nights in the wild.

We woke to a different world. A brilliant sun shone from a clear blue sky. Not a breath of wind rippled the mirror-smooth lagoon. We didn’t want to spend such a beautiful day crammed into a claustrophobic aire so we could charge our batteries. We decided to stay another day.

The monitor indicates that our battery bank is nearly empty

The monitor indicates that our battery bank is nearly empty

A boat deposited on the shore by the howling wind

A boat deposited on the shore by the howling wind

This boat disappeared in the storm. The access road in the background was hidden by breaking waves.

This boat disappeared in the storm. The access road in the background was hidden by breaking waves.

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Click Here to Leave a Comment Below 41 comments
Malcolm - March 5, 2018

So.. where’s the wind generator when you need it most? Get a spiral type rather than blades as the don’t blow apart in storms, but are less efficient than blades but quieter, making no more noise than the actual wind howling.

Reply
    Paul Smith - March 5, 2018

    I think a wind turbine would have had a nervous breakdown in those winds. I’m not a big fan of wind generators. I’ve yet to see one which looks neat and tidy, and the vibration through the guide wires is enough to make a strong man cry. There’s plenty of sun in the south of France, so I’ll do the sensible thing and upgrade our solar.

    Reply
Keith - March 5, 2018

Hi Paul,

I don’t think there is anything baffling – you are just not charging the batteries sufficiently. Lead acid doesn’t like to be discharged and it certainly doesn’t like to go below 50%. The 4 hours on the generator probably only charged the batteries to 80% and then you were using them throughout the day.

The capacity is probably fixed by the physical space available so you must control your use and increase your charging. LEDS everywhere, no inverter if possible, gas for the fridge (if possible). In the winter the only cost effective charging is from the mains because it will take at least 7 hrs to fully charge your batteries. If the cost of the aire outweighs 7 hours of petrol for your genny that might be an option but of course they are noisy and need servicing. Obviously in the summer solar is the way to go. But you know all this – you used to own a narrowboat.

Reply
    Paul Smith - March 5, 2018

    The situation IS baffling, at least to me. Yes, I used to own a narrowboat and lived completely off grid for long periods. This is also our second winter in the motorhome in the south of France. Our circumstances and our electrical usage are similar this year to last year. We were fine with our charging regime last year. They are AGM rather than lead-acid batteries so they can handle discharging slightly better. The batteries were also new in November, so they should still be holding a charge.

    All the internal lights are LED, there’s no inverter and the fridge is a three-way, so it uses gas when we are parked and not plugged into the mains.

    Maybe the only solution is to stay on an aire regularly but, to be quite honest, I would rather rake my testicles with barbed wire. Maybe I just need to fill the roof with solar panels and hope for clear skies.

    Reply
      Jos Evens - March 7, 2018

      Hallo Paul,

      didn’t you change your alternator too, last year? Is the tension high enough for AGM? It should be close to 15V., as you probably know from your “James”period.

      Reply
        Paul Smith - March 7, 2018

        Thank you for thinking that I know a little bit about alternator voltage after owning a narrowboat for six and a half years. I don’t. I’m going to have the electrics thoroughly reviewed as part of the warranty work I hope to have done next month. I’ll add an alternator voltage check to the list.

        Reply
    Malcolm - March 5, 2018

    Tend to agree.. not long enough charge. A single stage charger (which will only get them to 80-85%) rather than a 3 stage smart charger. Small battery bank of just 180 Ah. Old technology batteries.
    You will never near the holy grail without spending money on Lithium batteries, a smart charger, incl MPPT, and more solar…. all of which could be transferred to the boat later when you sell the Hymer (and refit the existing kit)

    Reply
      Paul Smith - March 5, 2018

      I’ve considered Lithium batteries. Have you seen their cost? The most frustrating part of this at the moment is not having a decent battery monitor on board. A rarely allowed my batteries to go below 90% on the boat. With my Smartgauge monitor, I was able to check the capacity remaining quickly and easily. Maybe I need to install one in the Hymer too.

