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LeadAcid replace with Lifepo4 in campervan - split charging.

Puiumeu

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I am building a 12v 280ah lifepo4 battery as detailed in this forum.
I currently have Lead Acid Deap Cycle Batteries connected to a CBE charge controller and MPPT (set for Lead Acid).
The battery will charge from the van, shore power or solar. Most of the time it's full from solar alone.
When I replace the battery with a Lifepo4 with JBD/Overkill BMS, I should change the MPPT controller to Lithium but do I need to change the shore and van charging to a system that supports lithium or will the BMS be able to manage the charge from the CBE charging even though it does not support lithium.

If not should I just replace the MPPT with the DC-DC unit Will recommends for an alternator system as to date I have never used the shore power.

Thanks in advance and sorry for what is possibly a silly question...
 
I guess you are in the UK or EU.
A few questions.
What amount of solar panels and what solar controller?
Is the existing engine charging via the CBE internal relay?
Is the vehicle professional build or diy? What vehicle?
What is the model number of the CBE mains charger?
What existing high current fuses do you have at the engine and service battery and what is the cable size?

I suggest you consider b2b chargers from the Victron, Votronic, or Sterling Power. Renogy units have poor support in Europe and from reported issues seem unreliable.

It's possible cables, fuses, need upgrading and modification to the CBE units

The BMS is a last resort protection device not a charge control .

Mike
 
I guess you are in the UK or EU.
A few questions.
What amount of solar panels and what solar controller?
Is the existing engine charging via the CBE internal relay?
Is the vehicle professional build or diy? What vehicle?
What is the model number of the CBE mains charger?
What existing high current fuses do you have at the engine and service battery and what is the cable size?

I suggest you consider b2b chargers from the Victron, Votronic, or Sterling Power. Renogy units have poor support in Europe and from reported issues seem unreliable.

It's possible cables, fuses, need upgrading and modification to the CBE units

The BMS is a last resort protection device not a charge control .

Mike
Hi Mike,

Thank you so much for your reply.

Yes in Edinburgh UK.

With respect to your questions.

What amount of solar panels and what solar controller? 2*150w flexible, spark 40A MPPT.

Is the existing engine charging via the CBE internal relay? As far as I am aware, I would need to check, see later comment. The CBE stuff all looks a little "toy" to me and the battery always appears to be fully charged by solar...

Is the vehicle professional build or diy?
It was supposed to be professional but is a bit of a mess to be honest, was the personal vehicle of a van conversion company but sold privately, having now had time to look under the hood we appear to have been sold a busmans holiday. The vehicle was only really used for campsites and the owner "converted it for us for off grid before we purchased"

What vehicle? VW Crafter LWB 2011.

What is the model number of the CBE mains charger? Its a CBE PC180 System with CB-516 Charger. I believe the Ds300

What existing high current fuses do you have at the engine and service battery and what is the cable size? Still reverse engineering the mess but planning to rewire and add circuit breakers.

I will look at the b2b solutions you listed and would appreciate any advice you could give me to making this more usable and safe.

Thanks in advance.

Al
 
Travelling about at the moment so will 'drip feed' info over the next few days.

The solar controller and panels you have, are unfortunately, not the best. The spark 40A is not a mppt, is is a fake, just a low cost pwm. (£12)
Not the best for lithium as the settings may not be optimum.
I suggest changing for a quality mppt controller, Victron Smart 100/20 is OK for 300 watts of panel.
Although the panels are working at the moment unless you're very lucky they will fail within 24 months.
Sorry for the negative comment but your converter did not do you any favours fitting this solar setup.

The connections from the batteries to ds300 the should be via a 50A fuse ar the battery end of the cable. Do not consider dc breakers, most of the breakers available in the UK are poor quality, keep over current protection using fuses, more on this later.

On a 2011 crafter use a 30 amp b2b for engine charging. Victron or Votronics

Useful 'shop' for everything you may need is 12vplanet.

The ds300 has a built in combining relay that allows engine charging.

The lithium setup you intend to fit will need modifications to the ds300.

