Tough love for the industry's lithium addiction

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And, You are likely working on IMO SOLAS vessels with ISSS and all of the bells and whistles. These are not SOLAS boats, there is no (or very little) structural fire protection, there is no flame rated walls, the requirement is that they are built of "flame retardant materials" for which a spec doesn't exist. From the pictures, the bunk rails were wood (as were mine). To make regular wood "fire resistant" would be cost prohibitive. Probably didn't happen. There is no UL standard for mattresses. There is no UL standard for fabric to make bunk curtains out of.

Everything in a container ship (I have an unlimited domestic and International Engineer's license, there isn't much I haven't sailed on from VLCC, aircraft carriers, tin cans, drill ships, and having owned a liveaboard or 2 very similar to this one) is designed to not spread fire. Nothing on a dive boat liveaboard is so designed. They are designed for max comfort and max revenue in a minimum space consistent with regulations that are in place for the route and regulations of the boat.

You can find the regulations in 46 CFR subchapter T for the general boat design, and it will send you out to Subchapter S for stability, subchapter I for fire protection, etc.

Read them to your heart's content, then come back and tell me all about small passenger vessel design and how a consumer type LiON battery won't start a fire.
 
Lithium ion batteries are the most dangerous battery chemistry in widespread use. They have resulted in numerous fires, some serious, and have been subject to recalls and to various restrictions on transportation. @Wookie has written in several threads that, while operating m/v Spree, he routinely threw lithium batteries overboard that were overheating, smoking, etc., because of the hazard posed to those aboard.

Many have engaged in informed speculation that the loss of the m/v Conception, with considerable loss of life, could have been caused by a lithium battery fire.

Lithium batteries aren't necessary for diving and could easily be entirely eliminated from the sport.

How we got here

Lithium batteries have the highest specific power capacity of any battery technology, with the common 18650 cells -- that weigh 50 grams -- capable of delivering as much as 80 watts for a few minutes. They also have the highest specific energy capacity, typically delivering around 10 watt-hours over the course of a discharge cycle. Most underwater lights and camera equipment use 18650 cells -- either individually, in removable packs, or as an integral part of the equipment.

Li-ion batteries are used in high-end equipment not because they are necessary but because it is a competitive differentiator to have a device that is smaller and lighter, even when these differences have no effect on the convenience or usability of the device.

Nickel-metal hydride

NIckel-metal hydride (NiMH) batteries are much safer. The AA size is most common, and has almost exactly half the weight and volume of an 18650 cell. The best NiMH cells for photography (and diving), including Eneloop Pro and similar competing cells, deliver a maximum of 4.5 watts per cell, and can deliver 1.6 watt-hours per cell over the course of a fairly rapid 20 minute discharge cycle, and 2.5 watt-hours if discharged over the course of two hours.

If you do a little math, you can see that, for comparable size and weight, lithium batteries deliver 2-3 times the amount of energy and around 10 times the amount of power, compared to NiMH. Before the hazards posed by lithium batteries were well understood, this seemed like an easy tradeoff. The only real drawback was cost, and dive gear is expensive enough that the battery cost isn't much of a factor.

For products that are designed to operate for 30 minutes or more on a charge, the energy limit determines how many batteries are needed to meet the needs of a particular device and application. Nearly all diving gear falls into this category, since equipment is expected to function for the typical 50 minute duration of a dive.

NiMH as a good-enough alternative

For most diving applications, NiMH batteries are good enough.

For this discussion, keep in mind that rechargeable batteries can be combined into packs for ease of handling when more than a few cells are required.

A typical handheld dive light uses one 18650 cell and weighs about 200 grams. A well designed alternative using four AA NiMH cells would have similar performance. The weight of the extra batteries would add 50 grams. The change in bulk would be insignificant.

The largest handheld dive lights (billed as "handheld primary lights") use four 18650 cells. With careful design, NiMH batteries could still be accommodated without having to resort to a canister design.

The only SCUBA product where the energy density requirement is so compelling that lithium-ion batteries are the only practicable solution is scooters.

Other benefits of NiMH

NiMH batteries offer practical benefits insofar as there are no restrictions on transporting them. There are long-life versions available that will last ten years or more even with regular use.

Withering defenses of Li-ion

Many of the problems with lithium batteries can be traced to poor quality control at the time the batteries were manufactured. Some can be traced to poorly designed charging and utilization circuits. Some are caused by impact or other damage to the battery. They are fragile, dropping them on a concrete floor from waist height can cause latent damage.

So there are going to be people who say that if you use high quality batteries and are nice to them, everything will be OK.

And for people who believe that, I'm going to say that there are some really smart people at Samsung and Apple and other high-end electronics manufacturers that work in huge volumes, and they couldn't figure it out. Are you smarter than they are? Do you know your supply chain better than they do?

Tough love

Got lithium? Get rid of it. Don't buy any more.

Use lights that operate on AA cells and use NiMH cells in them. When shopping, reviewing, etc., insist that vendors use the safest technology. You wouldn't buy a regulator that weighs less if it were less safe, so why would you buy a dive light that weighs less but is less safe?

Got a dive boat? Don't allow lithium batteries on it. Period. There are alternatives.

Got a dive shop? You get the picture....
To me, this is an unnecessary overreaction - "throwing out the baby with the bathwater" as they say. Lithium-ion batteries certainly can be dangeous if proper controls in manufacturing, storage and use are not followed - but many things we use daily fall into that same bucket!

For example, should I propose to ban dogs in people's houses just because I discovered tht my dog had chewed the power cable to my printer the other day when I moved the computer and heard /saw a the "pop/spark" as the wire shorted!? Of course not!

