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Leisure Battery
- Thread starter Ian M
- Start date
Van Diesel
Active Member
Well am still waiting for them
To be availableSounds really appealing. My thoughts where to put the dc to dc there to avoid pulling to much current from the generator.
some inspiration.. D a 150 ah is enough i think.-....since you have to drive along time reacharging a 180ah. however these batteries are not as good as titans,,,they will do i think. D
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Soon a 260ah lithium in the same size: https://titanlithium.co.uk/products/titan-12v-260ah-lithium-battery-type-019-din
Van Diesel
Active Member
top dollar lol. D just remember the land current charger is under the fridge...and without a dc-dc... you will lack power since mercedes charge algorithm is wierd.. D u can watch the charge in the menu mbux. D it will 80-100 when low....which is out of recommended charge spec.... maybe thats not to bad, but worse is that it will charge almost nothing when above 80%. making a 260ah really need better controlling i think. D im not exactly sure about the capabillities of the ground current charger.... but you can find it and see for your self easy under the fridge.. just remove the panel... and the wire to seat. D
again a tech dude is needed since this ground charger also charges the main starter battery. which you cant replace with these ones ..
you realizing a project i had for some time.... let me know how it goes D GL
again a tech dude is needed since this ground charger also charges the main starter battery. which you cant replace with these ones ..
you realizing a project i had for some time.... let me know how it goes D GL
Van Diesel
Active Member
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everything you need to know. D
Kevin John
Member
Hello all. I'm in the process of installing a Victron Orion XS 12/12-50 in my 2021 MP. I plan to keep the 2023 AGM until it wears out. I'll then replace it with a LiPo. The Orion XS will have no problem with the new chemistry but the shore power charger is rather primitive. Has anyone found a good replacement for the Dometic ? It looks like Victron IP22 might work. Anyone try it? Best, KJ
Kevin John
Member
I'll have to get back on board and measure. It looks like a very tight fit for where the existing Dometic is but there might be just enough room for the Victron IP22. At any rate, as I'm keeping the existing AGM, I'm not in a big hurry to change out chargers.
I'll try to post some photos of my Orion XS install. My idea is to replace the K120 relay with it and add a Smartshunt 500A for monitoring. It's VERY tight but I think I'll be able to shoehorn it in once I get the right cable and crimp ends.
Did you get around to this. Would love some inputs on location of the victron Orion xs dc - dc
Bobtheknob
Member
Does anyone have a schematic for the charge system? My 2024 has charging issues since Mercedes fixed the heating and they are completely useless and have no idea what they are doing.
Kevin John
Member
Yes. My MP is left hand drive and the service battery is under that seat. As the Orion XS is much smaller than the previous model, I was able to shoehorn it into the space where the K120 relay was. It is easily identifiable as it has As you may or may no know, the K120 is a voltage sensitive relay that joins the start and service batteies together when a charging voltage is present. With Euro6 alternators, they shut off after a few minutes once your engine is running. This reduces the load on the engine and associated emmissions. As everyone knows, this doesn't do us a lot of help in charging the service battery. I was obligated to unmount a component inboard of the K120 to make room for the Orion XS and used zip ties to secure it in place. I mounted the Orion XS to the existing panel where the K120 was with two of the 4 available screw holes. I'm confident it will hold. I also installed a Victron SmartShunt to monitor the service battery charge conidition as this installation throws off the onboard computer's monitoring of the service battery. The shunt was a bit of a challenge due to limited space available but it's held in place via pressure from the access panel and the stiffness of the cables (16mm2).
In preparation for a lifepo4 install, I pulled a cable between the two seats so I can add a Votronic Standby Charger Pro for shore power charging the two different chemistries. I plan to pull the second sensing wire for the SmartShunt to monitor the start battery once I start the lifepo4 install.
For shore power charging, I bought a Victron Blue Smart IP22 220v charger. The available space under the reefer is also quite limited and I'll eventually have to modify the bracket that holds the plug for the reclining rear seats to accommodate it. It won't be pretty but I only need about 7mm.
Side bar: It's important to use the correct size wiring as there is the capacity for high amps while charging. I had some extra 6AWG (16mm2) cabling to use to complete this stage of the project.
