S
Shadrack
Lifetime VIP Member
Hi all,
I have finally completed my Phase 3 to my leisure battery upgrade.
Update as promissed.
Phase 1 was to first fit solar:-
vwcaliforniaclub.com
Phase 2 was to upgrade the split charge relay:-
vwcaliforniaclub.com
Now after a lot of research and help from this and the T6 forum I took the plunge and swapped out my ageing agm’s for a single under seat Lithium from Fogstar.
This battery comes with an inbuilt heater for charging in temperatures less than zero degrees, Also a ten year warranty.
Fogstar after sales have been great with help and information when asked.
I chose the Fogstar 230amp drift, it fits nicely under the drivers seat along with a 200amp fuse and isolation switch.
I ran two heavy duty cables to the passenger seat side in the ducting under the carpets to connect to original battery terminals via two new bus bars.
(I ran two cables rather than just one & earth the neutral under the drivers seat so not to bypass the shunt to maintain correct CP information)
With the newfound space under the passenger seat I added a 1000watt inverter from Renogy. I chose just the 1000w because of physical size and most of my appliances, Air fryer, toaster, kettle, induction hob etc are rated less than this. Also the current drawn from the battery at 1kw is getting on for 80 amps. I would have had to consider even heavier cables if I went to a bigger inverter.
The inverter remote along with a 13amp socket fits neatly behind the passenger seat.
Whilst fitting the bus bars I added a couple of Anderson connectors which connect to the engine agm battery and the leisure battery. I have a victron plugin 30amp charger which I can connect to these if ever needed. This charger does allow me to change the battery profile via Bluetooth should I ever need it.
The Victron solar controller seems to keep the battery topped up pretty well. When this was installed I also added a break before make switch and took a cable to the engine battery. Again via Bluetooth I can change the profile of this between LifePo4 or AGM. This could allow me to top the engine battery via solar should it ever be needed.
The split charge relay replacement was the Victron 30amp smart dc to dc Charger. This can be controlled via Bluetooth. Currently I have switched it off and keep the lithium topped up with solar only. I guess with no leisure load on the alternator I maybe get a better mpg? I can switch this back on for up to 30amp charge whilst engine is running.
Another bonus is I have a spare compartment in the rear now where a leisure battery was installed. I will remove the now redundant factory fitted hookup Charger as the profile Is AGM only.
This added space will be used as a new tool store freeing up space under my rear seat. Also I am carrying 25-30Kg less in weight.

This is the battery underneath drivers seat before finally connecting:-

Under Passengers seat the two bus bars and also the Inverter with Anderson connectors on top.

The Inverter control panel and 13amp socket.

Fogstar app showing battery levels whilst boiling a kettle. (Note current being drawn)
A kettle of 1ltr took 5-6amps out of the battery to boil.
For me to even take on these phases or projects would not have happened if it was not for the people on this forum and neighbouring T6 forum. I can’t thank the help from all the posters enough for such a great knowledge base.
Really big thank you to everyone.
I have finally completed my Phase 3 to my leisure battery upgrade.
Update as promissed.
Phase 1 was to first fit solar:-

Solar connection
Hi to all, I am about to instal a Victron MPPT 75/15 in readiness after I fit a couple of permanent 100w panels To my 2016 204. I have read and looked at many installations and diagrams, some wired a little different to others. I plan to put an isolation trip between the panels and Victron. I...

Phase 2 was to upgrade the split charge relay:-

Ocean Lifepo4 Victron 100ah X 2
Has anyone tried to replace the two original service batteries (dimension 315x190x175) with the victron 100ah lifepo4 (dimensions 321x197x152 )? https://www.victronenergy.it/upload/documents/Datasheet-12,8-&-25,6-Volt-lithium-iron-phosphate-batteries-Smart-IT.pdf it seems that there are 6 mm...

Now after a lot of research and help from this and the T6 forum I took the plunge and swapped out my ageing agm’s for a single under seat Lithium from Fogstar.
This battery comes with an inbuilt heater for charging in temperatures less than zero degrees, Also a ten year warranty.
Fogstar after sales have been great with help and information when asked.
I chose the Fogstar 230amp drift, it fits nicely under the drivers seat along with a 200amp fuse and isolation switch.
I ran two heavy duty cables to the passenger seat side in the ducting under the carpets to connect to original battery terminals via two new bus bars.
(I ran two cables rather than just one & earth the neutral under the drivers seat so not to bypass the shunt to maintain correct CP information)
With the newfound space under the passenger seat I added a 1000watt inverter from Renogy. I chose just the 1000w because of physical size and most of my appliances, Air fryer, toaster, kettle, induction hob etc are rated less than this. Also the current drawn from the battery at 1kw is getting on for 80 amps. I would have had to consider even heavier cables if I went to a bigger inverter.
The inverter remote along with a 13amp socket fits neatly behind the passenger seat.
Whilst fitting the bus bars I added a couple of Anderson connectors which connect to the engine agm battery and the leisure battery. I have a victron plugin 30amp charger which I can connect to these if ever needed. This charger does allow me to change the battery profile via Bluetooth should I ever need it.
The Victron solar controller seems to keep the battery topped up pretty well. When this was installed I also added a break before make switch and took a cable to the engine battery. Again via Bluetooth I can change the profile of this between LifePo4 or AGM. This could allow me to top the engine battery via solar should it ever be needed.
The split charge relay replacement was the Victron 30amp smart dc to dc Charger. This can be controlled via Bluetooth. Currently I have switched it off and keep the lithium topped up with solar only. I guess with no leisure load on the alternator I maybe get a better mpg? I can switch this back on for up to 30amp charge whilst engine is running.
Another bonus is I have a spare compartment in the rear now where a leisure battery was installed. I will remove the now redundant factory fitted hookup Charger as the profile Is AGM only.
This added space will be used as a new tool store freeing up space under my rear seat. Also I am carrying 25-30Kg less in weight.

This is the battery underneath drivers seat before finally connecting:-

Under Passengers seat the two bus bars and also the Inverter with Anderson connectors on top.

The Inverter control panel and 13amp socket.

Fogstar app showing battery levels whilst boiling a kettle. (Note current being drawn)
A kettle of 1ltr took 5-6amps out of the battery to boil.
For me to even take on these phases or projects would not have happened if it was not for the people on this forum and neighbouring T6 forum. I can’t thank the help from all the posters enough for such a great knowledge base.
Really big thank you to everyone.
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