Dual battery setup modifications

tristand · Oct 12, 2023

Hi All,

I have the factory dual battery setup and decided to make a few changes to the vehicle wiring to make it more useful. I wanted to have the following:

Front and rear 12V outlets powered from second battery
Rear USB outpets powered from second battery
All aux power supplies (under bonnet, roof and footwell) powered from second battery
Rear high power output (NATO socket) powered from second battery and switchable whenever needed (no neutral interlock etc.)
Winch (transmission) still protected by existing interlocks
Aux fusebox for additional 12V loads on second battery
Battery monitoring on second battery
Allow for high current supply to inverter from seconf battery

It was actually pretty simple even without a wiring diagram - although this sort of thing is pretty related to the day job.

I rewired the second (5 way) high current fuse box to be powered from the second battery instead of the main battery - this moved the power supply for the NATO socket and grey aux relay / fuse box to the second battery.
I rewired to input to the CTEK unit to come from the main (7 way) high current fuse box.
I added a small aux fuse box powered from the 5 way high current fuse box.
I rewired the power supply to the RI03 relay so that it comes from my new aux fuse box instead of from FI04 - this is the red wire going into the interior electrical centre fuse box wher a fuse used to go. This powers the front and rear 12V outlets, read USB outlets, front footwell outlets and EXT1 under bonnet outlet and the lights in the aux switches of the roof console.
I cut the wire from the EXT5 relay output under the grey fuse / relay box and wired it directly to the positive coil connection of the Albright relay - the NATO socket is now under control of the EXT5 switch. I need to replace the fuse on this with a 5A one.
I added a Victron Smart Shunt battery monitor to the ground line from the second battery - I can now precicely monitor its state of charge.
I removed the 300A single fuse between CTEK output and second battery and used a 300A Z Case fuse in the 5 way high current fuse box instead.
I added additional lighting in the rear load space and am output for a fridge from the new aux fuse box.
I also got rid of the top panels of the under seat electrical enclosure and secured the front panesls with cable ties - the whole under seat enclosure is a crap design which would get any of my engineers fired.

Tristan

Tazzieman · Oct 12, 2023

Very nice!
(but I do hate exposed live terminals!)

Clark Kent · Oct 12, 2023

tristand said:
Hi All,

I have the factory dual battery setup and decided to make a few changes to the vehicle wiring to make it more useful. I wanted to have the following:

Front and rear 12V outlets powered from second battery

Rear USB outpets powered from second battery

All aux power supplies (under bonnet, roof and footwell) powered from second battery

Rear high power output (NATO socket) powered from second battery and switchable whenever needed (no neutral interlock etc.)

Winch (transmission) still protected by existing interlocks

Aux fusebox for additional 12V loads on second battery

Battery monitoring on second battery

Allow for high current supply to inverter from seconf battery

It was actually pretty simple even without a wiring diagram - although this sort of thing is pretty related to the day job.

I rewired the second (5 way) high current fuse box to be powered from the second battery instead of the main battery - this moved the power supply for the NATO socket and grey aux relay / fuse box to the second battery.
I rewired to input to the CTEK unit to come from the main (7 way) high current fuse box.
I added a small aux fuse box powered from the 5 way high current fuse box.
I rewired the power supply to the RI03 relay so that it comes from my new aux fuse box instead of from FI04 - this is the red wire going into the interior electrical centre fuse box wher a fuse used to go. This powers the front and rear 12V outlets, read USB outlets, front footwell outlets and EXT1 under bonnet outlet and the lights in the aux switches of the roof console.
I cut the wire from the EXT5 relay output under the grey fuse / relay box and wired it directly to the positive coil connection of the Albright relay - the NATO socket is now under control of the EXT5 switch. I need to replace the fuse on this with a 5A one.
I added a Victron Smart Shunt battery monitor to the ground line from the second battery - I can now precicely monitor its state of charge.
I removed the 300A single fuse between CTEK output and second battery and used a 300A Z Case fuse in the 5 way high current fuse box instead.
I added additional lighting in the rear load space and am output for a fridge from the new aux fuse box.
I also got rid of the top panels of the under seat electrical enclosure and secured the front panesls with cable ties - the whole under seat enclosure is a crap design which would get any of my engineers fired.

