Advice on changing batteries to LiFePo please

[peterc10]

I have a 2015 Hymer B678 on a Fiat base with the Iveco 3 litre engine. I am looking to replace the 2 x 95Ah AGM batteries that we have had since new. They have never let us down (touch wood) and are still working but I expect their capacity has decreased in the 6 years or so we have used them. And I don't want them to let go suddenly when we are away in Europe. The obvious, simplest and cheapest option is to replace them with two Gels of similar capacity and size. But I have a hankering for Lithiums. And KS have a single 200Ah lithium battery that may fit snuggly in the space of one of the existing batteries leaving me with some spare storage space to fill!

We usually stop at places that do not have EHU, but on the few times it is on offer we will take it. The solar panels seem to keep us going in the South of Europe in spring and autumn and in the UK in the summer. We rarely use the motorhome in winter and if we do it is usually on EHU. We are not heavy electric users and the only thing we use our 2000W/4000W invertor for is drying my wife's hair with a 1200W hairdryer once every 3 or 4 days. When not being used the motorhome is kept on our property and is always plugged into our electrics. I have a BMV 700 battery monitor that I use regularly to check the state of the batteries and I don't think they have ever gone below 50% of capacity.

So I am looking for advice from all of you battery gurus please before I take the plunge. I don't really want to change anything else unless I have to. I do not need the very best out of the set up, as long as I am not doing any damage. I am also planning to DIY fit the battery but would not have the courage to start fitting new chargers, B2Bs etc. And I want to get it done in the next few weeks, before our planned European adventure (the first for over 2 years).

My present set up uses a Schaudt EBL 29 with choice of "lead acid" or "Gel" for mains charging. I also have 250W of solar going through a Schaudt LRM1218 MPPT solar regulator with a choice of lead acid, Gel or AGM. KS say that the charging voltage should be 14.4V and 13.2V - 13.3V float voltage. I think my Schaudt gear produces 14.4V on both lead acid and Gel settings with a charge retention voltage (is that the same as float?) of 13.4V on lead acid for 4 hours or 13.8V on gel for 12 hours. Will one or other of those be OK do you think, and if so which?

My guess is that I have a beefed up alternator but not a smart one (Lenny HB may be able to confirm that). I know the wiring is thick enough to produce at least 20A when the batteries need it, and probably more. So can I make do without having to fit a B2B?

Finally I would ask those that have KS batteries what they think of them and the company.

Many thanks for any help you are able to offer.

 

[Wagoneer]

Best advice I can offer is, if you've only got a few weeks before departure...leave it and do it when you return. By the time you've bought all the cable and stuff + installation, there won't be sufficient time for proper testing of the system.

My Hymer B544 (bought new in 2002) always charged at a consistent 14.4 volts. Sold it 10 years later with the same batteries (gel).

By comparison, my current van has a very poor charging system (CBE), rarely reaching 13.8 volts. Installed a B2B and now charges the hab batteries at 14.4 volts.

All I'm saying is, be grateful for your Schaudt charging system, it does what it says on the tin, haha !!! You've also got solar.

Go away as planned and don't over-stress yourself with last minute jobs

 

[Lenny HB]

My guess is that I have a beefed up alternator but not a smart one (@Lenny HB may be able to confirm that). I know the wiring is thick enough to produce at least 20A when the batteries need it, and probably more. So can I make do without having to fit a B2B?

Not a smart alternator and it will be an uprated one probably 160 amp. The wiring can eaisly cope 50 amps plus. You still need a B2B or you take the risk of burning out your alternator and not giving the correct charging profile to the Lithium. without a B2B you will be relying on BMS, the BMS should always be considered as a last resort, its there for prtection not to control the charging.

On your current battery set up your inverter use is just crazy. Your 1200 watt hairdryer will be drawing 110 amps out of the batteries, with lead acid batteries you should limit the current draw to the C5 rate so to take that much power you need 550ah of batteries.

 

[peterc10]

You still need a B2B or you take the risk of burning out your alternator and not giving the correct charging profile to the Lithium. without a B2B you will be relying on BMS, the BMS should always be considered as a last resort, its there for prtection not to control the charging.

I thought the problem of burning out the alternator only applied to the new smart ones. The KS lithiums have a maximum charging rate of 100A, How easy is a B2B to fit?

