16 replies to this topic

[Murban]

I have a one-year-old ATC Ocelot with the original 78AH AGM Intimidator battery and a Renogy suitcase solar panel for recharging.  I would like to upgrade to 100 AMP hour Lithium battery.  From what I read on this forum I believe I should upgrade my wiring from the truck battery to the camper house battery. Has anyone done this, and could you share what you did to do to deal with the plugin connection of the truck to the camper and were you able to keep the battery isolator in the circuit?  I think I will need to add a DC/DC charger in the circuit somewhere.  

 

Should that be in the truck engine compartment close to the starter battery or in the camper?  My truck is a 2006 Tundra double cab and I want to be able to remove the camper in the winter for storage and maintenance.

 

I am not opposed to seeking professional help as my electrical experience is somewhat limited.

 

I did speak with Marty and they have not worked too much with Lithium battery set ups yet. I have an inquiry in to AM Solar but it has only been a few days so maybe I will hear back from them next week.

 

Anyway, appreciate any advice or direction for help.  Love our Ocelot.

 

Happy trails.

Edited by Murban, 12 June 2022 - 01:47 PM.

[Wandering Sagebrush]

Vic Harder, a WTW member, has done that upgrade to his ATC.  In the Electrical forum, there are several threads on the topic.  IMO, Vic is very knowledgeable and his thread is a great read. Reach out to him, I’m sure he would share.

[Ted]

Vic is very knowledgeable on things electric. He helped us when planning our Tiger build. Also, Ski3pin has converted his ATC to lithium. He may be able to answer questions as well.

[SkyP]

I would not mount a DC/DC charger in the engine compartment unless it was rated for very high heat and waterproof. I'm not aware of one that is.
My setup is a 20A Renogy dual purpose MPPT and DC/DC charger, charging a 100AH LiFePo4 battery, it is mounted in the ATC on the front wall under the lower bed. I'm feeding the MPPT part from whatever solar panel came mounted on the roof from ATC- not even sure what it is but it gets the job done, for me anyway.

Edited by SkyP, 11 June 2022 - 09:15 PM.

[Murban]

Thank you guys. I will reach out.

[CougarCouple]

Hello Murban

Upgraded our Cougar with one 100ah lithium, renogy 30amp dc-dc charger. Integrates the Solar and truck alternator charging with 6guage wire from truck battery to the renogy charge controller. Used a Anderson plug at the camper so can unplug the truck. A fused circuit breaker at the truck battery so can isolate the run to truck bed and protect wiring.
Very pleased and working well, this is reasonably easy. Hope this helps.
The renogy dc-dc controller has limitations like probably won’t be able to hook panels up In series. Also found the 150 watt panel not enough wattage to keep up with our consumption. Added a 100 watt panel (both renogy) and this will bring battery back to 100% by noon in the AZ desert use about 30% over night. (Panels need to be same size in parallel so I’m losing 50watts).
If I start the truck first thing in the am puts over 20 amps into the battery takes about 30 minutes to get back to 100%.

Good luck
Russ

[Wango]

Hi Murban,

I was in your shoes up until a month ago. The advice stated here is solid. Vic is an amazingly helpful guy. i was not wanting to do the work that i needed. KP, another member owns a company in Reno. I reached out to him, had my entire system redone and could not be more pleased. I would bet you will not regret an upgrade.

w

[BlueSky]

You have a couple of decision points here. One of them is upgrading to a LifePo4 battery, excellent choice and prices are coming down. Second should be to upgrade your solar panels and since you live in sunny CA, this is highly recommended (200w). Third is whether or not to do a DC-to-DC charger (which will eliminate the isolator you have now btw). The rest of it is just picking out the best components.

 

I did the whole shebang last year except the DC/DC charger.  The cost and complexity of DC/DC was a bit out of reach at the time. Instead I utilized the existing wiring so that if something went wrong with my LifePo4 battery I can easily disconnect it and connect the camper to the truck battery in a pinch. I can also charge the truck battery with the solar panels. So, I basically have a backup plan if something breaks in the LifePo4, which btw was what I thought was most likely. I live in sunny CO and most of my travel is in the sunbelt states so solar is king. If I lived in the PNW I would add DC/DC for sure.

[Murban]

Upgraded our Cougar with one 100ah lithium, renogy 30amp dc-dc charger. Integrates the Solar and truck alternator charging with 6guage wire from truck battery to the renogy charge controller. Used a Anderson plug at the camper so can unplug the truck. A fused circuit breaker at the truck battery so can isolate the run to truck bed and protect wiring.
Very pleased and working well, this is reasonably easy. Hope this helps.
The renogy dc-dc controller has limitations like probably won’t be able to hook panels up In series. Also found the 150 watt panel not enough wattage to keep up with our consumption. Added a 100 watt panel (both renogy) and this will bring battery back to 100% by noon in the AZ desert use about 30% over night. (Panels need to be same size in parallel so I’m losing 50watts).
If I start the truck first thing in the am puts over 20 amps into the battery takes about 30 minutes to get back to 100%.

 

Thank you Russ -

This is in line with what I want to do.  I'm thinking 1, 200 Watt panel on the roof, My concern with the roof installation is I do not like the SAE connector input that is the standard install for ATC.  I would want to change that out to something more robust.  Need to figure that out.

 

I would like to keep the ability of charging the house lithium battery through the truck battery and alternator.  That would necessitate the wiring upgrade to 6 AWG as you describe.  Did you have to do anything different going through the battery isolator?

 

I think I would also need a solar charge controller for the 200 W solar panel.

 

Thanks again.

Mike

Edited by Murban, 12 June 2022 - 03:01 PM.

[kmcintyre]

I built my own LifePO4 battery pack (120ah) and as others stated, you'll need (or want) a DC-to-DC charger to charge the batteries from the alternator.  You can get an isolated DC charger too.  I have a solar (backpack) we use when we aren't driving for a few days (actually ithe battery does great for about a week as we have propane refrig and don't use much power) and I installed a lifepo4 controller on it so I can just plug it in when needed.

 

Building a LifePO4 battery pack is really quite easy and cells are pretty cheap too.  The main expense is really the DC charger.  I have a write up I did a few years ago if you'd like it.  Just send me a PM and I can send it over.