View attachment 7829456
View attachment 7829457
View attachment 7829458

Tristan

Classic underachiever. What did you do after lunch?

Looks good. Thank you for taking the time to label and share your pics. I plan to do the same with the enclosure panels. No way those top panels are going back into my vehicle to fight with each time I want to do some work under the seat.

OGrid · Oct 12, 2023

Excellent. Well done and thanks for posting.

Although I’m yet to receive my vehicle I’d started becoming concerned with the factory aux battery setup. This helps greatly, when…not if, I do something similar.

DenisM · Oct 12, 2023

Thank you very much @tristand

... a truly professional approach to achieve how most expect it should have been done in the first place!

Wile E Coyote · Oct 12, 2023

tristand said:
Hi All,

I have the factory dual battery setup and decided to make a few changes to the vehicle wiring to make it more useful. I wanted to have the following:

Front and rear 12V outlets powered from second battery

Rear USB outpets powered from second battery

All aux power supplies (under bonnet, roof and footwell) powered from second battery

Rear high power output (NATO socket) powered from second battery and switchable whenever needed (no neutral interlock etc.)

Winch (transmission) still protected by existing interlocks

Aux fusebox for additional 12V loads on second battery

Battery monitoring on second battery

Allow for high current supply to inverter from seconf battery

It was actually pretty simple even without a wiring diagram - although this sort of thing is pretty related to the day job.

I rewired the second (5 way) high current fuse box to be powered from the second battery instead of the main battery - this moved the power supply for the NATO socket and grey aux relay / fuse box to the second battery.
I rewired to input to the CTEK unit to come from the main (7 way) high current fuse box.
I added a small aux fuse box powered from the 5 way high current fuse box.
I rewired the power supply to the RI03 relay so that it comes from my new aux fuse box instead of from FI04 - this is the red wire going into the interior electrical centre fuse box wher a fuse used to go. This powers the front and rear 12V outlets, read USB outlets, front footwell outlets and EXT1 under bonnet outlet and the lights in the aux switches of the roof console.
I cut the wire from the EXT5 relay output under the grey fuse / relay box and wired it directly to the positive coil connection of the Albright relay - the NATO socket is now under control of the EXT5 switch. I need to replace the fuse on this with a 5A one.
I added a Victron Smart Shunt battery monitor to the ground line from the second battery - I can now precicely monitor its state of charge.
I removed the 300A single fuse between CTEK output and second battery and used a 300A Z Case fuse in the 5 way high current fuse box instead.
I added additional lighting in the rear load space and am output for a fridge from the new aux fuse box.
I also got rid of the top panels of the under seat electrical enclosure and secured the front panesls with cable ties - the whole under seat enclosure is a crap design which would get any of my engineers fired.

View attachment 7829456
View attachment 7829457
View attachment 7829458

Tristan

Awesome! I need to bookmark this post for future reference.
I see you have a spare connection for an inverter, do you also plan to add solar at any stage?

Mr. Largo WINCH · Oct 12, 2023

tristand said:
Hi All,

I have the factory dual battery setup and decided to make a few changes to the vehicle wiring to make it more useful. I wanted to have the following:

Front and rear 12V outlets powered from second battery

Rear USB outpets powered from second battery

All aux power supplies (under bonnet, roof and footwell) powered from second battery

Rear high power output (NATO socket) powered from second battery and switchable whenever needed (no neutral interlock etc.)

Winch (transmission) still protected by existing interlocks

Aux fusebox for additional 12V loads on second battery

Battery monitoring on second battery

Allow for high current supply to inverter from seconf battery

It was actually pretty simple even without a wiring diagram - although this sort of thing is pretty related to the day job.

