Lithium battery installation (safety & codes)

[FMSports]

The unheated battery thread got a little heated when I said I would not install a battery bank or "ESS" inside and under a bed. I work in industrial plants as a P.Eng. and areas of safety risk have 1. Energy and 2. a confining space. This is the definition of an inside battery installation in an Airstream.

So looking into codes (California and Ontario for example), it's clear: Rule 64-918 4) prohibits ESS utilizing Li-Ion batteries from being installed in dwelling units, or any living space of residential occupancy, including closets, storage rooms, bathrooms, stairways, or in any similar undesirable places.


There was a comment that the Lithium Phosphate is a "safe" chemistry. However, the fire marshal has the goods on that here:

https://www.youtube.com/watch?v=YvQ9NEw76G8

As an engineer it struck me as being very odd that people were loading up Battle Borns under their front beds, seemingly without question. So for those looking for engineering advice, I would ask a PE/P.Eng/, Airstream engineering, or commercial solar installers and get their opinion on risks before moving forward.

[waninae39]

i am AN electrical Engineer and also a P..Eng.

i installed the batteries under the bed along with the Multiplus with safe firewall between them.

there is a small quiet muffin fan the moves air around the area.


i use overrated copper bus bars between the batteries
and 2/0 cable between the batteries and the lynx bars

in the last 4 years, i've never had a problem

[field & stream]

You recommend that users get advice from an engineer before moving forward with installing lithium batteries inside their trailers. As a self-described qualified engineer, perhaps you would share with this community how to design and install 400-600-800Ah of LiFePO4 lithium batteries (not Li-Ion) in a travel trailer application.

That would be constructive and appreciated.

[vanderwielen]

Originally Posted by FMSports

The unheated battery thread got a little heated when I said I would not install a battery bank or "ESS" inside and under a bed. I work in industrial plants as a P.Eng. and areas of safety risk have 1. Energy and 2. a confining space. This is the definition of an inside battery installation in an Airstream.

So looking into codes (California and Ontario for example), it's clear: Rule 64-918 4) prohibits ESS utilizing Li-Ion batteries from being installed in dwelling units, or any living space of residential occupancy, including closets, storage rooms, bathrooms, stairways, or in any similar undesirable places.


There was a comment that the Lithium Phosphate is a "safe" chemistry. However, the fire marshal has the goods on that here:

As an engineer it struck me as being very odd that people were loading up Battle Borns under their front beds, seemingly without question. So for those looking for engineering advice, I would ask a PE/P.Eng/, Airstream engineering, or commercial solar installers and get their opinion on risks before moving forward.

What are you attempt to accomplish? Some fire Marshall video supports your argument? Thousands of airstreams have batteries inside their rig. Hell, Airstream is installing 12kwH volta Sysytems in the Interstate. BTW, you can find a video, post or article on the internet that supports even the most ridiculous arguments.

[fran&frank]

So acorrding to the video, LFP batteries can fail at 300 to 400 degrees F. I don't think I'm going to be in my trailer when that ever happerns. Also I'd argue they are less likely to be penetrated inside and in the center of my trailer than on the tounge?--Frank

[uncle_bob]

Hi

If you are concerned with an active fire in the trailer *and* want to keep the batteries from adding to the problem, yup it's good guidance.

Simple answer in an AS:

If you already have that sort of fire going, you should be out of the trailer and away from it. You are at extreme risk if you still are in the trailer. A full up AS fire is not going to end well. That's true no matter how you set things up.

In terms of starting a fire: this is why you want a *good* BMS on your batteries. It's also why you want to pay attention as you wire things up.

Bob

[JeffKim]

Show me the crispy burnt campers. I'm a software engineer so I googled "LiFePO4 RV fires" - didn't find anything. I think it's good to not accept things at face value and do research, but it seems the only way batteries with this chemistry catch fire is if you basically burn them at high temperatures. So, sort of like having a bundle of wood under the bed.

There's a chemical explanation why this is true which goes something like:

The iron phosphate-oxide bond is stronger than the cobalt-oxide bond found in other lithium chemistries, so when the battery is overcharged or subjected to physical damage, the phosphate-oxide bond remains structurally stable and does not release excessive heat.

A deeper explanation requires more googling, however.

[FMSports]

The unique part of the system is cells contain all that is needed to burn up, and they do so rapidly.

So we have family (wife and kids) sleeping over top of combustibles, under which potential "bombs" are actively connected and being charged.

