310W permanent solar on a 22MY T6.1 Ocean

[Oceanis]

Found these ...

VANVOLT LiFePO4 Lithium Batterie 12,8V 100Ah DIN H6 Arctic BMS mit Bl, 729,00 €

Top-Qualität nach europäischen Standards Wir als Hersteller im Sinne des Gesetzes übernehmen die Garantie dafür, dass dieses Produkt bei sachgemäßer Verwend

big-difference.com

Lithium LiFePO4 Caravan VW T6 12V / 100Ah | CS-Batteries

Lithium LiFePO4 Caravan / Wohnmobil VW T6 Untersitz-Batterie 12V / 100Ah ✔ große Auswahl ✔ bester Preis ✔ schnelle Lieferung ➤ sicher bei uns bestel

cs-batteries.de

12,8V Lithium 100Ah LiFePO4 Premium Batterie | 200A-BMS-2.0 | Ducato

12,8V Lithium 100Ah LiFePO4 Premium Batterie | 200A-BMS-2.0 | Ducato Ford PSA VWT6 TGE | 1280Wh | IP67 in PREMIUM-VERSORGUNGS-BATTERIEN, PRODUKTE

www.forster-batteries.de

Basically drop in batteries that fit the same space as the AGMs currently in my T6.1

So ... been toying with fitting LiFePO4 batteries for a while, but obviously from the factory it is set up with 2 x 75Ah AGM leisure batteries and a VW charger and smart alternator, also set up for AGM batteries. There are shunts on all the batteries and the camper unit monitors how full they are (obviously knowing they are 75Ah AGM batteries) ... so bit of a headache to integrate into the VW system and replace the AGMs with Lithiums .... but I think I have a solution and would be grateful for any observations or mistakes in the following diagram. Everything to the left of the blue dotted line is VW original and the right are my additions.



When parked, the solar will charge both the Lithiums and the AGM starter. (Starter Trickle Switch set to "On")
When on Shore Power, the VW charger will charge the AGM starter because when the charger runs, it closes the isolation relay. The VW charger will also charge the Lithiums via the DC-DC (Starter Trickle Switch can be "Off or "On" but will have no effect)
When engine is running, the DC-DC and the MPPT will charge the Lithium batteries. (Starter Trickle Switch best set to "Off", On will fight the smart alternator, but I have this at the moment and it has no discernable effect other than producing a much bigger solar yield.)

The position of the switch isn't critical and the battery protect will protect the lithium batteries from discharging when there is not a charging source present.

That is my thinking ... anyone notice any glaring errors?

Will take the plunge this summer and see how the Camper Unit copes with this setup and how it reports the battery status. If it is too confused then I will put in Victron shunts and monitor the leisure batteries with a battery monitor.

Future projects are a CerboGX OS running on a Raspberry Pi, and an Inverter upgrade.

 

[Californication69]

Found these ...

VANVOLT LiFePO4 Lithium Batterie 12,8V 100Ah DIN H6 Arctic BMS mit Bl, 729,00 €

Top-Qualität nach europäischen Standards Wir als Hersteller im Sinne des Gesetzes übernehmen die Garantie dafür, dass dieses Produkt bei sachgemäßer Verwend

big-difference.com

Lithium LiFePO4 Caravan VW T6 12V / 100Ah | CS-Batteries

Lithium LiFePO4 Caravan / Wohnmobil VW T6 Untersitz-Batterie 12V / 100Ah ✔ große Auswahl ✔ bester Preis ✔ schnelle Lieferung ➤ sicher bei uns bestel

cs-batteries.de

12,8V Lithium 100Ah LiFePO4 Premium Batterie | 200A-BMS-2.0 | Ducato

12,8V Lithium 100Ah LiFePO4 Premium Batterie | 200A-BMS-2.0 | Ducato Ford PSA VWT6 TGE | 1280Wh | IP67 in PREMIUM-VERSORGUNGS-BATTERIEN, PRODUKTE

www.forster-batteries.de

Basically drop in batteries that fit the same space as the AGMs currently in my T6.1

So ... been toying with fitting LiFePO4 batteries for a while, but obviously from the factory it is set up with 2 x 75Ah AGM leisure batteries and a VW charger and smart alternator, also set up for AGM batteries. There are shunts on all the batteries and the camper unit monitors how full they are (obviously knowing they are 75Ah AGM batteries) ... so bit of a headache to integrate into the VW system and replace the AGMs with Lithiums .... but I think I have a solution and would be grateful for any observations or mistakes in the following diagram. Everything to the left of the blue dotted line is VW original and the right are my additions.

View attachment 200576

When parked, the solar will charge both the Lithiums and the AGM starter. (Starter Trickle Switch set to "On")
When on Shore Power, the VW charger will charge the AGM starter because when the charger runs, it closes the isolation relay. The VW charger will also charge the Lithiums via the DC-DC (Starter Trickle Switch can be "Off or "On" but will have no effect)
When engine is running, the DC-DC and the MPPT will charge the Lithium batteries. (Starter Trickle Switch best set to "Off", On will fight the smart alternator, but I have this at the moment and it has no discernable effect other than producing a much bigger solar yield.)

