Lithium batteries

[Alchemy]

I’ve read a bit of “stuff” about lithium and potential for fire, so found the below interesting. It’s a copy/paste from a yank FB page. Make of it what you like.

Sharing from the lithium on boats group:

Not everyone here is a member of ABYC, so I thought I would share this newsletter from them today regarding their tests of LiFePo4 batteries and potential for fire. This may be of interest to folks considering safety issues around lithium and discussing with surveyors.

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September 2022 Newsletter

ABYC President's Message

Common Sense

ABYC is built on a tradition of common sense and real world experiences. Early in my technical days, I was told ABYC designed the Standards so the backyard boatbuilder could achieve desired results. Testing and methodology were crafted in plain language for a “common sense” approach to a safe product.

We did not set aside best engineering practices for simplicity; the technical committee is packed with engineers and data-crunchers overseeing the process of drafting and updating the Standards. This balance has helped ABYC create useable, reliable, and relevant documents that help to achieve an unmatched level of safety in our industry. This is why, when the US Coast Guard asked us to look into potential problems with Lithium Iron Phosphate (LiFePO 4) batteries on boats, we jumped at the chance.

The ABYC Technical Department, with input from the industry, recreated a number of scenarios based on accident narratives that claimed LiFePO 4 batteries to be the cause of a fire. In our on-site test lab, our team subjected batteries to conditions ranging from “normal” operations to extreme use and abuse. We purchased units built for the marine environment with robust battery management systems. We also included recycled batteries available from mass retailers, with an “optional” battery management system and no clear instructions from the battery or cell manufacturer. We tried to replicate sketchy behavior which is the fear of insurance companies and regulators alike.

Do you know what we found? We couldn’t start the fire (Sorry Billy Joel). We witnessed swollen cells, completely dead batteries, and multiple safety cutoffs (when not bypassed). We had a very hot summer here in MD. Even the high heat didn’t come close to a spontaneous combustion scenario.

We arranged calls with industry experts, and we asked them what we might be missing in our testing. What can we throw at these batteries to replicate the accidents we were hearing about? No one had anything to add, short of putting these batteries directly in a fire (which we did). We were able to add LiFePO 4 batteries to a local International Association of Arson Investigators (IAAI) boat burn--even there, no one detected any indication that the batteries themselves contributed to the fire. Many of us were fully expecting a report where we were able to replicate an unsafe situation and make some recommendations.

Our full report will be sent to the USCG in due course, and then ABYC will report on our findings. This being a mere President's letter please take it as what it is: My observations while watching our Technical Department do some great work. But, the research and testing may show us that we must take this discussion to the test labs for another round. Our common sense approach to testing has proven again to be the foundation for getting to the bottom of a scenario many of us (including myself) thought would reveal itself in short order. Stand by for formal reporting as we continue our work.

- John

jadey@abycinc.org

[Dignity]

Good to see, a lot of reports on lithium battery fires are based on lithium ion batteries, know of several boats that had them before LiFePo4 came along and they were quick to change over to them.

[NAGG]

Yep use the right terminology - LIFePO4 as opposed to just calling them Lithium ..... no different to a wet lead acid vs AGM , Vs Gel Vs Calcium - all the same but not

Chris

[Lovey80]

I think the Tesla and other EV fires that use different lithium chemistries have given the LifePo4 range an unfairly bad reputation. The Nickel Cobalt chemistries have a much higher energy density with flat charge curves like a lead acid battery. If I remember correctly the three main chemistries: NMC, LCO and LMO all like being between 20-80% SOC. Keeping them fully charged seriously deteriorates the life of the batteries and can cause significant heat spikes in the chemistry that can get easily to the thermal runaway point, which is lower than LifePo4. Not good in a boat that could be running for hours on end.

LifePo4 doesn’t mind being constantly between 10% and 98% and doesn’t generate the same sort of heat when fully charged or discharged. You can even draw them all the way down to 10v as long as they don’t stay there for long before recharging with little degradation. They also have a much longer cycle life if used properly.

LTO (Titanate-Oxide) on the other hand is the complete opposite of the Nickel Cobalt chemistries. The lowest energy density, zero thermal runaway, and incredible charge and discharge rates. A small LTO will have no trouble starting a big mine truck. It will also do 20,000 full cycles before getting to 80% of original capacity.

it’s like each difference in the chemistry is a three way pay off between density/safety/longevity. The denser the energy is the less safe it is and the shorter the life span.

