Adding a third battery.

[Zimm]

I think I'm going to add a third battery and put it in the drawer system to handle "camping" loads.

I know nothing about automotive/rv battery systems, so before I spend 3 days down the rabbit hole, do any of the wiring GuRu's have a recommendation on say... removing the existing dc/dc and adding one that can handle an additional renogy 300ah lipo, orrrr, should I just add a second dc/dc off of the second battery? No real plans to add solar, but if its there it's there.

Any thoughts appreciated.

 

[Znarfgh]

I use something like this with a DC/DC charger built into the box. 100Ah Lithium battery.

I have left the existing dual battery system well alone to avoid any potential warranty issues. After the warranty expires, I will change the system to a more traditional dual battery system.

I use a triple Anderson plug to power the DC/DC charger and all the ancillaries are run off a 12 gang fuse box which is connected to a single Anderson plug. The whole system is easily disconnected and can be used in other vehicles.

 

[Zimm]

I use something like this with a DC/DC charger built into the box. 100Ah Lithium battery.
View attachment 7883496
I have left the existing dual battery system well alone to avoid any potential warranty issues. After the warranty expires, I will change the system to a more traditional dual battery system.
View attachment 7883497
I use a triple Anderson plug to power the DC/DC charger and all the ancillaries are run off a 12 gang fuse box which is connected to a single Anderson plug. The whole system is easily disconnected and can be used in other vehicles.

I have the same concerns. So you’re just running the system in parallel. Where is your positive tap point to feed this second system? I have a tembo tusk drawer system that was given to me years ago, and it’ll fit the short Gren load area, and I noticed it actually has an area behind the drawer for the battery, so I’m just going to jam all the electronics in there.

Thanks.

 

[TheDocAUS]

I also use a Battery Box if needed. I have not used it in the field yet, but it was in the car yesterday being tested.

View: https://youtu.be/6NCvx92AgVI

Some models and reviews of Battery Boxes here.

 

[DenisM]

I have the same concerns. So you’re just running the system in parallel. Where is your positive tap point to feed this second system? I have a tembo tusk drawer system that was given to me years ago, and it’ll fit the short Gren load area, and I noticed it actually has an area behind the drawer for the battery, so I’m just going to jam all the electronics in there.

Thanks.

There is a 40amp fused cable outlet in the battery compartment under the rear seats. The cable is a similar setup to those in the footwell: sealed ends and taped to a loom. The three wires are 12v "live", 12v ignition switched and an earth. The outlet is suggested by Ineos for use as an air compressor connection ...

I'm in the process of using it to charge my "diy" battery box, using the ignition activated 12v wire as the signal source for the smart alternator -dc charger setup.
The battery box chassis is a metal 'first aid' cabinet from the local hardware store.

The 12v outlets comprise 2 'merit' sockets, a standard 12v cig. socket with 5v 2.1A USB plug-in adapter and 2 Anderson plugs (grey). The red Anderson is for alternator input to dc charger, the yellow Anderson for solar input. Blue Anderson on top at the rear connects to the 100AH LiFeP04 battery.
Apart from the Victron smart meter, there's also a Bluetooth 500A smart shunt inside the box.
I'm contemplating how I might repackage the whole lot, including the battery in a suitably sized "Pelican"-style case....View attachment 7883526

 

[Zimm]

I also use a Battery Box if needed. I have not used it in the field yet, but it was in the car yesterday being tested.

View: https://youtu.be/6NCvx92AgVI

Some models and reviews of Battery Boxes here.

I had considered one of those, but, I have otherwise inaccessible space the size of a battery in the drawer system I've decided not to toss out for now. Life was easier with 3 group 27 lead acids and an automatic battery system. Now I've got a mishmash of sizes, chemistry, and a smart alternator, which I would toss for a 250a GM 1 wire any day.

 

[Zimm]

I have a question for ya TheDocAUS, I haven't dug into the wiring yet, but I take it the ctek merely permits OEM battery 2 to trickle charge battery one when it detects the need? In some ways it seems this system is the worst of all possible setups. I always used a system where I could flip a switch and combine them for a jump, or when when winching If I thought best. Any thoughts as to why I couldn't just put a 500a contactor separating 2/0 between them in parallel to the ctek, and functionally bypass the ctek when I see the need? In fact... If battery one and two are the same, why couldnt I just eliminate the ctek and put an automatic dual battery controller between them like a traditional setup? Does the "smart alternator" hav some sort of issue if the batteries are directly connected?

 

[Rok_Dr]

That's a pretty neat set-up @DenisM. I'm contemplating a simpler version using just a Redarc Alpha DC-DC charger, If/when I go the third battery in a box route.

One question, what is the type of socket/plug you used for the smart alternator signal wire?

Cheers
Steve

 

[Rok_Dr]

I have a question for ya TheDocAUS, I haven't dug into the wiring yet, but I take it the ctek merely permits OEM battery 2 to trickle charge battery one when it detects the need? In some ways it seems this system is the worst of all possible setups. I always used a system where I could flip a switch and combine them for a jump, or when when winching If I thought best. Any thoughts as to why I couldn't just put a 500a contactor separating 2/0 between them in parallel to the ctek, and functionally bypass the ctek when I see the need? In fact... If battery one and two are the same, why couldnt I just eliminate the ctek and put an automatic dual battery controller between them like a traditional setup? Does the "smart alternator" hav some sort of issue if the batteries are directly connected?

