Has anybody ever considered home battery safety in relation to where they place their Energy Solar System (ESS) backup and how quickly they are able to:

1. Evacuate a battery experiencing thermal runaway?
2. Physical access to safety in the event of a fire?
3. Ever-changing regulation and being pre-emptive in terms of safety?

Here's an article of what is happening in some parts of Australia I thought would be useful to the forum.

https://www.solarquotes.com.au/blog/home-battery-safety-plan/

1 hour ago, Moffat said:

Has anybody ever considered home battery safety in relation to where they place their Energy Solar System (ESS) backup and how quickly they are able to:

1. Evacuate a battery experiencing thermal runaway?
2. Physical access to safety in the event of a fire?
3. Ever-changing regulation and being pre-emptive in terms of safety?

Add to this "4. Wording of insurance policies". Don't assume the Ts and Cs never change.

A couple of years ago, the UK government published this:

Quote

Research and analysis

Domestic battery energy storage systems

A review of the safety risks of domestic battery energy storage systems and measures to mitigate these.

https://www.gov.uk/government/publications/domestic-battery-energy-storage-systems

Some might find it interesting. 🙂

1 hour ago, Bobster. said:

Add to this "4. Wording of insurance policies". Don't assume the Ts and Cs never change.

Insurance Ts&Cs are, in my book, just a method for manufacturers and most entities ways to "sneak out" of some regulatory laws and throw the responsibility all onto the end-user, yet without fail, they are like bird chicks with mouths open, wanting to be paid their premiums.🤦‍♂️

8 hours ago, Moffat said:

Has anybody ever considered home battery safety in relation to where they place their Energy Solar System (ESS) backup and how quickly they are able to:

1. Evacuate a battery experiencing thermal runaway?
2. Physical access to safety in the event of a fire?
3. Ever-changing regulation and being pre-emptive in terms of safety?

Here's an article of what is happening in some parts of Australia I thought would be useful to the forum.

https://www.solarquotes.com.au/blog/home-battery-safety-plan/

On Point 1, you will have to be a brave person to evacuate a battery that is experiencing a thermal runaway. It will be a lot safer to rather evacuate yourself.

1 hour ago, I84RiS said:

On Point 1, you will have to be a brave person to evacuate a battery that is experiencing a thermal runaway. It will be a lot safer to rather evacuate yourself.

True, but if one a gas detector and you could pick up a battery issue before you actually have the thermal runaway and if you had a pool at your residence plus nerves of titanium or steel who knows?😆

Smoke detectors are so cheap that it's common sense to fit one in the same area as the battery

Will a foam extinguisher moderate the fire?

Edited December 12, 20232 yr by chrisc

The (UK again) Fire Industry Association issued a 'Guidance Note' on Li-Ion Battery Fires which goes over the various options... 

TL:DR is basically that once you're in a thermal runaway situation, there's not a whole lot you can really do, other than get out.  Best bet is to try and prevent it getting to that stage in the first place, so effective monitoring and Gas detection would be the way to go.

There are products on the market that are specifically designed to do the job, but cheap they are not.

My personal preference is for 'domestic' Carbon Monoxide detectors (interlinked with the main house heat/smoke system).  I'm looking at ways to provide alerting (on excessive temp deviation) that doesn't partly rely on a functioning internet connection, as it currently does.  It may or may not involve an old car horn. 🙉

Ideally, my batteries would all be located outside of the main living space, in an area that's not going to impede rapidly exiting the house - unfortunately due to climate and other issues, they have to be within the heated area of the property.

I've only experienced a single 18650 cell going off (my fault, I was abusing it) and that was scary enough - I managed to pick it up with pliers and throw it (and the pliers) out of the window - I don't think I've got any pliers big enough to deal with something a few thousand times bigger. 😬

Been in the rc hobby for many years  mostly electric powered with lithium (lipo)batteries . Seen these lithium go up in flames more than ones so when these lithium have a runaway it happens so quick that by the time an smoke detector picks up smoke battery and  everything around the battery is on fire .

So it's not a good idea to go even close to that battery when they start to make smoke .

And fire extinguisher has very little effect , all that an fire extinguisher can do is reduce damage to surrounding object . 

Fortunately these lithium are in an metal box . 

Edited December 12, 20232 yr by GMAC

You’re right about the speed of a battery gassing & then going into a thermal runaway… the worry is that most of these batteries are encased in steel & if BMS fails, there’s hardly enough time or warning. The other challenge is location of batteries. They don’t do well with high humidity or high outdoor temperatures or in some locations, worse still freezing temperatures yet regulators just want to saddle users with unrealistic regulations, which become costly. Solar is costly enough, outside of having to comply with certification & safety rules. 