      Reply
Malcolm Wood - March 5, 2018

Try looking at narrow boat Jono, this chap has installed Lithium to his new boat and in the most infinite detail describes the , both installation output and cost.

Worth a look

Regards

Mal Wood

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Bob - March 5, 2018

I would rather rake my testicles with barbed wire. Picture please just to keep us amused.

Reply
    Paul Smith - March 5, 2018

    In consideration of those of a delicate nature, or anyone about to eat, I think I’ll refrain. I think you understand though how much I dislike living in a motorhome with paper thin walls and being parked four or five feet away from another motorhome with equally thin walls. I like my peace and quiet, so I’m going to do whatever necessary to get my electrical setup to work.

    Reply
Brian Ewart - March 5, 2018

Can I just put in , your current measured in Amps, a measurement of flow, it did not drop to 11.7v thats volts which is electrical pressure. Low pressure ( voltage ) will inhibit you flow (amps). By all means have more metering it will tell you, once you have sorted out whats flow and pressure, what going on.Additionally your loads are rated in watts which is the rate they use energy. Pretty certain you know this. AGM are lead acid just up market. Lithiums would be better, solar with MPPT a very good idea wind naw, not effective, if you stay with your AGM a 3 stage smart charger good idea. All Lead acids have a real issue getting fully charged, first bit easy middle oh well last bit ( 20% ) really difficult, basically they charge on an exponential basically to get then to work you need to keep them pretty full and then don’t go say below 50%. This advice is general, but I was in electrical engineering but no expert in this field. Bottom line liFep04 Solar MPPT and do some research and remember Voltage is electrical pressure and current is electrical flow and you use in watts = amp hours out of the battery system.

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    Paul Smith - March 6, 2018

    Thanks for the advice Brian. Lithium batteries both fascinate me and scare me senseless. I’ve read articles about the long-term cost savings and convenience offered by Lithium batteries, and I’ve read articles like this one which warn that Lithium batteries may well be more trouble than they’re worth. How would you respond to the issues raised in this article, or to this Motorhome Matters forum post?

    Reply
      Brian Ewart - March 6, 2018

      I have read most, albeit quickly,both articles, actually it is the boss ladies birthday so !!! you understand. I will re read and give serious thought. Immediately, I don’t factor weight not a question for me. LiFePo4 is the only viable lithium technology yes others have had problems. A system that is incorrectly fitted/ poorly designed ie wrong cables then any battery will cause a problem and I have seen burnt out cars caused by lead acids! From memory there is a suggestion victron can do 4000 cycles and achieve deep discharge,hmmmm, I have doubts it will do both and then last 12 years, the accepted wisdom is lead acid need charge management and DoD of 50%, if you go to 80% lead acids life span will drop significantly max life span is generally attained with DoD of only 30%,hardly practical hence 50%. NiFe are even better but probably due to other criteria not suitable to an RV ( motorhome ? excuse please). So until I put more thought into it for you , as you have concerns, either good ( and they are not all good and price not necessarily a guide) AGM or GEL with 3 stage charger ( as suggested ) stick to DoD of 50% (if space available maybe a bigger bank well biger Ah batteries at least more Ah! compensates for for lower DoD-you take less from more) Solar+MPPT,I suggest an new energy audit- match load against supply and find a quality solar system that will match you needs.As you(hopefully) are in a sunnier location you will find it should work very well.

      Reply
        Paul Smith - March 7, 2018

        Our location is sunny, but not particularly warm yet Brian. We’re on France’s Mediterranean post near Narbonne. My single solar panel generates 5 amps on a good day. On most days at this time of the year, the peak input is 2-3 amps.