The Ctek does a bit more than just trickle charge the starter battery from the Auxiliary @Zimm . It will also connect to jump start if needed. The following extract from my manual gives a fuller description

The Smartpass operates as follows. This is summarised and modified from the Smartpass user manual (Ctek 2019) to reflect the Ineos installation.

• Charging auxiliary (service) battery from the alternator (constant charging voltage):
  • The SMARTPASS 120S charges the auxiliary (service) battery at up to 120A from the start battery when the alternator is running.
  • This function is switched off when the engine is not running.
• Start assistance:
  • SMARTPASS 120S automatically connects the auxiliary (service) battery to the starter battery for 10 sec to assist if the starter battery on its own is unable to start the engine.
  • After the start assistance function has been activated, SMARTPASS 120S will display a fault indication until starting has been achieved without using the start assistance function.
• Separation of the starter battery and the auxiliary (service) battery:
  • SMARTPASS 120S separates the starter battery from the auxiliary (service) battery when the engine is not running.
• Dynamic overcurrent protection:
  • SMARTPASS 120S has overcurrent protection to shield the product. Overcurrent protection permits up to 350A to be sent from the alternator temporarily so that charging will be accelerated.
• Battery temperature protection:
  • SMARTPASS 120S protects the battery by switching off charging if the auxiliary (service) battery temperature rises too high.
• Starter battery trickle charging:
  • The auxiliary (service) battery trickle charges the starter battery to compensate for the self-discharge of the starter battery.
  • The auxiliary (service) battery charges in periodic 3-second pulses when its voltage is higher that of the starter battery and the voltage of the starter battery is low.
  • Note: I have had ongoing conversations with Ineos Support and their understanding from Ctek engineers is that the Smartpass will terminate this function when the Auxiliary battery charge drops to 50%. They have also advised that they plan to undertake testing to confirm that this is the case. This information is therefore provisional pending Ineos’s final advice.
• Auxiliary Battery Charging.
  • The SMARTPASS will start or stop charging the auxiliary (service) battery when the following voltages are seen by the unit. Note INEOS do NOT connect the red smart alternator wire.
  • Cut In: >13.1v for 5 seconds (engine running, alternator charging).
  • Cut Out: <12.8v for 10seconds. (engine running, alternator not charging).

Cheers
Steve

 

[ForceV4]

I think I'm going to add a third battery and put it in the drawer system to handle "camping" loads.

I know nothing about automotive/rv battery systems, so before I spend 3 days down the rabbit hole, do any of the wiring GuRu's have a recommendation on say... removing the existing dc/dc and adding one that can handle an additional renogy 300ah lipo, orrrr, should I just add a second dc/dc off of the second battery? No real plans to add solar, but if its there it's there.

Any thoughts appreciated.

Hey Zimm - I routinely deal with additional batteries in my snow plow vehicles and it doesn’t take much. As long as you’re stacking batteries in PARALLEL (meaning you are doubling the amperage - not the voltage), you will be OK without additional modifications to the electrical system. Your alternator will charge both batteries, albeit at half the rate. I do it because I run heat/defrost, lights, radio, plow hydraulics, wipers… (not in the Grenadier) and that second battery is a life saver!

Just don’t hook up an additional battery in SERIES… this will double your voltage causing damage. A quick check online showing the meaning of parallel v. series terminal connections is easy to find. Finding a spot to “hide” a second (or third) battery on a grenadier will be the trick. -Mark

 

[Zimm]

Thanks. I have the series parallel down. what I don’t know is what the “smart alt” is doing, and what the creek is doing, and what they looking at, so I don’t know how one or the other going to react (or what warning lights will go off) if I suddenly toss a battery in parallel to lessen the load on the primary battery while winching.

My plan was for a dual motor gigglepin winch, and a third battery for house loads. Simple and robust battery combining is what I need. The portable boxes are nice but a waste of space for my situation, so I’m trying to avoid that.

Since the two batteries supplied are alike, maybe I’ll rewire them with an old school separator, and utilized the ctek for the additional lithium battery. The old style just monitors voltage difference and combines them within the parameters preset. I don’t know if they will play nice with a smart alternator if it’s varying voltage output, which is what they do compared to a constant voltage alternator, right?

 

[DustCloud]

I use a Kings BatBlock25 which offers a prebuilt version of some of the solutions/brands above, running it from the Ineos second battery (mainly because it was easier to connect to and didn't require disconnection of battery from car, and using the ignition active wire from the 40A spare 'compressor' lead. I did think about using that for the power too but in the end decided to pull the load as directly from the battery as was possible.

I also took the BatBlock 25 to pieces to check its build quality and noted the two 50A Anderson sockets for in/out share a single 50A fuse and wiring, and the 3 12 volt sockets share a single 15A fuse. Not of concern for my use case but I definitely recommend understanding the internals and also knowing which fuses to keep on hand for spares.

And lastly I swapped out two of the 12 volt sockets for 100w USB C PD (20V) so I can charge laptops, phones, and run Starlink mini.

 

[TheDocAUS]

I also took the BatBlock 25 to pieces to check its build quality and noted the two 50A Anderson sockets for in/out share a single 50A fuse and wiring, and the 3 12 volt sockets share a single 15A fuse. Not of concern for my use case but I definitely recommend understanding the internals and also knowing which fuses to keep on hand for spares.

A must do in my book. A quick way to identify when shortcuts are taken.