LiFePo Batteries in Utility Room
sabotcat
| Posted in Building Code Questions on
I’m putting in my largest solar array/inverter/battery system so far. And frankly the first that will be seen by an inspector.
The location everyone likes for the batteries is in a room with a washing machine. Is that viable? these are fortress batteries so they’re UL9450A rated and I think they’re IP65 outdoor rated as well.
in California, does anyone know if this is a non starter? Do I need to get them off the ground? What do you all think?
I’m being told I can do it…and it just makes me wonder. Like Reagan said, “Trust but verify.”
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Large batteries are a fire hazard. When Li batteries burn, they release toxic smoke and are difficult to extinguish to say the least.
It is hard to know if your local code has been updated to recognize the risk large batteries pose and if the inspector that happens to visit will spot the risk and know what if any codes to apply.
What does the installation instruction for this batterie say about your questions?
Generally, a Tela power walls get installed in garages because code requires a fire wall between the garage and the living space also code prohibits HVAC supply and returns in the garage.
Walta
Walta
Thanks for the quick response. You make a good point about the old lithium ion batteries. on these, manufacturer recommends 4 inches from a wall +/- and 5 inches apart. The 9450A rating from UL means that they resisted ignition and fire did not spread to adjacent cells after forcing thermal runaway by charging at 5C until failure. So these are pretty well protected. And the fire code in CA acknowledges that. EE that's designing the system has never seen a problem with inspectors when there is a washing machine across the room...but you never know. I was curious if anyone had experience with Fortress Batteries with and IP55 rating and UL 9450A.
Just because they have "never seen a problem" doesn't mean it's not worth taking some precautions just to be safe, especially with a relatively new product that doesn't have a lot of history yet. You are correct that the newer LiFePo batteries are safer, but they do still carry some risk. I typically recommended installing any large battery pack in a fire rated room, ideally with some exhaust ventilation too. A basic room like this needs 5/8" type X drywall on all sides, including the ceiling, and needs to be sealed off from the living spaces. Two layers of 5/8" drywall gets you more protection. Remember that drywall is pretty cheap, and what you're doing here is building in some fire protection as extra insurance just in case of any future problems.
Bill
Bill,
thanks. I'm totally with you on this. Regardless of the UL testing, the room will be fire rated. I'm just thinking about the introduction of a possible source of water with the washer. The other stuff the Fire Marshal has in had. As we'll be working at least to their specs.
I'm wondering in a drain in the floor would make everyone at the county more comfortable. Like you say, prepare for the worst. But in my case, the safety issue that isn't covered yet is a situation where the room fills up with 4 inches of water. Implausible on a hill in the desert. But nature taught me long ago that it was going to do whatever it wanted, no matter what mankind expected.
I would not put a battery on the floor, that is asking for trouble. Wall mount it at least 6" off the ground.
I would also double check with your local safety authority, they might not allow batteries that are not specifically marked for residential use (UL cert by itself is not enough) to be installed inside a dwelling unit. Even if marked, basements might still not be allowed.
akos,
good point. Do you think the add'l two inches might be enough to satisfy an inspector regarding water danger. The batteries are 4 " off the floor already. But another two wouldn't hurt. of course we have to stay 4 inches from the wall per code where I am.
I'm just looking for anyone who knows code well enough to tell me if there is anything specific about UL 9450 IP55 batteries sharing a room with a washing machine.
Akos,
that's the hardest thing to nail down. I've got a couple of emails out. Happily with batteries from the US I can put them into the plan and see if the County will pass them. If not...then I'll circle back to outside the house ideas.
I'm pretty sure that if a battery is allowed inside a dwelling unit, it needs to be in a dedicated utility room. You can read through NFPA 855 to find out if a washing machine would be allowed in there.
> The location everyone likes for the batteries is in a room with a washing machine.
Is the washing machine coincidental to why they like that location?
LiFePo batteries are passively cooled so you'll want to make sure they get enough air flow. Easiest way is to mount them outdoors.