Can I get away with using the existing EBL and solar regulator? Looks like they have the 14.4V charging that the KS batteries need.

On your current battery set up your inverter use is just crazy. Your 1200 watt hairdryer will be drawing 110 amps out of the batteries, with lead acid batteries you should limit the current draw to the C5 rate so to take that much power you need 550ah of batteries.

Its those good old tough AGMs Lenny. 6 years and still going strong, even with my inverter use.

 

[Jimbohorlicks]

If your going to the EU ,leave well alone and go with what you know is reliable.you don't want to be installing something new and it causing a problem ,where you can't describe the problem in French ,Spanish or whatever. At least you know your current set up works .at worst case you can pay to have your wife's hair done at s hairdressers.

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[peterc10]

If your going to the EU ,leave well alone and go with what you know is reliable.you don't want to be installing something new and it causing a problem ,where you can't describe the problem in French ,Spanish or whatever. At least you know your current set up works .at worst case you can pay to have your wife's hair done at s hairdressers.

Trouble is Jim they will not remain reliable forever. From what I have heard I have been very lucky. Most AGMs don't last as long as 6 years, especially with my use of an inverter, as Lenny says. The thought of having to buy new batteries at Spanish prices does not bear thinking about.

Angela hasn't let a hairdresser touch her hair in the last 20 years. And if she can't dry her hair my only recourse will be to head back to blighty toot suite and non stop.

In addition after we get back we have some MHF rallies lined up most of which are without EHU. I have got more time to get something right before I go than I have when I get back.

 

[Lenny HB]

I thought the problem of burning out the alternator only applied to the new smart ones. The KS lithiums have a maximum charging rate of 100A, How easy is a B2B to fit?

Can I get away with using the existing EBL and solar regulator? Looks like they have the 14.4V charging that the KS batteries need.


Its those good old tough AGMs Lenny. 6 years and still going strong, even with my inverter use.

B2B fairly easy to fit if you don't fit a too bigger one you can wire via the EBL say 30 or 45 amp.
Several suppliers of Lithium say they are a drop in replacement but they are not.

You will need a new solar regulator and mains charger, your solar regulator will have as absorbtion time of several hours then drop to a float charge neither which is good for Lithium, your mains charger will have an even longer absorbtion phase.

 

[peterc10]

B2B fairly easy to fit if you don't fit a too bigger one you can wire via the EBL say 30 or 45 amp.
Several suppliers of Lithium say they are a drop in replacement but they are not.

You will need a new solar regulator and mains charger, your solar regulator will have as absorbtion time of several hours then drop to a float charge neither which is good for Lithium, your mains charger will have an even longer absorbtion phase.

I can understand that I may need a B2B to protect my alternator, so I could get a 30A one and wire it through the EBL. What would be the easiest one to fit that has a LiFePo setting do you think?

However, with regards to the solar and mains charging, I am getting confused with some of the terms being used.

The spec for the "end of charge voltages" of my LRM1218 states that for lead acid the "charging voltage" is 14.4V and the "charge retention voltage" is 13.4V for 4hr. Which of those is the "absorption phase"? The instructions also tells me that the "charge retention voltage" is used when the battery is full. I do not have the equivalent figures for the EBL, but I assume they would be about the same, but with maybe a longer float time. The spec sheet for the KS battery states that the "maximum charge voltage" is 14.6V, the "recommended charging voltage" should be 14.4V and what they call the "float charge" should be 13.2V - 13.3V.

So the charge voltage of the LRM is the same as the recommended charge voltage of the battery, as both are 14.4V. And the float charge of the LRM is only 0.1V higher than the recommended range of the battery. Or am I missing something?

To make my life simpler KS also have 120Ah batteries which are the identical size to my 2 AGMs and have the same pole terminals in the same positions and the same holding down system. So I could buy two of those. They are more expensive than the single one but would mean a straight swap with no changes needed to my wiring and also 40Ah more storage. Their spec says that the float voltage should be 13.3V to 13.6V, which matches the LRM's 13.4V in lead acid setting.

My brain is starting to hurt now..........

 

[funflair]

I would say the "charge retention voltage" will be same as the absorption phase but I am surprised at 13.4v as I thought it would be higher.