I rewired the second (5 way) high current fuse box to be powered from the second battery instead of the main battery - this moved the power supply for the NATO socket and grey aux relay / fuse box to the second battery.
I rewired to input to the CTEK unit to come from the main (7 way) high current fuse box.
I added a small aux fuse box powered from the 5 way high current fuse box.
I rewired the power supply to the RI03 relay so that it comes from my new aux fuse box instead of from FI04 - this is the red wire going into the interior electrical centre fuse box wher a fuse used to go. This powers the front and rear 12V outlets, read USB outlets, front footwell outlets and EXT1 under bonnet outlet and the lights in the aux switches of the roof console.
I cut the wire from the EXT5 relay output under the grey fuse / relay box and wired it directly to the positive coil connection of the Albright relay - the NATO socket is now under control of the EXT5 switch. I need to replace the fuse on this with a 5A one.
I added a Victron Smart Shunt battery monitor to the ground line from the second battery - I can now precicely monitor its state of charge.
J'ai retiré le fusible unique de 300 A entre la sortie CTEK et la deuxième batterie et j'ai utilisé à la place un fusible Z Case de 300 A dans la boîte à fusibles à 5 voies à courant élevé.
J'ai ajouté un éclairage supplémentaire dans l'espace de chargement arrière et je suis sorti pour un réfrigérateur à partir de la nouvelle boîte à fusibles auxiliaire.
Je me suis également débarrassé des panneaux supérieurs du boîtier électrique sous le siège et j'ai fixé les panneaux avant avec des serre-câbles - l'ensemble du boîtier sous le siège est d'une conception merdique qui ferait virer n'importe lequel de mes ingénieurs.

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View attachment 7829458

Tristan

anand · Oct 12, 2023

Glad to see someone take the time to do this, nicely done!

Xrford · Oct 12, 2023

@tristand did you connect the 12v ignition on wire on the ctek smart pass? If not I would think the scenario where your auxiliary battery was down on charge but your starter was fully charged, would cause the smart alternator to not turn on and your aux battery will not get charged. The inherent out of the box factory configuration is relying on the starter battery always being in a lesser state of charge than the aux battery so the 12v trigger was not require. I suspect your changes have altered those dynamics, which would necessitate this now being connected. I would be interested in what you smart shunt shows is happening under the aforementioned conditions.

tristand · Oct 13, 2023

Wile E Coyote said:
Awesome! I need to bookmark this post for future reference.
I see you have a spare connection for an inverter, do you also plan to add solar at any stage?

No plans for solar - I'm generally not in the same place for long enough without mains power / alternator charging to need it.

tristand · Oct 13, 2023

Xrford said:
@tristand did you connect the 12v ignition on wire on the ctek smart pass? If not I would think the scenario where your auxiliary battery was down on charge but your starter was fully charged, would cause the smart alternator to not turn on and your aux battery will not get charged. The inherent out of the box factory configuration is relying on the starter battery always being in a lesser state of charge than the aux battery so the 12v trigger was not require. I suspect your changes have altered those dynamics, which would necessitate this now being connected. I would be interested in what you smart shunt shows is happening under the aforementioned conditions.

I've never seen the starter battery charged to the point where the alternator stops charging - I think that when the voltage on the starter battery gets pulled by the alternator after engine start, the CTEK unit links the two batteries so they are efffectively in parallel. If the second battery is low on charge it pulls the voltage of the starter battery down enough that the alternator keeps supplying current to keep the two batteries in parallel charging. After switch off, the CTEK unit keeps them linked until the voltage drops off and you see the second battery supplying current to keep the vehicle systems (wired from the starter battery) powered up for a few minutes.

I'll keep an eye on it.

Lars · Oct 13, 2023

Any way you could create and post a wiring diagram for those of us less mechanically acomplished than you?

bnebenda · Nov 3, 2023

tristand said:
Hi All,

I have the factory dual battery setup and decided to make a few changes to the vehicle wiring to make it more useful. I wanted to have the following:

Front and rear 12V outlets powered from second battery

Rear USB outpets powered from second battery

All aux power supplies (under bonnet, roof and footwell) powered from second battery

Rear high power output (NATO socket) powered from second battery and switchable whenever needed (no neutral interlock etc.)

Winch (transmission) still protected by existing interlocks

Aux fusebox for additional 12V loads on second battery

Battery monitoring on second battery

Allow for high current supply to inverter from seconf battery

It was actually pretty simple even without a wiring diagram - although this sort of thing is pretty related to the day job.