        Reply
          bgewart@hotmail.com - March 7, 2018

          Dear Paul,
          Just read Grahams comment and you response, seems you have it sussed ! Go back to Nb philosophy get a bigger bucket ( thanks Graham used that simile when teaching it ). Just using Ah’s -with 2 x 90 Ah units 50% DoD is hmmmm 90Ah which may not be sufficient for you needs , 2 x 210 Ah units 50% DoD is 210 Ah. Your into Solar just need a slightly bigger more efficient set up ( will now assume you do use MPPT) . Stick at mo to AGM if that’s what your happy with ( or GEL ), support in you situ is an issue. ( I assume now smart charger see Malcolm) LiFePo4 are fine, quite safe from what I’ve read ( follow Jono as suggested ) and costs will come down. In 10 yrs you will laugh at any one on lead acids. Keep eye out for what NiFe is upto. For solar, sunshine is all you need, brilliantly sunny day here at mo( Shropshire) but I still envy you and when in doubt I have another glass of a soft red all problems seem better after the second.
          Enjoyed the interchange, safe travelling.

          Reply
          Paul Smith - March 7, 2018

          In ten years I might well be prepared to consider Lithium. There will be enough boaters and motorhome owners with Lithium installations approaching their advertised end of life. I wonder how many will still be up and running? I agree; a bigger capacity leisure bank is needed, and more solar to keep it happy.

          Reply
Dave Goodfield - March 5, 2018

I think I would rather stay on a Campsite rather doing the barbed wire thing but then but then if you are into that…….. 😇

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    Paul Smith - March 5, 2018

    I probably exaggerated ever so slightly, but you get the picture. Mind you, it’s a picture you probably want to erase from your mind.

    Reply
Neil - March 5, 2018

Hi Paul,
You could try conditioning/equalizing your batteries by fully charging on mains hook up then charge for 8 hours at 15.5 volts as recommended by lifeline batteries, for this you will have to buy a charger capable of being set at that level, but it will pay for itself in batteries lasting much longer.

Cheers Neil

Reply
Alan Briscoe - March 5, 2018

Might be best to separate your batteries so whatever charge you put in will at least give you one battery fully charged which is useful rather than a larger one (ie two connected in parallel) which is nearly flat. I discovered this when I had two leisure batteries which a 80w panel could never charge properly. Best wishes
ps. If you do manage to get one battery fully charged do not connect it to the other flat one!
Alan

Reply
    Paul Smith - March 6, 2018

    Thanks, Alan. I’ll bear your suggestion in mind.

    Reply
Graham Mills - March 6, 2018

Paul,

It all comes down to remembering that those batteries are a bucket. You fill the bucket with water (charge) use it and have to refill it (recharge). Like filling the bucket you can fill it quickly at the start but to get it brimming full you have to do the last bit slowly so none is split. The first bit of charging a battery is quite quick up to about 75% the last bit is slow and it slows even more for the last 10%.

To give you an idea batteries a 200Ah bank charged with a 20A charger discharged to 50% of their capacity will take 7 ¾ hours to fully charge. The last 25% will take 5 ¼ hours and the last 10% will take 3 ¾ hours over half the total charging time.

If you do not fully recharge them every time you recharge the batteries will sulphate and lose capacity and die.

Knowing you as I do I suspect that 200 or 300Ah of Lithiums with the full Battery Monitoring system would be the best long-term result. The do not mind being undercharged so you can charge them enough for the day and they last a very long-time. Yes they cost but how many sets of batteries has the Hymer had, how many sets did James have 🙂

I would suggest for you the Victron Lithiums with their full Battery Monitoring system.

Graham

Reply
    Paul Smith - March 6, 2018

    As I mentioned in a reply to another comment on this post Graham, I would be more than happy to consider lithium batteries if they had a proven history of reliability and long life. From what I have read so far, I understand that the long life advertised for Lithium batteries depends on optimum circumstances, which we all know never happens either on a boat or a motorhome, especially if they are used as full-time homes. The life expectancy also appears to reduce significantly is the system has solar panels trying to force amps into the Lithium batteries. They don’t like being charged constantly. A further problem is with the existing electrical management system, the wiring and, in many cases, the inexperienced companies who install them.

    I am FAR from being an expert, but I’m pretty good at searching for information. My research so far has indicated that, while Lithium batteries may well be the way to go for owners of liveaboard boats and motorhomes in the future, there’s a great deal of work to do before the average guy on the street – me – can benefit from them.