The one thing that Lithium dont like though is sitting fully charged on hook up so when the van is at home it would be worth just relying on solar and possibly using a new charger that will keep the batteries at a lower than 100% state of charge.

 

[jongood]

Like you I would like to switch to lithium but my setup works pretty well and asfaics the 440ah Gels are the originals so 19 years old. I do like to use electric kettle, toaster, hair drier, microwave, remoska etc so the problem I have is that my battery voltage starts dropping too low once I get down to about 60% ( depending on draw) and the inverter doesnt like it ( its not often a problem in Spain).

I can't find any LifePO4 batteries that arent Chinese, I'm trying hard not to support China so currently waiting for someone else ( anyone else) to start making them. There are rumours from Germany and Czech that production could start there, so I'm waiting. I also echo the folly of changing something that is working just before a big trip.

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[peterc10]

I would say the "charge retention voltage" will be same as the absorption phase but I am surprised at 13.4v as I thought it would be higher.

That figure is for the solar regulator, but I assumed that the EBL would be similar. It is 13.8V on the gel setting of the solar regulator.

The one thing that Lithium dont like though is sitting fully charged on hook up so when the van is at home it would be worth just relying on solar and possibly using a new charger that will keep the batteries at a lower than 100% state of charge.

Interesting thought. I need the batteries to work during that period because of the alarm and other background drain. I am not sure if the solar would provide enough to cope. I understand that Lithiums have a very low self discharge rate, so I do not need to worry about that. And the KS batteries control system switches charging off when their temperature reaches 0 degrees whilst still allowing them to discharge.
I am struggling to understand how I could stop the EBL charging on mains and yet still use it for the pass through of the solar charge and the 12v distribution side. Is it simply a case of unplugging the mains cable from the EBL? Then plug in the new charger and use separate leads to the batteries? What charger would be suitable for continuous use instead of the EBL do you think?

 

[Kups]

Trouble is Jim they will not remain reliable forever. From what I have heard I have been very lucky. Most AGMs don't last as long as 6 years, especially with my use of an inverter, as Lenny says. The thought of having to buy new batteries at Spanish prices does not bear thinking about.

We had to replace our hab battery whilst in Spain. Bought the replacement from Tayna Batteries and it arrived DHL to Bonterra Park/Resort in five days. UK price and around £15 for carriage. Not sure if they can deliver at that price post Brexit.

 

[funflair]

That figure is for the solar regulator, but I assumed that the EBL would be similar. It is 13.8V on the gel setting of the solar regulator.


Interesting thought. I need the batteries to work during that period because of the alarm and other background drain. I am not sure if the solar would provide enough to cope. I understand that Lithiums have a very low self discharge rate, so I do not need to worry about that. And the KS batteries control system switches charging off when their temperature reaches 0 degrees whilst still allowing them to discharge.
I am struggling to understand how I could stop the EBL charging on mains and yet still use it for the pass through of the solar charge and the 12v distribution side. Is it simply a case of unplugging the mains cable from the EBL? Then plug in the new charger and use separate leads to the batteries? What charger would be suitable for continuous use instead of the EBL do you think?

On our van I just isolate the batteries when it parked up then the only drain is the alarm off the starter battery and this is topped up by a Battery master from the LiFePO4 which would be charged by solar, we are not EBL though so not sure how you would do it.

 

[Pausim]

The one thing that Lithium dont like though is sitting fully charged on hook up so when the van is at home it would be worth just relying on solar and possibly using a new charger that will keep the batteries at a lower than 100% state of charge.

I believe leaving LiFePO4 batteries fully charged is only a serious problem when they are stored for months in that state. Fully charged on hook up is no worse than fully charged on solar, it may even be better. On hook up the charge voltage drops to a maintenance charge of 13.4-13.8V after a few hours where it will stay until next unplugged. However the solar charge will shut down every night and following day bang away again at 14.6V giving the battery no chance to settle back to a comfortable voltage.

 

[Bessy765]

Has anyone actually had an alternator burn out when charging Lithium?? I have two Transporter 100 amp Lithium. They come with a ten year guarantee no specifics about how they are to be used/stored?