I hadn't realised until now that you can get extinguishers specifically for tackling Li-ion fires. 

Trouble is, going off their rating, I'd need about 70 of them (@£380 GBP each).  😲  It would be cheaper to just build an extension to the house. 😁

This caught my eye the other day while shopping. It's not for extinguishing lithium fires, but does extinguish electrical fires, which could help prevent an electrical fire reaching the batteries causing a more serious disaster:

https://www.takealot.com/afo-fire-extinguishing-ball-fire-suppression-device-2-pack/PLID92543174

On 2023/12/13 at 2:52 PM, jumper said:

This caught my eye the other day while shopping. It's not for extinguishing lithium fires, but does extinguish electrical fires, which could help prevent an electrical fire reaching the batteries causing a more serious disaster:

https://www.takealot.com/afo-fire-extinguishing-ball-fire-suppression-device-2-pack/PLID92543174

These fire suppression balls may help but if you have to employ them, chances are your installer didn't do a great job on your installation with correct breakers, surge protection devices on both the A/C and D/C side because truly if any issue starts from within the battery not much can be done once thermal runaway begins. But yes if the fire may be coming from somewhere else, gas cooker or something, they would come in handy to protect the fire from getting to the batteries. Just reflecting on how the BYD blade battery for vehicle EVs is touted as "very safe" even when punctured or the new Qili battery which is touted withstand extremely high and extremely low temperatures. Such if true would be exciting for the home market.

On 2023/12/12 at 10:08 PM, chrisc said:

Smoke detectors are so cheap that it's common sense to fit one in the same area as the battery

Will a foam extinguisher moderate the fire?

Once thermal runaway begins it's only a matter of getting out of the way and foam or water will not really do much. Best would be to ensure you have an exit route out of your building or home that is uncluttered and has easy access, which also can be difficult as you have to be considerate of security to keep thieves out...

It is really worrying having 125kg of lithium at home.

In my case, there is a smoke detector and the whole system is installed in a concrete basement room, isolated from the house by 2 FD-120 doors.

If the smoke detector triggers, the only thing I would do is ensuring the doors are shut before running away and calling fire brigade 😂

LifePO4 in home use is very safe, user would have to do some really strange $h%& to make them fail catastrophically.

Most of the EV and home storage fires have been with other chemistries e.g. the 18650 lion cells, those things are pretty dangerous in storage solutions when they go south.
There are some really cool youtube vids of testing the different chemistries especially puncture and over charging tests that show how the different chemistries behave.

My Favourite

 

Edited December 18, 20232 yr by WannabeSolarSparky

3 hours ago, WannabeSolarSparky said:

LifePO4 in home use is very safe

I tend to agree.  One thing that was clear in the UK Gov study I linked to above, is that they were struggling to find any instances of a fire directly attributable to the battery. 

Also the amount of effort the firefighters in your video put in to abusing the LFP, and it still won't burn.  I like the way that at the end of the 'combustion' test, one of them even sticks an axe into it for good measure. 😁  All quite reassuring, really.

I'd still like to see some 'real-world' tests, though.  See how they stand up to  the 'drunk Father-in-law who thinks he's an electrician', the 'incontinent dog marking his territory', or that most feared adversary of all: the 'curious 6-year-old boy with a stick'.  😬

Lithium batteries hold a lot of energy for their size. That's a good thing for powering inverters, laptops cell phones etc, but bad if something were to go wrong. The reaction that releases electrical energy is unstable: It releases heat, and heat causes the reaction to go more quickly... which releases more heat... which causes more energy released, and then thermal runaway. If the reaction isn't controlled, all of the energy can be released in less than a second, leading to a fire or even an explosion. Things like discharging too quickly, overcharging, punctures, and internal short circuits can all cause a battery to fail this way. So lithium battery manufacturers add several stages of safety measures(Bms for one) to make sure nothing goes wrong. Some have even shot holes through a fully charged battery to make sure it wouldn't explode. But there have been a lot of problems in recent years with counterfeit batteries, which look like "proper" batteries from the outside but are not made with the same safety measures. If you're shopping for a battery and you find a price that's too good to be true, it's probably too good to be true!

Lithium polymer batteries are about the same as lithium ion batteries as far as safety is concerned. They operate with nearly the same chemistry, but using a gel rather than a liquid. Both types have vents to prevent buildup of excess pressure.