Side bar 2: The K120 has crimp eye connectors and the IP22 uses crimp on ferrules. I'll be honest and tell you that it took a little courage to cut those crimp eyes off because that was the point of no return. All worked out well and I used Gemini AI to program the Orion XS while driving to Cherbourg to meet a client. So far it is working like a champ but we haven't done a deep discharge cycle on the service battery since installation. We'll get around to that later next week.
Side bar 3: I detuned the Orion XS to 15a max output (capable of 30a) as the space it is installed is quite tight and I don't want it getting too hot in there. I'll monitor the heat with an infrared temp gun and tune it up or down.
Due to limited time and fatigue, I didn't document the installation with any photos but I'll take a stab at that when, if, I get around to the lifepo4. Presently looking at a Titan 150ah unit (that has been talked about on this forum. It is much more that we'll need for the demands of our 2021 MP but will give us much longer off-grid autonomy. We do not need an an inverter as most of our needs are satisfied by the USB outlets and I don't know where it would go if we wanted one.
FWIW, I have a background in marine (yachts) systems installation so I wasn't/am not too daunted by the prospect of these modifications. In the spirit of full disclosure, I used Gemini AI extensively on this install to have added confidence. It's important to have a background in these types of installation to know whether or not you are getting good answers. Gemini proved much better than Claude.
Finally, I ordered the Votronic Stand By Charger Pro from a company in Berlin named Stromzone. The price was too good to be true and it seems I've been scammed. Be advised.
Here's photo of the K120. I had to fab a ground wire to attach the Orion XS to the van's ground (small gauge brown wires in the photo). The sensing wires on the K120 are not used.
Thank you for this precise description. Mine is also left hand drive If I understand it right, the k120 is under the other seat then the leasure batteri ? Was it obvious which cables is in and out - and did you reuse those. I am thinking to replace only the k120 with the Orion xs and keep the build in dometic charger for charging from the grid - would that work, you think?
I just don’t quite understand how the build in dometic charger can charge til start batteri as well. It says so in the manual that it does. But then also as you are thinking replace the leasure battery with titan, as it accepts an agm profile for charging. The titan seems to also have a Bluetooth connection to understand the current charge situation
Kevin John
Member
Hi Torben. The cable from the K120 to the service (leisure) battery was led direcly to it and easiliy identified. As they were in the same compartment (under the left seat) it wasn't complcated. I reused the existing cables but had to cut off the eye ends and replace them with crimp on ferrules. That was the point of no return I mentioned above. I also had to fabricate a 16mm2 ground cable for the Orion XS that is also 16mm2. This required a heavy duty (large cable) crimp tool, which I already had. I used the same crimp tool to fabricate the cables required to install the SmartShunt.
Last August I checked the start battery voltage while plugged into shore power. It did have charging voltage at the terminals under the hood where you would jump start the engine if the battery ran too low to crank the engine. Given what you've said about the location of your service battery, and what I've found online, I don't think Westfalia configures each van identically. You'll definitely want to confirm which side of your van has the start battery and service battery.
As for the charging profile for a lifepo4 battery, it is different than that of an AGM and for the sake of expensive battery longevity, I'll replace the Dometic charger with the Victron Blue Smart IP22 and install an echo charger of some sort for the start battery. This will be followed by another long post, hopefully with photos. One of the main obastacle of installing the IP22 is it will require larger gauge cables that are currently in place. I won't be able to use the smaller existing cables (in parallel) as I'm not sure if their lengths are identical, which is necessary if using the pair. The shorter of the two will be overloaded as there is less resistance/voltage drop and the shorter one would be overloaded. Pulling cable on an MP is not easy and would be the first thing I'd tackle before installing the IP22. If I am unable to do it to my satifaction, I'll just stick with AGM chemistry for the service battery and be happy that I get good charging current with the Orion XS while driving.
FYI, the bluetooth connectivity on the Titan has nothing to do with the charging profile. The Dometic charger on my van is dumb and only good for AGMs. The model on my van is an SMP439-02.