More suggestions in a day or two.
Note much on this forum is relative to USA RVs that tend to use significantly more battery energy than Euro vans.

Mike
 
@mikefitz,

Thank you so much I look forward to your additional posts and insight.

I was under the impression that the spark mppt 5040 was a voltronic copy and was a true mppt.


I am in total agreement that the supplier did us no favours.

I would be interested in what would be my best, short term and safe solution for making this as usable as possible and ready for the Lifepo4 with BMS when it arrives.

I am reasonably competent but need your expertise so I have the safest solution.

There is currently no isolation of the cells or battery so your advice is appreciated.

Thanks in advance.

Al.
 
spark mppt 5040
Sorry , you are correct, I was looking at a different model. The unit in your link is a MPPT.

The CBE PC180 and DS300 is a common install in professional built motorhome and although the PC display panel now has updated versions, the basic DS 300 is still used. Its quite a good system and is adequate for the majority of users who will stay most of the time on campsites.

The battery charger is designed for lead acid and GEL batteries. The lead acid setting could be used for lithium if you accept the longish absorption time.
It operates as follows, charges to target volts, (max current 16 amps), 14.1 volt, has a fixed absorption time of 90 mins, drops to float, 13.5 volts for 10 hours then goes to standby until the volts drop below 13 volts.
I think this is usable for lithium on an infrequent basis, the absorption duration is perhaps a little long.

Engine charging is controlled by a relay in the DS300.The engine battery is connected to the +B1 terminal, the service battery to the +B2 terminal and the common negative to the -B2 terminal. The DS300 detects that when ignition is active and the engine battery volts are over 13 volts and switches the internal relay, connecting +B2 to +B1.
This is usable for lead acid batteries but replacing the service battery with lithium may/will cause issues,
there is nothing to limit the high current the lithium batteries may take, ( perhaps damaging the internal relay)
the starter battery voltage may not be suitable,
there is no termination of charge when the lithium battery is full.

When up dating the system, connecting the b2b and solar charger direct to the service battery via suitable fuses is preferable to using the DS300 relay. The relay activation can be disables by cutting out the resistor, 2, in the picture ( resistor R37).

On the DS300 the terminal +B2 will still be connected to the service battery and + B1 to the engine battery but solar and engine charging are now direct to the service battery.

Suitable b2b chargers are the Victron Orion12 12 30, the Votronics VCC121230 or the121250, Sterling Pro 121230 or 121260

You may need to update cables and fuses, the instructions for the chargers will advise.

General diagram showing connections of chargers ( the CBE mains charger is connected via the DS300, replace with an alternative charger as shown if required). The Victron shunt or equivalent is for an optional battery monitor.

ds300mod.jpg
diy solar8.jpg

Mike
 
@mikefitz, all done working great, thank you so much could not have done it without you.
Stirling B2B works great, just wish I can trickle charge the van as the battery always shows low on the PC180.. Noticed the new Stirling b2b's support vehicle charging...
 
I was following this topic as I had a similar installation: Carthago C-Compactline i 143 LE (2021) with CBE DS300 distribution board, PC 180 panel, CB 516 charger, Schault Booster WA121525.

I have replaced original 80 Ah AGM leisure battery with 2 x 100 Ah LiFePO4 batteries and I was looking into splitting the batteries and charging, separating the lead acid and the lithium batteries.

Yesterday I have opened DS300 and on my version the interconnecting relay (no.1 in above photos) and resistor 37 (no. 2) are not there from factory. Upon measuring the voltages over B1 and B2 looks like the batteries are separated while the engine is running.

Initially the CB 516 charger was supplying directly to leisure batteries B2 and only 2A to starting battery B1 through a zenner diode.

I have moved CB 516 charger from B2 to B1 and set it up for lead acid battery and I have added a lithium charger Xentec LBC500S-15 set up for lithium battery over to B2. Now, when shore power is connected, I charge both starting battery and leisure batteries with their dedicated chargers.

Finally, I set up Schault Booster WA121525 for lithium battery.
 
Sorry , you are correct, I was looking at a different model. The unit in your link is a MPPT.

