Adding 24V Tesla battery to RV? Outback 300ML

[theboneskes]

Ok, I bought a Tesla 24V 250AH battery. Im looking to build a battery bank... We have a 2020 Keystone Outback 300ML trailer. What is needed to convert my factory fuse panel/charger from 12V to 24V output, especially with a Lithium battery? And, then how do I convert back to 12V for my power needs of my trailer? Anyone do this? Pointers? Thank you!

[chuckster57]

It may have been done by somebody, but since your trailer is all 12VDC, the equipment needed to step down for use and installing a 24V charger is probably more than just using a 200Ah or even a single 400 Ah LiPo 12V battery

[TXiceman]

You will need a step-down transformer to drop to 12 VDC as that is what the RV uses. You will also need a 24 VDC charger for the battery.


Life would be simpler to just use a set of Lithium batters designed for 12 VDC and a charger suited to Lithium batteries.

Ken

[flybouy]

Using a step up transformer and a step down transformer to go to and from 24vdc to 12vdc is a very inefficient process.There will always be a loss of energy in that process. I'd advise you return that battery or sell it and purchase a 12vdc version.

[theboneskes]

I just bought 3 more modules, for a total of 1000AH. Paid $1400 for all 4 modules.

[chuckster57]

Post up pics of the results when you get it all wired up.

[JRTJH]

Originally Posted by theboneskes

I just bought 3 more modules, for a total of 1000AH. Paid $1400 for all 4 modules.

Now to find a SAFE way (remember, when boondocking, the nearest fire department may be 3 or 4 hours from finding you in the woods) to convert that "explosive lithium energy" to a safe and usable voltage for an "off the grid 12 volt RV system and then to safely recharge them when depleted.....

If those 4 modules are the same as the modules in electric vehicles in this video, I wouldn't want them strapped to the tongue of my Cougar, powered by a "homemade charging system and a make do voltage conversion system." YMMV.

https://www.facebook.com/fausto.pili...65264330546438

[sourdough]

Originally Posted by JRTJH

Now to find a SAFE way (remember, when boondocking, the nearest fire department may be 3 or 4 hours from finding you in the woods) to convert that "explosive lithium energy" to a safe and usable voltage for an "off the grid 12 volt RV system and then to safely recharge them when depleted.....

If those 4 modules are the same as the modules in electric vehicles in this video, I wouldn't want them strapped to the tongue of my Cougar, powered by a "homemade charging system and a make do voltage conversion system." YMMV.

https://www.facebook.com/fausto.pili...65264330546438

That egg is a long, long way from being ready to hatch...but I guess if it's mandated it's all OK?? LOL.

Met DS in Abilene yesterday to take him some stuff; met at a Hampton Inn. As I pulled off I20 I noticed a large green bus sitting on the side of the road...kind of odd but I was paying attention on getting where we needed to go. After we left I again "noticed" it but paid no attention. As we got on the interstate she asked if I had looked at it and told her not really. She said it said it was an electric bus and about the back 10-15' was completely burned out. Yeah, I want one of those things or a battery pack like THAT!! Heck, the batteries in our electric bikes are kept far removed from us or anything flammable.

[wiredgeorge]

Firefighting must take into account the volatile nature of lithium car batteries...

https://www.firehouse.com/operations...5G5B&rdx.ident[pull]=omeda|7666A3141845G5B&utm_campaign=CPS231020053&u tm_medium=email&utm_source=FH+Operations+%26+Train ing

[jsb5717]

No, no, and no. As stated, it's your rig but there's no way I'd risk doing a Frankenstein application with that kind of potential risk. It's just...no.

Play it more safely and buy products that are designed to operate the way the system is designed to operate.

[JRTJH]

Just a little "internet research is enough to scare hell out of me about trying this approach for "cheap lithium batteries" for a camper:

First, here's an article that gives the "lithium chemistry" for the "TESLA battery makeup. There's no indication from the OP of what type of "24 volt TESLA cells" he actually bought. If they are NCA or NCM, then they are "the explosive battery seen in the fires above. If they are LiPo, then they are much safer to use. Here's the link to what TESLA uses: https://insideevs.com/news/587455/ba...electric-cars/ The battery composition listing is near the end of the article.

Then there's the "safety/fire issues" surrounding NCA/NCM batteries. Simply put, unless handled correctly and installed/used properly, they are subject to spontaneous ignition and once the "rapid discharge chemical chain" begins, there's very little chance of stopping it. Here's the link to the "safety comparison": https://www.poweroad.com/knowledges/...n%20advantages.

Here's the "bottom line safety consideration" from the above article:

"In terms of safety, the LFP battery is generally superior to the NCM battery. The chemical properties and structural framework of the LFP cell itself are very stable. Even if it is penetrated, squeezed hard, and thrown from a high altitude, it will not catch fire or explode, but smoke at best. On the contrary, the safety of NMC batteries is much worse, especially under abnormally high temperatures, the possibility of fire and explosion is relatively large, which is also one of the reasons for the criticism of NMC batteries.

The winner is LFP

The safety of an LFP battery is one of its main advantages. At higher temperatures, lithium iron phosphate is a more stable alloy than nickel manganese cobalt.

Additionally, LFP batteries are better able to manage higher power pulls. LFP batteries are less susceptible to thermal runaway as a result. LFP batteries are less prone to catch fire than NMC batteries, to put it briefly.