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[funflair]

I believe leaving LiFePO4 batteries fully charged is only a serious problem when they are stored for months in that state. Fully charged on hook up is no worse than fully charged on solar, it may even be better. On hook up the charge voltage drops to a maintenance charge of 13.4-13.8V after a few hours where it will stay until next unplugged. However the solar charge will shut down every night and following day bang away again at 14.6V giving the battery no chance to settle back to a comfortable voltage.

Yes I can go along with what you are saying but the OP said that it stays on hook up at home and I was thinking that for example on our Victron solar I can set my own charge profile so it would never get to full charge in storage as long as it not plugged in. End of the day I think every set up is different and there isn't one size fits all.

 

[paddymcc]

That figure is for the solar regulator, but I assumed that the EBL would be similar. It is 13.8V on the gel setting of the solar regulator.


Interesting thought. I need the batteries to work during that period because of the alarm and other background drain. I am not sure if the solar would provide enough to cope. I understand that Lithiums have a very low self discharge rate, so I do not need to worry about that. And the KS batteries control system switches charging off when their temperature reaches 0 degrees whilst still allowing them to discharge.
I am struggling to understand how I could stop the EBL charging on mains and yet still use it for the pass through of the solar charge and the 12v distribution side. Is it simply a case of unplugging the mains cable from the EBL? Then plug in the new charger and use separate leads to the batteries? What charger would be suitable for continuous use instead of the EBL do you think?

I was in a similar position to you last year with 8 year old lead acid (180Ah in total) that I knew were failing.
I changed the solar regulator to a MPPT with lithium setting and a B2B (variable output, max 50A) with lithium setting. I'm no Lenny HB but I managed to do it myself. I then, after checking everything worked ok with the existing lead acids, bought a 230Ah Roamer battery with Bluetooth and fitted it a couple of weeks ago. I disconnected the charger part of the EBL101 by removing the 20A fuse on the front ( probably the same on the EBL 29) called internes landemodul. The battery now charges well on the alternator.
I doubt that I need to fit a lithium specific charger but will keep an open mind. Roamer says they are happy for me to use the EBL to charge occasionally on the lead acid setting which is 14.3V for 1 hour then down to a float charge of 13.8. By only putting in the fuse when I need to top up on EHU I can avoid leaving it on float long term which I think is best avoided.
If I wanted to leave the battery in storage mode at 50-80% I could run the fridge for a few hours and then disconnect.
I went for Votronic as Schaudt are happy to have them running through the EBL and avoids problems with having to disable the split charge relay. So far I have run the B2B at the lower current setting as I wanted to see how warm it gets ( it's stayed nice and cool) before going up to 50A..
So far very happy with it. The Roamer has integral Bluetooth so I can easily check the state of charge although the control panel still seems to give a reasonable result. I think you said you had a smart shunt which will provide information overload anyway.

 

[suavecarve]

peterc10

There is a brand new Victron smart B2B 30 amp for sale in classifieds which some idiot bought and didnt need !
He is bunging in 2 breakers to go with it, and he found the box that it came in. Purchased in January.

Victron B2B smart 12/12 -30 DC to DC charger

Another unnecessary purchase for the new motorhome as we went to put it in today and chased the wires and hey ho we have a built in B2B. Reason for not sending it back is that box has already gone in bin as got it last week. Cheapest I can find is £199...

www.motorhomefun.co.uk

 

[peterc10]

I was in a similar position to you last year with 8 year old lead acid (180Ah in total) that I knew were failing.
I changed the solar regulator to a MPPT with lithium setting and a B2B (variable output, max 50A) with lithium setting. I'm no Lenny HB but I managed to do it myself. I then, after checking everything worked ok with the existing lead acids, bought a 230Ah Roamer battery with Bluetooth and fitted it a couple of weeks ago. I disconnected the charger part of the EBL101 by removing the 20A fuse on the front ( probably the same on the EBL 29) called internes landemodul. The battery now charges well on the alternator.
I doubt that I need to fit a lithium specific charger but will keep an open mind. Roamer says they are happy for me to use the EBL to charge occasionally on the lead acid setting which is 14.3V for 1 hour then down to a float charge of 13.8. By only putting in the fuse when I need to top up on EHU I can avoid leaving it on float long term which I think is best avoided.
If I wanted to leave the battery in storage mode at 50-80% I could run the fridge for a few hours and then disconnect.
I went for Votronic as Schaudt are happy to have them running through the EBL and avoids problems with having to disable the split charge relay. So far I have run the B2B at the lower current setting as I wanted to see how warm it gets ( it's stayed nice and cool) before going up to 50A..
So far very happy with it. The Roamer has integral Bluetooth so I can easily check the state of charge although the control panel still seems to give a reasonable result. I think you said you had a smart shunt which will provide information overload anyway.