The CBE PC180 and DS300 is a common install in professional built motorhome and although the PC display panel now has updated versions, the basic DS 300 is still used. Its quite a good system and is adequate for the majority of users who will stay most of the time on campsites.

The battery charger is designed for lead acid and GEL batteries. The lead acid setting could be used for lithium if you accept the longish absorption time.
It operates as follows, charges to target volts, (max current 16 amps), 14.1 volt, has a fixed absorption time of 90 mins, drops to float, 13.5 volts for 10 hours then goes to standby until the volts drop below 13 volts.
I think this is usable for lithium on an infrequent basis, the absorption duration is perhaps a little long.

Engine charging is controlled by a relay in the DS300.The engine battery is connected to the +B1 terminal, the service battery to the +B2 terminal and the common negative to the -B2 terminal. The DS300 detects that when ignition is active and the engine battery volts are over 13 volts and switches the internal relay, connecting +B2 to +B1.
This is usable for lead acid batteries but replacing the service battery with lithium may/will cause issues,
there is nothing to limit the high current the lithium batteries may take, ( perhaps damaging the internal relay)
the starter battery voltage may not be suitable,
there is no termination of charge when the lithium battery is full.

When up dating the system, connecting the b2b and solar charger direct to the service battery via suitable fuses is preferable to using the DS300 relay. The relay activation can be disables by cutting out the resistor, 2, in the picture ( resistor R37).

On the DS300 the terminal +B2 will still be connected to the service battery and + B1 to the engine battery but solar and engine charging are now direct to the service battery.

Suitable b2b chargers are the Victron Orion12 12 30, the Votronics VCC121230 or the121250, Sterling Pro 121230 or 121260

You may need to update cables and fuses, the instructions for the chargers will advise.

General diagram showing connections of chargers ( the CBE mains charger is connected via the DS300, replace with an alternative charger as shown if required). The Victron shunt or equivalent is for an optional battery monitor.

View attachment 62055
View attachment 62056

Mike
Well Mike, you certainly seem to know your stuff. I'm in a similar situation. DS300 + AGM, and want to update to DC-DC and LiFePo4.

I've mostly chosen that I'm going for a Victron Orion - what I'm unclear on, is whether I need an isolated or non-isolated version.

I put my multimeter on the house AGM -ve terminal and a bit of the chassis, and discovered that they are connected one way or another.

But might that just be from them both being connected to the DS300? The engine wasn't running, so I'd expect the relay to be "off", but maybe the -ve side of both batteries still connects in some way?

I appreciate I could disconnect both batteries from the DS300 to test, but it's hard to access right now, and I'm reluctant to rip it all out until my lithium arrives.

Is one "better" than the other regarding isolated/non-isolated - should I strive for one setup over the other?

I'm undecided at the moment whether I want to keep the DS300 and its control panel, or switch out to something else. At the moment it connects to my awning light, water pump, my water tank level meter and both batteries to show their capacity, and gives an on/off master switch for the house side of things.

I'd happily lose the rubbish battery meters in favour of a proper shunt & display (Renogy 500A?) for the house battery and nothing for the van battery. And I guess the other three functions are easily replaced by a trio of rocker switches.

Any advice hugely appreciated!
 
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(I also have the CBE mains charger coming from the electric hook-up, but I can't see us ever using that, so I'll probably just remove/disable it)
 
Hi,
the starter battery and house, leisure, battery have connon connection to van negative, the vehicle metalwork, the DS 300 has a common negative battery termination. Thus the non isolated Orion is OK to use, there is no adbvantage one over the other electrically. The non isolated is lower cost.
Whilst the Renogy battery monitor is a possible, I recomend Victron Smart Shunt, ( or the Victron BMV 712) as a more reliable and better engineered product.
Having only engine charging and no AC charger seems strange, do you have solar? The battery charger fitted in a CBE system is either a CB500, or CB516, either is OK for lithium with a 14.1 charge and 13.5 float.
As normally installed provide a maintaining charge to the starter battery.

The standard starter battery connections to the DS 300 are to terminal +B1 via a fuse at/near the starter battery,value 50 amps,and a similar fuse at/near the +B1 terminal.