I rewired the second (5 way) high current fuse box to be powered from the second battery instead of the main battery - this moved the power supply for the NATO socket and grey aux relay / fuse box to the second battery.
I rewired to input to the CTEK unit to come from the main (7 way) high current fuse box.
I added a small aux fuse box powered from the 5 way high current fuse box.
I rewired the power supply to the RI03 relay so that it comes from my new aux fuse box instead of from FI04 - this is the red wire going into the interior electrical centre fuse box wher a fuse used to go. This powers the front and rear 12V outlets, read USB outlets, front footwell outlets and EXT1 under bonnet outlet and the lights in the aux switches of the roof console.
I cut the wire from the EXT5 relay output under the grey fuse / relay box and wired it directly to the positive coil connection of the Albright relay - the NATO socket is now under control of the EXT5 switch. I need to replace the fuse on this with a 5A one.
I added a Victron Smart Shunt battery monitor to the ground line from the second battery - I can now precicely monitor its state of charge.
I removed the 300A single fuse between CTEK output and second battery and used a 300A Z Case fuse in the 5 way high current fuse box instead.
I added additional lighting in the rear load space and am output for a fridge from the new aux fuse box.
I also got rid of the top panels of the under seat electrical enclosure and secured the front panesls with cable ties - the whole under seat enclosure is a crap design which would get any of my engineers fired.

View attachment 7829456
View attachment 7829457
View attachment 7829458

Tristan

Hello Tristan, thanks alot for taking the time to document your modifications. I have read the description but I noticed that some of the components you describe are not present in my Grenadier (two-seater commercial with dual battery and high power swicth panel and additiona charging points. What I'm missing is what you call "grey fuse box / relay box" (that is the round box on the right side near your new fuse box). Is that from factory? I could not find the corresponding relay in my configuration, even though the Nato outlet can be switched on and off, hence there must be a high current relay somewhere in my car. What I did so far is adding philippi current sensors for the starter and service battery, A dual output AC charger to charge both batteries, a solar charger for the service battery, a battery protection for the service battery and seperate fuse boxes for starter battery, service battery, and battery protected service batterxy, from which I power the corresponding circuits (air parking heater, compressor, internal lights, battery and tank monitor, additional USB chargers, compressor fridge). I would also like to move the internal and external roof panel controlled outputs to the (protected) service battery but keep the Nato plug, where it is (to be able to jump start the car via Nato plug). Since Ineos is unwilling (or unable) to share details I desperatly search for more details. So any advice/additional documentation you might have available would be highly appreciated. Below some pictures showing (almost) the current state.

Jean Mercier · Nov 3, 2023

bnebenda said:
the Nato outlet can be switched on and off, hence there must be a high current relay somewhere in my car.

The "Allbright" relay for the NATO plug is located behind the rear right hand panel, pictures in this thread.
You can find some other pictures on the forum of the removal of the trim, but I posted it also in the French speaking part of the forum here.

bnebenda · Nov 3, 2023

Jean Mercier said:
The "Allbright" relay for the NATO plug is located behind the rear right hand panel, pictures in this thread.
You can find some other pictures on the forum of the removal of the trim, but I posted it also in the French speaking part of the forum here.

Jean Mercier said:

The "Allbright" relay for the NATO plug is located behind the rear right hand panel, pictures in this thread.
You can find some other pictures on the forum of the removal of the trim, but I posted it also in the French speaking part of the forum here.

Click to expand...

Can you confirm, that the wire marked with the green cross is the one that goes to the input of the relay?

Andrew Kilby · Nov 3, 2023

tristand said:
Hi All,

I have the factory dual battery setup and decided to make a few changes to the vehicle wiring to make it more useful. I wanted to have the following:

Front and rear 12V outlets powered from second battery

Rear USB outpets powered from second battery

All aux power supplies (under bonnet, roof and footwell) powered from second battery

Rear high power output (NATO socket) powered from second battery and switchable whenever needed (no neutral interlock etc.)

Winch (transmission) still protected by existing interlocks

Aux fusebox for additional 12V loads on second battery

Battery monitoring on second battery

Allow for high current supply to inverter from seconf battery

It was actually pretty simple even without a wiring diagram - although this sort of thing is pretty related to the day job.