There are significant benefits (as you captured) to Li-ion batteries properties of compact, long-life and high output power that don't need to be dumped based on this current, tragic accident (if it was even related to Li-ion batteries as there is ZERO proof of that as the root cause at this point - just internet "experts" speculating)!

I think a better solution is to modify how we handle/use these types of batteries. In the case of live-aboard dive boats, maybe they should not allow chariging in non-dedicated and isolated charging stations in locations that could pose a risk of igniting the vessel in a failure. Perhaps a location on deck that could even be jettisoned overboard in the event of a catostrophic failure of some type? Perhaps not allow unattended/monitored/overnight charging.

Ther are lots of corrective and preventive measures that can be implemented before we just jump to ditching this technology.
 
My recollection of my most recent liveaboard was that they allowed charging in the cabins ONLY while occupied. If you left your cabin, you were supposed to suspend your charging. Charging using any of the many outlets in the salon was permitted, at least during the day; I do not recall whether overnight charging in the salon was permitted.
without any blame to assumptions regarding the recent incident.. and in general...

Asking your customers not to leave charging device in their berths without a SOP in place where a crew member verifies they are following the rules would not work.

I would not permit charging of devices in a berth if I were master of a vessel, it's an environment that is likely to promote thermal issues with charging (bedding blocks ventilation and also insulates) and is the perfect conditions to rapidly spread any combustion. I don't even allow it in my home, to the ongoing chagrin of my 12 year old and wife.
 
Show me a USCG inspected vessel that has any of these things in any passenger compartment and we'll continue the conversation.

Sorry, it sounded like your original post was calling for divers to stop using lithium-ion batteries because they are too dangerous and nimh is a close enough option. "Managing" the risk of lithium-ion battery charging could certainly mean no charging allowed in a passenger compartment, or charging in a specific area that has suppression equipment.
 
Thanks, CFR 46/T is an interesting reading, section 180 especially. I could not find the answer to your question, though, " how a consumer type LiON battery won't start a fire". Maybe it will, maybe not.
 
Can we at least agree on whether we're discussing lithium batteries or lithium-ion batteries before we continue with the bickering and ad hominems? Li and Li-ion are two quite different beasts.
 
Can we at least agree on whether we're discussing lithium batteries or lithium-ion batteries before we continue with the bickering and ad hominems? Li and Li-ion are two quite different beasts.
indeed, and even in Lithium Ion batteries that are the same size (say an 18650) but have different amp hour ratings can vary greatly in risk. The higher the less margin for error and stored energy. Add in multi cell packs and more comes into play, along with type and quality of charger.

Lithium non rechargeable batteries have a thin wrap of pure lithium, that if dropped in water will catch on fire.

here is a good discussion of Li Ion

Safety Concerns with Li-ion Batteries – Battery University
 
"flame retardant materials" for which a spec doesn't exist

Maybe you are referring to something else, but the regulations you referenced, in section 177.410, say:
"When the hull, bulkheads, decks, deckhouse, or superstructure of a vessel is partially or completely constructed of a composite material, including fiber reinforced plastic, the resin used must be fire retardant and meet as accepted by the Commandant as meeting NPFC MIL-R-21607E(SH) (incorporated by reference, see 46 CFR 175.600). Resin systems that have not been accepted as meeting NPFC MIL-R-21607E(SH) may be accepted as fire retardant if they have an ASTM E-84 flame spread rating of not more than 100 when tested in laminate form."

It's a bit out of my area of expertise, but is this not a specification? Maybe it's not a useful one? I'm not sure if you were actually commenting on all the flammable materials in the boat vs. the wall material itself. I'm guessing that if all the stuff inside the compartment caught fire, that the flammability rating of the frp would be easily overcome.
 
Maybe you are referring to something else, but the regulations you referenced, in section 177.410, say:
"When the hull, bulkheads, decks, deckhouse, or superstructure of a vessel is partially or completely constructed of a composite material, including fiber reinforced plastic, the resin used must be fire retardant and meet as accepted by the Commandant as meeting NPFC MIL-R-21607E(SH) (incorporated by reference, see 46 CFR 175.600). Resin systems that have not been accepted as meeting NPFC MIL-R-21607E(SH) may be accepted as fire retardant if they have an ASTM E-84 flame spread rating of not more than 100 when tested in laminate form."

It's a bit out of my area of expertise, but is this not a specification? Maybe it's not a useful one? I'm not sure if you were actually commenting on all the flammable materials in the boat vs. the wall material itself. I'm guessing that if all the stuff inside the compartment caught fire, that the flammability rating of the frp would be easily overcome.
This applies to the vessel structure. I'm referring to all of the junk inside, including mattresses, curtains, pillows, blankets, wood bunk rails, and all of the stuff that burned when my boat burned. My hull was aluminum and not affected at all. Well, except the Coast Guard did make me do a metallurgical survey.
 
Can we at least agree on whether we're discussing lithium batteries or lithium-ion batteries before we continue with the bickering and ad hominems? Li and Li-ion are two quite different beasts.

We are talking about Li-ion batteries, because nobody uses the old non-rechargeable "lithium" cells for diving.

The 18650 lithium-ion cells, which are the most widely used in dive equipment (and elsewhere), have resulted in plenty of fires:

When Your Amazon Purchase Explodes
Don't Blame the Batteries For Every Lithium-Ion Explosion
https://www.researchgate.net/public...650_lithium_ion_batteries_by_fire_calorimeter
 
https://www.shearwater.com/products/teric/

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