One option in fitting the Orion, is to connect in this path and use the combine relay in the DS 300 to link to the house battery.
Link fuses and holders, Midi fuses, 60 amp, with eye crimped cable terminations should be used with 10mm2 cable.
All CBE functions should work with the exception of AC charger providing a maintaining charge, and starter battery voltage, engine off.

The second option for installing the Orion is to connect the Orion output direct to the house battery, again using 10mm2 cable and 60 amp fuses.
You will lose on the CBE, engine battery voltage and charging, and engine powering of 3 way, (gas) fridge. There is no connection of starter battery to +B1, this terminal is unused.

A third option is to fit a 70 amp rated change over relay connected to +B1. The normally closed input of this relay connects to engine battery, and the normally open input of the relay to the Orion output. The relay is activated by the DS300 D+ signal.
This will give a normal starter battery connection to the DS300 until the engine is started, the relay then switches and the Orion is now in circuit.
All features of the DS are functional.

Option two with a direct connection to the house battery avoids volt drops in relays and connections.. providing you are prepared to lose starter battery chargind/display and fridge functions, its the preferred option.

Feeding the 3 way gas fridge from an additional relay is possible.

Mike
 
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Thanks, I was just reading about battery monitors. Am I right in saying the smart shunt only has a bluetooth interface (no display)? And the BMV 712 has both (and also comes with a shunt - terrible naming of these things on Victron's part if so!)?

Put it another way: I want accurate SoC/load levels both on a display and via bluetooth - what do I need to buy? ?

Thank you mike!

PS I've just checked my DS300 and I'm happy to report I have r37, so other than installing the b2b & shunt/monitor all I need to do is snip that, is that right? I leave both batteries connected to the DS300 as they were before, and my PC100 will continue to function as it did before?
 
I want accurate SoC/load levels both on a display and via bluetooth - what do I need to buy?
If a Victron product, with no other Victron stuff, then a BMV 712.

Note with all battery monitors the SOC is a best guess, at least with the Victron there are parameters you can adjust to get optimum results.



if snip that, R37, will my PC100 will continue to function as it did before?
by doing this you loose the internal combining relay and may lose functions related to the starter battery.

Everything powered from the house battery functions as normal .

Unless you make a connection to the house battery from the engine battery via the battery to battery charger, the house battery will not be charged
 
Hi, the starter battery and house, leisure, battery have connon connection to van negative, the vehicle metalwork, the DS 300 has a common negative battery termination. Thus the non isolated Orion is OK to use, there is no adbvantage one over the other electrically. The non isolated is lower cost.
Great, thank you.

Whilst the Renogy battery monitor is a possible, I recomend Victron Smart Shunt, ( or the Victron BMV 712) as a more reliable and better engineered product.
BMV-712 bought, thanks.

Having only engine charging and no AC charger seems strange, do you have solar? The battery charger fitted in a CBE system is either a CB500, or CB516, either is OK for lithium with a 14.1 charge and 13.5 float.
I'm not looking at it right now, but IIRC ours is a CB-516. I assumed it wouldn't be ok with lithium, but you're sure it will? I have no solar yet, but will be adding it soon. In the 12 months we've owned the camper (converted by someone else) we've never used the electric hook-up, and I don't suspect we ever will, but it's good to know it won't kill the lithium battery if we do!

The second option for installing the Orion is to connect the Orion output direct to the house battery, again using 10mm2 cable and 60 amp fuses.
You will lose on the CBE, engine battery voltage and charging, and engine powering of 3 way, (gas) fridge. There is no connection of starter battery to +B1, this terminal is unused.

Option two with a direct connection to the house battery avoids volt drops in relays and connections.. providing you are prepared to lose starter battery chargind/display and fridge functions, its the preferred option.
Certainly happy with that - I don't feel the need to check the level of the starter battery, and we have no 3-way fridge, just a 12v compressor one.

downhiller: "if snip that, R37, will my PC100 will continue to function as it did before?"

by doing this you loose the internal combining relay and may lose functions related to the starter battery.

