MacGregorSailors.com

Having recently watched a Tesla in florida on TV catch fire, be put out and recombust to flames again and again I will probable wait for some thing better. The lithium and salt water don't seem to give a safe result . Tesla recomends a safe distance from your residence in case of fire.

This is my thoughts, I'm not sure I could be persuaded to use litium batteries over a lead acid deep cycle battery.

I saw this :

“However, lithium-ion batteries are extremely sensitive to high temperatures and inherently flammable. These battery packs tend to degrade much faster than they normally would, due to heat. If a lithium-ion battery pack fails, it will burst into flames and can cause widespread damage. This calls for immediate measures and guidelines for battery safety.”

https://www.ionenergy.co/resources/blog ... ry-safety/

Good info:

It mostly comes down to chemistry when dealing with lithium batteries. There are many types and a disreputable company will make it difficult to determine the battery chemistry and what type of BMS, if any, it has on board. Of course reputable companies that are forthcoming with all this info are probably going to cost more for better quality and piece of mind. Regarding saltwater, what you are worried about is the salt water acting as a conductor and shorting out the battery. This is of course a potential problem. Some BMS systems have short circuit protection, but this is often for a physical, accidental short like dropping a wrench across the terminals. If the salt water infiltrates the BMS circuitry, all bets are off. There is the potential that the BMS itself is insulated and waterproof, but the manufacturer would have to provide that info.

Anecdotally, this info tracks closely with my experience and research on lithium cells for r/c hobby stuff. I use different chemistry lithium batteries in cars, planes, boats, seaplanes etc. I mostly use lipo because of the higher nominal voltage, but they are potentially more volatile. No BMS whatsoever btw, but this is hobby grade stuff, not critical safety related equipment like a boat battery.

LakeMac26C,

What is your opinion of the videos in Jimmy’s post? How relatable to your post?

I thought both videos were great. I wish they talked more about shorting risks and seawater issues. The information about the regulated alternator is new to me, but something I had heard of being a risk. Please be aware that all of my comments are my thoughts on the issue and am in no way an expert on these systems. Another issue I've considered is the corrosion factor on the wiring itself. Corrosion can create higher resistance in the circuit. With a traditional lead acid, the energy potential in the battery isn't as great and I ASSUME that with the higher output of a lithium that mitigating corrosion would be a greater factor. I'm still very apprehensive about lithium technology especially on a thing like a boat, but I want to adopt lithium as much as possible.

I replaced my motorcycle battery with a cheap lithium "drop in" battery with undisclosed chemistry and BMS. It's a risk I feel I'm willing to take. I suspect my alternator is not setup for this system and need more reliable info, which is a fundamental problem these days

Thanks for a thorough reply.

Another problem not a word of on the MSM is how long will insurance cover a known problem before dropping coverage for all, and is the loss of your insurance worth it , to me not so much. Thanks for the well done video's and comments. Be aware some are on fresh water but not all, salt water seems to make it a real problem to put out. Another is most of the batteries in question are made in China with what ingredients, who knows.

LakeMac as to your motorcycle a fire on a bike is no fun, mine was an open gas cock on a triumph twin outlet tank on a 45 inch Harley using only one gas cock the fire was spectacular to everyone but me, NOT FUN at all.

I hear you about the mcycle fire! I had my "fire crotch" experience years ago on a friend's bike we were troubleshooting. I was trying to diagnose a intake valve or carburetor issue. The more I cranked the bike with the throttle valve partially open, the more it sounded like it would finally start. Until it backfired!!! A loud fireball burst out of the carb right into my crotch!! We took the air filter, fuel tank, and seat off to diagnose it and I had to swat the fire out with an oily rag! Meanwhile, I was holding a funnel full of "tester fuel" going into the carb so I couldn't go more than a couple feet from the bike fire without spilling the fuel. My friend was just paralyzed with shock.

I'm expecting great things from the aliens on planet X, myself

bubby-joe wrote: ↑Wed Oct 12, 2022 9:05 pm Having recently watched a Tesla in florida on TV catch fire, be put out and recombust to flames again and again I will probable wait for some thing better. The lithium and salt water don't seem to give a safe result . Tesla recomends a safe distance from your residence in case of fire.

This is my thoughts, I'm not sure I could be persuaded to use litium batteries over a lead acid deep cycle battery.

Lithium is dangerous and will explode if overcharged or overheated. Even with BMS to sense overages and temperatures there are still problems where the battery gets too hot and can't discharge. That makes the battery swell up and anytime the structure of the battery is deformed it can result in a short. If they short they make flames and fire and stuff.
I would not replace the batteries in 'boat' with lithium.
They all seem to use those little individual 18650 batteries (even some Tesla cars)

The portable solar generators might be a better option to add lithium to your boat because when those catch on fire you can throw them overboard and get the fire off the ship quickly.

When talking about “lithium” it helps to be a little more specific. There are a few chemistries, but lithium iron phosphate seems to be the one that is used for most larger batteries, like car/power sports and solar storage. LFP is significantly more stable (and a little cheaper I think) than the chemistries used in phones or laptops. It’s not as energy dense as other lithiums, which is why it’s not used for smaller devices, but way lighter than lead-acid, so it makes sense as a LA replacement.

I don’t know enough to say if LFP is ‘safe’, but I think it’s a lot safer than powering your boat off a bunch of laptop batteries.

I have always been a big booster for electric cars and stuff but the truth is that a very tiny amount of gasoline will produce enough electricity to replace a hundred batteries. Comparing 13 ounces of gasoline against 217 pounds of lithium sort of negates the environmental benefits. I think it's probably more "green" to just run your outboard for 30 minutes every few days and charge all the batteries on board than to add another 100 pounds of lithium waste products. That's where a solar generator attached to a solar panel may be a good idea. The charge controllers on the panels also give the battery a way to discharge in case of overheating.
I am considering adding a lithium starter pack but the statistics on them are not good - about 1 out of every 10,000 packs catch fire.

As the original poster cited, this subject does deserve some thought.

"I am considering adding a lithium starter pack but the statistics on them are not good - about 1 out of every 10,000 packs catch fire."

"As the original poster cited, this subject does deserve some thought."


For my 2 cents worth any lithium battery source needs about 10 years more work. This to include electric cars,bikes,cell phones computers anywhere a lithium pack is used in my opinion there safety records say it all AVOID AT ALL COST, my life is worth more than taking a chance at this time maybe the future can work around the problems without the problems as they exist being a safety problem.