    When I consider lithium batteries’ initial cost, wiring and power management upgrades, the potential problems when trying to integrate them with a solar array, and the difficulty in finding an expert to work on them if they go wrong when I’m out of the UK, sticking with a decent bank of AGM batteries is the way to go for me.

    I think I ended up with a pretty good electrical set up on my narrowboat. I had a bank of four 160Ah AGM batteries powered by a 300W solar array and my 70 amp alternator. My leisure bank rarely dipped below 90%. With that regime, I expect the new owners to get many more years from them.

    I admit that we haven’t managed our power quite so well in the Hymer. Limited capacity, one small solar panel and infrequent driving to charge the batteries via the alternator have meant that the batteries haven’t been treated well. It’s all part of the learning curve though. I’ll get there eventually.

    Reply
Jeremy Toms - March 6, 2018

Paul
Hate to say this but if you’ve taken your AGM’s down to 20% capacity, then they are in all probability toast. Even AGM’s suffer from sulphation of the plates and at that level you ran the risk of the plates buckling. What you should do is get your meters calibrated so that 0 on the meter equates to 50% of the capacity. That way you reduce the risk of over discharging your batteries. Best done with new batteries and a decent programmable power meter.

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    Paul Smith - March 6, 2018

    Thanks for the advice Jeremy. The truth is that I don’t really know what’s been going on with the batteries. The Hymer’s cabin control panel has shown some very strange readings recently. I like the idea of calibrating 0 to 50% capacity. That makes more sense to me than the way it’s probably set up at the moment.

    I’ve been on an EHU for the last 48 hours. We’re coming off it today. In a couple of hours, I should be able to tell if the leisure bank is holding a charge, providing the gauge is working properly of course.

    Reply
      Alan Hutty - March 7, 2018

      Not sure how your system is set up but I have an intelligent charger/controller which prevents my batteries being discharged past the manufacturer’s recommended percentage level. Wind generators are a hassle for a motorhome. Let’s wait and see what Tesla comes up with in the next year or so.

      Reply
        Paul Smith - March 7, 2018

        I think that “intelligent” is going to be a stretch for my fifteen-year-old electrical system. Cerebrally challenged would be more appropriate, especially given its recent performance. I think that wind generators are a hassle whether they’re on boats or motorhomes. More solar is the way to go for me.

        Reply
Richard Langdon - March 7, 2018

Hi Paul, i was given a tip by an electrician when i first bought my narrow boat which has worked ok for me. Do not let your batteries go lower than 12.1v

Reply
    Paul Smith - March 7, 2018

    12.1V is about 55% full according to my AGM battery chart, so the percentage makes sense.

    Reply
Tim Stewart - March 7, 2018

Hi Paul,

my advice, for what it’s worth, is to stick with AGM, or something similar, until you both decide exactly what you going to do, permanently! When you have one boat (I hope), then it might be time to think about a more robust battery storage system.

When you have parted company with the Hymer and one boat, then I would recommend looking at:

http://www.odysseybattery.com/marine_batteries.aspx

with suitable monitoring and charging, obviously.

With respect, your history with electrical gubbins is not stellar, so KISS. :o)

Regards Tim

Reply
    Paul Smith - March 7, 2018

    I think that the only time I’ll really know what I’m going to do permanently is when I’m laying in a wooden box being lowered into a deep hole.

    I’m inclined to stick with AGM, increase the capacity and add at least one more solar panel.

    Reply
      Tim+Stewart - March 7, 2018

      In my experience, AGM worked very well in our narrowboat. At least it’s proven, reliable and reasonably cost-effective. They work well with solar.

      Let others spend the money and gain long-term experience of lithium batteries.

      Take care.

      Regards Tim

      Reply
        Paul Smith - March 7, 2018

        Couldn’t agree with you more Tim. Let others hack a path through virgin wilderness. I’ll wait until the lithium track record is as smooth as a metaphorical motorway.