Everything powered from the house battery functions as normal .

Unless you make a connection to the house battery from the engine battery via the battery to battery charger, the house battery will not be charged
I'm confused - should I be snipping r37, or just disconnecting the starter battery from the DS300? Or both?

To clarify:
1) I don't care about the starter battery monitor on the PC100
2) I will be using an Orion Tr Smart between the starter battery and the house battery

So do I:
1) disconnect starter battery from DS300.
2) snip r37
3) connect both battery positives directly to the Orion (appropriately fused etc)
4) for the Orion neutral/negative, this should come from the chassis? If that's not convenient where it's installed, is it suitable to take a negative from one/both of the batteries instead?

Does that all sound right?
 
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In addition to the above long tedious post (sorry!) @mikefitz , do you have any recommendations of suitable drop-in replacements if I wanted to strip all the CBE stuff out, something with a more modern control panel, for instance? I've not researched this space at all yet, I've no idea what options are available. I do feel quite spend-happy right now though ?

Thank you SO MUCH for all your help.
 
Disconnect the starter battery from +B1 on the DS 300, don't modify the DS 300.

Connect the Orion to starter and house battery.

The starter and house battery negatives need connection to each other , either with cable or via the vehicle metal. The starter battery is already connected to van metal. Orion negative to either battery negative or to same vehicle metal connection as used by either battery.

If the CBE is connected to stuff, lights, water pump, fridge, and all is working then replacing , whilst not impossible, will be a chore.
You could replace the control panel, get advice from a CBE on compatability


Lithium battery from, (recomend Bluetooth reporting from battery, will allow access to cell volts)

Sterling Power
Roamer Batteries
KS Energy
Personally of the above I would select Roamer.

Mike
 
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Already selected Sterling 300A for that side. Roamer out of stock until August. Not come across KS Energy until now, ah well.

Thank you again Mike.
 
Disconnect the starter battery from +B1 on the DS 300, don't modify the DS 300.

Connect the Orion to starter and house battery.

The starter and house battery negatives need connection to each other , either with cable or via the vehicle metal. The starter battery is already connected to van metal. Orion negative to either battery negative or to same vehicle metal connection as used by either battery.

If the CBE is connected to stuff, lights, water pump, fridge, and all is working then replacing , whilst not impossible, will be a chore.
You could replace the control panel, get advice from a CBE on compatability


Lithium battery from, (recomend Bluetooth reporting from battery, will allow access to cell volts)

Sterling Power
Roamer Batteries
KS Energy
Personally of the above I would select Roamer.

Mike

Hi @mikefitz - finally getting around to this job today.

I have two queries, sorry!!!:

**First:**

You said "Disconnect the starter battery from +B1 on the DS 300, don't modify the DS 300.", when the common advice seems to be to cut R37. Can you explain why for me please?

The manual states this:

"NB: in the case of installation of equipment that needs permanent exclusion of the battery parallel relay you must remove the R37 resistor"

**Second:**

The current set up (PC100 control panel, DS300 distribution box, etc) has (to me) an annoying quirk whereby of the engine is running I can't use the lights or USB/12v sockets in the back.

Is that by design, or is something fishy going on? If it is by design, can it be changed - how?

I'm guessing disconnecting the starter battery from B1 will negate this behaviour anyway...? Hopefully!

THANK YOU!
 
Hi!
I'm new to this forum. Just wanted to say thanks for all the sharing of good information and good question.

I've pretty much the same setup as the previous people. I haven't connected everything yet. But This is how I'm planing to set it all up.

I will simply disconnect the B1+ between DS300 and starter battery and install a dc to dc booster.

If I got everything right from all the previous post the only thing i will be missing is:
-The charging from 240v when on landcharging
-The status indicator on the PC-100 display

The CBE 516 will be set for lead if i undstod everything right.

The reason i'm not moving the MPPT output to the servicebattery is because it was already installed and the cable management inside this vehicle (Knaus BoxLife600 Fiat ducato 2017) is horrible.

Please correct me if you see something wrong.

Cheers!


Schematic.png
 
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