The position of the switch isn't critical and the battery protect will protect the lithium batteries from discharging when there is not a charging source present.

That is my thinking ... anyone notice any glaring errors?

Will take the plunge this summer and see how the Camper Unit copes with this setup and how it reports the battery status. If it is too confused then I will put in Victron shunts and monitor the leisure batteries with a battery monitor.

Future projects are a CerboGX OS running on a Raspberry Pi, and an Inverter upgrade.

Why didn’t you use an Epever Duo Racer MPPT?
You can use a single 1.5mm cable direct to the relay for charging the starter motor.
It connects to BATT2 connector on the EPever terminals.

Can you explain parallel and series to me like I’m 5 aha. !
So if I bought two 120w panels, which is the best way for UK weather to charge the two (Lesuire batteries that are connected together, forming one 150a battery)

 

[Oceanis]

Why didn’t you use an Epever Duo Racer MPPT?
You can use a single 1.5mm cable direct to the relay for charging the starter motor.
It connects to BATT2 connector on the EPever terminals.

Can you explain parallel and series to me like I’m 5 aha. !
So if I bought two 120w panels, which is the best way for UK weather to charge the two (Lesuire batteries that are connected together, forming one 150a battery)

I could have done that ... but I didn't. Bit of a Victron fan and the camper van is being used as a test bed for the next boat. Just managed to install the Victron Venus OS on a Raspberry Pi which is quite impressive with it's internet portal for remote monitoring.

Panels in parallel or series? ... depends if the shading is predictable and consistent. If it is just random, like clouds, then it makes no discernable difference. I proved that to myself on the last boat with a few week long experiments to determine the daily yield in each configuration. There was no difference. Parallel is definitely the way to go if the panels are fixed and there is a shadow cast on them regularly as the sun traverses the sky - with the assumption that it is a reasonably cheap panel with no bypass circuitry to bypass a shaded (or damaged) panel when wired in series.

As for the amps and volts stuff ... try this YouTube Video.

 

[Californication69]

I’ve decided to wire them up in Series, as using an original curly cable into the rear tailgate Wallace.
So the higher voltage will give for a longer charge when in series.
Once you’ve tested a panel and it’s worked well for 3 months, should last a good couple to 7
Found a great info graphic.
Show’s why Series is better for UK weather all year round.

 

[Dellmassive]

Nice graphic.

It shows the charge window of series Vs parallel nicely.

....

Assuming both panels are together to Avoid any partial shading.

 

[Grim Reaper]

One or two things I have noticed on this thread.. In your first post you said Victron suggested their 20A charger, I suspect this was because your original plan was to use AGM batteries, Victron have been correct in limiting the charge current to AGM's as they don't take well to high current charging.
Second, I think you've ended up with a far too complicated system, You appear to have ended up using Lithium Leisure batteries, and these will take much higher charge currents so I would have (and indeed have) gone with a Redarc 40A charger (a 50A version is now available) that can handle the smart alternator and solar inputs and a small victron solar charge controller to allow switching of the solar input to charge the starter battery when needed as the charge profile is different from Lithium Leisure to AGM Starter (similar to what you have ended up with)
Third, I don't see an inverter in any of your diagrams, I assume the Ocean has 240V outlets, can the VW inverter be switched off?
Granted the Redarc is limited by voltage on the solar input but I'm not seeing any issues with the leisure batteries running flat in use, the 200W panel I have is plenty to replace what gets used overnight from my 100Ah lithium leisure battery. I have yet to use my inverter for anything on a trip, so many things can be USB or 12V versions nowadays, and the inverter will be the most drain on the system, if it gets left on, it's a battery killer.

 

[Californication69]

I’ve decided to wire them up in Series, as using an original curly cable into the rear tailgate Wallace.
So the higher voltage will give for a longer charge when in series.
Once you’ve tested a panel and it’s worked well for 3 months, should last a good couple to 7
Found a great info graphic.
Show’s why Series is better for UK weather all year round.
View attachment 203524

That’s what I was thinking, even if one panel had a slight shade, might pull down to 20 volts, but then you’d still be charging let’s say’s at 20v and 3amps in series, rather than at 10v and 6 amps if I was in parallel.

 

[Californication69]

Bit the bullet, and got

1 x 20A Victron SmartSolar MPPT100-20 - 100Voc, PV Solar Charge Controller - 12V, 24V, 48V Battery
1 x Victron Orion 12v to 12v 9A 110W DC-DC converter isolated 12--12-9A (110W)
1 x Victron VE Direct to USB interface
1 x Europa Single String DC Switch Disconnector 16A 4 Pole Enclosed

Glad I have a PV disconnector.
The VE Direct to a RPi running Venus.

One thing I found. Had to use wife’s iPhone running iOS 16, rather than mine using Beta iOS17 to update the Bluetooth on the Victron kit.
Can’t update BT via RPi.

Pi-4 2GB with 32gb SD runs Venus really nicely.

One question I have.
Have you got a Victron 500a shunt on the negative on Lesuire battery.
As I want to run a cable from the shunt to the starter motor relay to measure starter.