Thanks for that, very helpful.

I have been looking at Victron, but the downloadable fitting instructions assume that you know your way round motorhome electrics. Interesting that you used Votronic and that it works with the EBL. My Schaudt solar controller goes through the EBL, although I think is is just a pass through. I like the idea of the B2B working with the EBL too. Were the Votronic instructions clear as to how it fits with the EBL and did it come with the necessary connections to do so?

I don't have the smartshunt but I do have a Victron BMV 700 which shows enough info for me. The KS batteries also have bluetooth, does the Votronic stuff?

Where did you buy the Votronic stuff from please?

 

[peterc10]

peterc10

There is a brand new Victron smart B2B 30 amp for sale in classifieds which some idiot bought and didnt need !
He is bunging in 2 breakers to go with it, and he found the box that it came in. Purchased in January.

Victron B2B smart 12/12 -30 DC to DC charger

Another unnecessary purchase for the new motorhome as we went to put it in today and chased the wires and hey ho we have a built in B2B. Reason for not sending it back is that box has already gone in bin as got it last week. Cheapest I can find is £199...

www.motorhomefun.co.uk

Thanks for that. What are the fitting instructions like please and can it go via the EBL?

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[suavecarve]

Thanks for that. What are the fitting instructions like please and can it go via the EBL?

I took this out of the brand new van as well but may be useful to you so can add this to the extra breakers.

Instructions below.

Apologies some upside down

 

[paddymcc]

Thanks for that, very helpful.

I have been looking at Victron, but the downloadable fitting instructions assume that you know your way round motorhome electrics. Interesting that you used Votronic and that it works with the EBL. My Schaudt solar controller goes through the EBL, although I think is is just a pass through. I like the idea of the B2B working with the EBL too. Were the Votronic instructions clear as to how it fits with the EBL and did it come with the necessary connections to do so?

I don't have the smartshunt but I do have a Victron BMV 700 which shows enough info for me. The KS batteries also have bluetooth, does the Votronic stuff?

Where did you buy the Votronic stuff from please?

The Votronic units have clear instructions with wiring diagrams for different eventualities including through the EBL. You may need to check that your wiring is adequate cross section for the current involved. Schaudt fit chunky cables so you are probably fine especially if you can fit the B2B next to the EBL (mine went under the nearside seat with the EBL) They don't have integral Bluetooth but I think your shunt will still give you the information you need. I bought them from Roadpro with the Funsters discount. The B2B came with a temp sensor which prevents charging of lithium below freezing but I had to buy a separate sensor for the solar controller.

I'm sure you could sell your Schaudt MPPT controller to recoup some of the cost.

 

[peterc10]

Well this evening I ran a draw down test on my batteries. I did it after dark to avoid solar charging. I switched off the EHU and let the batteries settled for about 45 minutes before starting the test. All the readings I am quoting come from the BMV 700 battery monitor.

As I have said before I have 2 x 95Ah (at C20) Exide AGM batteries which are just over 6 years old.

I started with the voltage at 13.0V, and the batteries showing as being 100% full. I then switched all the lights on, which showed as approximately a 5.5A draw on my BMV. I left all the lights on for 4 hours and I then checked again. The BMV showed I had drawn a total 22.1Ah, the battery voltage was 12.4V and that the batteries were 76% full. I then switched all the lights off and left it for an hour for the battery to get back to rest. On checking again the draw was now 22.6Ah (I guess that was because of background draw), the voltage had gone up to 12.6V and the battery was now 75.7% full.

The figures from the battery percentages seem to suggest that my total battery bank capacity has dropped over a half to about 90Ah. If that is the case Lenny HB will be saying I told you so . However, the voltage figures seem to suggest that the capacity may be higher.