        Reply
Keith - March 7, 2018

I find this site an excellent resource.

http://www.aandncaravanservices.co.uk/agm-batteries.php

Is this the problem:

Hymer fitted AGM batteries as standard habitation area units as early as 2013, without any regard for the none AGM charger that it was paired with. Their publicity said the AGM batteries would be fine on a Gel setting.
They weren’t.
As a result many prematurely failed AGM batteries were experienced and Hymer rushed through a charger that did have an AGM optimised setting.

But AGM batteries in Motorhomes continued to have short lives.
Only in 2017 did Hymer begin to address the problem of the vehicles Alternator only being able to charge at a none AGM optimised 14.4v, rather than the necessary 14.8v. ?

Reply
    Paul Smith - March 8, 2018

    Yes, I’ve read some information posted by this guy before Keith. He certainly appears to know his stuff. I have a list of topics to discuss with Oaktree Motorhomes when I take the Hymer back to have some warranty work done next month. This will be one of them. Thank you for the research you’ve done.

    Reply
James Valentine - March 7, 2018

Hi Paul. We switched to lithium (LiFePO4) on our narrowboat this winter as we needed to replace our five lead acids and were alerted by a fellow boater to two second hand Valence U-Charge U27-12XP 130Ah packs at the ideal time. They’re about £1400 each new and we got them for £350 each, with 60 cycles on them according to the internal BMS. They were originally in an electric delivery van project (with 20 other packs) but the firm went bust. I wired them in parallel.They balance themselves internally and show their status with an LED which normally flashes green every 20 seconds.

Our boat is gas-free (electric cooking, built-in diesel generator) and we have high power demands – we routinely use a 1200W kettle on our inverter. We are not typical users (which itself justifies the higher outlay).

For us, our packs have freed us from many of the headaches of lead acid leisure batteries which I summarise as:

– slow to charge which wastes diesel, yet:
– having to think about charging up to 100% frequently except with mid-summer solar
– sulphate when left discharged
– can’t deliver much current (without a big bank of them)
– self discharge over time
– less available capacity: should only be discharged to 50% of capacity to preserve life
– heavy

though they they’ve given us other challenges:

– Resting voltage doesn’t vary much as you drain them: you can’t really tell the state of charge (at least between about 10% which is too low for comfort and 80%) from the voltage unless they’re under heavy load – a battery monitor with Ah counter helps. We don’t worry too much as I’ve installed some protective circuits which stop them being completely flattened by disconnecting the loads and turning off the remote switch of the inverter if the voltage goes below about 11.5v
– should not be held at high voltage – a problem when charging off the alternator during long cruises, although lead acid float voltages around 13.6 are fine
– prefer to be left partly discharged
– ruined if charged (even a few amps of solar) when below 0 deg C so in the recent cold weather we ran our Webasto which warms up the engine bay before thinking about charging.

We think of our lithiums as fine china plates. They should last well (good for conservatively 3000 cycles – eight years if we flattened and charged them every day) unless the resting voltage of the pack drops below 10v. Then it’s game over, like dropping a plate. One bad flattening and that’s basically it. I’m going to add some protection from high voltage too, which will quickly kill our batteries as well. We accept that we’re part of our battery management system!

If you want to know anything specific about living practically with LiFePO4 I’m happy to answer questions here.

Reply
    Paul Smith - March 8, 2018

    Thank you for an illuminating post, James. You say that you have high power demands but with these two lithium batteries, you only have 260Ah at your disposal. How do you manage with so little? Have you upgraded your wiring to handle the higher current available with Lithium batteries? I understand that inadequate wiring has been a cause of fires in the past.

