Review: Cozy Winters heated vest

[Web Monkey]

:11:

Cripes, that would be inconvenient.

Yeah, that could ruin the whole dive.

http://www.elecdesign.com/Articles/Index.cfm?AD=1&ArticleID=13385

I forgot to mention that once it catches fire, it provides it's own O2, so it's pretty much impossible to put out, and sprays out molten lithium to the surrounding areas, which then also catch fire.

This method could provide more warmth than is desired.

Terry

 

[Green_Manelishi]

Yeah, that could ruin the whole dive.

http://www.elecdesign.com/Articles/Index.cfm?AD=1&ArticleID=13385

I forgot to mention that once it catches fire, it provides it's own O2, so it's pretty much impossible to put out, and sprays out molten lithium to the surrounding areas, which then also catch fire.

This method could provide more warmth than is desired.

Terry

Sounds frighteningly like an experience with white phosphorus; it just keeps burning and burning.

 

[cool_hardware52]

LIon batteries have the disturbing habit of catching fire when they short out.

I'm not sure I'd want one zipped up into a drysuit with me.

Terry

I have no specific knowledge of the Li-Ion pack in this application.

Li-ion batteries most commonly "vent with flame" during a recharge that follows an over discharge. The classic failure is a Cellphone on a charging cradle.

A properly designed Li-Ion pack will include over current protection, over charge, and over discharge protection.

Some Li-Ion cells can still be shorted even if the pack includes over current protection if the cells are physically damaged, i.e. crushed.

I would guess that an impact great enough to crush the pack would cause other problems for the diver.

The cells that we use in our scooter batteries have been: flooded at depth (for testing purposes, not in a scooter) hit with a hammer, penetrated wih a nail and cut in half with a band saw. Each destroyed the battery, none resulted in "venting with flame"

When cut or penetrated the cells sparked a bit, and lost some solvent, but did not catchfire.

Not all Li-Ion cells are created equal...

Tobin

 

[TSandM]

Thanks, Tobin. That makes me feel better.

For what it's worth, the battery that comes with this vest is completely sealed in a heavy plastic box, except for the two jacks for plugging into the vest and for charging. It would be quite simple to duct tape or otherwise seal those two points for underwater use, if I were so inclined.

 

[ericfine50]

Do you see any issues with decompression if the batteries die at depth and you get cold as you ascend?

 

[cool_hardware52]

Do you see any issues with decompression if the batteries die at depth and you get cold as you ascend?

Would battery failure be any worse than a major flood?

Tobin

 

[ericfine50]

Very true- I guess I was wondering what would happen when the batteries die and the body cools. Batteries blowing-up would just suck.

 

[Doc Intrepid]

Thanks, Tobin. That makes me feel better.

For what it's worth, the battery that comes with this vest is completely sealed in a heavy plastic box, except for the two jacks for plugging into the vest and for charging. It would be quite simple to duct tape or otherwise seal those two points for underwater use, if I were so inclined.

AquaSeal. The stuff will work fine.

Glad the vest keeps you warm and good luck with your Rec Triox course, and of course we want a detailed trip report!

Break a leg,

Doc

 

[TSandM]

Just for additional information . . . Because I was rushing, trying to get into the water this morning, I forgot to activate the vest. Although I was not as warm as I have been when it's been on, I was certainly as warm as I have been in the Thinsulate vest it replaced.

I was actually talking to rjack and his wife at the dive site today, and I made the point that worrying about what happens if the battery fails on deco is quite akin to thinking about what you do if you get a suit flood on deco. But you don't NOT use a suit, just because it might flood, and I'm not going to NOT use the vest, just because it might fail. And today's dive proves that, even if it does, it has a significant amount of insulating quality in its own right.

PS -- My husband bought one, too, and he loves his . . .

 

[cool_hardware52]

Very true- I guess I was wondering what would happen when the batteries die and the body cools. Batteries blowing-up would just suck.

The idea that a Li-Ion battery suffering a flood in sea water would result in a flood is not proven. In fact the opposite is true, flooding with salt water used to slowly discharge large batteries that are in "running away"

Anytime you have potential energy, high pressure gas, high energy batteries, or even a brick on self over your head, you need to be careful.

With a heated vest I want to make sure there is overcurrent protection (fuse or poly switch) A shorted wire can go incandscent, ouch!

Most known dramatic Li-Ion battery failures occur during recharging that follows an overdischarge. If the pack has overdischarge protection this is much less of a concern, I'd be very surprised if the pack in vest does not have a low voltage cutoff.

Recharging outside your residence is not unreasonable.


Tobin