What do you experts think please? Are my batteries reaching the end of the road?

 

[jongood]

Well this evening I ran a draw down test on my batteries. I did it after dark to avoid solar charging. I switched off the EHU and let the batteries settled for about 45 minutes before starting the test. All the readings I am quoting come from the BMV 700 battery monitor.

As I have said before I have 2 x 95Ah (at C20) Exide AGM batteries which are just over 6 years old.

I started with the voltage at 13.0V, and the batteries showing as being 100% full. I then switched all the lights on, which showed as approximately a 5.5A draw on my BMV. I left all the lights on for 4 hours and I then checked again. The BMV showed I had drawn a total 22.1Ah, the battery voltage was 12.4V and that the batteries were 76% full. I then switched all the lights off and left it for an hour for the battery to get back to rest. On checking again the draw was now 22.6Ah (I guess that was because of background draw), the voltage had gone up to 12.6V and the battery was now 75.7% full.

The figures from the battery percentages seem to suggest that my total battery bank capacity has dropped over a half to about 90Ah. If that is the case Lenny HB will be saying I told you so . However, the voltage figures seem to suggest that the capacity may be higher.

What do you experts think please? Are my batteries reaching the end of the road?

Did you let the batteries rest after switching the lights off?
It's also difficult to know what's going on in the rest of the mh.
I think you would be better isolating the batteries from the rest of the motorhome and then connecting a known load. I wired two headlight bulbs together connected them for an hour then rested them for an hour and used a multi meter.

 

[jongood]

A little pic for those reading this and wondering what's wrong with buying Chinese.

UK homes overshadowed by monstrous shipping container from China

HOMES in Southampton have been overshadowed by a massive container ship from China and the scene has been captured in an extraordinary picture.

www.express.co.uk

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[peterc10]

Did you let the batteries rest after switching the lights off?
It's also difficult to know what's going on in the rest of the mh.

Yes, as stated in my post I let them rest for an hour before taking the final readings. In that period the voltage increased from 12.4V to 12.6V.

Everything was switched off and the draw from panels etc was very low.

I find the BMV to be pretty accurate especially when measuring current. And voltage is being read at the shunt which is connected to the battery with a 25smm cable that is only 0.5m long, so not much voltage drop.

I am not after perfect accuracy. The batteries are 6 years old AGMs and every time my wife dries her hair using the inverter they are subject to a draw of 100A, which is much higher than recommended. According to Lenny HB it is a miracle they are still working at all.

We are trying to make up for the last couple of years with a heavy programme of touring in the UK and the EU, and much of it is off grid. The last thing I want is that the batteries die on us and the hassle of sorting it out quickly and ending up with an unsatisfactory short term fix.

 

[funflair]

A little pic for those reading this and wondering what's wrong with buying Chinese.

UK homes overshadowed by monstrous shipping container from China

HOMES in Southampton have been overshadowed by a massive container ship from China and the scene has been captured in an extraordinary picture.

www.express.co.uk

Have you got the right thread jongood ?

 

[jongood]

Have you got the right thread jongood ?

Yes Martin, all the batteries mentioned are made in China. The only way that will change is if people start refusing to buy stuff from China.

Victron and others should hang their heads in shame at allowing their name to be used.

 

[peterc10]

A little pic for those reading this and wondering what's wrong with buying Chinese.

UK homes overshadowed by monstrous shipping container from China

HOMES in Southampton have been overshadowed by a massive container ship from China and the scene has been captured in an extraordinary picture.

www.express.co.uk

I am sorry but I don't see what is wrong with world trade. Shipping in huge vessels is more economical than using lots more smaller ones both in terms of money and carbon footprint.

I am afraid that I haven't got the time to wait for lithium batteries to be made somewhere in Europe nor the willingness to pay the inevitable premium price. Having said that, if I do change to lithiums, I am planning to buy a new B2B and solar regulator, both made in Germany.

 

[funflair]

Yes Martin, all the batteries mentioned are made in China. The only way that will change is if people start refusing to buy stuff from China.

Victron and others should hang their heads in shame at allowing their name to be used.

Ah it's the Lithium battery connection I actually went back in the thread to see where China fitted in and was struggling, it is still early here though.

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