Not that installing an NMC battery will cause it to spontaneously ignite. However, there is a greater risk of problems arising if an NMC battery is subjected to excessive stress or is handled incorrectly. To reduce the likelihood of anything going wrong, it’s crucial to have your batteries installed by a licensed, reputable professional."

For me, the most important takeaway would be that NMC batteries are not suitable for "amateur builders" to modify for RV use without extensive knowledge of how explosive they can become, in an instant....

The reason for changing to lithium batteries is to gain the ability to boondock far from the grid. That also means "far from any fire department response". That's not the ideal location to have "risky batteries"....

All said, the OP hasn't even disclosed what battery chemistry he purchased for his $1400 investment. He may not even know.

To the OP, you may have made an excellent purchase in terms of electrical storage capacity. But in that process, you may have started a project that could easily burn your trailer to the ground and risk your family's life in the process. You may be creating the device for your own demise. The fact that you posted the question about how to adapt these battery parts for use in your RV is a hint that you don't know much about electricity or battery safety. I'd urge you to PROCEED WITH EXTREME CAUTION !!!!!

For me, that's more like having a big bag of fireworks, not knowing where the fuses are located and setting that bag next to a campfire with sparks popping from the logs, landing all around our feet with the bag under one of our chairs..... IMO, That wouldn't make for a comfortable, relaxed "smores event". YMMV

[flybouy]

Originally Posted by theboneskes

I just bought 3 more modules, for a total of 1000AH. Paid $1400 for all 4 modules.

Good luck with that, I would suggest adding a second smoke detector and review/practice your "fire evacuation planes" regularly. Safe travels.

[nuctrooper]

Definitely doable. I'd look to Victron equipment to build out the electrical system. Use a 24V MultiPlus II 2x120 for the AC and the 24V DC charging, use an Orion DC-DC converter to feed the camper's 12V system. (and get rid of the factory converter). The Orion can output up to 70A @12V - that should be enough for most 12V systems (over 700W). If you have solar, Victron makes great charge controllers that work together with the multiplus. Add a Cerbo GX and a touchscreen, and you have a fantastic off grid ready setup.

Edit - if you have electric-hydraulic jacks you may need to get two Orion DC-DC converters (or three). They can be paralleled to provide 70A each, up to 5 units in parallel)

[theboneskes]

Ive decided for now to build a backup system for my house, incase? We have brownouts all the time in Columbus Ohio, and have a backup generator system on my house that I put it. Gonna experiment on a whole house battery backup system.

[theboneskes]

I bought 4 of these batteries for the Nay sayers...

[JRTJH]

Many maybe all TESLA batteries use liquid cooling to prevent thermal runaway. They use a glycol based liquid to pump through the battery, in winter the absorbed heat us used to warm the cabin, in summer, the heat is sent to a radiator and discharged outside the vehicle....

Have you addressed the cooling aspect for your "bargain batteries" ????

[nuctrooper]

A Tesla can pull 600kW from its batteries. An RV rarely pulls over 6kW. Even a home backup will rarely pull 10KW. And that is only in spurts - most of the time an RV is under 1kW steady state. I wouldn't sweat the cooling, just give them some air space. I have a lithium bank (just under 5kWh total) and can barely get the batteries warm running the A/C for 30 mins on batteries when boondocking in the heat. The Victron system has a battery temperature probe, and the bank doesn't get more than 5 degrees above ambient when charging or discharging. Lots of nay sayers about Li batteries - I absolutely love my setup and now never have to worry about energy, all thanks to Li (Dakota Li).

[nuctrooper]

Also, for the fire bug crowd - there are an average of 170,000 vehicle fires in the US every year. Yes, some are from electric vehicles, which garner a lot of attention - but gasoline vehicles are more likely to catch fire (I assume you would never drive a gasoline vehicle because of the risk of fire). Statistics here.

[sourdough]

Originally Posted by nuctrooper

Also, for the fire bug crowd - there are an average of 170,000 vehicle fires in the US every year. Yes, some are from electric vehicles, which garner a lot of attention - but gasoline vehicles are more likely to catch fire (I assume you would never drive a gasoline vehicle because of the risk of fire). Statistics here.

Can't tell much from the link. It wants me to accept their cookies and I don't. The superficial numbers I can see don't verify anything other than the number of vehicle fires which is meaningless.

I've caused a gasoline car fire (small) when I was young. I've seen a gasoline car fire and I've read of them. I've never read of a gasoline engine self combusting because it was "sitting" there which is what EVs like to do. Gas car fires are caused by people doing something stupid, EV fires "just happen" because - big, big difference. If something is going to fry me I want to know that I did it, not that a battery decided to self destruct and the fire dept. couldn't put it out. Not a fire bug, just logical.

[wiredgeorge]

Originally Posted by nuctrooper

Also, for the fire bug crowd - there are an average of 170,000 vehicle fires in the US every year. Yes, some are from electric vehicles, which garner a lot of attention - but gasoline vehicles are more likely to catch fire (I assume you would never drive a gasoline vehicle because of the risk of fire). Statistics here.

I am a Texas Certified Firefighter (retired) and the article I posted details the issues with fires from the lithium batteries. They can't be easily extinguished. The EVs that catch fire were designed specifically to use those batteries and a DIY set up, well wasn't. Calling folks "fire bugs" is a bit insulting. I have put out many gas vehicle fires and while they are no joke, the main hazard is the toxic fumes the cars spit out when burning. A lithium battery fire... well read the article as to why firefighters are concerned.