[fishtragic]

Others are obviously all over the chemistry and technology but for real world advice I went through the whole 'we don't recommend using Lithium batteries" chestnut from MK. I have had 3 120 Ah Itechworld LiPo4 batts in series on my MK for 3.5 years. Initially I fried the MK twice in the first 12 months because the Batts were supplying 41V which is catastrophic to the electronics in the MK when it's pulling high amps. To BLA's credit they did all repairs under warranty. Since then I have asked all over the planet for a solution to the high voltage delivery. One electronics co. was willing to make me a voltage reduction device for $4000 and said it' won't be salt resistent and might last a year or two and the size of a shoe box. Chatting to an old mate from the pit one day, he casualy says "oh I can fix that easily". He built me a little VRD with a series of 3 diodes and a little fan cost about $100 and works like a charm 37v from the batts now. I have had zero problems since. MK or BLA now have there own rebadged LiPo4 batts and I'm not sure if they have upgraded the tech. in my earlier repairs but doesn't seem to be a problem now. Just be aware that they still say 'don't go over 7 on the power and it should be fine'.

[tunaticer]

Anyone hear of any prismatic LifePo4 batteries going up in smoke?
Hear of the odd small cell types going up occasionally.

Read just before Xmas that the fire brigade has attended 3 times the previous year's lithium fires mostly in domestic uses. Hundreds of fires in NSW alone attributed to recharging lithium batteries....mobile phones especially.

[Dignity]

Anyone hear of any prismatic LifePo4 batteries going up in smoke?
Hear of the odd small cell types going up occasionally.

Read just before Xmas that the fire brigade has attended 3 times the previous year's lithium fires mostly in domestic uses. Hundreds of fires in NSW alone attributed to recharging lithium batteries....mobile phones especially.

Haven't heard any specifics about which type have caught fire.
Lithium Ion ones are notorious, remember a few years back Samsung had an issue where their phones were catching fire, they had the BMS screwed. My wifes cousins grandson in Latvia had one catch fire only a couple of months back. The firies who attended told them it was more common than people realised and mostly it was the chargers catching fire but in this case it was the phone. A lot of damage was caused by such a small item.

[ranmar850]

Haven't heard any specifics about which type have caught fire.
Lithium Ion ones are notorious, remember a few years back Samsung had an issue where their phones were catching fire, they had the BMS screwed. My wifes cousins grandson in Latvia had one catch fire only a couple of months back. The firies who attended told them it was more common than people realised and mostly it was the chargers catching fire but in this case it was the phone. A lot of damage was caused by such a small item.

Originally Posted by tunaticer

Anyone hear of any prismatic LifePo4 batteries going up in smoke?
Hear of the odd small cell types going up occasionally.

Read just before Xmas that the fire brigade has attended 3 times the previous year's lithium fires mostly in domestic uses. Hundreds of fires in NSW alone attributed to recharging lithium batteries....mobile phones especially

Read an excerpt from the recent NSW Fire Brigade report on fires attributed to lithium batteries. Firstly, the main culprit was Lithium ION , not Lithium Iron phosphate (LiFEPo4). A lot of them where down to the charging of these cheap electric scooters and e-bikes, which are all using Lithium Ion. Power tools were also a culprit, and these are also use Lithium ION. They did note that non-genuine batteries were involved in a disproportionate amount of cases, with the battery tools under charge. So the lesson is, take care with Lithium Ion.
If you can't get someone to get their head around the difference, use this explanation. Explain what energy density is, by holding up your phone, describing how small the battery actually is, then remind them it likely has a rating of about 4.5 ah. Then show them the size of a 100ah LIFePo4. If it comes down to actual mishandling, I'd actually rather be dealing with a LIFEPO4 than lead acid. What happens if you short the terminals on a lead acid? If the shorting object stays intact, you have red heat and the possibility of a fire almost instantaneously. Short the terminals on a LiFePo4, and the BMS will hit peak discharge, then disconnect. One good reason the stick with a good brand of lithium--shortcuts in cost will involve the quality of the BMS fitted, most likely.

[chris69]

Anyone hear of any prismatic LifePo4 batteries going up in smoke?
Hear of the odd small cell types going up occasionally.

Read just before Xmas that the fire brigade has attended 3 times the previous year's lithium fires mostly in domestic uses. Hundreds of fires in NSW alone attributed to recharging lithium batteries....mobile phones especially.

Yer there’s been a few scooters burning down houses ,alls I no is that when the lithiums catch on fire and start burning they make there own oxygen hence fueling the fire even more ,if you see a hybrid car on fire run far away from it.