Side bar: I'm still glad to have purchased the IP22 in advance as I have 5x 140ah Exide Dual AGMs that I aquired from a new boat that was upgrading to lifepo4s. They had sat in my garage for 5y and the smart charger brought them all back to like new condition. If/when I sell them, I'll use the proceeds to buy the Titan 150ah beast.
Here's another photo from early in the project.
View attachment 4298CF03-4542-4B16-9DFA-3AAC80E9F52B_1_201_a.jpeg
Last August I checked the start battery voltage while plugged into shore power. It did have charging voltage at the terminals under the hood where you would jump start the engine if the battery ran too low to crank the engine. Given what you've said about the location of your service battery, and what I've found online, I don't think Westfalia configures each van identically. You'll definitely want to confirm which side of your van has the start battery and service battery.
As for the charging profile for a lifepo4 battery, it is different than that of an AGM and for the sake of expensive battery longevity, I'll replace the Dometic charger with the Victron Blue Smart IP22 and install an echo charger of some sort for the start battery. This will be followed by another long post, hopefully with photos. One of the main obastacle of installing the IP22 is it will require larger gauge cables that are currently in place. I won't be able to use the smaller existing cables (in parallel) as I'm not sure if their lengths are identical, which is necessary if using the pair. The shorter of the two will be overloaded as there is less resistance/voltage drop and the shorter one would be overloaded. Pulling cable on an MP is not easy and would be the first thing I'd tackle before installing the IP22. If I am unable to do it to my satifaction, I'll just stick with AGM chemistry for the service battery and be happy that I get good charging current with the Orion XS while driving.
FYI, the bluetooth connectivity on the Titan has nothing to do with the charging profile. The Dometic charger on my van is dumb and only good for AGMs. The model on my van is an SMP439-02.
Side bar: I'm still glad to have purchased the IP22 in advance as I have 5x 140ah Exide Dual AGMs that I aquired from a new boat that was upgrading to lifepo4s. They had sat in my garage for 5y and the smart charger brought them all back to like new condition. If/when I sell them, I'll use the proceeds to buy the Titan 150ah beast.
Here's another photo from early in the project.
View attachment 4298CF03-4542-4B16-9DFA-3AAC80E9F52B_1_201_a.jpeg
This is great. Thank you so much. I now have the confidence to do this. I did work with electronic systems and low voltage many many years ago, but at least i understand the basics still. I do not have the crimp tool nor the ferrules. but thats just a good option to buy new stuff What i missed i think was that the K120 was also in the same compartment as the leasure battery.... I will look better next time, only thing i saw yeaterday was a dunlop something. I thought the K120 was on the right side with the starter batteri??
Doeas yours also have the heater installed for the living compartment on the left side, under the seat as well??
I did yesterday remove the batteri on the left site looking out the front window (the drivers site in Denmark, and passengers site in UK normally ) and that rendered the camper display to turn off. But the ignition was still possible. So the camper or leasure batteri is in the left side on my car.
I get that the bluetooth on the titan has nothing to do with charging profile, but I would use it to keep track of the "load" left when the onboard display will propably stop indicating correct. I would to change the onboard charger, but is hoping to be able to this in steps, in order not to overload myself. I did read somewhere though that the titan could utilize an AGM charging profile because their BMS was build to handle this as well.
Again thanks a lot...
What i missed i think was that the K120 was also in the same compartment as the leasure battery.... I will look better next time, only thing i saw yeaterday was a dunlop something. I thought the K120 was on the right side with the starter batteri?? Doeas yours also have the heater installed for the living compartment on the left side, under the seat as well??
I did yesterday remove the batteri on the left site looking out the front window (the drivers site in Denmark, and passengers site in UK normally
) and that rendered the camper display to turn off. But the ignition was still possible. So the camper or leasure batteri is in the left side on my car. I get that the bluetooth on the titan has nothing to do with charging profile, but I would use it to keep track of the "load" left when the onboard display will propably stop indicating correct. I would to change the onboard charger, but is hoping to be able to this in steps, in order not to overload myself. I did read somewhere though that the titan could utilize an AGM charging profile because their BMS was build to handle this as well.
Again thanks a lot...
Kevin John
Member
Your indication of the K120 is the heavy gauge wires led to it.
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