I rewired the second (5 way) high current fuse box to be powered from the second battery instead of the main battery - this moved the power supply for the NATO socket and grey aux relay / fuse box to the second battery.
I rewired to input to the CTEK unit to come from the main (7 way) high current fuse box.
I added a small aux fuse box powered from the 5 way high current fuse box.
I rewired the power supply to the RI03 relay so that it comes from my new aux fuse box instead of from FI04 - this is the red wire going into the interior electrical centre fuse box wher a fuse used to go. This powers the front and rear 12V outlets, read USB outlets, front footwell outlets and EXT1 under bonnet outlet and the lights in the aux switches of the roof console.
I cut the wire from the EXT5 relay output under the grey fuse / relay box and wired it directly to the positive coil connection of the Albright relay - the NATO socket is now under control of the EXT5 switch. I need to replace the fuse on this with a 5A one.
I added a Victron Smart Shunt battery monitor to the ground line from the second battery - I can now precicely monitor its state of charge.
I removed the 300A single fuse between CTEK output and second battery and used a 300A Z Case fuse in the 5 way high current fuse box instead.
I added additional lighting in the rear load space and am output for a fridge from the new aux fuse box.
I also got rid of the top panels of the under seat electrical enclosure and secured the front panesls with cable ties - the whole under seat enclosure is a crap design which would get any of my engineers fired.

View attachment 7829456
View attachment 7829457
View attachment 7829458

Tristan

Awesome job. I don't have mine yet but was worried about how the dual battery worked. I don't think Ineos understand how a good dual works. You saved me a lot of time. Thanks again.

tristand · Nov 3, 2023

bnebenda said:
Hello Tristan, thanks alot for taking the time to document your modifications. I have read the description but I noticed that some of the components you describe are not present in my Grenadier (two-seater commercial with dual battery and high power swicth panel and additiona charging points. What I'm missing is what you call "grey fuse box / relay box" (that is the round box on the right side near your new fuse box). Is that from factory? I could not find the corresponding relay in my configuration, even though the Nato outlet can be switched on and off, hence there must be a high current relay somewhere in my car. What I did so far is adding philippi current sensors for the starter and service battery, A dual output AC charger to charge both batteries, a solar charger for the service battery, a battery protection for the service battery and seperate fuse boxes for starter battery, service battery, and battery protected service batterxy, from which I power the corresponding circuits (air parking heater, compressor, internal lights, battery and tank monitor, additional USB chargers, compressor fridge). I would also like to move the internal and external roof panel controlled outputs to the (protected) service battery but keep the Nato plug, where it is (to be able to jump start the car via Nato plug). Since Ineos is unwilling (or unable) to share details I desperatly search for more details. So any advice/additional documentation you might have available would be highly appreciated. Below some pictures showing (almost) the current state.

Hi,

The grey fuse / relay box box is circled in this picture:

The circular thing that you don't have is a remote monitoring system that my company manufactures (www.vircru.com) - they are normally used on boats but I'm using it to monitor and control various systems in the grenadier. It's not related to the power distribution wiring.

Tristan

DaveB · Nov 3, 2023

Andrew Kilby said:
Awesome job. I don't have mine yet but was worried about how the dual battery worked. I don't think Ineos understand how a good dual works. You saved me a lot of time. Thanks again.

They have installed a dual battery system, not a crank battery and a house battery system.

Clark Kent · Nov 4, 2023

DaveB said:
They have installed a dual battery system, not a crank battery and a house battery system.

I think that's an important distinction to highlight Dave, thank you.
We assumed Ineos would deliver a conventional dual-battery system where house loads are taken by the 2nd battery. In effect they have delivered a parallel battery arrangement. I'm not convinced there is anything wrong with Ineos' approach but as consumers we're struggling to understand it so want to convert it to a system we recognise. The lack of info from Ineos on their design approach and BMS operation is not helpful, but show me another manufacturer that provides that level of info to the end user.
I'm happy with what Ineos have done for my use case (touring, camping, not winching). I have added a D250S for solar input. I don't plan on making wholesale changes to the setup but I appreciate those that are because we will learn from their efforts.

Tazzieman · Nov 4, 2023

There is a strong move to portable energy systems. Cut out the auto elec middleman as well.
I've got a lithium battery in the post ; will be added to my multifunction box for a lightweight solution to everything.
And keep the factory dual setup just in case.

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Dual battery setup modifications

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Mr. Largo WINCH

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Xrford

tristand

tristand

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