Potential compromising issues are:
- manufacturing faults
- charging or electrical malfunction
- mechanical damage

It's plain logic that states there is a risk here, even if remote, and that is borne out in current building regulations. E.g. the installation rules around Tesla powerwalls.

I looked at a presentation by NASA engineers on what they are researching to make cell configurations "fail-safe". It's quite the deal. I would say similar standards be applied if installing battery banks inside an RV sleeping space. Not much room for error when you are sleeping on a big energy bank.

The easiest work-around would be to cable connect a portable battery bank @ front of trailer. Has anyone done that?


ps: NASA has never had an issue with Li-Ion... “NASA has an exceptional track record but Boeing’s experience made us realize we need to be prepared to manage the catastrophic hazard rather than trust it won’t occur. When that one cell goes off, it’s like a blow torch; it pops, but if we can ensure that blow torch doesn’t impinge on its neighboring cell, we can prevent thermal runaway propagation.

[uncle_bob]

Originally Posted by JeffKim

Show me the crispy burnt campers. I'm a software engineer so I googled "LiFePO4 RV fires" - didn't find anything. I think it's good to not accept things at face value and do research, but it seems the only way batteries with this chemistry catch fire is if you basically burn them at high temperatures. So, sort of like having a bundle of wood under the bed.

There's a chemical explanation why this is true which goes something like:

A deeper explanation requires more googling, however.

Hi

If you go back far enough, there are examples of "crispy RV's". You also have examples of battery setups with no BMS and some very questionable charging approaches. Combine those with (possibly) questionable wiring and the results could get exciting.

Turns out that some of the cell construction practices back then also combined with a lack of understanding from the folks making the 12V batteries to create issues. This was not quite as common as BMS related fun and games.

I have friends who (very early on) took some Lithium cells (not LiFePO4) out to see what the issues might be. Short them and yup, they got dramatic results. The safety practices on their assembly line got adjusted as a result.

So, yes, you can have problems. The construction of these 12V batteries is not regulated. There really are no standards on them. You get whatever some group of folks decided to put into the design. In a "save every penny" sort of market, this almost inevitably will get us back to the "bad old days" on some examples.

What to do?

There are folks who tear this stuff apart. They put up the results for all to see. Some of what they find is pretty awful. Are they pros? Nope, these are amateurs doing the best they can. They can't really do a deep dive on the BMS the way they do on construction and wiring. Still, their info is better than having nothing at all.

Is there a risk? Sure there is. Going out the front door is a risk. Staying inside is a risk. There are no "zero risk" approaches to life. There are similar risks associated with *all* the alternatives in powering an RV.

Bob

[field & stream]

Yes, there are risks with ALL of the optional ways to power an RV, and electrical fires as a class are the number one fire risk in RV’s. The only way to eliminate the risk is to have an unpowered trailer, like my vintage one.

In my opinion, the problems with the OP’s posts are 1) the repeated references to a much higher risk technology than LiFePO, and 2) the exaggerated, sky-is-falling tone.

Is it better to have the power source outside (like the propane tanks)? I think so — it is where mine is. But, like everything else in trailer life, there are lots of trade offs.

[RWitherspoon]

In my younger days, I used to do high speed motorcycle riding with other geezers on abandoned highways. When my wife told me to be carefull, I would say 1. Speed 2. Fun 3. Safety.
It's the same for my AS power plan. A Honda generator and lithium battery bank that reside in the back of my truck. Why? Well 1. we have a building company, so job site. 2. we live on Vancouveer Island where tall trees and wind storms mean lights out 6-10 times a year (once was over 24 hours). 3. Camping without unhooking is a good percentage of our travel. You Mercans call it boondocking, we call it "sh*t this is a nice spot, why not stop here".

My fire risk is massive, fast moving forest fires coming from west of us, so our safety plan is, lots of insurance and to be gone in the AS in 5 minutes.

We also live on 12 volts with only the microwave needing 120, so a portable solar system is our quiet solution. Can't mount it because we park under trees 90% of the time.

I fly fish, and batteries power my "tin boat", nothing better than a morning of catch and release trout fishing, many of the nicest lakes don't allow gas motors!

Lastly, we have the world's dumist government, they have banned a lot of the Airbnb's in BC. We have lost an estimated 19,000 bedrooms for tourists to use, which means campgounds are already booked for the year, hotels are $600/night. So I plan to camp this year, but mostly without shore power.

[LNBright]

The gasoline in the tank in your vehicle is much more dangerous, best not get out on the road where people are driving at 60, 70mph….