    A system like this is fine for someone like you who appears to know how to mollycoddle his fine china plates. I’m more of a squaddie’s aluminium mess tin kind of guy. I want something which can handle the knocks, bumps and vibration associated with the constant movement of either a boat or a motorhome. I don’t want to have to worry constantly about the battery bank’s comfort and diva demands. My 640Ah AGM leisure bank was pretty much bomb proof. All I needed to do was to make sure that they were well charged. My 300W solar array handled that magnificently in the spring, summer and autumn months. I had to run my engine for about an hour and a half each day during the winter months. I didn’t have any electrical worries. I probably didn’t use as much electricity as you, but I ran a fridge constantly, watched a couple of hours of 230V television each day, vacuumed daily, and had MacBook and phone chargers plugged in 24/7.

    I’ve discovered that motorhome electrical systems are a little more delicate than they are on a narrowboat. I don’t want to have to try and balance an already delicate system with equally delicate lithium batteries. A bank of lithium batteries going down would be catastrophic for us when we’re spending most of our time away from where the batteries would be fitted. And if we had a problem with them, we couldn’t visit the closest motorhome repairer to have an emergency set of lead-acid batteries fitted. The whole system would need altering.

    I hope that your lithium batteries last you for many years. I don’t have the knowledge necessary to keep them fit and healthy, and I don’t have the money to rectify the damage if they go wrong. Thanks again for the information, but I will stick with AGM batteries for a few years yet.

    Reply
      James Valentine - March 15, 2018

      Re-reading what I wrote and I realise it makes me look like a bit of a fanatic!

      Our old bank was 5 x 12v Exide ER550 115Ah (£500 for 5, good for three years tops) = 575Ah so 287.5Ah usable capacity following the 50% discharge rule. We were managing on much less than that when we replaced them due to age, but were wasting diesel to prop them up.

      Our new bank is 2 x 130Ah LiFePo4 (£700 for 2, good for at least 6 years conservatively), but using 80% capacity, so more like 208Ah available: not horrendously different.

      I think the solar helps a lot (2 x 260W panels) and not having to condition them with long absorption charges saves us a lot of money – easy to overlook how much – we fill up nearly half as often against the same time last year. We charge them like we would a mobile phone – a quick top-up for half an hour when we’re about to go out puts 30Ah+ back on, for example. No need to leave them charging for hours to protect their lifespan.

      Our main 12v wiring is 300A spec throughout with a 300A mega fuse as the final protection from disaster, but my logic here is that other than a dead short through shoddy wiring, the overload limit of our inverter caps the maximum possible draw from the batteries – nothing connected to our 12v system could possibly draw as much power as our 230V appliances. Our old bank of lead acids could also deliver a lot of current so I think the fire risks are similar there.

      Vibration should be no problem with lithium packs, but I’d forgotten that you have to leave the van for long periods. In those circumstances, if you completely isolate the packs they will hold charge much better than any lead acid, though ideally you should leave them partially discharged.

      I would actually advise not buying more capacity in your lead acid bank – if you use that capacity you’ll simply have to spend more time charging them and you’re more likely to ruin them through repeated undercharging. Better to have two that you look after really well – consider upgrading your alternator charging by putting an Adverc in and try to get your batteries charged right up as often as you can afford. Your comparison with your boat engine charging is maybe unfair – the output in A of your van’s alternator might be far less than your boat’s was. Is your built-in mains hook-up charger a three/four-stage one? Can you see when it’s got to the float stage? Maybe your new meter will show you when the voltage and current drops. That’s when I’d call them fully charged.

      I have left our old lead acid bank in place – they’re needed for trim at the moment as the LiFePo4s are so much lighter. There’s nothing stopping me reconnecting them in an emergency and I wouldn’t have to change the system to do so. You would be able to swap the batteries for lead acids you picked up anywhere if you had to.

      Reply
        Paul Smith - March 16, 2018

        Thank you so much for such a detailed reply James. The logic behind increasing our leisure bank capacity is not so that we have more power to use. We will continue to use the same amount of power so each of the three batteries in the bank will suffer a lower percentage discharge on a daily basis. I will also add more solar so that we can take advantage of the constant but weak Mediterranean winter sun.

        Good point about the size of our Hymer’s alternator. I will have its output checked. Actually, I’ll be able to check myself once I have the new monitor fitted.

        Reply

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