And you’ll have to avoid switching to a BEV, if the gas concerns you.

Sell the camper, stay home, much safer.

[FMSports]

No sky is falling here. I'm stating the obvious, when I see no evidence of that info being offered.

Gas tanks aren't too bad if the fuel stays contained. At least that's what happened with my "safe" Volvo R-wagon. It did not blow up, just incinerated. Volvo could give two hoots btw. A $1 check valve missing in a vacuum line to prevent a compromised turbo valve from pulling air.

Propane needs respect - is heavier than air, so it pools low like water and there is a lot of energy in it. Like 2 1/2 times natural gas or CH4.

Look at what Boeing did with the Dreamliner after their battery packs burnt up. They enclosed the battery pack, increased space, provided an option for venting.

A morning adventure:

https://www.youtube.com/watch?v=SzgzEBmkkf8

[JeffKim]

One anecdotal data point, my first set of LiFePO4 batteries I shorted out when the positive came in contact with the metal battery case which was grounded (oops). I took them apart and found it burnt up the BMS, but nothing else. In fact, I bypassed the fried BMS and they worked just fine. We kept using them until I got replacements.

[ZeGermans]

Statistically (yes normalized) more ice cars are catching fire than bevs so there's that myth gone...

[field & stream]

OP — you are more than welcome to deny that your posts don’t have a “sky is falling” tone to them. It is the feeling I get. However, you undermine your denial of inflammatory messaging a bit when your posts contain color photos of things engulfed in flames.

Personally, I am far more concerned about non-battery shorts, the propane stove, propane water heater, propane furnace, tires, wheel bearings, road hazards, wind, weather, and all of the idiots and maniacs that we share the road with.

[G8trwood]

A better conversation from the experts would be on proper fusing, wire and switches.

[FMSports]

Well BMS, hook-up and fusing I would consider that first line of defense.
You need a back-up to allow for a wake-up alarm and escape. As temporary measure, I would get smoke and heat detectors installed in the compartment that houses the batteries.

Fire suppression is used in racing - googled and found this:
https://www.statx.com/application/ba...RoCn3kQAvD_BwE


Until proper redesign or removal/relocation is done.

The brand spankin' new Classic 30RBT in this clip, I own that actual trailer atm. Thanks to the fire crew, taillights aren't melted or anything. What was PO doing, benching an Li bank in the garage? She says the fire is electrical. Or did the trailer overload the house circuit?

https://www.instagram.com/p/CKPKF5Oj...RlODBiNWFlZA==

[FilmGuy]

Originally Posted by FMSports

…

The brand spankin' new Classic 30RBT in this clip, I own that actual trailer atm. Thanks to the fire crew, taillights aren't melted or anything. What was PO doing, benching an Li bank in the garage? She says the fire is electrical. Or did the trailer overload the house circuit?

https://www.instagram.com/p/CKPKF5Oj...RlODBiNWFlZA==

What has this clip got to do with this thread? There is nothing in the clip or the comments that suggests the fire has anything to do with lithium (or any other kind of) batteries. As far as I can tell, the fire doesn’t even involve the Airstream, it seems to be in the garage. Am I missing something???

[G8trwood]

Originally Posted by FMSports

Well BMS, hook-up and fusing I would consider that first line of defense.
You need a back-up to allow for a wake-up alarm and escape. As temporary measure, I would get smoke and heat detectors installed in the compartment that houses the batteries.

Fire suppression is used in racing - googled and found this:
https://www.statx.com/application/ba...RoCn3kQAvD_BwE


Until proper redesign or removal/relocation is done.

The brand spankin' new Classic 30RBT in this clip, I own that actual trailer atm. Thanks to the fire crew, taillights aren't melted or anything. What was PO doing, benching an Li bank in the garage? She says the fire is electrical. Or did the trailer overload the house circuit?

https://www.instagram.com/p/CKPKF5Oj...RlODBiNWFlZA==

All the prebuilt batteries have a bms (victron is exterior add on. Some batteries like the big epoch now have an internal class T (new marine requirements for lithium) fuse. Now if it is a dyi build, who knows,

There is some debate on whether a class T is needed for 12v systems, but I am not smart enough to opine vs a terminal MRBF. I have a 100a fuse on each (2x) battery + terminal. I don’t require max current as I was looking for run time.

Allegedly victron is coming out with a Lynx power in or distributor that will accept Class T fuses as opposed to the mega fuses. That would simplify some connections.